0471f88004836df15f2da6b3bba4ead0489e4439
[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(sg_virt(&cmd->SCp.buffer[1])) == endaddr;) {
481                 MER_PRINTK("VTOP(%p) == %08lx -> merging\n",
482                            page_address(sg_page(&cmd->SCp.buffer[1])), endaddr);
483 #if (NDEBUG & NDEBUG_MERGING)
484                 ++cnt;
485 #endif
486                 ++cmd->SCp.buffer;
487                 --cmd->SCp.buffers_residual;
488                 cmd->SCp.this_residual += cmd->SCp.buffer->length;
489                 endaddr += cmd->SCp.buffer->length;
490         }
491 #if (NDEBUG & NDEBUG_MERGING)
492         if (oldlen != cmd->SCp.this_residual)
493                 MER_PRINTK("merged %d buffers from %p, new length %08x\n",
494                            cnt, cmd->SCp.ptr, cmd->SCp.this_residual);
495 #endif
496 }
497
498 /*
499  * Function : void initialize_SCp(Scsi_Cmnd *cmd)
500  *
501  * Purpose : initialize the saved data pointers for cmd to point to the
502  *      start of the buffer.
503  *
504  * Inputs : cmd - Scsi_Cmnd structure to have pointers reset.
505  */
506
507 static inline void initialize_SCp(Scsi_Cmnd *cmd)
508 {
509         /*
510          * Initialize the Scsi Pointer field so that all of the commands in the
511          * various queues are valid.
512          */
513
514         if (scsi_bufflen(cmd)) {
515                 cmd->SCp.buffer = scsi_sglist(cmd);
516                 cmd->SCp.buffers_residual = scsi_sg_count(cmd) - 1;
517                 cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
518                 cmd->SCp.this_residual = cmd->SCp.buffer->length;
519                 /* ++roman: Try to merge some scatter-buffers if they are at
520                  * contiguous physical addresses.
521                  */
522                 merge_contiguous_buffers(cmd);
523         } else {
524                 cmd->SCp.buffer = NULL;
525                 cmd->SCp.buffers_residual = 0;
526                 cmd->SCp.ptr = NULL;
527                 cmd->SCp.this_residual = 0;
528         }
529 }
530
531 #include <linux/delay.h>
532
533 #if NDEBUG
534 static struct {
535         unsigned char mask;
536         const char *name;
537 } signals[] = {
538         { SR_DBP, "PARITY"}, { SR_RST, "RST" }, { SR_BSY, "BSY" },
539         { SR_REQ, "REQ" }, { SR_MSG, "MSG" }, { SR_CD,  "CD" }, { SR_IO, "IO" },
540         { SR_SEL, "SEL" }, {0, NULL}
541 }, basrs[] = {
542         {BASR_ATN, "ATN"}, {BASR_ACK, "ACK"}, {0, NULL}
543 }, icrs[] = {
544         {ICR_ASSERT_RST, "ASSERT RST"},{ICR_ASSERT_ACK, "ASSERT ACK"},
545         {ICR_ASSERT_BSY, "ASSERT BSY"}, {ICR_ASSERT_SEL, "ASSERT SEL"},
546         {ICR_ASSERT_ATN, "ASSERT ATN"}, {ICR_ASSERT_DATA, "ASSERT DATA"},
547         {0, NULL}
548 }, mrs[] = {
549         {MR_BLOCK_DMA_MODE, "MODE BLOCK DMA"}, {MR_TARGET, "MODE TARGET"},
550         {MR_ENABLE_PAR_CHECK, "MODE PARITY CHECK"}, {MR_ENABLE_PAR_INTR,
551         "MODE PARITY INTR"}, {MR_ENABLE_EOP_INTR,"MODE EOP INTR"},
552         {MR_MONITOR_BSY, "MODE MONITOR BSY"},
553         {MR_DMA_MODE, "MODE DMA"}, {MR_ARBITRATE, "MODE ARBITRATION"},
554         {0, NULL}
555 };
556
557 /*
558  * Function : void NCR5380_print(struct Scsi_Host *instance)
559  *
560  * Purpose : print the SCSI bus signals for debugging purposes
561  *
562  * Input : instance - which NCR5380
563  */
564
565 static void NCR5380_print(struct Scsi_Host *instance)
566 {
567         unsigned char status, data, basr, mr, icr, i;
568         unsigned long flags;
569
570         local_irq_save(flags);
571         data = NCR5380_read(CURRENT_SCSI_DATA_REG);
572         status = NCR5380_read(STATUS_REG);
573         mr = NCR5380_read(MODE_REG);
574         icr = NCR5380_read(INITIATOR_COMMAND_REG);
575         basr = NCR5380_read(BUS_AND_STATUS_REG);
576         local_irq_restore(flags);
577         printk("STATUS_REG: %02x ", status);
578         for (i = 0; signals[i].mask; ++i)
579                 if (status & signals[i].mask)
580                         printk(",%s", signals[i].name);
581         printk("\nBASR: %02x ", basr);
582         for (i = 0; basrs[i].mask; ++i)
583                 if (basr & basrs[i].mask)
584                         printk(",%s", basrs[i].name);
585         printk("\nICR: %02x ", icr);
586         for (i = 0; icrs[i].mask; ++i)
587                 if (icr & icrs[i].mask)
588                         printk(",%s", icrs[i].name);
589         printk("\nMODE: %02x ", mr);
590         for (i = 0; mrs[i].mask; ++i)
591                 if (mr & mrs[i].mask)
592                         printk(",%s", mrs[i].name);
593         printk("\n");
594 }
595
596 static struct {
597         unsigned char value;
598         const char *name;
599 } phases[] = {
600         {PHASE_DATAOUT, "DATAOUT"}, {PHASE_DATAIN, "DATAIN"}, {PHASE_CMDOUT, "CMDOUT"},
601         {PHASE_STATIN, "STATIN"}, {PHASE_MSGOUT, "MSGOUT"}, {PHASE_MSGIN, "MSGIN"},
602         {PHASE_UNKNOWN, "UNKNOWN"}
603 };
604
605 /*
606  * Function : void NCR5380_print_phase(struct Scsi_Host *instance)
607  *
608  * Purpose : print the current SCSI phase for debugging purposes
609  *
610  * Input : instance - which NCR5380
611  */
612
613 static void NCR5380_print_phase(struct Scsi_Host *instance)
614 {
615         unsigned char status;
616         int i;
617
618         status = NCR5380_read(STATUS_REG);
619         if (!(status & SR_REQ))
620                 printk(KERN_DEBUG "scsi%d: REQ not asserted, phase unknown.\n", HOSTNO);
621         else {
622                 for (i = 0; (phases[i].value != PHASE_UNKNOWN) &&
623                      (phases[i].value != (status & PHASE_MASK)); ++i)
624                         ;
625                 printk(KERN_DEBUG "scsi%d: phase %s\n", HOSTNO, phases[i].name);
626         }
627 }
628
629 #else /* !NDEBUG */
630
631 /* dummies... */
632 static inline void NCR5380_print(struct Scsi_Host *instance)
633 {
634 };
635 static inline void NCR5380_print_phase(struct Scsi_Host *instance)
636 {
637 };
638
639 #endif
640
641 /*
642  * ++roman: New scheme of calling NCR5380_main()
643  *
644  * If we're not in an interrupt, we can call our main directly, it cannot be
645  * already running. Else, we queue it on a task queue, if not 'main_running'
646  * tells us that a lower level is already executing it. This way,
647  * 'main_running' needs not be protected in a special way.
648  *
649  * queue_main() is a utility function for putting our main onto the task
650  * queue, if main_running is false. It should be called only from a
651  * interrupt or bottom half.
652  */
653
654 #include <linux/workqueue.h>
655 #include <linux/interrupt.h>
656
657 static volatile int main_running;
658 static DECLARE_WORK(NCR5380_tqueue, NCR5380_main);
659
660 static inline void queue_main(void)
661 {
662         if (!main_running) {
663                 /* If in interrupt and NCR5380_main() not already running,
664                    queue it on the 'immediate' task queue, to be processed
665                    immediately after the current interrupt processing has
666                    finished. */
667                 schedule_work(&NCR5380_tqueue);
668         }
669         /* else: nothing to do: the running NCR5380_main() will pick up
670            any newly queued command. */
671 }
672
673
674 static inline void NCR5380_all_init(void)
675 {
676         static int done = 0;
677         if (!done) {
678                 INI_PRINTK("scsi : NCR5380_all_init()\n");
679                 done = 1;
680         }
681 }
682
683
684 /*
685  * Function : void NCR58380_print_options (struct Scsi_Host *instance)
686  *
687  * Purpose : called by probe code indicating the NCR5380 driver
688  *           options that were selected.
689  *
690  * Inputs : instance, pointer to this instance.  Unused.
691  */
692
693 static void __init NCR5380_print_options(struct Scsi_Host *instance)
694 {
695         printk(" generic options"
696 #ifdef AUTOSENSE
697                " AUTOSENSE"
698 #endif
699 #ifdef REAL_DMA
700                " REAL DMA"
701 #endif
702 #ifdef PARITY
703                " PARITY"
704 #endif
705 #ifdef SUPPORT_TAGS
706                " SCSI-2 TAGGED QUEUING"
707 #endif
708                );
709         printk(" generic release=%d", NCR5380_PUBLIC_RELEASE);
710 }
711
712 /*
713  * Function : void NCR5380_print_status (struct Scsi_Host *instance)
714  *
715  * Purpose : print commands in the various queues, called from
716  *      NCR5380_abort and NCR5380_debug to aid debugging.
717  *
718  * Inputs : instance, pointer to this instance.
719  */
720
721 static void NCR5380_print_status(struct Scsi_Host *instance)
722 {
723         char *pr_bfr;
724         char *start;
725         int len;
726
727         NCR_PRINT(NDEBUG_ANY);
728         NCR_PRINT_PHASE(NDEBUG_ANY);
729
730         pr_bfr = (char *)__get_free_page(GFP_ATOMIC);
731         if (!pr_bfr) {
732                 printk("NCR5380_print_status: no memory for print buffer\n");
733                 return;
734         }
735         len = NCR5380_proc_info(instance, pr_bfr, &start, 0, PAGE_SIZE, 0);
736         pr_bfr[len] = 0;
737         printk("\n%s\n", pr_bfr);
738         free_page((unsigned long)pr_bfr);
739 }
740
741
742 /******************************************/
743 /*
744  * /proc/scsi/[dtc pas16 t128 generic]/[0-ASC_NUM_BOARD_SUPPORTED]
745  *
746  * *buffer: I/O buffer
747  * **start: if inout == FALSE pointer into buffer where user read should start
748  * offset: current offset
749  * length: length of buffer
750  * hostno: Scsi_Host host_no
751  * inout: TRUE - user is writing; FALSE - user is reading
752  *
753  * Return the number of bytes read from or written
754 */
755
756 #undef SPRINTF
757 #define SPRINTF(fmt,args...)                                                    \
758         do {                                                                    \
759                 if (pos + strlen(fmt) + 20 /* slop */ < buffer + length)        \
760                         pos += sprintf(pos, fmt , ## args);                     \
761         } while(0)
762 static char *lprint_Scsi_Cmnd(Scsi_Cmnd *cmd, char *pos, char *buffer, int length);
763
764 static int NCR5380_proc_info(struct Scsi_Host *instance, char *buffer,
765                              char **start, off_t offset, int length, int inout)
766 {
767         char *pos = buffer;
768         struct NCR5380_hostdata *hostdata;
769         Scsi_Cmnd *ptr;
770         unsigned long flags;
771         off_t begin = 0;
772 #define check_offset()                                  \
773         do {                                            \
774                 if (pos - buffer < offset - begin) {    \
775                         begin += pos - buffer;          \
776                         pos = buffer;                   \
777                 }                                       \
778         } while (0)
779
780         hostdata = (struct NCR5380_hostdata *)instance->hostdata;
781
782         if (inout)                      /* Has data been written to the file ? */
783                 return -ENOSYS;         /* Currently this is a no-op */
784         SPRINTF("NCR5380 core release=%d.\n", NCR5380_PUBLIC_RELEASE);
785         check_offset();
786         local_irq_save(flags);
787         SPRINTF("NCR5380: coroutine is%s running.\n",
788                 main_running ? "" : "n't");
789         check_offset();
790         if (!hostdata->connected)
791                 SPRINTF("scsi%d: no currently connected command\n", HOSTNO);
792         else
793                 pos = lprint_Scsi_Cmnd((Scsi_Cmnd *) hostdata->connected,
794                                        pos, buffer, length);
795         SPRINTF("scsi%d: issue_queue\n", HOSTNO);
796         check_offset();
797         for (ptr = (Scsi_Cmnd *)hostdata->issue_queue; ptr; ptr = NEXT(ptr)) {
798                 pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length);
799                 check_offset();
800         }
801
802         SPRINTF("scsi%d: disconnected_queue\n", HOSTNO);
803         check_offset();
804         for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr;
805              ptr = NEXT(ptr)) {
806                 pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length);
807                 check_offset();
808         }
809
810         local_irq_restore(flags);
811         *start = buffer + (offset - begin);
812         if (pos - buffer < offset - begin)
813                 return 0;
814         else if (pos - buffer - (offset - begin) < length)
815                 return pos - buffer - (offset - begin);
816         return length;
817 }
818
819 static char *lprint_Scsi_Cmnd(Scsi_Cmnd *cmd, char *pos, char *buffer, int length)
820 {
821         int i, s;
822         unsigned char *command;
823         SPRINTF("scsi%d: destination target %d, lun %d\n",
824                 H_NO(cmd), cmd->device->id, cmd->device->lun);
825         SPRINTF("        command = ");
826         command = cmd->cmnd;
827         SPRINTF("%2d (0x%02x)", command[0], command[0]);
828         for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
829                 SPRINTF(" %02x", command[i]);
830         SPRINTF("\n");
831         return pos;
832 }
833
834
835 /*
836  * Function : void NCR5380_init (struct Scsi_Host *instance)
837  *
838  * Purpose : initializes *instance and corresponding 5380 chip.
839  *
840  * Inputs : instance - instantiation of the 5380 driver.
841  *
842  * Notes : I assume that the host, hostno, and id bits have been
843  *      set correctly.  I don't care about the irq and other fields.
844  *
845  */
846
847 static int __init NCR5380_init(struct Scsi_Host *instance, int flags)
848 {
849         int i;
850         SETUP_HOSTDATA(instance);
851
852         NCR5380_all_init();
853
854         hostdata->aborted = 0;
855         hostdata->id_mask = 1 << instance->this_id;
856         hostdata->id_higher_mask = 0;
857         for (i = hostdata->id_mask; i <= 0x80; i <<= 1)
858                 if (i > hostdata->id_mask)
859                         hostdata->id_higher_mask |= i;
860         for (i = 0; i < 8; ++i)
861                 hostdata->busy[i] = 0;
862 #ifdef SUPPORT_TAGS
863         init_tags();
864 #endif
865 #if defined (REAL_DMA)
866         hostdata->dma_len = 0;
867 #endif
868         hostdata->targets_present = 0;
869         hostdata->connected = NULL;
870         hostdata->issue_queue = NULL;
871         hostdata->disconnected_queue = NULL;
872         hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT;
873
874         if (!the_template) {
875                 the_template = instance->hostt;
876                 first_instance = instance;
877         }
878
879 #ifndef AUTOSENSE
880         if ((instance->cmd_per_lun > 1) || (instance->can_queue > 1))
881                 printk("scsi%d: WARNING : support for multiple outstanding commands enabled\n"
882                        "        without AUTOSENSE option, contingent allegiance conditions may\n"
883                        "        be incorrectly cleared.\n", HOSTNO);
884 #endif /* def AUTOSENSE */
885
886         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
887         NCR5380_write(MODE_REG, MR_BASE);
888         NCR5380_write(TARGET_COMMAND_REG, 0);
889         NCR5380_write(SELECT_ENABLE_REG, 0);
890
891         return 0;
892 }
893
894 /*
895  * Function : int NCR5380_queue_command (Scsi_Cmnd *cmd,
896  *      void (*done)(Scsi_Cmnd *))
897  *
898  * Purpose :  enqueues a SCSI command
899  *
900  * Inputs : cmd - SCSI command, done - function called on completion, with
901  *      a pointer to the command descriptor.
902  *
903  * Returns : 0
904  *
905  * Side effects :
906  *      cmd is added to the per instance issue_queue, with minor
907  *      twiddling done to the host specific fields of cmd.  If the
908  *      main coroutine is not running, it is restarted.
909  *
910  */
911
912 static int NCR5380_queue_command(Scsi_Cmnd *cmd, void (*done)(Scsi_Cmnd *))
913 {
914         SETUP_HOSTDATA(cmd->device->host);
915         Scsi_Cmnd *tmp;
916         int oldto;
917         unsigned long flags;
918
919 #if (NDEBUG & NDEBUG_NO_WRITE)
920         switch (cmd->cmnd[0]) {
921         case WRITE_6:
922         case WRITE_10:
923                 printk(KERN_NOTICE "scsi%d: WRITE attempted with NO_WRITE debugging flag set\n",
924                        H_NO(cmd));
925                 cmd->result = (DID_ERROR << 16);
926                 done(cmd);
927                 return 0;
928         }
929 #endif /* (NDEBUG & NDEBUG_NO_WRITE) */
930
931 #ifdef NCR5380_STATS
932 # if 0
933         if (!hostdata->connected && !hostdata->issue_queue &&
934             !hostdata->disconnected_queue) {
935                 hostdata->timebase = jiffies;
936         }
937 # endif
938 # ifdef NCR5380_STAT_LIMIT
939         if (scsi_bufflen(cmd) > NCR5380_STAT_LIMIT)
940 # endif
941                 switch (cmd->cmnd[0]) {
942                 case WRITE:
943                 case WRITE_6:
944                 case WRITE_10:
945                         hostdata->time_write[cmd->device->id] -= (jiffies - hostdata->timebase);
946                         hostdata->bytes_write[cmd->device->id] += scsi_bufflen(cmd);
947                         hostdata->pendingw++;
948                         break;
949                 case READ:
950                 case READ_6:
951                 case READ_10:
952                         hostdata->time_read[cmd->device->id] -= (jiffies - hostdata->timebase);
953                         hostdata->bytes_read[cmd->device->id] += scsi_bufflen(cmd);
954                         hostdata->pendingr++;
955                         break;
956                 }
957 #endif
958
959         /*
960          * We use the host_scribble field as a pointer to the next command
961          * in a queue
962          */
963
964         SET_NEXT(cmd, NULL);
965         cmd->scsi_done = done;
966
967         cmd->result = 0;
968
969         /*
970          * Insert the cmd into the issue queue. Note that REQUEST SENSE
971          * commands are added to the head of the queue since any command will
972          * clear the contingent allegiance condition that exists and the
973          * sense data is only guaranteed to be valid while the condition exists.
974          */
975
976         local_irq_save(flags);
977         /* ++guenther: now that the issue queue is being set up, we can lock ST-DMA.
978          * Otherwise a running NCR5380_main may steal the lock.
979          * Lock before actually inserting due to fairness reasons explained in
980          * atari_scsi.c. If we insert first, then it's impossible for this driver
981          * to release the lock.
982          * Stop timer for this command while waiting for the lock, or timeouts
983          * may happen (and they really do), and it's no good if the command doesn't
984          * appear in any of the queues.
985          * ++roman: Just disabling the NCR interrupt isn't sufficient here,
986          * because also a timer int can trigger an abort or reset, which would
987          * alter queues and touch the lock.
988          */
989         if (!IS_A_TT()) {
990                 /* perhaps stop command timer here */
991                 falcon_get_lock();
992                 /* perhaps restart command timer here */
993         }
994         if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
995                 LIST(cmd, hostdata->issue_queue);
996                 SET_NEXT(cmd, hostdata->issue_queue);
997                 hostdata->issue_queue = cmd;
998         } else {
999                 for (tmp = (Scsi_Cmnd *)hostdata->issue_queue;
1000                      NEXT(tmp); tmp = NEXT(tmp))
1001                         ;
1002                 LIST(cmd, tmp);
1003                 SET_NEXT(tmp, cmd);
1004         }
1005         local_irq_restore(flags);
1006
1007         QU_PRINTK("scsi%d: command added to %s of queue\n", H_NO(cmd),
1008                   (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail");
1009
1010         /* If queue_command() is called from an interrupt (real one or bottom
1011          * half), we let queue_main() do the job of taking care about main. If it
1012          * is already running, this is a no-op, else main will be queued.
1013          *
1014          * If we're not in an interrupt, we can call NCR5380_main()
1015          * unconditionally, because it cannot be already running.
1016          */
1017         if (in_interrupt() || ((flags >> 8) & 7) >= 6)
1018                 queue_main();
1019         else
1020                 NCR5380_main(NULL);
1021         return 0;
1022 }
1023
1024 /*
1025  * Function : NCR5380_main (void)
1026  *
1027  * Purpose : NCR5380_main is a coroutine that runs as long as more work can
1028  *      be done on the NCR5380 host adapters in a system.  Both
1029  *      NCR5380_queue_command() and NCR5380_intr() will try to start it
1030  *      in case it is not running.
1031  *
1032  * NOTE : NCR5380_main exits with interrupts *disabled*, the caller should
1033  *  reenable them.  This prevents reentrancy and kernel stack overflow.
1034  */
1035
1036 static void NCR5380_main(struct work_struct *work)
1037 {
1038         Scsi_Cmnd *tmp, *prev;
1039         struct Scsi_Host *instance = first_instance;
1040         struct NCR5380_hostdata *hostdata = HOSTDATA(instance);
1041         int done;
1042         unsigned long flags;
1043
1044         /*
1045          * We run (with interrupts disabled) until we're sure that none of
1046          * the host adapters have anything that can be done, at which point
1047          * we set main_running to 0 and exit.
1048          *
1049          * Interrupts are enabled before doing various other internal
1050          * instructions, after we've decided that we need to run through
1051          * the loop again.
1052          *
1053          * this should prevent any race conditions.
1054          *
1055          * ++roman: Just disabling the NCR interrupt isn't sufficient here,
1056          * because also a timer int can trigger an abort or reset, which can
1057          * alter queues and touch the Falcon lock.
1058          */
1059
1060         /* Tell int handlers main() is now already executing.  Note that
1061            no races are possible here. If an int comes in before
1062            'main_running' is set here, and queues/executes main via the
1063            task queue, it doesn't do any harm, just this instance of main
1064            won't find any work left to do. */
1065         if (main_running)
1066                 return;
1067         main_running = 1;
1068
1069         local_save_flags(flags);
1070         do {
1071                 local_irq_disable();    /* Freeze request queues */
1072                 done = 1;
1073
1074                 if (!hostdata->connected) {
1075                         MAIN_PRINTK("scsi%d: not connected\n", HOSTNO);
1076                         /*
1077                          * Search through the issue_queue for a command destined
1078                          * for a target that's not busy.
1079                          */
1080 #if (NDEBUG & NDEBUG_LISTS)
1081                         for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL;
1082                              tmp && (tmp != prev); prev = tmp, tmp = NEXT(tmp))
1083                                 ;
1084                         /*printk("%p  ", tmp);*/
1085                         if ((tmp == prev) && tmp)
1086                                 printk(" LOOP\n");
1087                         /* else printk("\n"); */
1088 #endif
1089                         for (tmp = (Scsi_Cmnd *) hostdata->issue_queue,
1090                              prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp)) {
1091
1092 #if (NDEBUG & NDEBUG_LISTS)
1093                                 if (prev != tmp)
1094                                         printk("MAIN tmp=%p   target=%d   busy=%d lun=%d\n",
1095                                                tmp, tmp->device->id, hostdata->busy[tmp->device->id],
1096                                                tmp->device->lun);
1097 #endif
1098                                 /*  When we find one, remove it from the issue queue. */
1099                                 /* ++guenther: possible race with Falcon locking */
1100                                 if (
1101 #ifdef SUPPORT_TAGS
1102                                     !is_lun_busy( tmp, tmp->cmnd[0] != REQUEST_SENSE)
1103 #else
1104                                     !(hostdata->busy[tmp->device->id] & (1 << tmp->device->lun))
1105 #endif
1106                                     ) {
1107                                         /* ++guenther: just to be sure, this must be atomic */
1108                                         local_irq_disable();
1109                                         if (prev) {
1110                                                 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
1111                                                 SET_NEXT(prev, NEXT(tmp));
1112                                         } else {
1113                                                 REMOVE(-1, hostdata->issue_queue, tmp, NEXT(tmp));
1114                                                 hostdata->issue_queue = NEXT(tmp);
1115                                         }
1116                                         SET_NEXT(tmp, NULL);
1117                                         falcon_dont_release++;
1118
1119                                         /* reenable interrupts after finding one */
1120                                         local_irq_restore(flags);
1121
1122                                         /*
1123                                          * Attempt to establish an I_T_L nexus here.
1124                                          * On success, instance->hostdata->connected is set.
1125                                          * On failure, we must add the command back to the
1126                                          *   issue queue so we can keep trying.
1127                                          */
1128                                         MAIN_PRINTK("scsi%d: main(): command for target %d "
1129                                                     "lun %d removed from issue_queue\n",
1130                                                     HOSTNO, tmp->device->id, tmp->device->lun);
1131                                         /*
1132                                          * REQUEST SENSE commands are issued without tagged
1133                                          * queueing, even on SCSI-II devices because the
1134                                          * contingent allegiance condition exists for the
1135                                          * entire unit.
1136                                          */
1137                                         /* ++roman: ...and the standard also requires that
1138                                          * REQUEST SENSE command are untagged.
1139                                          */
1140
1141 #ifdef SUPPORT_TAGS
1142                                         cmd_get_tag(tmp, tmp->cmnd[0] != REQUEST_SENSE);
1143 #endif
1144                                         if (!NCR5380_select(instance, tmp,
1145                                             (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE :
1146                                             TAG_NEXT)) {
1147                                                 falcon_dont_release--;
1148                                                 /* release if target did not response! */
1149                                                 falcon_release_lock_if_possible(hostdata);
1150                                                 break;
1151                                         } else {
1152                                                 local_irq_disable();
1153                                                 LIST(tmp, hostdata->issue_queue);
1154                                                 SET_NEXT(tmp, hostdata->issue_queue);
1155                                                 hostdata->issue_queue = tmp;
1156 #ifdef SUPPORT_TAGS
1157                                                 cmd_free_tag(tmp);
1158 #endif
1159                                                 falcon_dont_release--;
1160                                                 local_irq_restore(flags);
1161                                                 MAIN_PRINTK("scsi%d: main(): select() failed, "
1162                                                             "returned to issue_queue\n", HOSTNO);
1163                                                 if (hostdata->connected)
1164                                                         break;
1165                                         }
1166                                 } /* if target/lun/target queue is not busy */
1167                         } /* for issue_queue */
1168                 } /* if (!hostdata->connected) */
1169
1170                 if (hostdata->connected
1171 #ifdef REAL_DMA
1172                     && !hostdata->dma_len
1173 #endif
1174                     ) {
1175                         local_irq_restore(flags);
1176                         MAIN_PRINTK("scsi%d: main: performing information transfer\n",
1177                                     HOSTNO);
1178                         NCR5380_information_transfer(instance);
1179                         MAIN_PRINTK("scsi%d: main: done set false\n", HOSTNO);
1180                         done = 0;
1181                 }
1182         } while (!done);
1183
1184         /* Better allow ints _after_ 'main_running' has been cleared, else
1185            an interrupt could believe we'll pick up the work it left for
1186            us, but we won't see it anymore here... */
1187         main_running = 0;
1188         local_irq_restore(flags);
1189 }
1190
1191
1192 #ifdef REAL_DMA
1193 /*
1194  * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
1195  *
1196  * Purpose : Called by interrupt handler when DMA finishes or a phase
1197  *      mismatch occurs (which would finish the DMA transfer).
1198  *
1199  * Inputs : instance - this instance of the NCR5380.
1200  *
1201  */
1202
1203 static void NCR5380_dma_complete(struct Scsi_Host *instance)
1204 {
1205         SETUP_HOSTDATA(instance);
1206         int transfered, saved_data = 0, overrun = 0, cnt, toPIO;
1207         unsigned char **data, p;
1208         volatile int *count;
1209
1210         if (!hostdata->connected) {
1211                 printk(KERN_WARNING "scsi%d: received end of DMA interrupt with "
1212                        "no connected cmd\n", HOSTNO);
1213                 return;
1214         }
1215
1216         if (atari_read_overruns) {
1217                 p = hostdata->connected->SCp.phase;
1218                 if (p & SR_IO) {
1219                         udelay(10);
1220                         if ((NCR5380_read(BUS_AND_STATUS_REG) &
1221                              (BASR_PHASE_MATCH|BASR_ACK)) ==
1222                             (BASR_PHASE_MATCH|BASR_ACK)) {
1223                                 saved_data = NCR5380_read(INPUT_DATA_REG);
1224                                 overrun = 1;
1225                                 DMA_PRINTK("scsi%d: read overrun handled\n", HOSTNO);
1226                         }
1227                 }
1228         }
1229
1230         DMA_PRINTK("scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n",
1231                    HOSTNO, NCR5380_read(BUS_AND_STATUS_REG),
1232                    NCR5380_read(STATUS_REG));
1233
1234         (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1235         NCR5380_write(MODE_REG, MR_BASE);
1236         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1237
1238         transfered = hostdata->dma_len - NCR5380_dma_residual(instance);
1239         hostdata->dma_len = 0;
1240
1241         data = (unsigned char **)&hostdata->connected->SCp.ptr;
1242         count = &hostdata->connected->SCp.this_residual;
1243         *data += transfered;
1244         *count -= transfered;
1245
1246         if (atari_read_overruns) {
1247                 if ((NCR5380_read(STATUS_REG) & PHASE_MASK) == p && (p & SR_IO)) {
1248                         cnt = toPIO = atari_read_overruns;
1249                         if (overrun) {
1250                                 DMA_PRINTK("Got an input overrun, using saved byte\n");
1251                                 *(*data)++ = saved_data;
1252                                 (*count)--;
1253                                 cnt--;
1254                                 toPIO--;
1255                         }
1256                         DMA_PRINTK("Doing %d-byte PIO to 0x%08lx\n", cnt, (long)*data);
1257                         NCR5380_transfer_pio(instance, &p, &cnt, data);
1258                         *count -= toPIO - cnt;
1259                 }
1260         }
1261 }
1262 #endif /* REAL_DMA */
1263
1264
1265 /*
1266  * Function : void NCR5380_intr (int irq)
1267  *
1268  * Purpose : handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1269  *      from the disconnected queue, and restarting NCR5380_main()
1270  *      as required.
1271  *
1272  * Inputs : int irq, irq that caused this interrupt.
1273  *
1274  */
1275
1276 static irqreturn_t NCR5380_intr(int irq, void *dev_id)
1277 {
1278         struct Scsi_Host *instance = first_instance;
1279         int done = 1, handled = 0;
1280         unsigned char basr;
1281
1282         INT_PRINTK("scsi%d: NCR5380 irq triggered\n", HOSTNO);
1283
1284         /* Look for pending interrupts */
1285         basr = NCR5380_read(BUS_AND_STATUS_REG);
1286         INT_PRINTK("scsi%d: BASR=%02x\n", HOSTNO, basr);
1287         /* dispatch to appropriate routine if found and done=0 */
1288         if (basr & BASR_IRQ) {
1289                 NCR_PRINT(NDEBUG_INTR);
1290                 if ((NCR5380_read(STATUS_REG) & (SR_SEL|SR_IO)) == (SR_SEL|SR_IO)) {
1291                         done = 0;
1292                         ENABLE_IRQ();
1293                         INT_PRINTK("scsi%d: SEL interrupt\n", HOSTNO);
1294                         NCR5380_reselect(instance);
1295                         (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1296                 } else if (basr & BASR_PARITY_ERROR) {
1297                         INT_PRINTK("scsi%d: PARITY interrupt\n", HOSTNO);
1298                         (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1299                 } else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) {
1300                         INT_PRINTK("scsi%d: RESET interrupt\n", HOSTNO);
1301                         (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1302                 } else {
1303                         /*
1304                          * The rest of the interrupt conditions can occur only during a
1305                          * DMA transfer
1306                          */
1307
1308 #if defined(REAL_DMA)
1309                         /*
1310                          * We should only get PHASE MISMATCH and EOP interrupts if we have
1311                          * DMA enabled, so do a sanity check based on the current setting
1312                          * of the MODE register.
1313                          */
1314
1315                         if ((NCR5380_read(MODE_REG) & MR_DMA_MODE) &&
1316                             ((basr & BASR_END_DMA_TRANSFER) ||
1317                              !(basr & BASR_PHASE_MATCH))) {
1318
1319                                 INT_PRINTK("scsi%d: PHASE MISM or EOP interrupt\n", HOSTNO);
1320                                 NCR5380_dma_complete( instance );
1321                                 done = 0;
1322                                 ENABLE_IRQ();
1323                         } else
1324 #endif /* REAL_DMA */
1325                         {
1326 /* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */
1327                                 if (basr & BASR_PHASE_MATCH)
1328                                         printk(KERN_NOTICE "scsi%d: unknown interrupt, "
1329                                                "BASR 0x%x, MR 0x%x, SR 0x%x\n",
1330                                                HOSTNO, basr, NCR5380_read(MODE_REG),
1331                                                NCR5380_read(STATUS_REG));
1332                                 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1333                         }
1334                 } /* if !(SELECTION || PARITY) */
1335                 handled = 1;
1336         } /* BASR & IRQ */ else {
1337                 printk(KERN_NOTICE "scsi%d: interrupt without IRQ bit set in BASR, "
1338                        "BASR 0x%X, MR 0x%X, SR 0x%x\n", HOSTNO, basr,
1339                        NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG));
1340                 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1341         }
1342
1343         if (!done) {
1344                 INT_PRINTK("scsi%d: in int routine, calling main\n", HOSTNO);
1345                 /* Put a call to NCR5380_main() on the queue... */
1346                 queue_main();
1347         }
1348         return IRQ_RETVAL(handled);
1349 }
1350
1351 #ifdef NCR5380_STATS
1352 static void collect_stats(struct NCR5380_hostdata* hostdata, Scsi_Cmnd *cmd)
1353 {
1354 # ifdef NCR5380_STAT_LIMIT
1355         if (scsi_bufflen(cmd) > NCR5380_STAT_LIMIT)
1356 # endif
1357                 switch (cmd->cmnd[0]) {
1358                 case WRITE:
1359                 case WRITE_6:
1360                 case WRITE_10:
1361                         hostdata->time_write[cmd->device->id] += (jiffies - hostdata->timebase);
1362                         /*hostdata->bytes_write[cmd->device->id] += scsi_bufflen(cmd);*/
1363                         hostdata->pendingw--;
1364                         break;
1365                 case READ:
1366                 case READ_6:
1367                 case READ_10:
1368                         hostdata->time_read[cmd->device->id] += (jiffies - hostdata->timebase);
1369                         /*hostdata->bytes_read[cmd->device->id] += scsi_bufflen(cmd);*/
1370                         hostdata->pendingr--;
1371                         break;
1372                 }
1373 }
1374 #endif
1375
1376 /*
1377  * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd,
1378  *      int tag);
1379  *
1380  * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1381  *      including ARBITRATION, SELECTION, and initial message out for
1382  *      IDENTIFY and queue messages.
1383  *
1384  * Inputs : instance - instantiation of the 5380 driver on which this
1385  *      target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for
1386  *      new tag, TAG_NONE for untagged queueing, otherwise set to the tag for
1387  *      the command that is presently connected.
1388  *
1389  * Returns : -1 if selection could not execute for some reason,
1390  *      0 if selection succeeded or failed because the target
1391  *      did not respond.
1392  *
1393  * Side effects :
1394  *      If bus busy, arbitration failed, etc, NCR5380_select() will exit
1395  *              with registers as they should have been on entry - ie
1396  *              SELECT_ENABLE will be set appropriately, the NCR5380
1397  *              will cease to drive any SCSI bus signals.
1398  *
1399  *      If successful : I_T_L or I_T_L_Q nexus will be established,
1400  *              instance->connected will be set to cmd.
1401  *              SELECT interrupt will be disabled.
1402  *
1403  *      If failed (no target) : cmd->scsi_done() will be called, and the
1404  *              cmd->result host byte set to DID_BAD_TARGET.
1405  */
1406
1407 static int NCR5380_select(struct Scsi_Host *instance, Scsi_Cmnd *cmd, int tag)
1408 {
1409         SETUP_HOSTDATA(instance);
1410         unsigned char tmp[3], phase;
1411         unsigned char *data;
1412         int len;
1413         unsigned long timeout;
1414         unsigned long flags;
1415
1416         hostdata->restart_select = 0;
1417         NCR_PRINT(NDEBUG_ARBITRATION);
1418         ARB_PRINTK("scsi%d: starting arbitration, id = %d\n", HOSTNO,
1419                    instance->this_id);
1420
1421         /*
1422          * Set the phase bits to 0, otherwise the NCR5380 won't drive the
1423          * data bus during SELECTION.
1424          */
1425
1426         local_irq_save(flags);
1427         if (hostdata->connected) {
1428                 local_irq_restore(flags);
1429                 return -1;
1430         }
1431         NCR5380_write(TARGET_COMMAND_REG, 0);
1432
1433         /*
1434          * Start arbitration.
1435          */
1436
1437         NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
1438         NCR5380_write(MODE_REG, MR_ARBITRATE);
1439
1440         local_irq_restore(flags);
1441
1442         /* Wait for arbitration logic to complete */
1443 #if defined(NCR_TIMEOUT)
1444         {
1445                 unsigned long timeout = jiffies + 2*NCR_TIMEOUT;
1446
1447                 while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) &&
1448                        time_before(jiffies, timeout) && !hostdata->connected)
1449                         ;
1450                 if (time_after_eq(jiffies, timeout)) {
1451                         printk("scsi : arbitration timeout at %d\n", __LINE__);
1452                         NCR5380_write(MODE_REG, MR_BASE);
1453                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1454                         return -1;
1455                 }
1456         }
1457 #else /* NCR_TIMEOUT */
1458         while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) &&
1459                !hostdata->connected)
1460                 ;
1461 #endif
1462
1463         ARB_PRINTK("scsi%d: arbitration complete\n", HOSTNO);
1464
1465         if (hostdata->connected) {
1466                 NCR5380_write(MODE_REG, MR_BASE);
1467                 return -1;
1468         }
1469         /*
1470          * The arbitration delay is 2.2us, but this is a minimum and there is
1471          * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate
1472          * the integral nature of udelay().
1473          *
1474          */
1475
1476         udelay(3);
1477
1478         /* Check for lost arbitration */
1479         if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1480             (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) ||
1481             (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1482             hostdata->connected) {
1483                 NCR5380_write(MODE_REG, MR_BASE);
1484                 ARB_PRINTK("scsi%d: lost arbitration, deasserting MR_ARBITRATE\n",
1485                            HOSTNO);
1486                 return -1;
1487         }
1488
1489         /* after/during arbitration, BSY should be asserted.
1490            IBM DPES-31080 Version S31Q works now */
1491         /* Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman) */
1492         NCR5380_write(INITIATOR_COMMAND_REG,
1493                       ICR_BASE | ICR_ASSERT_SEL | ICR_ASSERT_BSY);
1494
1495         if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1496             hostdata->connected) {
1497                 NCR5380_write(MODE_REG, MR_BASE);
1498                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1499                 ARB_PRINTK("scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n",
1500                            HOSTNO);
1501                 return -1;
1502         }
1503
1504         /*
1505          * Again, bus clear + bus settle time is 1.2us, however, this is
1506          * a minimum so we'll udelay ceil(1.2)
1507          */
1508
1509 #ifdef CONFIG_ATARI_SCSI_TOSHIBA_DELAY
1510         /* ++roman: But some targets (see above :-) seem to need a bit more... */
1511         udelay(15);
1512 #else
1513         udelay(2);
1514 #endif
1515
1516         if (hostdata->connected) {
1517                 NCR5380_write(MODE_REG, MR_BASE);
1518                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1519                 return -1;
1520         }
1521
1522         ARB_PRINTK("scsi%d: won arbitration\n", HOSTNO);
1523
1524         /*
1525          * Now that we have won arbitration, start Selection process, asserting
1526          * the host and target ID's on the SCSI bus.
1527          */
1528
1529         NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << cmd->device->id)));
1530
1531         /*
1532          * Raise ATN while SEL is true before BSY goes false from arbitration,
1533          * since this is the only way to guarantee that we'll get a MESSAGE OUT
1534          * phase immediately after selection.
1535          */
1536
1537         NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY |
1538                       ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL ));
1539         NCR5380_write(MODE_REG, MR_BASE);
1540
1541         /*
1542          * Reselect interrupts must be turned off prior to the dropping of BSY,
1543          * otherwise we will trigger an interrupt.
1544          */
1545
1546         if (hostdata->connected) {
1547                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1548                 return -1;
1549         }
1550
1551         NCR5380_write(SELECT_ENABLE_REG, 0);
1552
1553         /*
1554          * The initiator shall then wait at least two deskew delays and release
1555          * the BSY signal.
1556          */
1557         udelay(1);        /* wingel -- wait two bus deskew delay >2*45ns */
1558
1559         /* Reset BSY */
1560         NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA |
1561                       ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1562
1563         /*
1564          * Something weird happens when we cease to drive BSY - looks
1565          * like the board/chip is letting us do another read before the
1566          * appropriate propagation delay has expired, and we're confusing
1567          * a BSY signal from ourselves as the target's response to SELECTION.
1568          *
1569          * A small delay (the 'C++' frontend breaks the pipeline with an
1570          * unnecessary jump, making it work on my 386-33/Trantor T128, the
1571          * tighter 'C' code breaks and requires this) solves the problem -
1572          * the 1 us delay is arbitrary, and only used because this delay will
1573          * be the same on other platforms and since it works here, it should
1574          * work there.
1575          *
1576          * wingel suggests that this could be due to failing to wait
1577          * one deskew delay.
1578          */
1579
1580         udelay(1);
1581
1582         SEL_PRINTK("scsi%d: selecting target %d\n", HOSTNO, cmd->device->id);
1583
1584         /*
1585          * The SCSI specification calls for a 250 ms timeout for the actual
1586          * selection.
1587          */
1588
1589         timeout = jiffies + 25;
1590
1591         /*
1592          * XXX very interesting - we're seeing a bounce where the BSY we
1593          * asserted is being reflected / still asserted (propagation delay?)
1594          * and it's detecting as true.  Sigh.
1595          */
1596
1597 #if 0
1598         /* ++roman: If a target conformed to the SCSI standard, it wouldn't assert
1599          * IO while SEL is true. But again, there are some disks out the in the
1600          * world that do that nevertheless. (Somebody claimed that this announces
1601          * reselection capability of the target.) So we better skip that test and
1602          * only wait for BSY... (Famous german words: Der Kl├╝gere gibt nach :-)
1603          */
1604
1605         while (time_before(jiffies, timeout) &&
1606                !(NCR5380_read(STATUS_REG) & (SR_BSY | SR_IO)))
1607                 ;
1608
1609         if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1610                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1611                 NCR5380_reselect(instance);
1612                 printk(KERN_ERR "scsi%d: reselection after won arbitration?\n",
1613                        HOSTNO);
1614                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1615                 return -1;
1616         }
1617 #else
1618         while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & SR_BSY))
1619                 ;
1620 #endif
1621
1622         /*
1623          * No less than two deskew delays after the initiator detects the
1624          * BSY signal is true, it shall release the SEL signal and may
1625          * change the DATA BUS.                                     -wingel
1626          */
1627
1628         udelay(1);
1629
1630         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1631
1632         if (!(NCR5380_read(STATUS_REG) & SR_BSY)) {
1633                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1634                 if (hostdata->targets_present & (1 << cmd->device->id)) {
1635                         printk(KERN_ERR "scsi%d: weirdness\n", HOSTNO);
1636                         if (hostdata->restart_select)
1637                                 printk(KERN_NOTICE "\trestart select\n");
1638                         NCR_PRINT(NDEBUG_ANY);
1639                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1640                         return -1;
1641                 }
1642                 cmd->result = DID_BAD_TARGET << 16;
1643 #ifdef NCR5380_STATS
1644                 collect_stats(hostdata, cmd);
1645 #endif
1646 #ifdef SUPPORT_TAGS
1647                 cmd_free_tag(cmd);
1648 #endif
1649                 cmd->scsi_done(cmd);
1650                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1651                 SEL_PRINTK("scsi%d: target did not respond within 250ms\n", HOSTNO);
1652                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1653                 return 0;
1654         }
1655
1656         hostdata->targets_present |= (1 << cmd->device->id);
1657
1658         /*
1659          * Since we followed the SCSI spec, and raised ATN while SEL
1660          * was true but before BSY was false during selection, the information
1661          * transfer phase should be a MESSAGE OUT phase so that we can send the
1662          * IDENTIFY message.
1663          *
1664          * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
1665          * message (2 bytes) with a tag ID that we increment with every command
1666          * until it wraps back to 0.
1667          *
1668          * XXX - it turns out that there are some broken SCSI-II devices,
1669          *           which claim to support tagged queuing but fail when more than
1670          *           some number of commands are issued at once.
1671          */
1672
1673         /* Wait for start of REQ/ACK handshake */
1674         while (!(NCR5380_read(STATUS_REG) & SR_REQ))
1675                 ;
1676
1677         SEL_PRINTK("scsi%d: target %d selected, going into MESSAGE OUT phase.\n",
1678                    HOSTNO, cmd->device->id);
1679         tmp[0] = IDENTIFY(1, cmd->device->lun);
1680
1681 #ifdef SUPPORT_TAGS
1682         if (cmd->tag != TAG_NONE) {
1683                 tmp[1] = hostdata->last_message = SIMPLE_QUEUE_TAG;
1684                 tmp[2] = cmd->tag;
1685                 len = 3;
1686         } else
1687                 len = 1;
1688 #else
1689         len = 1;
1690         cmd->tag = 0;
1691 #endif /* SUPPORT_TAGS */
1692
1693         /* Send message(s) */
1694         data = tmp;
1695         phase = PHASE_MSGOUT;
1696         NCR5380_transfer_pio(instance, &phase, &len, &data);
1697         SEL_PRINTK("scsi%d: nexus established.\n", HOSTNO);
1698         /* XXX need to handle errors here */
1699         hostdata->connected = cmd;
1700 #ifndef SUPPORT_TAGS
1701         hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
1702 #endif
1703
1704         initialize_SCp(cmd);
1705
1706         return 0;
1707 }
1708
1709 /*
1710  * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1711  *      unsigned char *phase, int *count, unsigned char **data)
1712  *
1713  * Purpose : transfers data in given phase using polled I/O
1714  *
1715  * Inputs : instance - instance of driver, *phase - pointer to
1716  *      what phase is expected, *count - pointer to number of
1717  *      bytes to transfer, **data - pointer to data pointer.
1718  *
1719  * Returns : -1 when different phase is entered without transferring
1720  *      maximum number of bytes, 0 if all bytes are transfered or exit
1721  *      is in same phase.
1722  *
1723  *      Also, *phase, *count, *data are modified in place.
1724  *
1725  * XXX Note : handling for bus free may be useful.
1726  */
1727
1728 /*
1729  * Note : this code is not as quick as it could be, however it
1730  * IS 100% reliable, and for the actual data transfer where speed
1731  * counts, we will always do a pseudo DMA or DMA transfer.
1732  */
1733
1734 static int NCR5380_transfer_pio(struct Scsi_Host *instance,
1735                                 unsigned char *phase, int *count,
1736                                 unsigned char **data)
1737 {
1738         register unsigned char p = *phase, tmp;
1739         register int c = *count;
1740         register unsigned char *d = *data;
1741
1742         /*
1743          * The NCR5380 chip will only drive the SCSI bus when the
1744          * phase specified in the appropriate bits of the TARGET COMMAND
1745          * REGISTER match the STATUS REGISTER
1746          */
1747
1748         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1749
1750         do {
1751                 /*
1752                  * Wait for assertion of REQ, after which the phase bits will be
1753                  * valid
1754                  */
1755                 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ))
1756                         ;
1757
1758                 HSH_PRINTK("scsi%d: REQ detected\n", HOSTNO);
1759
1760                 /* Check for phase mismatch */
1761                 if ((tmp & PHASE_MASK) != p) {
1762                         PIO_PRINTK("scsi%d: phase mismatch\n", HOSTNO);
1763                         NCR_PRINT_PHASE(NDEBUG_PIO);
1764                         break;
1765                 }
1766
1767                 /* Do actual transfer from SCSI bus to / from memory */
1768                 if (!(p & SR_IO))
1769                         NCR5380_write(OUTPUT_DATA_REG, *d);
1770                 else
1771                         *d = NCR5380_read(CURRENT_SCSI_DATA_REG);
1772
1773                 ++d;
1774
1775                 /*
1776                  * The SCSI standard suggests that in MSGOUT phase, the initiator
1777                  * should drop ATN on the last byte of the message phase
1778                  * after REQ has been asserted for the handshake but before
1779                  * the initiator raises ACK.
1780                  */
1781
1782                 if (!(p & SR_IO)) {
1783                         if (!((p & SR_MSG) && c > 1)) {
1784                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1785                                 NCR_PRINT(NDEBUG_PIO);
1786                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1787                                               ICR_ASSERT_DATA | ICR_ASSERT_ACK);
1788                         } else {
1789                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1790                                               ICR_ASSERT_DATA | ICR_ASSERT_ATN);
1791                                 NCR_PRINT(NDEBUG_PIO);
1792                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1793                                               ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1794                         }
1795                 } else {
1796                         NCR_PRINT(NDEBUG_PIO);
1797                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
1798                 }
1799
1800                 while (NCR5380_read(STATUS_REG) & SR_REQ)
1801                         ;
1802
1803                 HSH_PRINTK("scsi%d: req false, handshake complete\n", HOSTNO);
1804
1805                 /*
1806                  * We have several special cases to consider during REQ/ACK handshaking :
1807                  * 1.  We were in MSGOUT phase, and we are on the last byte of the
1808                  *      message.  ATN must be dropped as ACK is dropped.
1809                  *
1810                  * 2.  We are in a MSGIN phase, and we are on the last byte of the
1811                  *      message.  We must exit with ACK asserted, so that the calling
1812                  *      code may raise ATN before dropping ACK to reject the message.
1813                  *
1814                  * 3.  ACK and ATN are clear and the target may proceed as normal.
1815                  */
1816                 if (!(p == PHASE_MSGIN && c == 1)) {
1817                         if (p == PHASE_MSGOUT && c > 1)
1818                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1819                         else
1820                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1821                 }
1822         } while (--c);
1823
1824         PIO_PRINTK("scsi%d: residual %d\n", HOSTNO, c);
1825
1826         *count = c;
1827         *data = d;
1828         tmp = NCR5380_read(STATUS_REG);
1829         /* The phase read from the bus is valid if either REQ is (already)
1830          * asserted or if ACK hasn't been released yet. The latter is the case if
1831          * we're in MSGIN and all wanted bytes have been received.
1832          */
1833         if ((tmp & SR_REQ) || (p == PHASE_MSGIN && c == 0))
1834                 *phase = tmp & PHASE_MASK;
1835         else
1836                 *phase = PHASE_UNKNOWN;
1837
1838         if (!c || (*phase == p))
1839                 return 0;
1840         else
1841                 return -1;
1842 }
1843
1844 /*
1845  * Function : do_abort (Scsi_Host *host)
1846  *
1847  * Purpose : abort the currently established nexus.  Should only be
1848  *      called from a routine which can drop into a
1849  *
1850  * Returns : 0 on success, -1 on failure.
1851  */
1852
1853 static int do_abort(struct Scsi_Host *host)
1854 {
1855         unsigned char tmp, *msgptr, phase;
1856         int len;
1857
1858         /* Request message out phase */
1859         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1860
1861         /*
1862          * Wait for the target to indicate a valid phase by asserting
1863          * REQ.  Once this happens, we'll have either a MSGOUT phase
1864          * and can immediately send the ABORT message, or we'll have some
1865          * other phase and will have to source/sink data.
1866          *
1867          * We really don't care what value was on the bus or what value
1868          * the target sees, so we just handshake.
1869          */
1870
1871         while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ))
1872                 ;
1873
1874         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
1875
1876         if ((tmp & PHASE_MASK) != PHASE_MSGOUT) {
1877                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
1878                               ICR_ASSERT_ACK);
1879                 while (NCR5380_read(STATUS_REG) & SR_REQ)
1880                         ;
1881                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1882         }
1883
1884         tmp = ABORT;
1885         msgptr = &tmp;
1886         len = 1;
1887         phase = PHASE_MSGOUT;
1888         NCR5380_transfer_pio(host, &phase, &len, &msgptr);
1889
1890         /*
1891          * If we got here, and the command completed successfully,
1892          * we're about to go into bus free state.
1893          */
1894
1895         return len ? -1 : 0;
1896 }
1897
1898 #if defined(REAL_DMA)
1899 /*
1900  * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1901  *      unsigned char *phase, int *count, unsigned char **data)
1902  *
1903  * Purpose : transfers data in given phase using either real
1904  *      or pseudo DMA.
1905  *
1906  * Inputs : instance - instance of driver, *phase - pointer to
1907  *      what phase is expected, *count - pointer to number of
1908  *      bytes to transfer, **data - pointer to data pointer.
1909  *
1910  * Returns : -1 when different phase is entered without transferring
1911  *      maximum number of bytes, 0 if all bytes or transfered or exit
1912  *      is in same phase.
1913  *
1914  *      Also, *phase, *count, *data are modified in place.
1915  *
1916  */
1917
1918
1919 static int NCR5380_transfer_dma(struct Scsi_Host *instance,
1920                                 unsigned char *phase, int *count,
1921                                 unsigned char **data)
1922 {
1923         SETUP_HOSTDATA(instance);
1924         register int c = *count;
1925         register unsigned char p = *phase;
1926         register unsigned char *d = *data;
1927         unsigned char tmp;
1928         unsigned long flags;
1929
1930         if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
1931                 *phase = tmp;
1932                 return -1;
1933         }
1934
1935         if (atari_read_overruns && (p & SR_IO))
1936                 c -= atari_read_overruns;
1937
1938         DMA_PRINTK("scsi%d: initializing DMA for %s, %d bytes %s %p\n",
1939                    HOSTNO, (p & SR_IO) ? "reading" : "writing",
1940                    c, (p & SR_IO) ? "to" : "from", d);
1941
1942         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1943
1944 #ifdef REAL_DMA
1945         NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
1946 #endif /* def REAL_DMA  */
1947
1948         if (IS_A_TT()) {
1949                 /* On the Medusa, it is a must to initialize the DMA before
1950                  * starting the NCR. This is also the cleaner way for the TT.
1951                  */
1952                 local_irq_save(flags);
1953                 hostdata->dma_len = (p & SR_IO) ?
1954                         NCR5380_dma_read_setup(instance, d, c) :
1955                         NCR5380_dma_write_setup(instance, d, c);
1956                 local_irq_restore(flags);
1957         }
1958
1959         if (p & SR_IO)
1960                 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
1961         else {
1962                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1963                 NCR5380_write(START_DMA_SEND_REG, 0);
1964         }
1965
1966         if (!IS_A_TT()) {
1967                 /* On the Falcon, the DMA setup must be done after the last */
1968                 /* NCR access, else the DMA setup gets trashed!
1969                  */
1970                 local_irq_save(flags);
1971                 hostdata->dma_len = (p & SR_IO) ?
1972                         NCR5380_dma_read_setup(instance, d, c) :
1973                         NCR5380_dma_write_setup(instance, d, c);
1974                 local_irq_restore(flags);
1975         }
1976         return 0;
1977 }
1978 #endif /* defined(REAL_DMA) */
1979
1980 /*
1981  * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
1982  *
1983  * Purpose : run through the various SCSI phases and do as the target
1984  *      directs us to.  Operates on the currently connected command,
1985  *      instance->connected.
1986  *
1987  * Inputs : instance, instance for which we are doing commands
1988  *
1989  * Side effects : SCSI things happen, the disconnected queue will be
1990  *      modified if a command disconnects, *instance->connected will
1991  *      change.
1992  *
1993  * XXX Note : we need to watch for bus free or a reset condition here
1994  *      to recover from an unexpected bus free condition.
1995  */
1996
1997 static void NCR5380_information_transfer(struct Scsi_Host *instance)
1998 {
1999         SETUP_HOSTDATA(instance);
2000         unsigned long flags;
2001         unsigned char msgout = NOP;
2002         int sink = 0;
2003         int len;
2004 #if defined(REAL_DMA)
2005         int transfersize;
2006 #endif
2007         unsigned char *data;
2008         unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
2009         Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected;
2010
2011         while (1) {
2012                 tmp = NCR5380_read(STATUS_REG);
2013                 /* We only have a valid SCSI phase when REQ is asserted */
2014                 if (tmp & SR_REQ) {
2015                         phase = (tmp & PHASE_MASK);
2016                         if (phase != old_phase) {
2017                                 old_phase = phase;
2018                                 NCR_PRINT_PHASE(NDEBUG_INFORMATION);
2019                         }
2020
2021                         if (sink && (phase != PHASE_MSGOUT)) {
2022                                 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
2023
2024                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
2025                                               ICR_ASSERT_ACK);
2026                                 while (NCR5380_read(STATUS_REG) & SR_REQ)
2027                                         ;
2028                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
2029                                               ICR_ASSERT_ATN);
2030                                 sink = 0;
2031                                 continue;
2032                         }
2033
2034                         switch (phase) {
2035                         case PHASE_DATAOUT:
2036 #if (NDEBUG & NDEBUG_NO_DATAOUT)
2037                                 printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT "
2038                                        "aborted\n", HOSTNO);
2039                                 sink = 1;
2040                                 do_abort(instance);
2041                                 cmd->result = DID_ERROR << 16;
2042                                 cmd->scsi_done(cmd);
2043                                 return;
2044 #endif
2045                         case PHASE_DATAIN:
2046                                 /*
2047                                  * If there is no room left in the current buffer in the
2048                                  * scatter-gather list, move onto the next one.
2049                                  */
2050
2051                                 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
2052                                         ++cmd->SCp.buffer;
2053                                         --cmd->SCp.buffers_residual;
2054                                         cmd->SCp.this_residual = cmd->SCp.buffer->length;
2055                                         cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
2056                                         /* ++roman: Try to merge some scatter-buffers if
2057                                          * they are at contiguous physical addresses.
2058                                          */
2059                                         merge_contiguous_buffers(cmd);
2060                                         INF_PRINTK("scsi%d: %d bytes and %d buffers left\n",
2061                                                    HOSTNO, cmd->SCp.this_residual,
2062                                                    cmd->SCp.buffers_residual);
2063                                 }
2064
2065                                 /*
2066                                  * The preferred transfer method is going to be
2067                                  * PSEUDO-DMA for systems that are strictly PIO,
2068                                  * since we can let the hardware do the handshaking.
2069                                  *
2070                                  * For this to work, we need to know the transfersize
2071                                  * ahead of time, since the pseudo-DMA code will sit
2072                                  * in an unconditional loop.
2073                                  */
2074
2075                                 /* ++roman: I suggest, this should be
2076                                  *   #if def(REAL_DMA)
2077                                  * instead of leaving REAL_DMA out.
2078                                  */
2079
2080 #if defined(REAL_DMA)
2081                                 if (!cmd->device->borken &&
2082                                     (transfersize = NCR5380_dma_xfer_len(instance,cmd,phase)) > 31) {
2083                                         len = transfersize;
2084                                         cmd->SCp.phase = phase;
2085                                         if (NCR5380_transfer_dma(instance, &phase,
2086                                             &len, (unsigned char **)&cmd->SCp.ptr)) {
2087                                                 /*
2088                                                  * If the watchdog timer fires, all future
2089                                                  * accesses to this device will use the
2090                                                  * polled-IO. */
2091                                                 printk(KERN_NOTICE "scsi%d: switching target %d "
2092                                                            "lun %d to slow handshake\n", HOSTNO,
2093                                                            cmd->device->id, cmd->device->lun);
2094                                                 cmd->device->borken = 1;
2095                                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
2096                                                         ICR_ASSERT_ATN);
2097                                                 sink = 1;
2098                                                 do_abort(instance);
2099                                                 cmd->result = DID_ERROR << 16;
2100                                                 cmd->scsi_done(cmd);
2101                                                 /* XXX - need to source or sink data here, as appropriate */
2102                                         } else {
2103 #ifdef REAL_DMA
2104                                                 /* ++roman: When using real DMA,
2105                                                  * information_transfer() should return after
2106                                                  * starting DMA since it has nothing more to
2107                                                  * do.
2108                                                  */
2109                                                 return;
2110 #else
2111                                                 cmd->SCp.this_residual -= transfersize - len;
2112 #endif
2113                                         }
2114                                 } else
2115 #endif /* defined(REAL_DMA) */
2116                                         NCR5380_transfer_pio(instance, &phase,
2117                                                              (int *)&cmd->SCp.this_residual,
2118                                                              (unsigned char **)&cmd->SCp.ptr);
2119                                 break;
2120                         case PHASE_MSGIN:
2121                                 len = 1;
2122                                 data = &tmp;
2123                                 NCR5380_write(SELECT_ENABLE_REG, 0);    /* disable reselects */
2124                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2125                                 cmd->SCp.Message = tmp;
2126
2127                                 switch (tmp) {
2128                                 /*
2129                                  * Linking lets us reduce the time required to get the
2130                                  * next command out to the device, hopefully this will
2131                                  * mean we don't waste another revolution due to the delays
2132                                  * required by ARBITRATION and another SELECTION.
2133                                  *
2134                                  * In the current implementation proposal, low level drivers
2135                                  * merely have to start the next command, pointed to by
2136                                  * next_link, done() is called as with unlinked commands.
2137                                  */
2138 #ifdef LINKED
2139                                 case LINKED_CMD_COMPLETE:
2140                                 case LINKED_FLG_CMD_COMPLETE:
2141                                         /* Accept message by clearing ACK */
2142                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2143
2144                                         LNK_PRINTK("scsi%d: target %d lun %d linked command "
2145                                                    "complete.\n", HOSTNO, cmd->device->id, cmd->device->lun);
2146
2147                                         /* Enable reselect interrupts */
2148                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2149                                         /*
2150                                          * Sanity check : A linked command should only terminate
2151                                          * with one of these messages if there are more linked
2152                                          * commands available.
2153                                          */
2154
2155                                         if (!cmd->next_link) {
2156                                                  printk(KERN_NOTICE "scsi%d: target %d lun %d "
2157                                                         "linked command complete, no next_link\n",
2158                                                         HOSTNO, cmd->device->id, cmd->device->lun);
2159                                                 sink = 1;
2160                                                 do_abort(instance);
2161                                                 return;
2162                                         }
2163
2164                                         initialize_SCp(cmd->next_link);
2165                                         /* The next command is still part of this process; copy it
2166                                          * and don't free it! */
2167                                         cmd->next_link->tag = cmd->tag;
2168                                         cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2169                                         LNK_PRINTK("scsi%d: target %d lun %d linked request "
2170                                                    "done, calling scsi_done().\n",
2171                                                    HOSTNO, cmd->device->id, cmd->device->lun);
2172 #ifdef NCR5380_STATS
2173                                         collect_stats(hostdata, cmd);
2174 #endif
2175                                         cmd->scsi_done(cmd);
2176                                         cmd = hostdata->connected;
2177                                         break;
2178 #endif /* def LINKED */
2179                                 case ABORT:
2180                                 case COMMAND_COMPLETE:
2181                                         /* Accept message by clearing ACK */
2182                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2183                                         /* ++guenther: possible race with Falcon locking */
2184                                         falcon_dont_release++;
2185                                         hostdata->connected = NULL;
2186                                         QU_PRINTK("scsi%d: command for target %d, lun %d "
2187                                                   "completed\n", HOSTNO, cmd->device->id, cmd->device->lun);
2188 #ifdef SUPPORT_TAGS
2189                                         cmd_free_tag(cmd);
2190                                         if (status_byte(cmd->SCp.Status) == QUEUE_FULL) {
2191                                                 /* Turn a QUEUE FULL status into BUSY, I think the
2192                                                  * mid level cannot handle QUEUE FULL :-( (The
2193                                                  * command is retried after BUSY). Also update our
2194                                                  * queue size to the number of currently issued
2195                                                  * commands now.
2196                                                  */
2197                                                 /* ++Andreas: the mid level code knows about
2198                                                    QUEUE_FULL now. */
2199                                                 TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun];
2200                                                 TAG_PRINTK("scsi%d: target %d lun %d returned "
2201                                                            "QUEUE_FULL after %d commands\n",
2202                                                            HOSTNO, cmd->device->id, cmd->device->lun,
2203                                                            ta->nr_allocated);
2204                                                 if (ta->queue_size > ta->nr_allocated)
2205                                                         ta->nr_allocated = ta->queue_size;
2206                                         }
2207 #else
2208                                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2209 #endif
2210                                         /* Enable reselect interrupts */
2211                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2212
2213                                         /*
2214                                          * I'm not sure what the correct thing to do here is :
2215                                          *
2216                                          * If the command that just executed is NOT a request
2217                                          * sense, the obvious thing to do is to set the result
2218                                          * code to the values of the stored parameters.
2219                                          *
2220                                          * If it was a REQUEST SENSE command, we need some way to
2221                                          * differentiate between the failure code of the original
2222                                          * and the failure code of the REQUEST sense - the obvious
2223                                          * case is success, where we fall through and leave the
2224                                          * result code unchanged.
2225                                          *
2226                                          * The non-obvious place is where the REQUEST SENSE failed
2227                                          */
2228
2229                                         if (cmd->cmnd[0] != REQUEST_SENSE)
2230                                                 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2231                                         else if (status_byte(cmd->SCp.Status) != GOOD)
2232                                                 cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16);
2233
2234 #ifdef AUTOSENSE
2235                                         if ((cmd->cmnd[0] == REQUEST_SENSE) &&
2236                                                 hostdata->ses.cmd_len) {
2237                                                 scsi_eh_restore_cmnd(cmd, &hostdata->ses);
2238                                                 hostdata->ses.cmd_len = 0 ;
2239                                         }
2240
2241                                         if ((cmd->cmnd[0] != REQUEST_SENSE) &&
2242                                             (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
2243                                                 scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);
2244
2245                                                 ASEN_PRINTK("scsi%d: performing request sense\n", HOSTNO);
2246
2247                                                 local_irq_save(flags);
2248                                                 LIST(cmd,hostdata->issue_queue);
2249                                                 SET_NEXT(cmd, hostdata->issue_queue);
2250                                                 hostdata->issue_queue = (Scsi_Cmnd *) cmd;
2251                                                 local_irq_restore(flags);
2252                                                 QU_PRINTK("scsi%d: REQUEST SENSE added to head of "
2253                                                           "issue queue\n", H_NO(cmd));
2254                                         } else
2255 #endif /* def AUTOSENSE */
2256                                         {
2257 #ifdef NCR5380_STATS
2258                                                 collect_stats(hostdata, cmd);
2259 #endif
2260                                                 cmd->scsi_done(cmd);
2261                                         }
2262
2263                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2264                                         /*
2265                                          * Restore phase bits to 0 so an interrupted selection,
2266                                          * arbitration can resume.
2267                                          */
2268                                         NCR5380_write(TARGET_COMMAND_REG, 0);
2269
2270                                         while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2271                                                 barrier();
2272
2273                                         falcon_dont_release--;
2274                                         /* ++roman: For Falcon SCSI, release the lock on the
2275                                          * ST-DMA here if no other commands are waiting on the
2276                                          * disconnected queue.
2277                                          */
2278                                         falcon_release_lock_if_possible(hostdata);
2279                                         return;
2280                                 case MESSAGE_REJECT:
2281                                         /* Accept message by clearing ACK */
2282                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2283                                         /* Enable reselect interrupts */
2284                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2285                                         switch (hostdata->last_message) {
2286                                         case HEAD_OF_QUEUE_TAG:
2287                                         case ORDERED_QUEUE_TAG:
2288                                         case SIMPLE_QUEUE_TAG:
2289                                                 /* The target obviously doesn't support tagged
2290                                                  * queuing, even though it announced this ability in
2291                                                  * its INQUIRY data ?!? (maybe only this LUN?) Ok,
2292                                                  * clear 'tagged_supported' and lock the LUN, since
2293                                                  * the command is treated as untagged further on.
2294                                                  */
2295                                                 cmd->device->tagged_supported = 0;
2296                                                 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
2297                                                 cmd->tag = TAG_NONE;
2298                                                 TAG_PRINTK("scsi%d: target %d lun %d rejected "
2299                                                            "QUEUE_TAG message; tagged queuing "
2300                                                            "disabled\n",
2301                                                            HOSTNO, cmd->device->id, cmd->device->lun);
2302                                                 break;
2303                                         }
2304                                         break;
2305                                 case DISCONNECT:
2306                                         /* Accept message by clearing ACK */
2307                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2308                                         local_irq_save(flags);
2309                                         cmd->device->disconnect = 1;
2310                                         LIST(cmd,hostdata->disconnected_queue);
2311                                         SET_NEXT(cmd, hostdata->disconnected_queue);
2312                                         hostdata->connected = NULL;
2313                                         hostdata->disconnected_queue = cmd;
2314                                         local_irq_restore(flags);
2315                                         QU_PRINTK("scsi%d: command for target %d lun %d was "
2316                                                   "moved from connected to the "
2317                                                   "disconnected_queue\n", HOSTNO,
2318                                                   cmd->device->id, cmd->device->lun);
2319                                         /*
2320                                          * Restore phase bits to 0 so an interrupted selection,
2321                                          * arbitration can resume.
2322                                          */
2323                                         NCR5380_write(TARGET_COMMAND_REG, 0);
2324
2325                                         /* Enable reselect interrupts */
2326                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2327                                         /* Wait for bus free to avoid nasty timeouts */
2328                                         while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2329                                                 barrier();
2330                                         return;
2331                                         /*
2332                                          * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
2333                                          * operation, in violation of the SCSI spec so we can safely
2334                                          * ignore SAVE/RESTORE pointers calls.
2335                                          *
2336                                          * Unfortunately, some disks violate the SCSI spec and
2337                                          * don't issue the required SAVE_POINTERS message before
2338                                          * disconnecting, and we have to break spec to remain
2339                                          * compatible.
2340                                          */
2341                                 case SAVE_POINTERS:
2342                                 case RESTORE_POINTERS:
2343                                         /* Accept message by clearing ACK */
2344                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2345                                         /* Enable reselect interrupts */
2346                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2347                                         break;
2348                                 case EXTENDED_MESSAGE:
2349                                         /*
2350                                          * Extended messages are sent in the following format :
2351                                          * Byte
2352                                          * 0            EXTENDED_MESSAGE == 1
2353                                          * 1            length (includes one byte for code, doesn't
2354                                          *              include first two bytes)
2355                                          * 2            code
2356                                          * 3..length+1  arguments
2357                                          *
2358                                          * Start the extended message buffer with the EXTENDED_MESSAGE
2359                                          * byte, since spi_print_msg() wants the whole thing.
2360                                          */
2361                                         extended_msg[0] = EXTENDED_MESSAGE;
2362                                         /* Accept first byte by clearing ACK */
2363                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2364
2365                                         EXT_PRINTK("scsi%d: receiving extended message\n", HOSTNO);
2366
2367                                         len = 2;
2368                                         data = extended_msg + 1;
2369                                         phase = PHASE_MSGIN;
2370                                         NCR5380_transfer_pio(instance, &phase, &len, &data);
2371                                         EXT_PRINTK("scsi%d: length=%d, code=0x%02x\n", HOSTNO,
2372                                                    (int)extended_msg[1], (int)extended_msg[2]);
2373
2374                                         if (!len && extended_msg[1] <=
2375                                             (sizeof(extended_msg) - 1)) {
2376                                                 /* Accept third byte by clearing ACK */
2377                                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2378                                                 len = extended_msg[1] - 1;
2379                                                 data = extended_msg + 3;
2380                                                 phase = PHASE_MSGIN;
2381
2382                                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2383                                                 EXT_PRINTK("scsi%d: message received, residual %d\n",
2384                                                            HOSTNO, len);
2385
2386                                                 switch (extended_msg[2]) {
2387                                                 case EXTENDED_SDTR:
2388                                                 case EXTENDED_WDTR:
2389                                                 case EXTENDED_MODIFY_DATA_POINTER:
2390                                                 case EXTENDED_EXTENDED_IDENTIFY:
2391                                                         tmp = 0;
2392                                                 }
2393                                         } else if (len) {
2394                                                 printk(KERN_NOTICE "scsi%d: error receiving "
2395                                                        "extended message\n", HOSTNO);
2396                                                 tmp = 0;
2397                                         } else {
2398                                                 printk(KERN_NOTICE "scsi%d: extended message "
2399                                                            "code %02x length %d is too long\n",
2400                                                            HOSTNO, extended_msg[2], extended_msg[1]);
2401                                                 tmp = 0;
2402                                         }
2403                                         /* Fall through to reject message */
2404
2405                                         /*
2406                                          * If we get something weird that we aren't expecting,
2407                                          * reject it.
2408                                          */
2409                                 default:
2410                                         if (!tmp) {
2411                                                 printk(KERN_DEBUG "scsi%d: rejecting message ", HOSTNO);
2412                                                 spi_print_msg(extended_msg);
2413                                                 printk("\n");
2414                                         } else if (tmp != EXTENDED_MESSAGE)
2415                                                 printk(KERN_DEBUG "scsi%d: rejecting unknown "
2416                                                        "message %02x from target %d, lun %d\n",
2417                                                        HOSTNO, tmp, cmd->device->id, cmd->device->lun);
2418                                         else
2419                                                 printk(KERN_DEBUG "scsi%d: rejecting unknown "
2420                                                        "extended message "
2421                                                        "code %02x, length %d from target %d, lun %d\n",
2422                                                        HOSTNO, extended_msg[1], extended_msg[0],
2423                                                        cmd->device->id, cmd->device->lun);
2424
2425
2426                                         msgout = MESSAGE_REJECT;
2427                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2428                                         break;
2429                                 } /* switch (tmp) */
2430                                 break;
2431                         case PHASE_MSGOUT:
2432                                 len = 1;
2433                                 data = &msgout;
2434                                 hostdata->last_message = msgout;
2435                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2436                                 if (msgout == ABORT) {
2437 #ifdef SUPPORT_TAGS
2438                                         cmd_free_tag(cmd);
2439 #else
2440                                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2441 #endif
2442                                         hostdata->connected = NULL;
2443                                         cmd->result = DID_ERROR << 16;
2444 #ifdef NCR5380_STATS
2445                                         collect_stats(hostdata, cmd);
2446 #endif
2447                                         cmd->scsi_done(cmd);
2448                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2449                                         falcon_release_lock_if_possible(hostdata);
2450                                         return;
2451                                 }
2452                                 msgout = NOP;
2453                                 break;
2454                         case PHASE_CMDOUT:
2455                                 len = cmd->cmd_len;
2456                                 data = cmd->cmnd;
2457                                 /*
2458                                  * XXX for performance reasons, on machines with a
2459                                  * PSEUDO-DMA architecture we should probably
2460                                  * use the dma transfer function.
2461                                  */
2462                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2463                                 break;
2464                         case PHASE_STATIN:
2465                                 len = 1;
2466                                 data = &tmp;
2467                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2468                                 cmd->SCp.Status = tmp;
2469                                 break;
2470                         default:
2471                                 printk("scsi%d: unknown phase\n", HOSTNO);
2472                                 NCR_PRINT(NDEBUG_ANY);
2473                         } /* switch(phase) */
2474                 } /* if (tmp * SR_REQ) */
2475         } /* while (1) */
2476 }
2477
2478 /*
2479  * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2480  *
2481  * Purpose : does reselection, initializing the instance->connected
2482  *      field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q
2483  *      nexus has been reestablished,
2484  *
2485  * Inputs : instance - this instance of the NCR5380.
2486  *
2487  */
2488
2489
2490 static void NCR5380_reselect(struct Scsi_Host *instance)
2491 {
2492         SETUP_HOSTDATA(instance);
2493         unsigned char target_mask;
2494         unsigned char lun, phase;
2495         int len;
2496 #ifdef SUPPORT_TAGS
2497         unsigned char tag;
2498 #endif
2499         unsigned char msg[3];
2500         unsigned char *data;
2501         Scsi_Cmnd *tmp = NULL, *prev;
2502 /*      unsigned long flags; */
2503
2504         /*
2505          * Disable arbitration, etc. since the host adapter obviously
2506          * lost, and tell an interrupted NCR5380_select() to restart.
2507          */
2508
2509         NCR5380_write(MODE_REG, MR_BASE);
2510         hostdata->restart_select = 1;
2511
2512         target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
2513
2514         RSL_PRINTK("scsi%d: reselect\n", HOSTNO);
2515
2516         /*
2517          * At this point, we have detected that our SCSI ID is on the bus,
2518          * SEL is true and BSY was false for at least one bus settle delay
2519          * (400 ns).
2520          *
2521          * We must assert BSY ourselves, until the target drops the SEL
2522          * signal.
2523          */
2524
2525         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY);
2526
2527         while (NCR5380_read(STATUS_REG) & SR_SEL)
2528                 ;
2529         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2530
2531         /*
2532          * Wait for target to go into MSGIN.
2533          */
2534
2535         while (!(NCR5380_read(STATUS_REG) & SR_REQ))
2536                 ;
2537
2538         len = 1;
2539         data = msg;
2540         phase = PHASE_MSGIN;
2541         NCR5380_transfer_pio(instance, &phase, &len, &data);
2542
2543         if (!(msg[0] & 0x80)) {
2544                 printk(KERN_DEBUG "scsi%d: expecting IDENTIFY message, got ", HOSTNO);
2545                 spi_print_msg(msg);
2546                 do_abort(instance);
2547                 return;
2548         }
2549         lun = (msg[0] & 0x07);
2550
2551 #ifdef SUPPORT_TAGS
2552         /* If the phase is still MSGIN, the target wants to send some more
2553          * messages. In case it supports tagged queuing, this is probably a
2554          * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus.
2555          */
2556         tag = TAG_NONE;
2557         if (phase == PHASE_MSGIN && setup_use_tagged_queuing) {
2558                 /* Accept previous IDENTIFY message by clearing ACK */
2559                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2560                 len = 2;
2561                 data = msg + 1;
2562                 if (!NCR5380_transfer_pio(instance, &phase, &len, &data) &&
2563                     msg[1] == SIMPLE_QUEUE_TAG)
2564                         tag = msg[2];
2565                 TAG_PRINTK("scsi%d: target mask %02x, lun %d sent tag %d at "
2566                            "reselection\n", HOSTNO, target_mask, lun, tag);
2567         }
2568 #endif
2569
2570         /*
2571          * Find the command corresponding to the I_T_L or I_T_L_Q  nexus we
2572          * just reestablished, and remove it from the disconnected queue.
2573          */
2574
2575         for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL;
2576              tmp; prev = tmp, tmp = NEXT(tmp)) {
2577                 if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun)
2578 #ifdef SUPPORT_TAGS
2579                     && (tag == tmp->tag)
2580 #endif
2581                     ) {
2582                         /* ++guenther: prevent race with falcon_release_lock */
2583                         falcon_dont_release++;
2584                         if (prev) {
2585                                 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
2586                                 SET_NEXT(prev, NEXT(tmp));
2587                         } else {
2588                                 REMOVE(-1, hostdata->disconnected_queue, tmp, NEXT(tmp));
2589                                 hostdata->disconnected_queue = NEXT(tmp);
2590                         }
2591                         SET_NEXT(tmp, NULL);
2592                         break;
2593                 }
2594         }
2595
2596         if (!tmp) {
2597                 printk(KERN_WARNING "scsi%d: warning: target bitmask %02x lun %d "
2598 #ifdef SUPPORT_TAGS
2599                        "tag %d "
2600 #endif
2601                        "not in disconnected_queue.\n",
2602                        HOSTNO, target_mask, lun
2603 #ifdef SUPPORT_TAGS
2604                        , tag
2605 #endif
2606                         );
2607                 /*
2608                  * Since we have an established nexus that we can't do anything
2609                  * with, we must abort it.
2610                  */
2611                 do_abort(instance);
2612                 return;
2613         }
2614
2615         /* Accept message by clearing ACK */
2616         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2617
2618         hostdata->connected = tmp;
2619         RSL_PRINTK("scsi%d: nexus established, target = %d, lun = %d, tag = %d\n",
2620                    HOSTNO, tmp->device->id, tmp->device->lun, tmp->tag);
2621         falcon_dont_release--;
2622 }
2623
2624
2625 /*
2626  * Function : int NCR5380_abort (Scsi_Cmnd *cmd)
2627  *
2628  * Purpose : abort a command
2629  *
2630  * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the
2631  *      host byte of the result field to, if zero DID_ABORTED is
2632  *      used.
2633  *
2634  * Returns : 0 - success, -1 on failure.
2635  *
2636  * XXX - there is no way to abort the command that is currently
2637  *       connected, you have to wait for it to complete.  If this is
2638  *       a problem, we could implement longjmp() / setjmp(), setjmp()
2639  *       called where the loop started in NCR5380_main().
2640  */
2641
2642 static
2643 int NCR5380_abort(Scsi_Cmnd *cmd)
2644 {
2645         struct Scsi_Host *instance = cmd->device->host;
2646         SETUP_HOSTDATA(instance);
2647         Scsi_Cmnd *tmp, **prev;
2648         unsigned long flags;
2649
2650         printk(KERN_NOTICE "scsi%d: aborting command\n", HOSTNO);
2651         scsi_print_command(cmd);
2652
2653         NCR5380_print_status(instance);
2654
2655         local_irq_save(flags);
2656
2657         if (!IS_A_TT() && !falcon_got_lock)
2658                 printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_abort\n",
2659                        HOSTNO);
2660
2661         ABRT_PRINTK("scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO,
2662                     NCR5380_read(BUS_AND_STATUS_REG),
2663                     NCR5380_read(STATUS_REG));
2664
2665 #if 1
2666         /*
2667          * Case 1 : If the command is the currently executing command,
2668          * we'll set the aborted flag and return control so that
2669          * information transfer routine can exit cleanly.
2670          */
2671
2672         if (hostdata->connected == cmd) {
2673
2674                 ABRT_PRINTK("scsi%d: aborting connected command\n", HOSTNO);
2675                 /*
2676                  * We should perform BSY checking, and make sure we haven't slipped
2677                  * into BUS FREE.
2678                  */
2679
2680                 /*      NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN); */
2681                 /*
2682                  * Since we can't change phases until we've completed the current
2683                  * handshake, we have to source or sink a byte of data if the current
2684                  * phase is not MSGOUT.
2685                  */
2686
2687                 /*
2688                  * Return control to the executing NCR drive so we can clear the
2689                  * aborted flag and get back into our main loop.
2690                  */
2691
2692                 if (do_abort(instance) == 0) {
2693                         hostdata->aborted = 1;
2694                         hostdata->connected = NULL;
2695                         cmd->result = DID_ABORT << 16;
2696 #ifdef SUPPORT_TAGS
2697                         cmd_free_tag(cmd);
2698 #else
2699                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2700 #endif
2701                         local_irq_restore(flags);
2702                         cmd->scsi_done(cmd);
2703                         falcon_release_lock_if_possible(hostdata);
2704                         return SCSI_ABORT_SUCCESS;
2705                 } else {
2706 /*                      local_irq_restore(flags); */
2707                         printk("scsi%d: abort of connected command failed!\n", HOSTNO);
2708                         return SCSI_ABORT_ERROR;
2709                 }
2710         }
2711 #endif
2712
2713         /*
2714          * Case 2 : If the command hasn't been issued yet, we simply remove it
2715          *          from the issue queue.
2716          */
2717         for (prev = (Scsi_Cmnd **)&(hostdata->issue_queue),
2718              tmp = (Scsi_Cmnd *)hostdata->issue_queue;
2719              tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) {
2720                 if (cmd == tmp) {
2721                         REMOVE(5, *prev, tmp, NEXT(tmp));
2722                         (*prev) = NEXT(tmp);
2723                         SET_NEXT(tmp, NULL);
2724                         tmp->result = DID_ABORT << 16;
2725                         local_irq_restore(flags);
2726                         ABRT_PRINTK("scsi%d: abort removed command from issue queue.\n",
2727                                     HOSTNO);
2728                         /* Tagged queuing note: no tag to free here, hasn't been assigned
2729                          * yet... */
2730                         tmp->scsi_done(tmp);
2731                         falcon_release_lock_if_possible(hostdata);
2732                         return SCSI_ABORT_SUCCESS;
2733                 }
2734         }
2735
2736         /*
2737          * Case 3 : If any commands are connected, we're going to fail the abort
2738          *          and let the high level SCSI driver retry at a later time or
2739          *          issue a reset.
2740          *
2741          *          Timeouts, and therefore aborted commands, will be highly unlikely
2742          *          and handling them cleanly in this situation would make the common
2743          *          case of noresets less efficient, and would pollute our code.  So,
2744          *          we fail.
2745          */
2746
2747         if (hostdata->connected) {
2748                 local_irq_restore(flags);
2749                 ABRT_PRINTK("scsi%d: abort failed, command connected.\n", HOSTNO);
2750                 return SCSI_ABORT_SNOOZE;
2751         }
2752
2753         /*
2754          * Case 4: If the command is currently disconnected from the bus, and
2755          *      there are no connected commands, we reconnect the I_T_L or
2756          *      I_T_L_Q nexus associated with it, go into message out, and send
2757          *      an abort message.
2758          *
2759          * This case is especially ugly. In order to reestablish the nexus, we
2760          * need to call NCR5380_select().  The easiest way to implement this
2761          * function was to abort if the bus was busy, and let the interrupt
2762          * handler triggered on the SEL for reselect take care of lost arbitrations
2763          * where necessary, meaning interrupts need to be enabled.
2764          *
2765          * When interrupts are enabled, the queues may change - so we
2766          * can't remove it from the disconnected queue before selecting it
2767          * because that could cause a failure in hashing the nexus if that
2768          * device reselected.
2769          *
2770          * Since the queues may change, we can't use the pointers from when we
2771          * first locate it.
2772          *
2773          * So, we must first locate the command, and if NCR5380_select()
2774          * succeeds, then issue the abort, relocate the command and remove
2775          * it from the disconnected queue.
2776          */
2777
2778         for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp;
2779              tmp = NEXT(tmp)) {
2780                 if (cmd == tmp) {
2781                         local_irq_restore(flags);
2782                         ABRT_PRINTK("scsi%d: aborting disconnected command.\n", HOSTNO);
2783
2784                         if (NCR5380_select(instance, cmd, (int)cmd->tag))
2785                                 return SCSI_ABORT_BUSY;
2786
2787                         ABRT_PRINTK("scsi%d: nexus reestablished.\n", HOSTNO);
2788
2789                         do_abort(instance);
2790
2791                         local_irq_save(flags);
2792                         for (prev = (Scsi_Cmnd **)&(hostdata->disconnected_queue),
2793                              tmp = (Scsi_Cmnd *)hostdata->disconnected_queue;
2794                              tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) {
2795                                 if (cmd == tmp) {
2796                                         REMOVE(5, *prev, tmp, NEXT(tmp));
2797                                         *prev = NEXT(tmp);
2798                                         SET_NEXT(tmp, NULL);
2799                                         tmp->result = DID_ABORT << 16;
2800                                         /* We must unlock the tag/LUN immediately here, since the
2801                                          * target goes to BUS FREE and doesn't send us another
2802                                          * message (COMMAND_COMPLETE or the like)
2803                                          */
2804 #ifdef SUPPORT_TAGS
2805                                         cmd_free_tag(tmp);
2806 #else
2807                                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2808 #endif
2809                                         local_irq_restore(flags);
2810                                         tmp->scsi_done(tmp);
2811                                         falcon_release_lock_if_possible(hostdata);
2812                                         return SCSI_ABORT_SUCCESS;
2813                                 }
2814                         }
2815                 }
2816         }
2817
2818         /*
2819          * Case 5 : If we reached this point, the command was not found in any of
2820          *          the queues.
2821          *
2822          * We probably reached this point because of an unlikely race condition
2823          * between the command completing successfully and the abortion code,
2824          * so we won't panic, but we will notify the user in case something really
2825          * broke.
2826          */
2827
2828         local_irq_restore(flags);
2829         printk(KERN_INFO "scsi%d: warning : SCSI command probably completed successfully\n"
2830                KERN_INFO "        before abortion\n", HOSTNO);
2831
2832         /* Maybe it is sufficient just to release the ST-DMA lock... (if
2833          * possible at all) At least, we should check if the lock could be
2834          * released after the abort, in case it is kept due to some bug.
2835          */
2836         falcon_release_lock_if_possible(hostdata);
2837
2838         return SCSI_ABORT_NOT_RUNNING;
2839 }
2840
2841
2842 /*
2843  * Function : int NCR5380_reset (Scsi_Cmnd *cmd)
2844  *
2845  * Purpose : reset the SCSI bus.
2846  *
2847  * Returns : SCSI_RESET_WAKEUP
2848  *
2849  */
2850
2851 static int NCR5380_bus_reset(Scsi_Cmnd *cmd)
2852 {
2853         SETUP_HOSTDATA(cmd->device->host);
2854         int i;
2855         unsigned long flags;
2856 #if 1
2857         Scsi_Cmnd *connected, *disconnected_queue;
2858 #endif
2859
2860         if (!IS_A_TT() && !falcon_got_lock)
2861                 printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_reset\n",
2862                        H_NO(cmd));
2863
2864         NCR5380_print_status(cmd->device->host);
2865
2866         /* get in phase */
2867         NCR5380_write(TARGET_COMMAND_REG,
2868                       PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG)));
2869         /* assert RST */
2870         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST);
2871         udelay(40);
2872         /* reset NCR registers */
2873         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2874         NCR5380_write(MODE_REG, MR_BASE);
2875         NCR5380_write(TARGET_COMMAND_REG, 0);
2876         NCR5380_write(SELECT_ENABLE_REG, 0);
2877         /* ++roman: reset interrupt condition! otherwise no interrupts don't get
2878          * through anymore ... */
2879         (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
2880
2881 #if 1   /* XXX Should now be done by midlevel code, but it's broken XXX */
2882         /* XXX see below                                            XXX */
2883
2884         /* MSch: old-style reset: actually abort all command processing here */
2885
2886         /* After the reset, there are no more connected or disconnected commands
2887          * and no busy units; to avoid problems with re-inserting the commands
2888          * into the issue_queue (via scsi_done()), the aborted commands are
2889          * remembered in local variables first.
2890          */
2891         local_irq_save(flags);
2892         connected = (Scsi_Cmnd *)hostdata->connected;
2893         hostdata->connected = NULL;
2894         disconnected_queue = (Scsi_Cmnd *)hostdata->disconnected_queue;
2895         hostdata->disconnected_queue = NULL;
2896 #ifdef SUPPORT_TAGS
2897         free_all_tags();
2898 #endif
2899         for (i = 0; i < 8; ++i)
2900                 hostdata->busy[i] = 0;
2901 #ifdef REAL_DMA
2902         hostdata->dma_len = 0;
2903 #endif
2904         local_irq_restore(flags);
2905
2906         /* In order to tell the mid-level code which commands were aborted,
2907          * set the command status to DID_RESET and call scsi_done() !!!
2908          * This ultimately aborts processing of these commands in the mid-level.
2909          */
2910
2911         if ((cmd = connected)) {
2912                 ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd));
2913                 cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
2914                 cmd->scsi_done(cmd);
2915         }
2916
2917         for (i = 0; (cmd = disconnected_queue); ++i) {
2918                 disconnected_queue = NEXT(cmd);
2919                 SET_NEXT(cmd, NULL);
2920                 cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
2921                 cmd->scsi_done(cmd);
2922         }
2923         if (i > 0)
2924                 ABRT_PRINTK("scsi: reset aborted %d disconnected command(s)\n", i);
2925
2926         /* The Falcon lock should be released after a reset...
2927          */
2928         /* ++guenther: moved to atari_scsi_reset(), to prevent a race between
2929          * unlocking and enabling dma interrupt.
2930          */
2931 /*      falcon_release_lock_if_possible( hostdata );*/
2932
2933         /* since all commands have been explicitly terminated, we need to tell
2934          * the midlevel code that the reset was SUCCESSFUL, and there is no
2935          * need to 'wake up' the commands by a request_sense
2936          */
2937         return SCSI_RESET_SUCCESS | SCSI_RESET_BUS_RESET;
2938 #else /* 1 */
2939
2940         /* MSch: new-style reset handling: let the mid-level do what it can */
2941
2942         /* ++guenther: MID-LEVEL IS STILL BROKEN.
2943          * Mid-level is supposed to requeue all commands that were active on the
2944          * various low-level queues. In fact it does this, but that's not enough
2945          * because all these commands are subject to timeout. And if a timeout
2946          * happens for any removed command, *_abort() is called but all queues
2947          * are now empty. Abort then gives up the falcon lock, which is fatal,
2948          * since the mid-level will queue more commands and must have the lock
2949          * (it's all happening inside timer interrupt handler!!).
2950          * Even worse, abort will return NOT_RUNNING for all those commands not
2951          * on any queue, so they won't be retried ...
2952          *
2953          * Conclusion: either scsi.c disables timeout for all resetted commands
2954          * immediately, or we lose!  As of linux-2.0.20 it doesn't.
2955          */
2956
2957         /* After the reset, there are no more connected or disconnected commands
2958          * and no busy units; so clear the low-level status here to avoid
2959          * conflicts when the mid-level code tries to wake up the affected
2960          * commands!
2961          */
2962
2963         if (hostdata->issue_queue)
2964                 ABRT_PRINTK("scsi%d: reset aborted issued command(s)\n", H_NO(cmd));
2965         if (hostdata->connected)
2966                 ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd));
2967         if (hostdata->disconnected_queue)
2968                 ABRT_PRINTK("scsi%d: reset aborted disconnected command(s)\n", H_NO(cmd));
2969
2970         local_irq_save(flags);
2971         hostdata->issue_queue = NULL;
2972         hostdata->connected = NULL;
2973         hostdata->disconnected_queue = NULL;
2974 #ifdef SUPPORT_TAGS
2975         free_all_tags();
2976 #endif
2977         for (i = 0; i < 8; ++i)
2978                 hostdata->busy[i] = 0;
2979 #ifdef REAL_DMA
2980         hostdata->dma_len = 0;
2981 #endif
2982         local_irq_restore(flags);
2983
2984         /* we did no complete reset of all commands, so a wakeup is required */
2985         return SCSI_RESET_WAKEUP | SCSI_RESET_BUS_RESET;
2986 #endif /* 1 */
2987 }