[SCSI] megaraid_sas: Fix FastPath I/O to work on degraded raid 1
[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 transferred 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/gfp.h>
655 #include <linux/workqueue.h>
656 #include <linux/interrupt.h>
657
658 static volatile int main_running;
659 static DECLARE_WORK(NCR5380_tqueue, NCR5380_main);
660
661 static inline void queue_main(void)
662 {
663         if (!main_running) {
664                 /* If in interrupt and NCR5380_main() not already running,
665                    queue it on the 'immediate' task queue, to be processed
666                    immediately after the current interrupt processing has
667                    finished. */
668                 schedule_work(&NCR5380_tqueue);
669         }
670         /* else: nothing to do: the running NCR5380_main() will pick up
671            any newly queued command. */
672 }
673
674
675 static inline void NCR5380_all_init(void)
676 {
677         static int done = 0;
678         if (!done) {
679                 INI_PRINTK("scsi : NCR5380_all_init()\n");
680                 done = 1;
681         }
682 }
683
684
685 /*
686  * Function : void NCR58380_print_options (struct Scsi_Host *instance)
687  *
688  * Purpose : called by probe code indicating the NCR5380 driver
689  *           options that were selected.
690  *
691  * Inputs : instance, pointer to this instance.  Unused.
692  */
693
694 static void __init NCR5380_print_options(struct Scsi_Host *instance)
695 {
696         printk(" generic options"
697 #ifdef AUTOSENSE
698                " AUTOSENSE"
699 #endif
700 #ifdef REAL_DMA
701                " REAL DMA"
702 #endif
703 #ifdef PARITY
704                " PARITY"
705 #endif
706 #ifdef SUPPORT_TAGS
707                " SCSI-2 TAGGED QUEUING"
708 #endif
709                );
710         printk(" generic release=%d", NCR5380_PUBLIC_RELEASE);
711 }
712
713 /*
714  * Function : void NCR5380_print_status (struct Scsi_Host *instance)
715  *
716  * Purpose : print commands in the various queues, called from
717  *      NCR5380_abort and NCR5380_debug to aid debugging.
718  *
719  * Inputs : instance, pointer to this instance.
720  */
721
722 static void NCR5380_print_status(struct Scsi_Host *instance)
723 {
724         char *pr_bfr;
725         char *start;
726         int len;
727
728         NCR_PRINT(NDEBUG_ANY);
729         NCR_PRINT_PHASE(NDEBUG_ANY);
730
731         pr_bfr = (char *)__get_free_page(GFP_ATOMIC);
732         if (!pr_bfr) {
733                 printk("NCR5380_print_status: no memory for print buffer\n");
734                 return;
735         }
736         len = NCR5380_proc_info(instance, pr_bfr, &start, 0, PAGE_SIZE, 0);
737         pr_bfr[len] = 0;
738         printk("\n%s\n", pr_bfr);
739         free_page((unsigned long)pr_bfr);
740 }
741
742
743 /******************************************/
744 /*
745  * /proc/scsi/[dtc pas16 t128 generic]/[0-ASC_NUM_BOARD_SUPPORTED]
746  *
747  * *buffer: I/O buffer
748  * **start: if inout == FALSE pointer into buffer where user read should start
749  * offset: current offset
750  * length: length of buffer
751  * hostno: Scsi_Host host_no
752  * inout: TRUE - user is writing; FALSE - user is reading
753  *
754  * Return the number of bytes read from or written
755 */
756
757 #undef SPRINTF
758 #define SPRINTF(fmt,args...)                                                    \
759         do {                                                                    \
760                 if (pos + strlen(fmt) + 20 /* slop */ < buffer + length)        \
761                         pos += sprintf(pos, fmt , ## args);                     \
762         } while(0)
763 static char *lprint_Scsi_Cmnd(Scsi_Cmnd *cmd, char *pos, char *buffer, int length);
764
765 static int NCR5380_proc_info(struct Scsi_Host *instance, char *buffer,
766                              char **start, off_t offset, int length, int inout)
767 {
768         char *pos = buffer;
769         struct NCR5380_hostdata *hostdata;
770         Scsi_Cmnd *ptr;
771         unsigned long flags;
772         off_t begin = 0;
773 #define check_offset()                                  \
774         do {                                            \
775                 if (pos - buffer < offset - begin) {    \
776                         begin += pos - buffer;          \
777                         pos = buffer;                   \
778                 }                                       \
779         } while (0)
780
781         hostdata = (struct NCR5380_hostdata *)instance->hostdata;
782
783         if (inout)                      /* Has data been written to the file ? */
784                 return -ENOSYS;         /* Currently this is a no-op */
785         SPRINTF("NCR5380 core release=%d.\n", NCR5380_PUBLIC_RELEASE);
786         check_offset();
787         local_irq_save(flags);
788         SPRINTF("NCR5380: coroutine is%s running.\n",
789                 main_running ? "" : "n't");
790         check_offset();
791         if (!hostdata->connected)
792                 SPRINTF("scsi%d: no currently connected command\n", HOSTNO);
793         else
794                 pos = lprint_Scsi_Cmnd((Scsi_Cmnd *) hostdata->connected,
795                                        pos, buffer, length);
796         SPRINTF("scsi%d: issue_queue\n", HOSTNO);
797         check_offset();
798         for (ptr = (Scsi_Cmnd *)hostdata->issue_queue; ptr; ptr = NEXT(ptr)) {
799                 pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length);
800                 check_offset();
801         }
802
803         SPRINTF("scsi%d: disconnected_queue\n", HOSTNO);
804         check_offset();
805         for (ptr = (Scsi_Cmnd *) hostdata->disconnected_queue; ptr;
806              ptr = NEXT(ptr)) {
807                 pos = lprint_Scsi_Cmnd(ptr, pos, buffer, length);
808                 check_offset();
809         }
810
811         local_irq_restore(flags);
812         *start = buffer + (offset - begin);
813         if (pos - buffer < offset - begin)
814                 return 0;
815         else if (pos - buffer - (offset - begin) < length)
816                 return pos - buffer - (offset - begin);
817         return length;
818 }
819
820 static char *lprint_Scsi_Cmnd(Scsi_Cmnd *cmd, char *pos, char *buffer, int length)
821 {
822         int i, s;
823         unsigned char *command;
824         SPRINTF("scsi%d: destination target %d, lun %d\n",
825                 H_NO(cmd), cmd->device->id, cmd->device->lun);
826         SPRINTF("        command = ");
827         command = cmd->cmnd;
828         SPRINTF("%2d (0x%02x)", command[0], command[0]);
829         for (i = 1, s = COMMAND_SIZE(command[0]); i < s; ++i)
830                 SPRINTF(" %02x", command[i]);
831         SPRINTF("\n");
832         return pos;
833 }
834
835
836 /*
837  * Function : void NCR5380_init (struct Scsi_Host *instance)
838  *
839  * Purpose : initializes *instance and corresponding 5380 chip.
840  *
841  * Inputs : instance - instantiation of the 5380 driver.
842  *
843  * Notes : I assume that the host, hostno, and id bits have been
844  *      set correctly.  I don't care about the irq and other fields.
845  *
846  */
847
848 static int __init NCR5380_init(struct Scsi_Host *instance, int flags)
849 {
850         int i;
851         SETUP_HOSTDATA(instance);
852
853         NCR5380_all_init();
854
855         hostdata->aborted = 0;
856         hostdata->id_mask = 1 << instance->this_id;
857         hostdata->id_higher_mask = 0;
858         for (i = hostdata->id_mask; i <= 0x80; i <<= 1)
859                 if (i > hostdata->id_mask)
860                         hostdata->id_higher_mask |= i;
861         for (i = 0; i < 8; ++i)
862                 hostdata->busy[i] = 0;
863 #ifdef SUPPORT_TAGS
864         init_tags();
865 #endif
866 #if defined (REAL_DMA)
867         hostdata->dma_len = 0;
868 #endif
869         hostdata->targets_present = 0;
870         hostdata->connected = NULL;
871         hostdata->issue_queue = NULL;
872         hostdata->disconnected_queue = NULL;
873         hostdata->flags = FLAG_CHECK_LAST_BYTE_SENT;
874
875         if (!the_template) {
876                 the_template = instance->hostt;
877                 first_instance = instance;
878         }
879
880 #ifndef AUTOSENSE
881         if ((instance->cmd_per_lun > 1) || (instance->can_queue > 1))
882                 printk("scsi%d: WARNING : support for multiple outstanding commands enabled\n"
883                        "        without AUTOSENSE option, contingent allegiance conditions may\n"
884                        "        be incorrectly cleared.\n", HOSTNO);
885 #endif /* def AUTOSENSE */
886
887         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
888         NCR5380_write(MODE_REG, MR_BASE);
889         NCR5380_write(TARGET_COMMAND_REG, 0);
890         NCR5380_write(SELECT_ENABLE_REG, 0);
891
892         return 0;
893 }
894
895 static void NCR5380_exit(struct Scsi_Host *instance)
896 {
897         /* Empty, as we didn't schedule any delayed work */
898 }
899
900 /*
901  * Function : int NCR5380_queue_command (Scsi_Cmnd *cmd,
902  *      void (*done)(Scsi_Cmnd *))
903  *
904  * Purpose :  enqueues a SCSI command
905  *
906  * Inputs : cmd - SCSI command, done - function called on completion, with
907  *      a pointer to the command descriptor.
908  *
909  * Returns : 0
910  *
911  * Side effects :
912  *      cmd is added to the per instance issue_queue, with minor
913  *      twiddling done to the host specific fields of cmd.  If the
914  *      main coroutine is not running, it is restarted.
915  *
916  */
917
918 static int NCR5380_queue_command_lck(Scsi_Cmnd *cmd, void (*done)(Scsi_Cmnd *))
919 {
920         SETUP_HOSTDATA(cmd->device->host);
921         Scsi_Cmnd *tmp;
922         unsigned long flags;
923
924 #if (NDEBUG & NDEBUG_NO_WRITE)
925         switch (cmd->cmnd[0]) {
926         case WRITE_6:
927         case WRITE_10:
928                 printk(KERN_NOTICE "scsi%d: WRITE attempted with NO_WRITE debugging flag set\n",
929                        H_NO(cmd));
930                 cmd->result = (DID_ERROR << 16);
931                 done(cmd);
932                 return 0;
933         }
934 #endif /* (NDEBUG & NDEBUG_NO_WRITE) */
935
936 #ifdef NCR5380_STATS
937 # if 0
938         if (!hostdata->connected && !hostdata->issue_queue &&
939             !hostdata->disconnected_queue) {
940                 hostdata->timebase = jiffies;
941         }
942 # endif
943 # ifdef NCR5380_STAT_LIMIT
944         if (scsi_bufflen(cmd) > NCR5380_STAT_LIMIT)
945 # endif
946                 switch (cmd->cmnd[0]) {
947                 case WRITE:
948                 case WRITE_6:
949                 case WRITE_10:
950                         hostdata->time_write[cmd->device->id] -= (jiffies - hostdata->timebase);
951                         hostdata->bytes_write[cmd->device->id] += scsi_bufflen(cmd);
952                         hostdata->pendingw++;
953                         break;
954                 case READ:
955                 case READ_6:
956                 case READ_10:
957                         hostdata->time_read[cmd->device->id] -= (jiffies - hostdata->timebase);
958                         hostdata->bytes_read[cmd->device->id] += scsi_bufflen(cmd);
959                         hostdata->pendingr++;
960                         break;
961                 }
962 #endif
963
964         /*
965          * We use the host_scribble field as a pointer to the next command
966          * in a queue
967          */
968
969         SET_NEXT(cmd, NULL);
970         cmd->scsi_done = done;
971
972         cmd->result = 0;
973
974         /*
975          * Insert the cmd into the issue queue. Note that REQUEST SENSE
976          * commands are added to the head of the queue since any command will
977          * clear the contingent allegiance condition that exists and the
978          * sense data is only guaranteed to be valid while the condition exists.
979          */
980
981         local_irq_save(flags);
982         /* ++guenther: now that the issue queue is being set up, we can lock ST-DMA.
983          * Otherwise a running NCR5380_main may steal the lock.
984          * Lock before actually inserting due to fairness reasons explained in
985          * atari_scsi.c. If we insert first, then it's impossible for this driver
986          * to release the lock.
987          * Stop timer for this command while waiting for the lock, or timeouts
988          * may happen (and they really do), and it's no good if the command doesn't
989          * appear in any of the queues.
990          * ++roman: Just disabling the NCR interrupt isn't sufficient here,
991          * because also a timer int can trigger an abort or reset, which would
992          * alter queues and touch the lock.
993          */
994         if (!IS_A_TT()) {
995                 /* perhaps stop command timer here */
996                 falcon_get_lock();
997                 /* perhaps restart command timer here */
998         }
999         if (!(hostdata->issue_queue) || (cmd->cmnd[0] == REQUEST_SENSE)) {
1000                 LIST(cmd, hostdata->issue_queue);
1001                 SET_NEXT(cmd, hostdata->issue_queue);
1002                 hostdata->issue_queue = cmd;
1003         } else {
1004                 for (tmp = (Scsi_Cmnd *)hostdata->issue_queue;
1005                      NEXT(tmp); tmp = NEXT(tmp))
1006                         ;
1007                 LIST(cmd, tmp);
1008                 SET_NEXT(tmp, cmd);
1009         }
1010         local_irq_restore(flags);
1011
1012         QU_PRINTK("scsi%d: command added to %s of queue\n", H_NO(cmd),
1013                   (cmd->cmnd[0] == REQUEST_SENSE) ? "head" : "tail");
1014
1015         /* If queue_command() is called from an interrupt (real one or bottom
1016          * half), we let queue_main() do the job of taking care about main. If it
1017          * is already running, this is a no-op, else main will be queued.
1018          *
1019          * If we're not in an interrupt, we can call NCR5380_main()
1020          * unconditionally, because it cannot be already running.
1021          */
1022         if (in_interrupt() || ((flags >> 8) & 7) >= 6)
1023                 queue_main();
1024         else
1025                 NCR5380_main(NULL);
1026         return 0;
1027 }
1028
1029 static DEF_SCSI_QCMD(NCR5380_queue_command)
1030
1031 /*
1032  * Function : NCR5380_main (void)
1033  *
1034  * Purpose : NCR5380_main is a coroutine that runs as long as more work can
1035  *      be done on the NCR5380 host adapters in a system.  Both
1036  *      NCR5380_queue_command() and NCR5380_intr() will try to start it
1037  *      in case it is not running.
1038  *
1039  * NOTE : NCR5380_main exits with interrupts *disabled*, the caller should
1040  *  reenable them.  This prevents reentrancy and kernel stack overflow.
1041  */
1042
1043 static void NCR5380_main(struct work_struct *work)
1044 {
1045         Scsi_Cmnd *tmp, *prev;
1046         struct Scsi_Host *instance = first_instance;
1047         struct NCR5380_hostdata *hostdata = HOSTDATA(instance);
1048         int done;
1049         unsigned long flags;
1050
1051         /*
1052          * We run (with interrupts disabled) until we're sure that none of
1053          * the host adapters have anything that can be done, at which point
1054          * we set main_running to 0 and exit.
1055          *
1056          * Interrupts are enabled before doing various other internal
1057          * instructions, after we've decided that we need to run through
1058          * the loop again.
1059          *
1060          * this should prevent any race conditions.
1061          *
1062          * ++roman: Just disabling the NCR interrupt isn't sufficient here,
1063          * because also a timer int can trigger an abort or reset, which can
1064          * alter queues and touch the Falcon lock.
1065          */
1066
1067         /* Tell int handlers main() is now already executing.  Note that
1068            no races are possible here. If an int comes in before
1069            'main_running' is set here, and queues/executes main via the
1070            task queue, it doesn't do any harm, just this instance of main
1071            won't find any work left to do. */
1072         if (main_running)
1073                 return;
1074         main_running = 1;
1075
1076         local_save_flags(flags);
1077         do {
1078                 local_irq_disable();    /* Freeze request queues */
1079                 done = 1;
1080
1081                 if (!hostdata->connected) {
1082                         MAIN_PRINTK("scsi%d: not connected\n", HOSTNO);
1083                         /*
1084                          * Search through the issue_queue for a command destined
1085                          * for a target that's not busy.
1086                          */
1087 #if (NDEBUG & NDEBUG_LISTS)
1088                         for (tmp = (Scsi_Cmnd *) hostdata->issue_queue, prev = NULL;
1089                              tmp && (tmp != prev); prev = tmp, tmp = NEXT(tmp))
1090                                 ;
1091                         /*printk("%p  ", tmp);*/
1092                         if ((tmp == prev) && tmp)
1093                                 printk(" LOOP\n");
1094                         /* else printk("\n"); */
1095 #endif
1096                         for (tmp = (Scsi_Cmnd *) hostdata->issue_queue,
1097                              prev = NULL; tmp; prev = tmp, tmp = NEXT(tmp)) {
1098
1099 #if (NDEBUG & NDEBUG_LISTS)
1100                                 if (prev != tmp)
1101                                         printk("MAIN tmp=%p   target=%d   busy=%d lun=%d\n",
1102                                                tmp, tmp->device->id, hostdata->busy[tmp->device->id],
1103                                                tmp->device->lun);
1104 #endif
1105                                 /*  When we find one, remove it from the issue queue. */
1106                                 /* ++guenther: possible race with Falcon locking */
1107                                 if (
1108 #ifdef SUPPORT_TAGS
1109                                     !is_lun_busy( tmp, tmp->cmnd[0] != REQUEST_SENSE)
1110 #else
1111                                     !(hostdata->busy[tmp->device->id] & (1 << tmp->device->lun))
1112 #endif
1113                                     ) {
1114                                         /* ++guenther: just to be sure, this must be atomic */
1115                                         local_irq_disable();
1116                                         if (prev) {
1117                                                 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
1118                                                 SET_NEXT(prev, NEXT(tmp));
1119                                         } else {
1120                                                 REMOVE(-1, hostdata->issue_queue, tmp, NEXT(tmp));
1121                                                 hostdata->issue_queue = NEXT(tmp);
1122                                         }
1123                                         SET_NEXT(tmp, NULL);
1124                                         falcon_dont_release++;
1125
1126                                         /* reenable interrupts after finding one */
1127                                         local_irq_restore(flags);
1128
1129                                         /*
1130                                          * Attempt to establish an I_T_L nexus here.
1131                                          * On success, instance->hostdata->connected is set.
1132                                          * On failure, we must add the command back to the
1133                                          *   issue queue so we can keep trying.
1134                                          */
1135                                         MAIN_PRINTK("scsi%d: main(): command for target %d "
1136                                                     "lun %d removed from issue_queue\n",
1137                                                     HOSTNO, tmp->device->id, tmp->device->lun);
1138                                         /*
1139                                          * REQUEST SENSE commands are issued without tagged
1140                                          * queueing, even on SCSI-II devices because the
1141                                          * contingent allegiance condition exists for the
1142                                          * entire unit.
1143                                          */
1144                                         /* ++roman: ...and the standard also requires that
1145                                          * REQUEST SENSE command are untagged.
1146                                          */
1147
1148 #ifdef SUPPORT_TAGS
1149                                         cmd_get_tag(tmp, tmp->cmnd[0] != REQUEST_SENSE);
1150 #endif
1151                                         if (!NCR5380_select(instance, tmp,
1152                                             (tmp->cmnd[0] == REQUEST_SENSE) ? TAG_NONE :
1153                                             TAG_NEXT)) {
1154                                                 falcon_dont_release--;
1155                                                 /* release if target did not response! */
1156                                                 falcon_release_lock_if_possible(hostdata);
1157                                                 break;
1158                                         } else {
1159                                                 local_irq_disable();
1160                                                 LIST(tmp, hostdata->issue_queue);
1161                                                 SET_NEXT(tmp, hostdata->issue_queue);
1162                                                 hostdata->issue_queue = tmp;
1163 #ifdef SUPPORT_TAGS
1164                                                 cmd_free_tag(tmp);
1165 #endif
1166                                                 falcon_dont_release--;
1167                                                 local_irq_restore(flags);
1168                                                 MAIN_PRINTK("scsi%d: main(): select() failed, "
1169                                                             "returned to issue_queue\n", HOSTNO);
1170                                                 if (hostdata->connected)
1171                                                         break;
1172                                         }
1173                                 } /* if target/lun/target queue is not busy */
1174                         } /* for issue_queue */
1175                 } /* if (!hostdata->connected) */
1176
1177                 if (hostdata->connected
1178 #ifdef REAL_DMA
1179                     && !hostdata->dma_len
1180 #endif
1181                     ) {
1182                         local_irq_restore(flags);
1183                         MAIN_PRINTK("scsi%d: main: performing information transfer\n",
1184                                     HOSTNO);
1185                         NCR5380_information_transfer(instance);
1186                         MAIN_PRINTK("scsi%d: main: done set false\n", HOSTNO);
1187                         done = 0;
1188                 }
1189         } while (!done);
1190
1191         /* Better allow ints _after_ 'main_running' has been cleared, else
1192            an interrupt could believe we'll pick up the work it left for
1193            us, but we won't see it anymore here... */
1194         main_running = 0;
1195         local_irq_restore(flags);
1196 }
1197
1198
1199 #ifdef REAL_DMA
1200 /*
1201  * Function : void NCR5380_dma_complete (struct Scsi_Host *instance)
1202  *
1203  * Purpose : Called by interrupt handler when DMA finishes or a phase
1204  *      mismatch occurs (which would finish the DMA transfer).
1205  *
1206  * Inputs : instance - this instance of the NCR5380.
1207  *
1208  */
1209
1210 static void NCR5380_dma_complete(struct Scsi_Host *instance)
1211 {
1212         SETUP_HOSTDATA(instance);
1213         int transfered, saved_data = 0, overrun = 0, cnt, toPIO;
1214         unsigned char **data, p;
1215         volatile int *count;
1216
1217         if (!hostdata->connected) {
1218                 printk(KERN_WARNING "scsi%d: received end of DMA interrupt with "
1219                        "no connected cmd\n", HOSTNO);
1220                 return;
1221         }
1222
1223         if (atari_read_overruns) {
1224                 p = hostdata->connected->SCp.phase;
1225                 if (p & SR_IO) {
1226                         udelay(10);
1227                         if ((NCR5380_read(BUS_AND_STATUS_REG) &
1228                              (BASR_PHASE_MATCH|BASR_ACK)) ==
1229                             (BASR_PHASE_MATCH|BASR_ACK)) {
1230                                 saved_data = NCR5380_read(INPUT_DATA_REG);
1231                                 overrun = 1;
1232                                 DMA_PRINTK("scsi%d: read overrun handled\n", HOSTNO);
1233                         }
1234                 }
1235         }
1236
1237         DMA_PRINTK("scsi%d: real DMA transfer complete, basr 0x%X, sr 0x%X\n",
1238                    HOSTNO, NCR5380_read(BUS_AND_STATUS_REG),
1239                    NCR5380_read(STATUS_REG));
1240
1241         (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1242         NCR5380_write(MODE_REG, MR_BASE);
1243         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1244
1245         transfered = hostdata->dma_len - NCR5380_dma_residual(instance);
1246         hostdata->dma_len = 0;
1247
1248         data = (unsigned char **)&hostdata->connected->SCp.ptr;
1249         count = &hostdata->connected->SCp.this_residual;
1250         *data += transfered;
1251         *count -= transfered;
1252
1253         if (atari_read_overruns) {
1254                 if ((NCR5380_read(STATUS_REG) & PHASE_MASK) == p && (p & SR_IO)) {
1255                         cnt = toPIO = atari_read_overruns;
1256                         if (overrun) {
1257                                 DMA_PRINTK("Got an input overrun, using saved byte\n");
1258                                 *(*data)++ = saved_data;
1259                                 (*count)--;
1260                                 cnt--;
1261                                 toPIO--;
1262                         }
1263                         DMA_PRINTK("Doing %d-byte PIO to 0x%08lx\n", cnt, (long)*data);
1264                         NCR5380_transfer_pio(instance, &p, &cnt, data);
1265                         *count -= toPIO - cnt;
1266                 }
1267         }
1268 }
1269 #endif /* REAL_DMA */
1270
1271
1272 /*
1273  * Function : void NCR5380_intr (int irq)
1274  *
1275  * Purpose : handle interrupts, reestablishing I_T_L or I_T_L_Q nexuses
1276  *      from the disconnected queue, and restarting NCR5380_main()
1277  *      as required.
1278  *
1279  * Inputs : int irq, irq that caused this interrupt.
1280  *
1281  */
1282
1283 static irqreturn_t NCR5380_intr(int irq, void *dev_id)
1284 {
1285         struct Scsi_Host *instance = first_instance;
1286         int done = 1, handled = 0;
1287         unsigned char basr;
1288
1289         INT_PRINTK("scsi%d: NCR5380 irq triggered\n", HOSTNO);
1290
1291         /* Look for pending interrupts */
1292         basr = NCR5380_read(BUS_AND_STATUS_REG);
1293         INT_PRINTK("scsi%d: BASR=%02x\n", HOSTNO, basr);
1294         /* dispatch to appropriate routine if found and done=0 */
1295         if (basr & BASR_IRQ) {
1296                 NCR_PRINT(NDEBUG_INTR);
1297                 if ((NCR5380_read(STATUS_REG) & (SR_SEL|SR_IO)) == (SR_SEL|SR_IO)) {
1298                         done = 0;
1299                         ENABLE_IRQ();
1300                         INT_PRINTK("scsi%d: SEL interrupt\n", HOSTNO);
1301                         NCR5380_reselect(instance);
1302                         (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1303                 } else if (basr & BASR_PARITY_ERROR) {
1304                         INT_PRINTK("scsi%d: PARITY interrupt\n", HOSTNO);
1305                         (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1306                 } else if ((NCR5380_read(STATUS_REG) & SR_RST) == SR_RST) {
1307                         INT_PRINTK("scsi%d: RESET interrupt\n", HOSTNO);
1308                         (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1309                 } else {
1310                         /*
1311                          * The rest of the interrupt conditions can occur only during a
1312                          * DMA transfer
1313                          */
1314
1315 #if defined(REAL_DMA)
1316                         /*
1317                          * We should only get PHASE MISMATCH and EOP interrupts if we have
1318                          * DMA enabled, so do a sanity check based on the current setting
1319                          * of the MODE register.
1320                          */
1321
1322                         if ((NCR5380_read(MODE_REG) & MR_DMA_MODE) &&
1323                             ((basr & BASR_END_DMA_TRANSFER) ||
1324                              !(basr & BASR_PHASE_MATCH))) {
1325
1326                                 INT_PRINTK("scsi%d: PHASE MISM or EOP interrupt\n", HOSTNO);
1327                                 NCR5380_dma_complete( instance );
1328                                 done = 0;
1329                                 ENABLE_IRQ();
1330                         } else
1331 #endif /* REAL_DMA */
1332                         {
1333 /* MS: Ignore unknown phase mismatch interrupts (caused by EOP interrupt) */
1334                                 if (basr & BASR_PHASE_MATCH)
1335                                         printk(KERN_NOTICE "scsi%d: unknown interrupt, "
1336                                                "BASR 0x%x, MR 0x%x, SR 0x%x\n",
1337                                                HOSTNO, basr, NCR5380_read(MODE_REG),
1338                                                NCR5380_read(STATUS_REG));
1339                                 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1340                         }
1341                 } /* if !(SELECTION || PARITY) */
1342                 handled = 1;
1343         } /* BASR & IRQ */ else {
1344                 printk(KERN_NOTICE "scsi%d: interrupt without IRQ bit set in BASR, "
1345                        "BASR 0x%X, MR 0x%X, SR 0x%x\n", HOSTNO, basr,
1346                        NCR5380_read(MODE_REG), NCR5380_read(STATUS_REG));
1347                 (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
1348         }
1349
1350         if (!done) {
1351                 INT_PRINTK("scsi%d: in int routine, calling main\n", HOSTNO);
1352                 /* Put a call to NCR5380_main() on the queue... */
1353                 queue_main();
1354         }
1355         return IRQ_RETVAL(handled);
1356 }
1357
1358 #ifdef NCR5380_STATS
1359 static void collect_stats(struct NCR5380_hostdata* hostdata, Scsi_Cmnd *cmd)
1360 {
1361 # ifdef NCR5380_STAT_LIMIT
1362         if (scsi_bufflen(cmd) > NCR5380_STAT_LIMIT)
1363 # endif
1364                 switch (cmd->cmnd[0]) {
1365                 case WRITE:
1366                 case WRITE_6:
1367                 case WRITE_10:
1368                         hostdata->time_write[cmd->device->id] += (jiffies - hostdata->timebase);
1369                         /*hostdata->bytes_write[cmd->device->id] += scsi_bufflen(cmd);*/
1370                         hostdata->pendingw--;
1371                         break;
1372                 case READ:
1373                 case READ_6:
1374                 case READ_10:
1375                         hostdata->time_read[cmd->device->id] += (jiffies - hostdata->timebase);
1376                         /*hostdata->bytes_read[cmd->device->id] += scsi_bufflen(cmd);*/
1377                         hostdata->pendingr--;
1378                         break;
1379                 }
1380 }
1381 #endif
1382
1383 /*
1384  * Function : int NCR5380_select (struct Scsi_Host *instance, Scsi_Cmnd *cmd,
1385  *      int tag);
1386  *
1387  * Purpose : establishes I_T_L or I_T_L_Q nexus for new or existing command,
1388  *      including ARBITRATION, SELECTION, and initial message out for
1389  *      IDENTIFY and queue messages.
1390  *
1391  * Inputs : instance - instantiation of the 5380 driver on which this
1392  *      target lives, cmd - SCSI command to execute, tag - set to TAG_NEXT for
1393  *      new tag, TAG_NONE for untagged queueing, otherwise set to the tag for
1394  *      the command that is presently connected.
1395  *
1396  * Returns : -1 if selection could not execute for some reason,
1397  *      0 if selection succeeded or failed because the target
1398  *      did not respond.
1399  *
1400  * Side effects :
1401  *      If bus busy, arbitration failed, etc, NCR5380_select() will exit
1402  *              with registers as they should have been on entry - ie
1403  *              SELECT_ENABLE will be set appropriately, the NCR5380
1404  *              will cease to drive any SCSI bus signals.
1405  *
1406  *      If successful : I_T_L or I_T_L_Q nexus will be established,
1407  *              instance->connected will be set to cmd.
1408  *              SELECT interrupt will be disabled.
1409  *
1410  *      If failed (no target) : cmd->scsi_done() will be called, and the
1411  *              cmd->result host byte set to DID_BAD_TARGET.
1412  */
1413
1414 static int NCR5380_select(struct Scsi_Host *instance, Scsi_Cmnd *cmd, int tag)
1415 {
1416         SETUP_HOSTDATA(instance);
1417         unsigned char tmp[3], phase;
1418         unsigned char *data;
1419         int len;
1420         unsigned long timeout;
1421         unsigned long flags;
1422
1423         hostdata->restart_select = 0;
1424         NCR_PRINT(NDEBUG_ARBITRATION);
1425         ARB_PRINTK("scsi%d: starting arbitration, id = %d\n", HOSTNO,
1426                    instance->this_id);
1427
1428         /*
1429          * Set the phase bits to 0, otherwise the NCR5380 won't drive the
1430          * data bus during SELECTION.
1431          */
1432
1433         local_irq_save(flags);
1434         if (hostdata->connected) {
1435                 local_irq_restore(flags);
1436                 return -1;
1437         }
1438         NCR5380_write(TARGET_COMMAND_REG, 0);
1439
1440         /*
1441          * Start arbitration.
1442          */
1443
1444         NCR5380_write(OUTPUT_DATA_REG, hostdata->id_mask);
1445         NCR5380_write(MODE_REG, MR_ARBITRATE);
1446
1447         local_irq_restore(flags);
1448
1449         /* Wait for arbitration logic to complete */
1450 #if defined(NCR_TIMEOUT)
1451         {
1452                 unsigned long timeout = jiffies + 2*NCR_TIMEOUT;
1453
1454                 while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) &&
1455                        time_before(jiffies, timeout) && !hostdata->connected)
1456                         ;
1457                 if (time_after_eq(jiffies, timeout)) {
1458                         printk("scsi : arbitration timeout at %d\n", __LINE__);
1459                         NCR5380_write(MODE_REG, MR_BASE);
1460                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1461                         return -1;
1462                 }
1463         }
1464 #else /* NCR_TIMEOUT */
1465         while (!(NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_PROGRESS) &&
1466                !hostdata->connected)
1467                 ;
1468 #endif
1469
1470         ARB_PRINTK("scsi%d: arbitration complete\n", HOSTNO);
1471
1472         if (hostdata->connected) {
1473                 NCR5380_write(MODE_REG, MR_BASE);
1474                 return -1;
1475         }
1476         /*
1477          * The arbitration delay is 2.2us, but this is a minimum and there is
1478          * no maximum so we can safely sleep for ceil(2.2) usecs to accommodate
1479          * the integral nature of udelay().
1480          *
1481          */
1482
1483         udelay(3);
1484
1485         /* Check for lost arbitration */
1486         if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1487             (NCR5380_read(CURRENT_SCSI_DATA_REG) & hostdata->id_higher_mask) ||
1488             (NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1489             hostdata->connected) {
1490                 NCR5380_write(MODE_REG, MR_BASE);
1491                 ARB_PRINTK("scsi%d: lost arbitration, deasserting MR_ARBITRATE\n",
1492                            HOSTNO);
1493                 return -1;
1494         }
1495
1496         /* after/during arbitration, BSY should be asserted.
1497            IBM DPES-31080 Version S31Q works now */
1498         /* Tnx to Thomas_Roesch@m2.maus.de for finding this! (Roman) */
1499         NCR5380_write(INITIATOR_COMMAND_REG,
1500                       ICR_BASE | ICR_ASSERT_SEL | ICR_ASSERT_BSY);
1501
1502         if ((NCR5380_read(INITIATOR_COMMAND_REG) & ICR_ARBITRATION_LOST) ||
1503             hostdata->connected) {
1504                 NCR5380_write(MODE_REG, MR_BASE);
1505                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1506                 ARB_PRINTK("scsi%d: lost arbitration, deasserting ICR_ASSERT_SEL\n",
1507                            HOSTNO);
1508                 return -1;
1509         }
1510
1511         /*
1512          * Again, bus clear + bus settle time is 1.2us, however, this is
1513          * a minimum so we'll udelay ceil(1.2)
1514          */
1515
1516 #ifdef CONFIG_ATARI_SCSI_TOSHIBA_DELAY
1517         /* ++roman: But some targets (see above :-) seem to need a bit more... */
1518         udelay(15);
1519 #else
1520         udelay(2);
1521 #endif
1522
1523         if (hostdata->connected) {
1524                 NCR5380_write(MODE_REG, MR_BASE);
1525                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1526                 return -1;
1527         }
1528
1529         ARB_PRINTK("scsi%d: won arbitration\n", HOSTNO);
1530
1531         /*
1532          * Now that we have won arbitration, start Selection process, asserting
1533          * the host and target ID's on the SCSI bus.
1534          */
1535
1536         NCR5380_write(OUTPUT_DATA_REG, (hostdata->id_mask | (1 << cmd->device->id)));
1537
1538         /*
1539          * Raise ATN while SEL is true before BSY goes false from arbitration,
1540          * since this is the only way to guarantee that we'll get a MESSAGE OUT
1541          * phase immediately after selection.
1542          */
1543
1544         NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_BSY |
1545                       ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_SEL ));
1546         NCR5380_write(MODE_REG, MR_BASE);
1547
1548         /*
1549          * Reselect interrupts must be turned off prior to the dropping of BSY,
1550          * otherwise we will trigger an interrupt.
1551          */
1552
1553         if (hostdata->connected) {
1554                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1555                 return -1;
1556         }
1557
1558         NCR5380_write(SELECT_ENABLE_REG, 0);
1559
1560         /*
1561          * The initiator shall then wait at least two deskew delays and release
1562          * the BSY signal.
1563          */
1564         udelay(1);        /* wingel -- wait two bus deskew delay >2*45ns */
1565
1566         /* Reset BSY */
1567         NCR5380_write(INITIATOR_COMMAND_REG, (ICR_BASE | ICR_ASSERT_DATA |
1568                       ICR_ASSERT_ATN | ICR_ASSERT_SEL));
1569
1570         /*
1571          * Something weird happens when we cease to drive BSY - looks
1572          * like the board/chip is letting us do another read before the
1573          * appropriate propagation delay has expired, and we're confusing
1574          * a BSY signal from ourselves as the target's response to SELECTION.
1575          *
1576          * A small delay (the 'C++' frontend breaks the pipeline with an
1577          * unnecessary jump, making it work on my 386-33/Trantor T128, the
1578          * tighter 'C' code breaks and requires this) solves the problem -
1579          * the 1 us delay is arbitrary, and only used because this delay will
1580          * be the same on other platforms and since it works here, it should
1581          * work there.
1582          *
1583          * wingel suggests that this could be due to failing to wait
1584          * one deskew delay.
1585          */
1586
1587         udelay(1);
1588
1589         SEL_PRINTK("scsi%d: selecting target %d\n", HOSTNO, cmd->device->id);
1590
1591         /*
1592          * The SCSI specification calls for a 250 ms timeout for the actual
1593          * selection.
1594          */
1595
1596         timeout = jiffies + 25;
1597
1598         /*
1599          * XXX very interesting - we're seeing a bounce where the BSY we
1600          * asserted is being reflected / still asserted (propagation delay?)
1601          * and it's detecting as true.  Sigh.
1602          */
1603
1604 #if 0
1605         /* ++roman: If a target conformed to the SCSI standard, it wouldn't assert
1606          * IO while SEL is true. But again, there are some disks out the in the
1607          * world that do that nevertheless. (Somebody claimed that this announces
1608          * reselection capability of the target.) So we better skip that test and
1609          * only wait for BSY... (Famous german words: Der Kl├╝gere gibt nach :-)
1610          */
1611
1612         while (time_before(jiffies, timeout) &&
1613                !(NCR5380_read(STATUS_REG) & (SR_BSY | SR_IO)))
1614                 ;
1615
1616         if ((NCR5380_read(STATUS_REG) & (SR_SEL | SR_IO)) == (SR_SEL | SR_IO)) {
1617                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1618                 NCR5380_reselect(instance);
1619                 printk(KERN_ERR "scsi%d: reselection after won arbitration?\n",
1620                        HOSTNO);
1621                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1622                 return -1;
1623         }
1624 #else
1625         while (time_before(jiffies, timeout) && !(NCR5380_read(STATUS_REG) & SR_BSY))
1626                 ;
1627 #endif
1628
1629         /*
1630          * No less than two deskew delays after the initiator detects the
1631          * BSY signal is true, it shall release the SEL signal and may
1632          * change the DATA BUS.                                     -wingel
1633          */
1634
1635         udelay(1);
1636
1637         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1638
1639         if (!(NCR5380_read(STATUS_REG) & SR_BSY)) {
1640                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1641                 if (hostdata->targets_present & (1 << cmd->device->id)) {
1642                         printk(KERN_ERR "scsi%d: weirdness\n", HOSTNO);
1643                         if (hostdata->restart_select)
1644                                 printk(KERN_NOTICE "\trestart select\n");
1645                         NCR_PRINT(NDEBUG_ANY);
1646                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1647                         return -1;
1648                 }
1649                 cmd->result = DID_BAD_TARGET << 16;
1650 #ifdef NCR5380_STATS
1651                 collect_stats(hostdata, cmd);
1652 #endif
1653 #ifdef SUPPORT_TAGS
1654                 cmd_free_tag(cmd);
1655 #endif
1656                 cmd->scsi_done(cmd);
1657                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1658                 SEL_PRINTK("scsi%d: target did not respond within 250ms\n", HOSTNO);
1659                 NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
1660                 return 0;
1661         }
1662
1663         hostdata->targets_present |= (1 << cmd->device->id);
1664
1665         /*
1666          * Since we followed the SCSI spec, and raised ATN while SEL
1667          * was true but before BSY was false during selection, the information
1668          * transfer phase should be a MESSAGE OUT phase so that we can send the
1669          * IDENTIFY message.
1670          *
1671          * If SCSI-II tagged queuing is enabled, we also send a SIMPLE_QUEUE_TAG
1672          * message (2 bytes) with a tag ID that we increment with every command
1673          * until it wraps back to 0.
1674          *
1675          * XXX - it turns out that there are some broken SCSI-II devices,
1676          *           which claim to support tagged queuing but fail when more than
1677          *           some number of commands are issued at once.
1678          */
1679
1680         /* Wait for start of REQ/ACK handshake */
1681         while (!(NCR5380_read(STATUS_REG) & SR_REQ))
1682                 ;
1683
1684         SEL_PRINTK("scsi%d: target %d selected, going into MESSAGE OUT phase.\n",
1685                    HOSTNO, cmd->device->id);
1686         tmp[0] = IDENTIFY(1, cmd->device->lun);
1687
1688 #ifdef SUPPORT_TAGS
1689         if (cmd->tag != TAG_NONE) {
1690                 tmp[1] = hostdata->last_message = SIMPLE_QUEUE_TAG;
1691                 tmp[2] = cmd->tag;
1692                 len = 3;
1693         } else
1694                 len = 1;
1695 #else
1696         len = 1;
1697         cmd->tag = 0;
1698 #endif /* SUPPORT_TAGS */
1699
1700         /* Send message(s) */
1701         data = tmp;
1702         phase = PHASE_MSGOUT;
1703         NCR5380_transfer_pio(instance, &phase, &len, &data);
1704         SEL_PRINTK("scsi%d: nexus established.\n", HOSTNO);
1705         /* XXX need to handle errors here */
1706         hostdata->connected = cmd;
1707 #ifndef SUPPORT_TAGS
1708         hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
1709 #endif
1710
1711         initialize_SCp(cmd);
1712
1713         return 0;
1714 }
1715
1716 /*
1717  * Function : int NCR5380_transfer_pio (struct Scsi_Host *instance,
1718  *      unsigned char *phase, int *count, unsigned char **data)
1719  *
1720  * Purpose : transfers data in given phase using polled I/O
1721  *
1722  * Inputs : instance - instance of driver, *phase - pointer to
1723  *      what phase is expected, *count - pointer to number of
1724  *      bytes to transfer, **data - pointer to data pointer.
1725  *
1726  * Returns : -1 when different phase is entered without transferring
1727  *      maximum number of bytes, 0 if all bytes are transferred or exit
1728  *      is in same phase.
1729  *
1730  *      Also, *phase, *count, *data are modified in place.
1731  *
1732  * XXX Note : handling for bus free may be useful.
1733  */
1734
1735 /*
1736  * Note : this code is not as quick as it could be, however it
1737  * IS 100% reliable, and for the actual data transfer where speed
1738  * counts, we will always do a pseudo DMA or DMA transfer.
1739  */
1740
1741 static int NCR5380_transfer_pio(struct Scsi_Host *instance,
1742                                 unsigned char *phase, int *count,
1743                                 unsigned char **data)
1744 {
1745         register unsigned char p = *phase, tmp;
1746         register int c = *count;
1747         register unsigned char *d = *data;
1748
1749         /*
1750          * The NCR5380 chip will only drive the SCSI bus when the
1751          * phase specified in the appropriate bits of the TARGET COMMAND
1752          * REGISTER match the STATUS REGISTER
1753          */
1754
1755         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1756
1757         do {
1758                 /*
1759                  * Wait for assertion of REQ, after which the phase bits will be
1760                  * valid
1761                  */
1762                 while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ))
1763                         ;
1764
1765                 HSH_PRINTK("scsi%d: REQ detected\n", HOSTNO);
1766
1767                 /* Check for phase mismatch */
1768                 if ((tmp & PHASE_MASK) != p) {
1769                         PIO_PRINTK("scsi%d: phase mismatch\n", HOSTNO);
1770                         NCR_PRINT_PHASE(NDEBUG_PIO);
1771                         break;
1772                 }
1773
1774                 /* Do actual transfer from SCSI bus to / from memory */
1775                 if (!(p & SR_IO))
1776                         NCR5380_write(OUTPUT_DATA_REG, *d);
1777                 else
1778                         *d = NCR5380_read(CURRENT_SCSI_DATA_REG);
1779
1780                 ++d;
1781
1782                 /*
1783                  * The SCSI standard suggests that in MSGOUT phase, the initiator
1784                  * should drop ATN on the last byte of the message phase
1785                  * after REQ has been asserted for the handshake but before
1786                  * the initiator raises ACK.
1787                  */
1788
1789                 if (!(p & SR_IO)) {
1790                         if (!((p & SR_MSG) && c > 1)) {
1791                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1792                                 NCR_PRINT(NDEBUG_PIO);
1793                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1794                                               ICR_ASSERT_DATA | ICR_ASSERT_ACK);
1795                         } else {
1796                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1797                                               ICR_ASSERT_DATA | ICR_ASSERT_ATN);
1798                                 NCR_PRINT(NDEBUG_PIO);
1799                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
1800                                               ICR_ASSERT_DATA | ICR_ASSERT_ATN | ICR_ASSERT_ACK);
1801                         }
1802                 } else {
1803                         NCR_PRINT(NDEBUG_PIO);
1804                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ACK);
1805                 }
1806
1807                 while (NCR5380_read(STATUS_REG) & SR_REQ)
1808                         ;
1809
1810                 HSH_PRINTK("scsi%d: req false, handshake complete\n", HOSTNO);
1811
1812                 /*
1813                  * We have several special cases to consider during REQ/ACK handshaking :
1814                  * 1.  We were in MSGOUT phase, and we are on the last byte of the
1815                  *      message.  ATN must be dropped as ACK is dropped.
1816                  *
1817                  * 2.  We are in a MSGIN phase, and we are on the last byte of the
1818                  *      message.  We must exit with ACK asserted, so that the calling
1819                  *      code may raise ATN before dropping ACK to reject the message.
1820                  *
1821                  * 3.  ACK and ATN are clear and the target may proceed as normal.
1822                  */
1823                 if (!(p == PHASE_MSGIN && c == 1)) {
1824                         if (p == PHASE_MSGOUT && c > 1)
1825                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1826                         else
1827                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
1828                 }
1829         } while (--c);
1830
1831         PIO_PRINTK("scsi%d: residual %d\n", HOSTNO, c);
1832
1833         *count = c;
1834         *data = d;
1835         tmp = NCR5380_read(STATUS_REG);
1836         /* The phase read from the bus is valid if either REQ is (already)
1837          * asserted or if ACK hasn't been released yet. The latter is the case if
1838          * we're in MSGIN and all wanted bytes have been received.
1839          */
1840         if ((tmp & SR_REQ) || (p == PHASE_MSGIN && c == 0))
1841                 *phase = tmp & PHASE_MASK;
1842         else
1843                 *phase = PHASE_UNKNOWN;
1844
1845         if (!c || (*phase == p))
1846                 return 0;
1847         else
1848                 return -1;
1849 }
1850
1851 /*
1852  * Function : do_abort (Scsi_Host *host)
1853  *
1854  * Purpose : abort the currently established nexus.  Should only be
1855  *      called from a routine which can drop into a
1856  *
1857  * Returns : 0 on success, -1 on failure.
1858  */
1859
1860 static int do_abort(struct Scsi_Host *host)
1861 {
1862         unsigned char tmp, *msgptr, phase;
1863         int len;
1864
1865         /* Request message out phase */
1866         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1867
1868         /*
1869          * Wait for the target to indicate a valid phase by asserting
1870          * REQ.  Once this happens, we'll have either a MSGOUT phase
1871          * and can immediately send the ABORT message, or we'll have some
1872          * other phase and will have to source/sink data.
1873          *
1874          * We really don't care what value was on the bus or what value
1875          * the target sees, so we just handshake.
1876          */
1877
1878         while (!((tmp = NCR5380_read(STATUS_REG)) & SR_REQ))
1879                 ;
1880
1881         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
1882
1883         if ((tmp & PHASE_MASK) != PHASE_MSGOUT) {
1884                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
1885                               ICR_ASSERT_ACK);
1886                 while (NCR5380_read(STATUS_REG) & SR_REQ)
1887                         ;
1888                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
1889         }
1890
1891         tmp = ABORT;
1892         msgptr = &tmp;
1893         len = 1;
1894         phase = PHASE_MSGOUT;
1895         NCR5380_transfer_pio(host, &phase, &len, &msgptr);
1896
1897         /*
1898          * If we got here, and the command completed successfully,
1899          * we're about to go into bus free state.
1900          */
1901
1902         return len ? -1 : 0;
1903 }
1904
1905 #if defined(REAL_DMA)
1906 /*
1907  * Function : int NCR5380_transfer_dma (struct Scsi_Host *instance,
1908  *      unsigned char *phase, int *count, unsigned char **data)
1909  *
1910  * Purpose : transfers data in given phase using either real
1911  *      or pseudo DMA.
1912  *
1913  * Inputs : instance - instance of driver, *phase - pointer to
1914  *      what phase is expected, *count - pointer to number of
1915  *      bytes to transfer, **data - pointer to data pointer.
1916  *
1917  * Returns : -1 when different phase is entered without transferring
1918  *      maximum number of bytes, 0 if all bytes or transferred or exit
1919  *      is in same phase.
1920  *
1921  *      Also, *phase, *count, *data are modified in place.
1922  *
1923  */
1924
1925
1926 static int NCR5380_transfer_dma(struct Scsi_Host *instance,
1927                                 unsigned char *phase, int *count,
1928                                 unsigned char **data)
1929 {
1930         SETUP_HOSTDATA(instance);
1931         register int c = *count;
1932         register unsigned char p = *phase;
1933         register unsigned char *d = *data;
1934         unsigned char tmp;
1935         unsigned long flags;
1936
1937         if ((tmp = (NCR5380_read(STATUS_REG) & PHASE_MASK)) != p) {
1938                 *phase = tmp;
1939                 return -1;
1940         }
1941
1942         if (atari_read_overruns && (p & SR_IO))
1943                 c -= atari_read_overruns;
1944
1945         DMA_PRINTK("scsi%d: initializing DMA for %s, %d bytes %s %p\n",
1946                    HOSTNO, (p & SR_IO) ? "reading" : "writing",
1947                    c, (p & SR_IO) ? "to" : "from", d);
1948
1949         NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(p));
1950
1951 #ifdef REAL_DMA
1952         NCR5380_write(MODE_REG, MR_BASE | MR_DMA_MODE | MR_ENABLE_EOP_INTR | MR_MONITOR_BSY);
1953 #endif /* def REAL_DMA  */
1954
1955         if (IS_A_TT()) {
1956                 /* On the Medusa, it is a must to initialize the DMA before
1957                  * starting the NCR. This is also the cleaner way for the TT.
1958                  */
1959                 local_irq_save(flags);
1960                 hostdata->dma_len = (p & SR_IO) ?
1961                         NCR5380_dma_read_setup(instance, d, c) :
1962                         NCR5380_dma_write_setup(instance, d, c);
1963                 local_irq_restore(flags);
1964         }
1965
1966         if (p & SR_IO)
1967                 NCR5380_write(START_DMA_INITIATOR_RECEIVE_REG, 0);
1968         else {
1969                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_DATA);
1970                 NCR5380_write(START_DMA_SEND_REG, 0);
1971         }
1972
1973         if (!IS_A_TT()) {
1974                 /* On the Falcon, the DMA setup must be done after the last */
1975                 /* NCR access, else the DMA setup gets trashed!
1976                  */
1977                 local_irq_save(flags);
1978                 hostdata->dma_len = (p & SR_IO) ?
1979                         NCR5380_dma_read_setup(instance, d, c) :
1980                         NCR5380_dma_write_setup(instance, d, c);
1981                 local_irq_restore(flags);
1982         }
1983         return 0;
1984 }
1985 #endif /* defined(REAL_DMA) */
1986
1987 /*
1988  * Function : NCR5380_information_transfer (struct Scsi_Host *instance)
1989  *
1990  * Purpose : run through the various SCSI phases and do as the target
1991  *      directs us to.  Operates on the currently connected command,
1992  *      instance->connected.
1993  *
1994  * Inputs : instance, instance for which we are doing commands
1995  *
1996  * Side effects : SCSI things happen, the disconnected queue will be
1997  *      modified if a command disconnects, *instance->connected will
1998  *      change.
1999  *
2000  * XXX Note : we need to watch for bus free or a reset condition here
2001  *      to recover from an unexpected bus free condition.
2002  */
2003
2004 static void NCR5380_information_transfer(struct Scsi_Host *instance)
2005 {
2006         SETUP_HOSTDATA(instance);
2007         unsigned long flags;
2008         unsigned char msgout = NOP;
2009         int sink = 0;
2010         int len;
2011 #if defined(REAL_DMA)
2012         int transfersize;
2013 #endif
2014         unsigned char *data;
2015         unsigned char phase, tmp, extended_msg[10], old_phase = 0xff;
2016         Scsi_Cmnd *cmd = (Scsi_Cmnd *) hostdata->connected;
2017
2018         while (1) {
2019                 tmp = NCR5380_read(STATUS_REG);
2020                 /* We only have a valid SCSI phase when REQ is asserted */
2021                 if (tmp & SR_REQ) {
2022                         phase = (tmp & PHASE_MASK);
2023                         if (phase != old_phase) {
2024                                 old_phase = phase;
2025                                 NCR_PRINT_PHASE(NDEBUG_INFORMATION);
2026                         }
2027
2028                         if (sink && (phase != PHASE_MSGOUT)) {
2029                                 NCR5380_write(TARGET_COMMAND_REG, PHASE_SR_TO_TCR(tmp));
2030
2031                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN |
2032                                               ICR_ASSERT_ACK);
2033                                 while (NCR5380_read(STATUS_REG) & SR_REQ)
2034                                         ;
2035                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
2036                                               ICR_ASSERT_ATN);
2037                                 sink = 0;
2038                                 continue;
2039                         }
2040
2041                         switch (phase) {
2042                         case PHASE_DATAOUT:
2043 #if (NDEBUG & NDEBUG_NO_DATAOUT)
2044                                 printk("scsi%d: NDEBUG_NO_DATAOUT set, attempted DATAOUT "
2045                                        "aborted\n", HOSTNO);
2046                                 sink = 1;
2047                                 do_abort(instance);
2048                                 cmd->result = DID_ERROR << 16;
2049                                 cmd->scsi_done(cmd);
2050                                 return;
2051 #endif
2052                         case PHASE_DATAIN:
2053                                 /*
2054                                  * If there is no room left in the current buffer in the
2055                                  * scatter-gather list, move onto the next one.
2056                                  */
2057
2058                                 if (!cmd->SCp.this_residual && cmd->SCp.buffers_residual) {
2059                                         ++cmd->SCp.buffer;
2060                                         --cmd->SCp.buffers_residual;
2061                                         cmd->SCp.this_residual = cmd->SCp.buffer->length;
2062                                         cmd->SCp.ptr = sg_virt(cmd->SCp.buffer);
2063                                         /* ++roman: Try to merge some scatter-buffers if
2064                                          * they are at contiguous physical addresses.
2065                                          */
2066                                         merge_contiguous_buffers(cmd);
2067                                         INF_PRINTK("scsi%d: %d bytes and %d buffers left\n",
2068                                                    HOSTNO, cmd->SCp.this_residual,
2069                                                    cmd->SCp.buffers_residual);
2070                                 }
2071
2072                                 /*
2073                                  * The preferred transfer method is going to be
2074                                  * PSEUDO-DMA for systems that are strictly PIO,
2075                                  * since we can let the hardware do the handshaking.
2076                                  *
2077                                  * For this to work, we need to know the transfersize
2078                                  * ahead of time, since the pseudo-DMA code will sit
2079                                  * in an unconditional loop.
2080                                  */
2081
2082                                 /* ++roman: I suggest, this should be
2083                                  *   #if def(REAL_DMA)
2084                                  * instead of leaving REAL_DMA out.
2085                                  */
2086
2087 #if defined(REAL_DMA)
2088                                 if (!cmd->device->borken &&
2089                                     (transfersize = NCR5380_dma_xfer_len(instance,cmd,phase)) > 31) {
2090                                         len = transfersize;
2091                                         cmd->SCp.phase = phase;
2092                                         if (NCR5380_transfer_dma(instance, &phase,
2093                                             &len, (unsigned char **)&cmd->SCp.ptr)) {
2094                                                 /*
2095                                                  * If the watchdog timer fires, all future
2096                                                  * accesses to this device will use the
2097                                                  * polled-IO. */
2098                                                 printk(KERN_NOTICE "scsi%d: switching target %d "
2099                                                            "lun %d to slow handshake\n", HOSTNO,
2100                                                            cmd->device->id, cmd->device->lun);
2101                                                 cmd->device->borken = 1;
2102                                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE |
2103                                                         ICR_ASSERT_ATN);
2104                                                 sink = 1;
2105                                                 do_abort(instance);
2106                                                 cmd->result = DID_ERROR << 16;
2107                                                 cmd->scsi_done(cmd);
2108                                                 /* XXX - need to source or sink data here, as appropriate */
2109                                         } else {
2110 #ifdef REAL_DMA
2111                                                 /* ++roman: When using real DMA,
2112                                                  * information_transfer() should return after
2113                                                  * starting DMA since it has nothing more to
2114                                                  * do.
2115                                                  */
2116                                                 return;
2117 #else
2118                                                 cmd->SCp.this_residual -= transfersize - len;
2119 #endif
2120                                         }
2121                                 } else
2122 #endif /* defined(REAL_DMA) */
2123                                         NCR5380_transfer_pio(instance, &phase,
2124                                                              (int *)&cmd->SCp.this_residual,
2125                                                              (unsigned char **)&cmd->SCp.ptr);
2126                                 break;
2127                         case PHASE_MSGIN:
2128                                 len = 1;
2129                                 data = &tmp;
2130                                 NCR5380_write(SELECT_ENABLE_REG, 0);    /* disable reselects */
2131                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2132                                 cmd->SCp.Message = tmp;
2133
2134                                 switch (tmp) {
2135                                 /*
2136                                  * Linking lets us reduce the time required to get the
2137                                  * next command out to the device, hopefully this will
2138                                  * mean we don't waste another revolution due to the delays
2139                                  * required by ARBITRATION and another SELECTION.
2140                                  *
2141                                  * In the current implementation proposal, low level drivers
2142                                  * merely have to start the next command, pointed to by
2143                                  * next_link, done() is called as with unlinked commands.
2144                                  */
2145 #ifdef LINKED
2146                                 case LINKED_CMD_COMPLETE:
2147                                 case LINKED_FLG_CMD_COMPLETE:
2148                                         /* Accept message by clearing ACK */
2149                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2150
2151                                         LNK_PRINTK("scsi%d: target %d lun %d linked command "
2152                                                    "complete.\n", HOSTNO, cmd->device->id, cmd->device->lun);
2153
2154                                         /* Enable reselect interrupts */
2155                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2156                                         /*
2157                                          * Sanity check : A linked command should only terminate
2158                                          * with one of these messages if there are more linked
2159                                          * commands available.
2160                                          */
2161
2162                                         if (!cmd->next_link) {
2163                                                  printk(KERN_NOTICE "scsi%d: target %d lun %d "
2164                                                         "linked command complete, no next_link\n",
2165                                                         HOSTNO, cmd->device->id, cmd->device->lun);
2166                                                 sink = 1;
2167                                                 do_abort(instance);
2168                                                 return;
2169                                         }
2170
2171                                         initialize_SCp(cmd->next_link);
2172                                         /* The next command is still part of this process; copy it
2173                                          * and don't free it! */
2174                                         cmd->next_link->tag = cmd->tag;
2175                                         cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2176                                         LNK_PRINTK("scsi%d: target %d lun %d linked request "
2177                                                    "done, calling scsi_done().\n",
2178                                                    HOSTNO, cmd->device->id, cmd->device->lun);
2179 #ifdef NCR5380_STATS
2180                                         collect_stats(hostdata, cmd);
2181 #endif
2182                                         cmd->scsi_done(cmd);
2183                                         cmd = hostdata->connected;
2184                                         break;
2185 #endif /* def LINKED */
2186                                 case ABORT:
2187                                 case COMMAND_COMPLETE:
2188                                         /* Accept message by clearing ACK */
2189                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2190                                         /* ++guenther: possible race with Falcon locking */
2191                                         falcon_dont_release++;
2192                                         hostdata->connected = NULL;
2193                                         QU_PRINTK("scsi%d: command for target %d, lun %d "
2194                                                   "completed\n", HOSTNO, cmd->device->id, cmd->device->lun);
2195 #ifdef SUPPORT_TAGS
2196                                         cmd_free_tag(cmd);
2197                                         if (status_byte(cmd->SCp.Status) == QUEUE_FULL) {
2198                                                 /* Turn a QUEUE FULL status into BUSY, I think the
2199                                                  * mid level cannot handle QUEUE FULL :-( (The
2200                                                  * command is retried after BUSY). Also update our
2201                                                  * queue size to the number of currently issued
2202                                                  * commands now.
2203                                                  */
2204                                                 /* ++Andreas: the mid level code knows about
2205                                                    QUEUE_FULL now. */
2206                                                 TAG_ALLOC *ta = &TagAlloc[cmd->device->id][cmd->device->lun];
2207                                                 TAG_PRINTK("scsi%d: target %d lun %d returned "
2208                                                            "QUEUE_FULL after %d commands\n",
2209                                                            HOSTNO, cmd->device->id, cmd->device->lun,
2210                                                            ta->nr_allocated);
2211                                                 if (ta->queue_size > ta->nr_allocated)
2212                                                         ta->nr_allocated = ta->queue_size;
2213                                         }
2214 #else
2215                                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2216 #endif
2217                                         /* Enable reselect interrupts */
2218                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2219
2220                                         /*
2221                                          * I'm not sure what the correct thing to do here is :
2222                                          *
2223                                          * If the command that just executed is NOT a request
2224                                          * sense, the obvious thing to do is to set the result
2225                                          * code to the values of the stored parameters.
2226                                          *
2227                                          * If it was a REQUEST SENSE command, we need some way to
2228                                          * differentiate between the failure code of the original
2229                                          * and the failure code of the REQUEST sense - the obvious
2230                                          * case is success, where we fall through and leave the
2231                                          * result code unchanged.
2232                                          *
2233                                          * The non-obvious place is where the REQUEST SENSE failed
2234                                          */
2235
2236                                         if (cmd->cmnd[0] != REQUEST_SENSE)
2237                                                 cmd->result = cmd->SCp.Status | (cmd->SCp.Message << 8);
2238                                         else if (status_byte(cmd->SCp.Status) != GOOD)
2239                                                 cmd->result = (cmd->result & 0x00ffff) | (DID_ERROR << 16);
2240
2241 #ifdef AUTOSENSE
2242                                         if ((cmd->cmnd[0] == REQUEST_SENSE) &&
2243                                                 hostdata->ses.cmd_len) {
2244                                                 scsi_eh_restore_cmnd(cmd, &hostdata->ses);
2245                                                 hostdata->ses.cmd_len = 0 ;
2246                                         }
2247
2248                                         if ((cmd->cmnd[0] != REQUEST_SENSE) &&
2249                                             (status_byte(cmd->SCp.Status) == CHECK_CONDITION)) {
2250                                                 scsi_eh_prep_cmnd(cmd, &hostdata->ses, NULL, 0, ~0);
2251
2252                                                 ASEN_PRINTK("scsi%d: performing request sense\n", HOSTNO);
2253
2254                                                 local_irq_save(flags);
2255                                                 LIST(cmd,hostdata->issue_queue);
2256                                                 SET_NEXT(cmd, hostdata->issue_queue);
2257                                                 hostdata->issue_queue = (Scsi_Cmnd *) cmd;
2258                                                 local_irq_restore(flags);
2259                                                 QU_PRINTK("scsi%d: REQUEST SENSE added to head of "
2260                                                           "issue queue\n", H_NO(cmd));
2261                                         } else
2262 #endif /* def AUTOSENSE */
2263                                         {
2264 #ifdef NCR5380_STATS
2265                                                 collect_stats(hostdata, cmd);
2266 #endif
2267                                                 cmd->scsi_done(cmd);
2268                                         }
2269
2270                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2271                                         /*
2272                                          * Restore phase bits to 0 so an interrupted selection,
2273                                          * arbitration can resume.
2274                                          */
2275                                         NCR5380_write(TARGET_COMMAND_REG, 0);
2276
2277                                         while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2278                                                 barrier();
2279
2280                                         falcon_dont_release--;
2281                                         /* ++roman: For Falcon SCSI, release the lock on the
2282                                          * ST-DMA here if no other commands are waiting on the
2283                                          * disconnected queue.
2284                                          */
2285                                         falcon_release_lock_if_possible(hostdata);
2286                                         return;
2287                                 case MESSAGE_REJECT:
2288                                         /* Accept message by clearing ACK */
2289                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2290                                         /* Enable reselect interrupts */
2291                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2292                                         switch (hostdata->last_message) {
2293                                         case HEAD_OF_QUEUE_TAG:
2294                                         case ORDERED_QUEUE_TAG:
2295                                         case SIMPLE_QUEUE_TAG:
2296                                                 /* The target obviously doesn't support tagged
2297                                                  * queuing, even though it announced this ability in
2298                                                  * its INQUIRY data ?!? (maybe only this LUN?) Ok,
2299                                                  * clear 'tagged_supported' and lock the LUN, since
2300                                                  * the command is treated as untagged further on.
2301                                                  */
2302                                                 cmd->device->tagged_supported = 0;
2303                                                 hostdata->busy[cmd->device->id] |= (1 << cmd->device->lun);
2304                                                 cmd->tag = TAG_NONE;
2305                                                 TAG_PRINTK("scsi%d: target %d lun %d rejected "
2306                                                            "QUEUE_TAG message; tagged queuing "
2307                                                            "disabled\n",
2308                                                            HOSTNO, cmd->device->id, cmd->device->lun);
2309                                                 break;
2310                                         }
2311                                         break;
2312                                 case DISCONNECT:
2313                                         /* Accept message by clearing ACK */
2314                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2315                                         local_irq_save(flags);
2316                                         cmd->device->disconnect = 1;
2317                                         LIST(cmd,hostdata->disconnected_queue);
2318                                         SET_NEXT(cmd, hostdata->disconnected_queue);
2319                                         hostdata->connected = NULL;
2320                                         hostdata->disconnected_queue = cmd;
2321                                         local_irq_restore(flags);
2322                                         QU_PRINTK("scsi%d: command for target %d lun %d was "
2323                                                   "moved from connected to the "
2324                                                   "disconnected_queue\n", HOSTNO,
2325                                                   cmd->device->id, cmd->device->lun);
2326                                         /*
2327                                          * Restore phase bits to 0 so an interrupted selection,
2328                                          * arbitration can resume.
2329                                          */
2330                                         NCR5380_write(TARGET_COMMAND_REG, 0);
2331
2332                                         /* Enable reselect interrupts */
2333                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2334                                         /* Wait for bus free to avoid nasty timeouts */
2335                                         while ((NCR5380_read(STATUS_REG) & SR_BSY) && !hostdata->connected)
2336                                                 barrier();
2337                                         return;
2338                                         /*
2339                                          * The SCSI data pointer is *IMPLICITLY* saved on a disconnect
2340                                          * operation, in violation of the SCSI spec so we can safely
2341                                          * ignore SAVE/RESTORE pointers calls.
2342                                          *
2343                                          * Unfortunately, some disks violate the SCSI spec and
2344                                          * don't issue the required SAVE_POINTERS message before
2345                                          * disconnecting, and we have to break spec to remain
2346                                          * compatible.
2347                                          */
2348                                 case SAVE_POINTERS:
2349                                 case RESTORE_POINTERS:
2350                                         /* Accept message by clearing ACK */
2351                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2352                                         /* Enable reselect interrupts */
2353                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2354                                         break;
2355                                 case EXTENDED_MESSAGE:
2356                                         /*
2357                                          * Extended messages are sent in the following format :
2358                                          * Byte
2359                                          * 0            EXTENDED_MESSAGE == 1
2360                                          * 1            length (includes one byte for code, doesn't
2361                                          *              include first two bytes)
2362                                          * 2            code
2363                                          * 3..length+1  arguments
2364                                          *
2365                                          * Start the extended message buffer with the EXTENDED_MESSAGE
2366                                          * byte, since spi_print_msg() wants the whole thing.
2367                                          */
2368                                         extended_msg[0] = EXTENDED_MESSAGE;
2369                                         /* Accept first byte by clearing ACK */
2370                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2371
2372                                         EXT_PRINTK("scsi%d: receiving extended message\n", HOSTNO);
2373
2374                                         len = 2;
2375                                         data = extended_msg + 1;
2376                                         phase = PHASE_MSGIN;
2377                                         NCR5380_transfer_pio(instance, &phase, &len, &data);
2378                                         EXT_PRINTK("scsi%d: length=%d, code=0x%02x\n", HOSTNO,
2379                                                    (int)extended_msg[1], (int)extended_msg[2]);
2380
2381                                         if (!len && extended_msg[1] <=
2382                                             (sizeof(extended_msg) - 1)) {
2383                                                 /* Accept third byte by clearing ACK */
2384                                                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2385                                                 len = extended_msg[1] - 1;
2386                                                 data = extended_msg + 3;
2387                                                 phase = PHASE_MSGIN;
2388
2389                                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2390                                                 EXT_PRINTK("scsi%d: message received, residual %d\n",
2391                                                            HOSTNO, len);
2392
2393                                                 switch (extended_msg[2]) {
2394                                                 case EXTENDED_SDTR:
2395                                                 case EXTENDED_WDTR:
2396                                                 case EXTENDED_MODIFY_DATA_POINTER:
2397                                                 case EXTENDED_EXTENDED_IDENTIFY:
2398                                                         tmp = 0;
2399                                                 }
2400                                         } else if (len) {
2401                                                 printk(KERN_NOTICE "scsi%d: error receiving "
2402                                                        "extended message\n", HOSTNO);
2403                                                 tmp = 0;
2404                                         } else {
2405                                                 printk(KERN_NOTICE "scsi%d: extended message "
2406                                                            "code %02x length %d is too long\n",
2407                                                            HOSTNO, extended_msg[2], extended_msg[1]);
2408                                                 tmp = 0;
2409                                         }
2410                                         /* Fall through to reject message */
2411
2412                                         /*
2413                                          * If we get something weird that we aren't expecting,
2414                                          * reject it.
2415                                          */
2416                                 default:
2417                                         if (!tmp) {
2418                                                 printk(KERN_DEBUG "scsi%d: rejecting message ", HOSTNO);
2419                                                 spi_print_msg(extended_msg);
2420                                                 printk("\n");
2421                                         } else if (tmp != EXTENDED_MESSAGE)
2422                                                 printk(KERN_DEBUG "scsi%d: rejecting unknown "
2423                                                        "message %02x from target %d, lun %d\n",
2424                                                        HOSTNO, tmp, cmd->device->id, cmd->device->lun);
2425                                         else
2426                                                 printk(KERN_DEBUG "scsi%d: rejecting unknown "
2427                                                        "extended message "
2428                                                        "code %02x, length %d from target %d, lun %d\n",
2429                                                        HOSTNO, extended_msg[1], extended_msg[0],
2430                                                        cmd->device->id, cmd->device->lun);
2431
2432
2433                                         msgout = MESSAGE_REJECT;
2434                                         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_ATN);
2435                                         break;
2436                                 } /* switch (tmp) */
2437                                 break;
2438                         case PHASE_MSGOUT:
2439                                 len = 1;
2440                                 data = &msgout;
2441                                 hostdata->last_message = msgout;
2442                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2443                                 if (msgout == ABORT) {
2444 #ifdef SUPPORT_TAGS
2445                                         cmd_free_tag(cmd);
2446 #else
2447                                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2448 #endif
2449                                         hostdata->connected = NULL;
2450                                         cmd->result = DID_ERROR << 16;
2451 #ifdef NCR5380_STATS
2452                                         collect_stats(hostdata, cmd);
2453 #endif
2454                                         cmd->scsi_done(cmd);
2455                                         NCR5380_write(SELECT_ENABLE_REG, hostdata->id_mask);
2456                                         falcon_release_lock_if_possible(hostdata);
2457                                         return;
2458                                 }
2459                                 msgout = NOP;
2460                                 break;
2461                         case PHASE_CMDOUT:
2462                                 len = cmd->cmd_len;
2463                                 data = cmd->cmnd;
2464                                 /*
2465                                  * XXX for performance reasons, on machines with a
2466                                  * PSEUDO-DMA architecture we should probably
2467                                  * use the dma transfer function.
2468                                  */
2469                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2470                                 break;
2471                         case PHASE_STATIN:
2472                                 len = 1;
2473                                 data = &tmp;
2474                                 NCR5380_transfer_pio(instance, &phase, &len, &data);
2475                                 cmd->SCp.Status = tmp;
2476                                 break;
2477                         default:
2478                                 printk("scsi%d: unknown phase\n", HOSTNO);
2479                                 NCR_PRINT(NDEBUG_ANY);
2480                         } /* switch(phase) */
2481                 } /* if (tmp * SR_REQ) */
2482         } /* while (1) */
2483 }
2484
2485 /*
2486  * Function : void NCR5380_reselect (struct Scsi_Host *instance)
2487  *
2488  * Purpose : does reselection, initializing the instance->connected
2489  *      field to point to the Scsi_Cmnd for which the I_T_L or I_T_L_Q
2490  *      nexus has been reestablished,
2491  *
2492  * Inputs : instance - this instance of the NCR5380.
2493  *
2494  */
2495
2496
2497 static void NCR5380_reselect(struct Scsi_Host *instance)
2498 {
2499         SETUP_HOSTDATA(instance);
2500         unsigned char target_mask;
2501         unsigned char lun, phase;
2502         int len;
2503 #ifdef SUPPORT_TAGS
2504         unsigned char tag;
2505 #endif
2506         unsigned char msg[3];
2507         unsigned char *data;
2508         Scsi_Cmnd *tmp = NULL, *prev;
2509 /*      unsigned long flags; */
2510
2511         /*
2512          * Disable arbitration, etc. since the host adapter obviously
2513          * lost, and tell an interrupted NCR5380_select() to restart.
2514          */
2515
2516         NCR5380_write(MODE_REG, MR_BASE);
2517         hostdata->restart_select = 1;
2518
2519         target_mask = NCR5380_read(CURRENT_SCSI_DATA_REG) & ~(hostdata->id_mask);
2520
2521         RSL_PRINTK("scsi%d: reselect\n", HOSTNO);
2522
2523         /*
2524          * At this point, we have detected that our SCSI ID is on the bus,
2525          * SEL is true and BSY was false for at least one bus settle delay
2526          * (400 ns).
2527          *
2528          * We must assert BSY ourselves, until the target drops the SEL
2529          * signal.
2530          */
2531
2532         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_BSY);
2533
2534         while (NCR5380_read(STATUS_REG) & SR_SEL)
2535                 ;
2536         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2537
2538         /*
2539          * Wait for target to go into MSGIN.
2540          */
2541
2542         while (!(NCR5380_read(STATUS_REG) & SR_REQ))
2543                 ;
2544
2545         len = 1;
2546         data = msg;
2547         phase = PHASE_MSGIN;
2548         NCR5380_transfer_pio(instance, &phase, &len, &data);
2549
2550         if (!(msg[0] & 0x80)) {
2551                 printk(KERN_DEBUG "scsi%d: expecting IDENTIFY message, got ", HOSTNO);
2552                 spi_print_msg(msg);
2553                 do_abort(instance);
2554                 return;
2555         }
2556         lun = (msg[0] & 0x07);
2557
2558 #ifdef SUPPORT_TAGS
2559         /* If the phase is still MSGIN, the target wants to send some more
2560          * messages. In case it supports tagged queuing, this is probably a
2561          * SIMPLE_QUEUE_TAG for the I_T_L_Q nexus.
2562          */
2563         tag = TAG_NONE;
2564         if (phase == PHASE_MSGIN && setup_use_tagged_queuing) {
2565                 /* Accept previous IDENTIFY message by clearing ACK */
2566                 NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2567                 len = 2;
2568                 data = msg + 1;
2569                 if (!NCR5380_transfer_pio(instance, &phase, &len, &data) &&
2570                     msg[1] == SIMPLE_QUEUE_TAG)
2571                         tag = msg[2];
2572                 TAG_PRINTK("scsi%d: target mask %02x, lun %d sent tag %d at "
2573                            "reselection\n", HOSTNO, target_mask, lun, tag);
2574         }
2575 #endif
2576
2577         /*
2578          * Find the command corresponding to the I_T_L or I_T_L_Q  nexus we
2579          * just reestablished, and remove it from the disconnected queue.
2580          */
2581
2582         for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue, prev = NULL;
2583              tmp; prev = tmp, tmp = NEXT(tmp)) {
2584                 if ((target_mask == (1 << tmp->device->id)) && (lun == tmp->device->lun)
2585 #ifdef SUPPORT_TAGS
2586                     && (tag == tmp->tag)
2587 #endif
2588                     ) {
2589                         /* ++guenther: prevent race with falcon_release_lock */
2590                         falcon_dont_release++;
2591                         if (prev) {
2592                                 REMOVE(prev, NEXT(prev), tmp, NEXT(tmp));
2593                                 SET_NEXT(prev, NEXT(tmp));
2594                         } else {
2595                                 REMOVE(-1, hostdata->disconnected_queue, tmp, NEXT(tmp));
2596                                 hostdata->disconnected_queue = NEXT(tmp);
2597                         }
2598                         SET_NEXT(tmp, NULL);
2599                         break;
2600                 }
2601         }
2602
2603         if (!tmp) {
2604                 printk(KERN_WARNING "scsi%d: warning: target bitmask %02x lun %d "
2605 #ifdef SUPPORT_TAGS
2606                        "tag %d "
2607 #endif
2608                        "not in disconnected_queue.\n",
2609                        HOSTNO, target_mask, lun
2610 #ifdef SUPPORT_TAGS
2611                        , tag
2612 #endif
2613                         );
2614                 /*
2615                  * Since we have an established nexus that we can't do anything
2616                  * with, we must abort it.
2617                  */
2618                 do_abort(instance);
2619                 return;
2620         }
2621
2622         /* Accept message by clearing ACK */
2623         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2624
2625         hostdata->connected = tmp;
2626         RSL_PRINTK("scsi%d: nexus established, target = %d, lun = %d, tag = %d\n",
2627                    HOSTNO, tmp->device->id, tmp->device->lun, tmp->tag);
2628         falcon_dont_release--;
2629 }
2630
2631
2632 /*
2633  * Function : int NCR5380_abort (Scsi_Cmnd *cmd)
2634  *
2635  * Purpose : abort a command
2636  *
2637  * Inputs : cmd - the Scsi_Cmnd to abort, code - code to set the
2638  *      host byte of the result field to, if zero DID_ABORTED is
2639  *      used.
2640  *
2641  * Returns : 0 - success, -1 on failure.
2642  *
2643  * XXX - there is no way to abort the command that is currently
2644  *       connected, you have to wait for it to complete.  If this is
2645  *       a problem, we could implement longjmp() / setjmp(), setjmp()
2646  *       called where the loop started in NCR5380_main().
2647  */
2648
2649 static
2650 int NCR5380_abort(Scsi_Cmnd *cmd)
2651 {
2652         struct Scsi_Host *instance = cmd->device->host;
2653         SETUP_HOSTDATA(instance);
2654         Scsi_Cmnd *tmp, **prev;
2655         unsigned long flags;
2656
2657         printk(KERN_NOTICE "scsi%d: aborting command\n", HOSTNO);
2658         scsi_print_command(cmd);
2659
2660         NCR5380_print_status(instance);
2661
2662         local_irq_save(flags);
2663
2664         if (!IS_A_TT() && !falcon_got_lock)
2665                 printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_abort\n",
2666                        HOSTNO);
2667
2668         ABRT_PRINTK("scsi%d: abort called basr 0x%02x, sr 0x%02x\n", HOSTNO,
2669                     NCR5380_read(BUS_AND_STATUS_REG),
2670                     NCR5380_read(STATUS_REG));
2671
2672 #if 1
2673         /*
2674          * Case 1 : If the command is the currently executing command,
2675          * we'll set the aborted flag and return control so that
2676          * information transfer routine can exit cleanly.
2677          */
2678
2679         if (hostdata->connected == cmd) {
2680
2681                 ABRT_PRINTK("scsi%d: aborting connected command\n", HOSTNO);
2682                 /*
2683                  * We should perform BSY checking, and make sure we haven't slipped
2684                  * into BUS FREE.
2685                  */
2686
2687                 /*      NCR5380_write(INITIATOR_COMMAND_REG, ICR_ASSERT_ATN); */
2688                 /*
2689                  * Since we can't change phases until we've completed the current
2690                  * handshake, we have to source or sink a byte of data if the current
2691                  * phase is not MSGOUT.
2692                  */
2693
2694                 /*
2695                  * Return control to the executing NCR drive so we can clear the
2696                  * aborted flag and get back into our main loop.
2697                  */
2698
2699                 if (do_abort(instance) == 0) {
2700                         hostdata->aborted = 1;
2701                         hostdata->connected = NULL;
2702                         cmd->result = DID_ABORT << 16;
2703 #ifdef SUPPORT_TAGS
2704                         cmd_free_tag(cmd);
2705 #else
2706                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2707 #endif
2708                         local_irq_restore(flags);
2709                         cmd->scsi_done(cmd);
2710                         falcon_release_lock_if_possible(hostdata);
2711                         return SCSI_ABORT_SUCCESS;
2712                 } else {
2713 /*                      local_irq_restore(flags); */
2714                         printk("scsi%d: abort of connected command failed!\n", HOSTNO);
2715                         return SCSI_ABORT_ERROR;
2716                 }
2717         }
2718 #endif
2719
2720         /*
2721          * Case 2 : If the command hasn't been issued yet, we simply remove it
2722          *          from the issue queue.
2723          */
2724         for (prev = (Scsi_Cmnd **)&(hostdata->issue_queue),
2725              tmp = (Scsi_Cmnd *)hostdata->issue_queue;
2726              tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) {
2727                 if (cmd == tmp) {
2728                         REMOVE(5, *prev, tmp, NEXT(tmp));
2729                         (*prev) = NEXT(tmp);
2730                         SET_NEXT(tmp, NULL);
2731                         tmp->result = DID_ABORT << 16;
2732                         local_irq_restore(flags);
2733                         ABRT_PRINTK("scsi%d: abort removed command from issue queue.\n",
2734                                     HOSTNO);
2735                         /* Tagged queuing note: no tag to free here, hasn't been assigned
2736                          * yet... */
2737                         tmp->scsi_done(tmp);
2738                         falcon_release_lock_if_possible(hostdata);
2739                         return SCSI_ABORT_SUCCESS;
2740                 }
2741         }
2742
2743         /*
2744          * Case 3 : If any commands are connected, we're going to fail the abort
2745          *          and let the high level SCSI driver retry at a later time or
2746          *          issue a reset.
2747          *
2748          *          Timeouts, and therefore aborted commands, will be highly unlikely
2749          *          and handling them cleanly in this situation would make the common
2750          *          case of noresets less efficient, and would pollute our code.  So,
2751          *          we fail.
2752          */
2753
2754         if (hostdata->connected) {
2755                 local_irq_restore(flags);
2756                 ABRT_PRINTK("scsi%d: abort failed, command connected.\n", HOSTNO);
2757                 return SCSI_ABORT_SNOOZE;
2758         }
2759
2760         /*
2761          * Case 4: If the command is currently disconnected from the bus, and
2762          *      there are no connected commands, we reconnect the I_T_L or
2763          *      I_T_L_Q nexus associated with it, go into message out, and send
2764          *      an abort message.
2765          *
2766          * This case is especially ugly. In order to reestablish the nexus, we
2767          * need to call NCR5380_select().  The easiest way to implement this
2768          * function was to abort if the bus was busy, and let the interrupt
2769          * handler triggered on the SEL for reselect take care of lost arbitrations
2770          * where necessary, meaning interrupts need to be enabled.
2771          *
2772          * When interrupts are enabled, the queues may change - so we
2773          * can't remove it from the disconnected queue before selecting it
2774          * because that could cause a failure in hashing the nexus if that
2775          * device reselected.
2776          *
2777          * Since the queues may change, we can't use the pointers from when we
2778          * first locate it.
2779          *
2780          * So, we must first locate the command, and if NCR5380_select()
2781          * succeeds, then issue the abort, relocate the command and remove
2782          * it from the disconnected queue.
2783          */
2784
2785         for (tmp = (Scsi_Cmnd *) hostdata->disconnected_queue; tmp;
2786              tmp = NEXT(tmp)) {
2787                 if (cmd == tmp) {
2788                         local_irq_restore(flags);
2789                         ABRT_PRINTK("scsi%d: aborting disconnected command.\n", HOSTNO);
2790
2791                         if (NCR5380_select(instance, cmd, (int)cmd->tag))
2792                                 return SCSI_ABORT_BUSY;
2793
2794                         ABRT_PRINTK("scsi%d: nexus reestablished.\n", HOSTNO);
2795
2796                         do_abort(instance);
2797
2798                         local_irq_save(flags);
2799                         for (prev = (Scsi_Cmnd **)&(hostdata->disconnected_queue),
2800                              tmp = (Scsi_Cmnd *)hostdata->disconnected_queue;
2801                              tmp; prev = NEXTADDR(tmp), tmp = NEXT(tmp)) {
2802                                 if (cmd == tmp) {
2803                                         REMOVE(5, *prev, tmp, NEXT(tmp));
2804                                         *prev = NEXT(tmp);
2805                                         SET_NEXT(tmp, NULL);
2806                                         tmp->result = DID_ABORT << 16;
2807                                         /* We must unlock the tag/LUN immediately here, since the
2808                                          * target goes to BUS FREE and doesn't send us another
2809                                          * message (COMMAND_COMPLETE or the like)
2810                                          */
2811 #ifdef SUPPORT_TAGS
2812                                         cmd_free_tag(tmp);
2813 #else
2814                                         hostdata->busy[cmd->device->id] &= ~(1 << cmd->device->lun);
2815 #endif
2816                                         local_irq_restore(flags);
2817                                         tmp->scsi_done(tmp);
2818                                         falcon_release_lock_if_possible(hostdata);
2819                                         return SCSI_ABORT_SUCCESS;
2820                                 }
2821                         }
2822                 }
2823         }
2824
2825         /*
2826          * Case 5 : If we reached this point, the command was not found in any of
2827          *          the queues.
2828          *
2829          * We probably reached this point because of an unlikely race condition
2830          * between the command completing successfully and the abortion code,
2831          * so we won't panic, but we will notify the user in case something really
2832          * broke.
2833          */
2834
2835         local_irq_restore(flags);
2836         printk(KERN_INFO "scsi%d: warning : SCSI command probably completed successfully before abortion\n", HOSTNO);
2837
2838         /* Maybe it is sufficient just to release the ST-DMA lock... (if
2839          * possible at all) At least, we should check if the lock could be
2840          * released after the abort, in case it is kept due to some bug.
2841          */
2842         falcon_release_lock_if_possible(hostdata);
2843
2844         return SCSI_ABORT_NOT_RUNNING;
2845 }
2846
2847
2848 /*
2849  * Function : int NCR5380_reset (Scsi_Cmnd *cmd)
2850  *
2851  * Purpose : reset the SCSI bus.
2852  *
2853  * Returns : SCSI_RESET_WAKEUP
2854  *
2855  */
2856
2857 static int NCR5380_bus_reset(Scsi_Cmnd *cmd)
2858 {
2859         SETUP_HOSTDATA(cmd->device->host);
2860         int i;
2861         unsigned long flags;
2862 #if 1
2863         Scsi_Cmnd *connected, *disconnected_queue;
2864 #endif
2865
2866         if (!IS_A_TT() && !falcon_got_lock)
2867                 printk(KERN_ERR "scsi%d: !!BINGO!! Falcon has no lock in NCR5380_reset\n",
2868                        H_NO(cmd));
2869
2870         NCR5380_print_status(cmd->device->host);
2871
2872         /* get in phase */
2873         NCR5380_write(TARGET_COMMAND_REG,
2874                       PHASE_SR_TO_TCR(NCR5380_read(STATUS_REG)));
2875         /* assert RST */
2876         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE | ICR_ASSERT_RST);
2877         udelay(40);
2878         /* reset NCR registers */
2879         NCR5380_write(INITIATOR_COMMAND_REG, ICR_BASE);
2880         NCR5380_write(MODE_REG, MR_BASE);
2881         NCR5380_write(TARGET_COMMAND_REG, 0);
2882         NCR5380_write(SELECT_ENABLE_REG, 0);
2883         /* ++roman: reset interrupt condition! otherwise no interrupts don't get
2884          * through anymore ... */
2885         (void)NCR5380_read(RESET_PARITY_INTERRUPT_REG);
2886
2887 #if 1   /* XXX Should now be done by midlevel code, but it's broken XXX */
2888         /* XXX see below                                            XXX */
2889
2890         /* MSch: old-style reset: actually abort all command processing here */
2891
2892         /* After the reset, there are no more connected or disconnected commands
2893          * and no busy units; to avoid problems with re-inserting the commands
2894          * into the issue_queue (via scsi_done()), the aborted commands are
2895          * remembered in local variables first.
2896          */
2897         local_irq_save(flags);
2898         connected = (Scsi_Cmnd *)hostdata->connected;
2899         hostdata->connected = NULL;
2900         disconnected_queue = (Scsi_Cmnd *)hostdata->disconnected_queue;
2901         hostdata->disconnected_queue = NULL;
2902 #ifdef SUPPORT_TAGS
2903         free_all_tags();
2904 #endif
2905         for (i = 0; i < 8; ++i)
2906                 hostdata->busy[i] = 0;
2907 #ifdef REAL_DMA
2908         hostdata->dma_len = 0;
2909 #endif
2910         local_irq_restore(flags);
2911
2912         /* In order to tell the mid-level code which commands were aborted,
2913          * set the command status to DID_RESET and call scsi_done() !!!
2914          * This ultimately aborts processing of these commands in the mid-level.
2915          */
2916
2917         if ((cmd = connected)) {
2918                 ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd));
2919                 cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
2920                 cmd->scsi_done(cmd);
2921         }
2922
2923         for (i = 0; (cmd = disconnected_queue); ++i) {
2924                 disconnected_queue = NEXT(cmd);
2925                 SET_NEXT(cmd, NULL);
2926                 cmd->result = (cmd->result & 0xffff) | (DID_RESET << 16);
2927                 cmd->scsi_done(cmd);
2928         }
2929         if (i > 0)
2930                 ABRT_PRINTK("scsi: reset aborted %d disconnected command(s)\n", i);
2931
2932         /* The Falcon lock should be released after a reset...
2933          */
2934         /* ++guenther: moved to atari_scsi_reset(), to prevent a race between
2935          * unlocking and enabling dma interrupt.
2936          */
2937 /*      falcon_release_lock_if_possible( hostdata );*/
2938
2939         /* since all commands have been explicitly terminated, we need to tell
2940          * the midlevel code that the reset was SUCCESSFUL, and there is no
2941          * need to 'wake up' the commands by a request_sense
2942          */
2943         return SCSI_RESET_SUCCESS | SCSI_RESET_BUS_RESET;
2944 #else /* 1 */
2945
2946         /* MSch: new-style reset handling: let the mid-level do what it can */
2947
2948         /* ++guenther: MID-LEVEL IS STILL BROKEN.
2949          * Mid-level is supposed to requeue all commands that were active on the
2950          * various low-level queues. In fact it does this, but that's not enough
2951          * because all these commands are subject to timeout. And if a timeout
2952          * happens for any removed command, *_abort() is called but all queues
2953          * are now empty. Abort then gives up the falcon lock, which is fatal,
2954          * since the mid-level will queue more commands and must have the lock
2955          * (it's all happening inside timer interrupt handler!!).
2956          * Even worse, abort will return NOT_RUNNING for all those commands not
2957          * on any queue, so they won't be retried ...
2958          *
2959          * Conclusion: either scsi.c disables timeout for all resetted commands
2960          * immediately, or we lose!  As of linux-2.0.20 it doesn't.
2961          */
2962
2963         /* After the reset, there are no more connected or disconnected commands
2964          * and no busy units; so clear the low-level status here to avoid
2965          * conflicts when the mid-level code tries to wake up the affected
2966          * commands!
2967          */
2968
2969         if (hostdata->issue_queue)
2970                 ABRT_PRINTK("scsi%d: reset aborted issued command(s)\n", H_NO(cmd));
2971         if (hostdata->connected)
2972                 ABRT_PRINTK("scsi%d: reset aborted a connected command\n", H_NO(cmd));
2973         if (hostdata->disconnected_queue)
2974                 ABRT_PRINTK("scsi%d: reset aborted disconnected command(s)\n", H_NO(cmd));
2975
2976         local_irq_save(flags);
2977         hostdata->issue_queue = NULL;
2978         hostdata->connected = NULL;
2979         hostdata->disconnected_queue = NULL;
2980 #ifdef SUPPORT_TAGS
2981         free_all_tags();
2982 #endif
2983         for (i = 0; i < 8; ++i)
2984                 hostdata->busy[i] = 0;
2985 #ifdef REAL_DMA
2986         hostdata->dma_len = 0;
2987 #endif
2988         local_irq_restore(flags);
2989
2990         /* we did no complete reset of all commands, so a wakeup is required */
2991         return SCSI_RESET_WAKEUP | SCSI_RESET_BUS_RESET;
2992 #endif /* 1 */
2993 }