ef577c8c21826b082c0bac3f81b8ea97d96f650c
[linux-2.6.git] / drivers / scsi / scsi_transport_spi.c
1 /* 
2  *  Parallel SCSI (SPI) transport specific attributes exported to sysfs.
3  *
4  *  Copyright (c) 2003 Silicon Graphics, Inc.  All rights reserved.
5  *  Copyright (c) 2004, 2005 James Bottomley <James.Bottomley@SteelEye.com>
6  *
7  *  This program is free software; you can redistribute it and/or modify
8  *  it under the terms of the GNU General Public License as published by
9  *  the Free Software Foundation; either version 2 of the License, or
10  *  (at your option) any later version.
11  *
12  *  This program is distributed in the hope that it will be useful,
13  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
14  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15  *  GNU General Public License for more details.
16  *
17  *  You should have received a copy of the GNU General Public License
18  *  along with this program; if not, write to the Free Software
19  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
20  */
21 #include <linux/ctype.h>
22 #include <linux/init.h>
23 #include <linux/module.h>
24 #include <linux/workqueue.h>
25 #include <linux/blkdev.h>
26 #include <asm/semaphore.h>
27 #include <scsi/scsi.h>
28 #include "scsi_priv.h"
29 #include <scsi/scsi_device.h>
30 #include <scsi/scsi_host.h>
31 #include <scsi/scsi_cmnd.h>
32 #include <scsi/scsi_eh.h>
33 #include <scsi/scsi_transport.h>
34 #include <scsi/scsi_transport_spi.h>
35
36 #define SPI_PRINTK(x, l, f, a...)       dev_printk(l, &(x)->dev, f , ##a)
37
38 #define SPI_NUM_ATTRS 14        /* increase this if you add attributes */
39 #define SPI_OTHER_ATTRS 1       /* Increase this if you add "always
40                                  * on" attributes */
41 #define SPI_HOST_ATTRS  1
42
43 #define SPI_MAX_ECHO_BUFFER_SIZE        4096
44
45 #define DV_LOOPS        3
46 #define DV_TIMEOUT      (10*HZ)
47 #define DV_RETRIES      3       /* should only need at most 
48                                  * two cc/ua clears */
49
50 /* Private data accessors (keep these out of the header file) */
51 #define spi_dv_pending(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_pending)
52 #define spi_dv_sem(x) (((struct spi_transport_attrs *)&(x)->starget_data)->dv_sem)
53
54 struct spi_internal {
55         struct scsi_transport_template t;
56         struct spi_function_template *f;
57         /* The actual attributes */
58         struct class_device_attribute private_attrs[SPI_NUM_ATTRS];
59         /* The array of null terminated pointers to attributes 
60          * needed by scsi_sysfs.c */
61         struct class_device_attribute *attrs[SPI_NUM_ATTRS + SPI_OTHER_ATTRS + 1];
62         struct class_device_attribute private_host_attrs[SPI_HOST_ATTRS];
63         struct class_device_attribute *host_attrs[SPI_HOST_ATTRS + 1];
64 };
65
66 #define to_spi_internal(tmpl)   container_of(tmpl, struct spi_internal, t)
67
68 static const int ppr_to_ps[] = {
69         /* The PPR values 0-6 are reserved, fill them in when
70          * the committee defines them */
71         -1,                     /* 0x00 */
72         -1,                     /* 0x01 */
73         -1,                     /* 0x02 */
74         -1,                     /* 0x03 */
75         -1,                     /* 0x04 */
76         -1,                     /* 0x05 */
77         -1,                     /* 0x06 */
78          3125,                  /* 0x07 */
79          6250,                  /* 0x08 */
80         12500,                  /* 0x09 */
81         25000,                  /* 0x0a */
82         30300,                  /* 0x0b */
83         50000,                  /* 0x0c */
84 };
85 /* The PPR values at which you calculate the period in ns by multiplying
86  * by 4 */
87 #define SPI_STATIC_PPR  0x0c
88
89 static int sprint_frac(char *dest, int value, int denom)
90 {
91         int frac = value % denom;
92         int result = sprintf(dest, "%d", value / denom);
93
94         if (frac == 0)
95                 return result;
96         dest[result++] = '.';
97
98         do {
99                 denom /= 10;
100                 sprintf(dest + result, "%d", frac / denom);
101                 result++;
102                 frac %= denom;
103         } while (frac);
104
105         dest[result++] = '\0';
106         return result;
107 }
108
109 static int spi_execute(struct scsi_device *sdev, const void *cmd,
110                        enum dma_data_direction dir,
111                        void *buffer, unsigned bufflen,
112                        struct scsi_sense_hdr *sshdr)
113 {
114         int i, result;
115         unsigned char sense[SCSI_SENSE_BUFFERSIZE];
116
117         for(i = 0; i < DV_RETRIES; i++) {
118                 result = scsi_execute(sdev, cmd, dir, buffer, bufflen,
119                                       sense, DV_TIMEOUT, /* retries */ 1,
120                                       REQ_FAILFAST);
121                 if (result & DRIVER_SENSE) {
122                         struct scsi_sense_hdr sshdr_tmp;
123                         if (!sshdr)
124                                 sshdr = &sshdr_tmp;
125
126                         if (scsi_normalize_sense(sense, sizeof(*sense),
127                                                  sshdr)
128                             && sshdr->sense_key == UNIT_ATTENTION)
129                                 continue;
130                 }
131                 break;
132         }
133         return result;
134 }
135
136 static struct {
137         enum spi_signal_type    value;
138         char                    *name;
139 } signal_types[] = {
140         { SPI_SIGNAL_UNKNOWN, "unknown" },
141         { SPI_SIGNAL_SE, "SE" },
142         { SPI_SIGNAL_LVD, "LVD" },
143         { SPI_SIGNAL_HVD, "HVD" },
144 };
145
146 static inline const char *spi_signal_to_string(enum spi_signal_type type)
147 {
148         int i;
149
150         for (i = 0; i < sizeof(signal_types)/sizeof(signal_types[0]); i++) {
151                 if (type == signal_types[i].value)
152                         return signal_types[i].name;
153         }
154         return NULL;
155 }
156 static inline enum spi_signal_type spi_signal_to_value(const char *name)
157 {
158         int i, len;
159
160         for (i = 0; i < sizeof(signal_types)/sizeof(signal_types[0]); i++) {
161                 len =  strlen(signal_types[i].name);
162                 if (strncmp(name, signal_types[i].name, len) == 0 &&
163                     (name[len] == '\n' || name[len] == '\0'))
164                         return signal_types[i].value;
165         }
166         return SPI_SIGNAL_UNKNOWN;
167 }
168
169 static int spi_host_setup(struct transport_container *tc, struct device *dev,
170                           struct class_device *cdev)
171 {
172         struct Scsi_Host *shost = dev_to_shost(dev);
173
174         spi_signalling(shost) = SPI_SIGNAL_UNKNOWN;
175
176         return 0;
177 }
178
179 static DECLARE_TRANSPORT_CLASS(spi_host_class,
180                                "spi_host",
181                                spi_host_setup,
182                                NULL,
183                                NULL);
184
185 static int spi_host_match(struct attribute_container *cont,
186                           struct device *dev)
187 {
188         struct Scsi_Host *shost;
189         struct spi_internal *i;
190
191         if (!scsi_is_host_device(dev))
192                 return 0;
193
194         shost = dev_to_shost(dev);
195         if (!shost->transportt  || shost->transportt->host_attrs.ac.class
196             != &spi_host_class.class)
197                 return 0;
198
199         i = to_spi_internal(shost->transportt);
200         
201         return &i->t.host_attrs.ac == cont;
202 }
203
204 static int spi_device_configure(struct transport_container *tc,
205                                 struct device *dev,
206                                 struct class_device *cdev)
207 {
208         struct scsi_device *sdev = to_scsi_device(dev);
209         struct scsi_target *starget = sdev->sdev_target;
210
211         /* Populate the target capability fields with the values
212          * gleaned from the device inquiry */
213
214         spi_support_sync(starget) = scsi_device_sync(sdev);
215         spi_support_wide(starget) = scsi_device_wide(sdev);
216         spi_support_dt(starget) = scsi_device_dt(sdev);
217         spi_support_dt_only(starget) = scsi_device_dt_only(sdev);
218         spi_support_ius(starget) = scsi_device_ius(sdev);
219         spi_support_qas(starget) = scsi_device_qas(sdev);
220
221         return 0;
222 }
223
224 static int spi_setup_transport_attrs(struct transport_container *tc,
225                                      struct device *dev,
226                                      struct class_device *cdev)
227 {
228         struct scsi_target *starget = to_scsi_target(dev);
229
230         spi_period(starget) = -1;       /* illegal value */
231         spi_min_period(starget) = 0;
232         spi_offset(starget) = 0;        /* async */
233         spi_max_offset(starget) = 255;
234         spi_width(starget) = 0; /* narrow */
235         spi_max_width(starget) = 1;
236         spi_iu(starget) = 0;    /* no IU */
237         spi_dt(starget) = 0;    /* ST */
238         spi_qas(starget) = 0;
239         spi_wr_flow(starget) = 0;
240         spi_rd_strm(starget) = 0;
241         spi_rti(starget) = 0;
242         spi_pcomp_en(starget) = 0;
243         spi_hold_mcs(starget) = 0;
244         spi_dv_pending(starget) = 0;
245         spi_initial_dv(starget) = 0;
246         init_MUTEX(&spi_dv_sem(starget));
247
248         return 0;
249 }
250
251 #define spi_transport_show_simple(field, format_string)                 \
252                                                                         \
253 static ssize_t                                                          \
254 show_spi_transport_##field(struct class_device *cdev, char *buf)        \
255 {                                                                       \
256         struct scsi_target *starget = transport_class_to_starget(cdev); \
257         struct spi_transport_attrs *tp;                                 \
258                                                                         \
259         tp = (struct spi_transport_attrs *)&starget->starget_data;      \
260         return snprintf(buf, 20, format_string, tp->field);             \
261 }
262
263 #define spi_transport_store_simple(field, format_string)                \
264                                                                         \
265 static ssize_t                                                          \
266 store_spi_transport_##field(struct class_device *cdev, const char *buf, \
267                             size_t count)                               \
268 {                                                                       \
269         int val;                                                        \
270         struct scsi_target *starget = transport_class_to_starget(cdev); \
271         struct spi_transport_attrs *tp;                                 \
272                                                                         \
273         tp = (struct spi_transport_attrs *)&starget->starget_data;      \
274         val = simple_strtoul(buf, NULL, 0);                             \
275         tp->field = val;                                                \
276         return count;                                                   \
277 }
278
279 #define spi_transport_show_function(field, format_string)               \
280                                                                         \
281 static ssize_t                                                          \
282 show_spi_transport_##field(struct class_device *cdev, char *buf)        \
283 {                                                                       \
284         struct scsi_target *starget = transport_class_to_starget(cdev); \
285         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);    \
286         struct spi_transport_attrs *tp;                                 \
287         struct spi_internal *i = to_spi_internal(shost->transportt);    \
288         tp = (struct spi_transport_attrs *)&starget->starget_data;      \
289         if (i->f->get_##field)                                          \
290                 i->f->get_##field(starget);                             \
291         return snprintf(buf, 20, format_string, tp->field);             \
292 }
293
294 #define spi_transport_store_function(field, format_string)              \
295 static ssize_t                                                          \
296 store_spi_transport_##field(struct class_device *cdev, const char *buf, \
297                             size_t count)                               \
298 {                                                                       \
299         int val;                                                        \
300         struct scsi_target *starget = transport_class_to_starget(cdev); \
301         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);    \
302         struct spi_internal *i = to_spi_internal(shost->transportt);    \
303                                                                         \
304         val = simple_strtoul(buf, NULL, 0);                             \
305         i->f->set_##field(starget, val);                        \
306         return count;                                                   \
307 }
308
309 #define spi_transport_store_max(field, format_string)                   \
310 static ssize_t                                                          \
311 store_spi_transport_##field(struct class_device *cdev, const char *buf, \
312                             size_t count)                               \
313 {                                                                       \
314         int val;                                                        \
315         struct scsi_target *starget = transport_class_to_starget(cdev); \
316         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);    \
317         struct spi_internal *i = to_spi_internal(shost->transportt);    \
318         struct spi_transport_attrs *tp                                  \
319                 = (struct spi_transport_attrs *)&starget->starget_data; \
320                                                                         \
321         val = simple_strtoul(buf, NULL, 0);                             \
322         if (val > tp->max_##field)                                      \
323                 val = tp->max_##field;                                  \
324         i->f->set_##field(starget, val);                                \
325         return count;                                                   \
326 }
327
328 #define spi_transport_rd_attr(field, format_string)                     \
329         spi_transport_show_function(field, format_string)               \
330         spi_transport_store_function(field, format_string)              \
331 static CLASS_DEVICE_ATTR(field, S_IRUGO | S_IWUSR,                      \
332                          show_spi_transport_##field,                    \
333                          store_spi_transport_##field);
334
335 #define spi_transport_simple_attr(field, format_string)                 \
336         spi_transport_show_simple(field, format_string)                 \
337         spi_transport_store_simple(field, format_string)                \
338 static CLASS_DEVICE_ATTR(field, S_IRUGO | S_IWUSR,                      \
339                          show_spi_transport_##field,                    \
340                          store_spi_transport_##field);
341
342 #define spi_transport_max_attr(field, format_string)                    \
343         spi_transport_show_function(field, format_string)               \
344         spi_transport_store_max(field, format_string)                   \
345         spi_transport_simple_attr(max_##field, format_string)           \
346 static CLASS_DEVICE_ATTR(field, S_IRUGO | S_IWUSR,                      \
347                          show_spi_transport_##field,                    \
348                          store_spi_transport_##field);
349
350 /* The Parallel SCSI Tranport Attributes: */
351 spi_transport_max_attr(offset, "%d\n");
352 spi_transport_max_attr(width, "%d\n");
353 spi_transport_rd_attr(iu, "%d\n");
354 spi_transport_rd_attr(dt, "%d\n");
355 spi_transport_rd_attr(qas, "%d\n");
356 spi_transport_rd_attr(wr_flow, "%d\n");
357 spi_transport_rd_attr(rd_strm, "%d\n");
358 spi_transport_rd_attr(rti, "%d\n");
359 spi_transport_rd_attr(pcomp_en, "%d\n");
360 spi_transport_rd_attr(hold_mcs, "%d\n");
361
362 /* we only care about the first child device so we return 1 */
363 static int child_iter(struct device *dev, void *data)
364 {
365         struct scsi_device *sdev = to_scsi_device(dev);
366
367         spi_dv_device(sdev);
368         return 1;
369 }
370
371 static ssize_t
372 store_spi_revalidate(struct class_device *cdev, const char *buf, size_t count)
373 {
374         struct scsi_target *starget = transport_class_to_starget(cdev);
375
376         device_for_each_child(&starget->dev, NULL, child_iter);
377         return count;
378 }
379 static CLASS_DEVICE_ATTR(revalidate, S_IWUSR, NULL, store_spi_revalidate);
380
381 /* Translate the period into ns according to the current spec
382  * for SDTR/PPR messages */
383 static ssize_t
384 show_spi_transport_period_helper(struct class_device *cdev, char *buf,
385                                  int period)
386 {
387         int len, picosec;
388
389         if (period < 0 || period > 0xff) {
390                 picosec = -1;
391         } else if (period <= SPI_STATIC_PPR) {
392                 picosec = ppr_to_ps[period];
393         } else {
394                 picosec = period * 4000;
395         }
396
397         if (picosec == -1) {
398                 len = sprintf(buf, "reserved");
399         } else {
400                 len = sprint_frac(buf, picosec, 1000);
401         }
402
403         buf[len++] = '\n';
404         buf[len] = '\0';
405         return len;
406 }
407
408 static ssize_t
409 store_spi_transport_period_helper(struct class_device *cdev, const char *buf,
410                                   size_t count, int *periodp)
411 {
412         int j, picosec, period = -1;
413         char *endp;
414
415         picosec = simple_strtoul(buf, &endp, 10) * 1000;
416         if (*endp == '.') {
417                 int mult = 100;
418                 do {
419                         endp++;
420                         if (!isdigit(*endp))
421                                 break;
422                         picosec += (*endp - '0') * mult;
423                         mult /= 10;
424                 } while (mult > 0);
425         }
426
427         for (j = 0; j <= SPI_STATIC_PPR; j++) {
428                 if (ppr_to_ps[j] < picosec)
429                         continue;
430                 period = j;
431                 break;
432         }
433
434         if (period == -1)
435                 period = picosec / 4000;
436
437         if (period > 0xff)
438                 period = 0xff;
439
440         *periodp = period;
441
442         return count;
443 }
444
445 static ssize_t
446 show_spi_transport_period(struct class_device *cdev, char *buf)
447 {
448         struct scsi_target *starget = transport_class_to_starget(cdev);
449         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
450         struct spi_internal *i = to_spi_internal(shost->transportt);
451         struct spi_transport_attrs *tp =
452                 (struct spi_transport_attrs *)&starget->starget_data;
453
454         if (i->f->get_period)
455                 i->f->get_period(starget);
456
457         return show_spi_transport_period_helper(cdev, buf, tp->period);
458 }
459
460 static ssize_t
461 store_spi_transport_period(struct class_device *cdev, const char *buf,
462                             size_t count)
463 {
464         struct scsi_target *starget = transport_class_to_starget(cdev);
465         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
466         struct spi_internal *i = to_spi_internal(shost->transportt);
467         struct spi_transport_attrs *tp =
468                 (struct spi_transport_attrs *)&starget->starget_data;
469         int period, retval;
470
471         retval = store_spi_transport_period_helper(cdev, buf, count, &period);
472
473         if (period < tp->min_period)
474                 period = tp->min_period;
475
476         i->f->set_period(starget, period);
477
478         return retval;
479 }
480
481 static CLASS_DEVICE_ATTR(period, S_IRUGO | S_IWUSR, 
482                          show_spi_transport_period,
483                          store_spi_transport_period);
484
485 static ssize_t
486 show_spi_transport_min_period(struct class_device *cdev, char *buf)
487 {
488         struct scsi_target *starget = transport_class_to_starget(cdev);
489         struct spi_transport_attrs *tp =
490                 (struct spi_transport_attrs *)&starget->starget_data;
491
492         return show_spi_transport_period_helper(cdev, buf, tp->min_period);
493 }
494
495 static ssize_t
496 store_spi_transport_min_period(struct class_device *cdev, const char *buf,
497                             size_t count)
498 {
499         struct scsi_target *starget = transport_class_to_starget(cdev);
500         struct spi_transport_attrs *tp =
501                 (struct spi_transport_attrs *)&starget->starget_data;
502
503         return store_spi_transport_period_helper(cdev, buf, count,
504                                                  &tp->min_period);
505 }
506
507
508 static CLASS_DEVICE_ATTR(min_period, S_IRUGO | S_IWUSR, 
509                          show_spi_transport_min_period,
510                          store_spi_transport_min_period);
511
512
513 static ssize_t show_spi_host_signalling(struct class_device *cdev, char *buf)
514 {
515         struct Scsi_Host *shost = transport_class_to_shost(cdev);
516         struct spi_internal *i = to_spi_internal(shost->transportt);
517
518         if (i->f->get_signalling)
519                 i->f->get_signalling(shost);
520
521         return sprintf(buf, "%s\n", spi_signal_to_string(spi_signalling(shost)));
522 }
523 static ssize_t store_spi_host_signalling(struct class_device *cdev,
524                                          const char *buf, size_t count)
525 {
526         struct Scsi_Host *shost = transport_class_to_shost(cdev);
527         struct spi_internal *i = to_spi_internal(shost->transportt);
528         enum spi_signal_type type = spi_signal_to_value(buf);
529
530         if (type != SPI_SIGNAL_UNKNOWN)
531                 i->f->set_signalling(shost, type);
532
533         return count;
534 }
535 static CLASS_DEVICE_ATTR(signalling, S_IRUGO | S_IWUSR,
536                          show_spi_host_signalling,
537                          store_spi_host_signalling);
538
539 #define DV_SET(x, y)                    \
540         if(i->f->set_##x)               \
541                 i->f->set_##x(sdev->sdev_target, y)
542
543 enum spi_compare_returns {
544         SPI_COMPARE_SUCCESS,
545         SPI_COMPARE_FAILURE,
546         SPI_COMPARE_SKIP_TEST,
547 };
548
549
550 /* This is for read/write Domain Validation:  If the device supports
551  * an echo buffer, we do read/write tests to it */
552 static enum spi_compare_returns
553 spi_dv_device_echo_buffer(struct scsi_device *sdev, u8 *buffer,
554                           u8 *ptr, const int retries)
555 {
556         int len = ptr - buffer;
557         int j, k, r, result;
558         unsigned int pattern = 0x0000ffff;
559         struct scsi_sense_hdr sshdr;
560
561         const char spi_write_buffer[] = {
562                 WRITE_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
563         };
564         const char spi_read_buffer[] = {
565                 READ_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
566         };
567
568         /* set up the pattern buffer.  Doesn't matter if we spill
569          * slightly beyond since that's where the read buffer is */
570         for (j = 0; j < len; ) {
571
572                 /* fill the buffer with counting (test a) */
573                 for ( ; j < min(len, 32); j++)
574                         buffer[j] = j;
575                 k = j;
576                 /* fill the buffer with alternating words of 0x0 and
577                  * 0xffff (test b) */
578                 for ( ; j < min(len, k + 32); j += 2) {
579                         u16 *word = (u16 *)&buffer[j];
580                         
581                         *word = (j & 0x02) ? 0x0000 : 0xffff;
582                 }
583                 k = j;
584                 /* fill with crosstalk (alternating 0x5555 0xaaa)
585                  * (test c) */
586                 for ( ; j < min(len, k + 32); j += 2) {
587                         u16 *word = (u16 *)&buffer[j];
588
589                         *word = (j & 0x02) ? 0x5555 : 0xaaaa;
590                 }
591                 k = j;
592                 /* fill with shifting bits (test d) */
593                 for ( ; j < min(len, k + 32); j += 4) {
594                         u32 *word = (unsigned int *)&buffer[j];
595                         u32 roll = (pattern & 0x80000000) ? 1 : 0;
596                         
597                         *word = pattern;
598                         pattern = (pattern << 1) | roll;
599                 }
600                 /* don't bother with random data (test e) */
601         }
602
603         for (r = 0; r < retries; r++) {
604                 result = spi_execute(sdev, spi_write_buffer, DMA_TO_DEVICE,
605                                      buffer, len, &sshdr);
606                 if(result || !scsi_device_online(sdev)) {
607
608                         scsi_device_set_state(sdev, SDEV_QUIESCE);
609                         if (scsi_sense_valid(&sshdr)
610                             && sshdr.sense_key == ILLEGAL_REQUEST
611                             /* INVALID FIELD IN CDB */
612                             && sshdr.asc == 0x24 && sshdr.ascq == 0x00)
613                                 /* This would mean that the drive lied
614                                  * to us about supporting an echo
615                                  * buffer (unfortunately some Western
616                                  * Digital drives do precisely this)
617                                  */
618                                 return SPI_COMPARE_SKIP_TEST;
619
620
621                         SPI_PRINTK(sdev->sdev_target, KERN_ERR, "Write Buffer failure %x\n", result);
622                         return SPI_COMPARE_FAILURE;
623                 }
624
625                 memset(ptr, 0, len);
626                 spi_execute(sdev, spi_read_buffer, DMA_FROM_DEVICE,
627                             ptr, len, NULL);
628                 scsi_device_set_state(sdev, SDEV_QUIESCE);
629
630                 if (memcmp(buffer, ptr, len) != 0)
631                         return SPI_COMPARE_FAILURE;
632         }
633         return SPI_COMPARE_SUCCESS;
634 }
635
636 /* This is for the simplest form of Domain Validation: a read test
637  * on the inquiry data from the device */
638 static enum spi_compare_returns
639 spi_dv_device_compare_inquiry(struct scsi_device *sdev, u8 *buffer,
640                               u8 *ptr, const int retries)
641 {
642         int r, result;
643         const int len = sdev->inquiry_len;
644         const char spi_inquiry[] = {
645                 INQUIRY, 0, 0, 0, len, 0
646         };
647
648         for (r = 0; r < retries; r++) {
649                 memset(ptr, 0, len);
650
651                 result = spi_execute(sdev, spi_inquiry, DMA_FROM_DEVICE,
652                                      ptr, len, NULL);
653                 
654                 if(result || !scsi_device_online(sdev)) {
655                         scsi_device_set_state(sdev, SDEV_QUIESCE);
656                         return SPI_COMPARE_FAILURE;
657                 }
658
659                 /* If we don't have the inquiry data already, the
660                  * first read gets it */
661                 if (ptr == buffer) {
662                         ptr += len;
663                         --r;
664                         continue;
665                 }
666
667                 if (memcmp(buffer, ptr, len) != 0)
668                         /* failure */
669                         return SPI_COMPARE_FAILURE;
670         }
671         return SPI_COMPARE_SUCCESS;
672 }
673
674 static enum spi_compare_returns
675 spi_dv_retrain(struct scsi_device *sdev, u8 *buffer, u8 *ptr,
676                enum spi_compare_returns 
677                (*compare_fn)(struct scsi_device *, u8 *, u8 *, int))
678 {
679         struct spi_internal *i = to_spi_internal(sdev->host->transportt);
680         struct scsi_target *starget = sdev->sdev_target;
681         int period = 0, prevperiod = 0; 
682         enum spi_compare_returns retval;
683
684
685         for (;;) {
686                 int newperiod;
687                 retval = compare_fn(sdev, buffer, ptr, DV_LOOPS);
688
689                 if (retval == SPI_COMPARE_SUCCESS
690                     || retval == SPI_COMPARE_SKIP_TEST)
691                         break;
692
693                 /* OK, retrain, fallback */
694                 if (i->f->get_iu)
695                         i->f->get_iu(starget);
696                 if (i->f->get_qas)
697                         i->f->get_qas(starget);
698                 if (i->f->get_period)
699                         i->f->get_period(sdev->sdev_target);
700
701                 /* Here's the fallback sequence; first try turning off
702                  * IU, then QAS (if we can control them), then finally
703                  * fall down the periods */
704                 if (i->f->set_iu && spi_iu(starget)) {
705                         SPI_PRINTK(starget, KERN_ERR, "Domain Validation Disabing Information Units\n");
706                         DV_SET(iu, 0);
707                 } else if (i->f->set_qas && spi_qas(starget)) {
708                         SPI_PRINTK(starget, KERN_ERR, "Domain Validation Disabing Quick Arbitration and Selection\n");
709                         DV_SET(qas, 0);
710                 } else {
711                         newperiod = spi_period(starget);
712                         period = newperiod > period ? newperiod : period;
713                         if (period < 0x0d)
714                                 period++;
715                         else
716                                 period += period >> 1;
717
718                         if (unlikely(period > 0xff || period == prevperiod)) {
719                                 /* Total failure; set to async and return */
720                                 SPI_PRINTK(starget, KERN_ERR, "Domain Validation Failure, dropping back to Asynchronous\n");
721                                 DV_SET(offset, 0);
722                                 return SPI_COMPARE_FAILURE;
723                         }
724                         SPI_PRINTK(starget, KERN_ERR, "Domain Validation detected failure, dropping back\n");
725                         DV_SET(period, period);
726                         prevperiod = period;
727                 }
728         }
729         return retval;
730 }
731
732 static int
733 spi_dv_device_get_echo_buffer(struct scsi_device *sdev, u8 *buffer)
734 {
735         int l, result;
736
737         /* first off do a test unit ready.  This can error out 
738          * because of reservations or some other reason.  If it
739          * fails, the device won't let us write to the echo buffer
740          * so just return failure */
741         
742         const char spi_test_unit_ready[] = {
743                 TEST_UNIT_READY, 0, 0, 0, 0, 0
744         };
745
746         const char spi_read_buffer_descriptor[] = {
747                 READ_BUFFER, 0x0b, 0, 0, 0, 0, 0, 0, 4, 0
748         };
749
750         
751         /* We send a set of three TURs to clear any outstanding 
752          * unit attention conditions if they exist (Otherwise the
753          * buffer tests won't be happy).  If the TUR still fails
754          * (reservation conflict, device not ready, etc) just
755          * skip the write tests */
756         for (l = 0; ; l++) {
757                 result = spi_execute(sdev, spi_test_unit_ready, DMA_NONE, 
758                                      NULL, 0, NULL);
759
760                 if(result) {
761                         if(l >= 3)
762                                 return 0;
763                 } else {
764                         /* TUR succeeded */
765                         break;
766                 }
767         }
768
769         result = spi_execute(sdev, spi_read_buffer_descriptor, 
770                              DMA_FROM_DEVICE, buffer, 4, NULL);
771
772         if (result)
773                 /* Device has no echo buffer */
774                 return 0;
775
776         return buffer[3] + ((buffer[2] & 0x1f) << 8);
777 }
778
779 static void
780 spi_dv_device_internal(struct scsi_device *sdev, u8 *buffer)
781 {
782         struct spi_internal *i = to_spi_internal(sdev->host->transportt);
783         struct scsi_target *starget = sdev->sdev_target;
784         int len = sdev->inquiry_len;
785         /* first set us up for narrow async */
786         DV_SET(offset, 0);
787         DV_SET(width, 0);
788         
789         if (spi_dv_device_compare_inquiry(sdev, buffer, buffer, DV_LOOPS)
790             != SPI_COMPARE_SUCCESS) {
791                 SPI_PRINTK(starget, KERN_ERR, "Domain Validation Initial Inquiry Failed\n");
792                 /* FIXME: should probably offline the device here? */
793                 return;
794         }
795
796         /* test width */
797         if (i->f->set_width && spi_max_width(starget) &&
798             scsi_device_wide(sdev)) {
799                 i->f->set_width(starget, 1);
800
801                 if (spi_dv_device_compare_inquiry(sdev, buffer,
802                                                    buffer + len,
803                                                    DV_LOOPS)
804                     != SPI_COMPARE_SUCCESS) {
805                         SPI_PRINTK(starget, KERN_ERR, "Wide Transfers Fail\n");
806                         i->f->set_width(starget, 0);
807                 }
808         }
809
810         if (!i->f->set_period)
811                 return;
812
813         /* device can't handle synchronous */
814         if (!scsi_device_sync(sdev) && !scsi_device_dt(sdev))
815                 return;
816
817         /* see if the device has an echo buffer.  If it does we can
818          * do the SPI pattern write tests */
819
820         len = 0;
821         if (scsi_device_dt(sdev))
822                 len = spi_dv_device_get_echo_buffer(sdev, buffer);
823
824  retry:
825
826         /* now set up to the maximum */
827         DV_SET(offset, spi_max_offset(starget));
828         DV_SET(period, spi_min_period(starget));
829         /* try QAS requests; this should be harmless to set if the
830          * target supports it */
831         if (scsi_device_qas(sdev))
832                 DV_SET(qas, 1);
833         /* Also try IU transfers */
834         if (scsi_device_ius(sdev))
835                 DV_SET(iu, 1);
836         if (spi_min_period(starget) < 9) {
837                 /* This u320 (or u640). Ignore the coupled parameters
838                  * like DT and IU, but set the optional ones */
839                 DV_SET(rd_strm, 1);
840                 DV_SET(wr_flow, 1);
841                 DV_SET(rti, 1);
842                 if (spi_min_period(starget) == 8)
843                         DV_SET(pcomp_en, 1);
844         }
845
846         if (len == 0) {
847                 SPI_PRINTK(starget, KERN_INFO, "Domain Validation skipping write tests\n");
848                 spi_dv_retrain(sdev, buffer, buffer + len,
849                                spi_dv_device_compare_inquiry);
850                 return;
851         }
852
853         if (len > SPI_MAX_ECHO_BUFFER_SIZE) {
854                 SPI_PRINTK(starget, KERN_WARNING, "Echo buffer size %d is too big, trimming to %d\n", len, SPI_MAX_ECHO_BUFFER_SIZE);
855                 len = SPI_MAX_ECHO_BUFFER_SIZE;
856         }
857
858         if (spi_dv_retrain(sdev, buffer, buffer + len,
859                            spi_dv_device_echo_buffer)
860             == SPI_COMPARE_SKIP_TEST) {
861                 /* OK, the stupid drive can't do a write echo buffer
862                  * test after all, fall back to the read tests */
863                 len = 0;
864                 goto retry;
865         }
866 }
867
868
869 /**     spi_dv_device - Do Domain Validation on the device
870  *      @sdev:          scsi device to validate
871  *
872  *      Performs the domain validation on the given device in the
873  *      current execution thread.  Since DV operations may sleep,
874  *      the current thread must have user context.  Also no SCSI
875  *      related locks that would deadlock I/O issued by the DV may
876  *      be held.
877  */
878 void
879 spi_dv_device(struct scsi_device *sdev)
880 {
881         struct scsi_target *starget = sdev->sdev_target;
882         u8 *buffer;
883         const int len = SPI_MAX_ECHO_BUFFER_SIZE*2;
884
885         if (unlikely(scsi_device_get(sdev)))
886                 return;
887
888         buffer = kmalloc(len, GFP_KERNEL);
889
890         if (unlikely(!buffer))
891                 goto out_put;
892
893         memset(buffer, 0, len);
894
895         /* We need to verify that the actual device will quiesce; the
896          * later target quiesce is just a nice to have */
897         if (unlikely(scsi_device_quiesce(sdev)))
898                 goto out_free;
899
900         scsi_target_quiesce(starget);
901
902         spi_dv_pending(starget) = 1;
903         down(&spi_dv_sem(starget));
904
905         SPI_PRINTK(starget, KERN_INFO, "Beginning Domain Validation\n");
906
907         spi_dv_device_internal(sdev, buffer);
908
909         SPI_PRINTK(starget, KERN_INFO, "Ending Domain Validation\n");
910
911         up(&spi_dv_sem(starget));
912         spi_dv_pending(starget) = 0;
913
914         scsi_target_resume(starget);
915
916         spi_initial_dv(starget) = 1;
917
918  out_free:
919         kfree(buffer);
920  out_put:
921         scsi_device_put(sdev);
922 }
923 EXPORT_SYMBOL(spi_dv_device);
924
925 struct work_queue_wrapper {
926         struct work_struct      work;
927         struct scsi_device      *sdev;
928 };
929
930 static void
931 spi_dv_device_work_wrapper(void *data)
932 {
933         struct work_queue_wrapper *wqw = (struct work_queue_wrapper *)data;
934         struct scsi_device *sdev = wqw->sdev;
935
936         kfree(wqw);
937         spi_dv_device(sdev);
938         spi_dv_pending(sdev->sdev_target) = 0;
939         scsi_device_put(sdev);
940 }
941
942
943 /**
944  *      spi_schedule_dv_device - schedule domain validation to occur on the device
945  *      @sdev:  The device to validate
946  *
947  *      Identical to spi_dv_device() above, except that the DV will be
948  *      scheduled to occur in a workqueue later.  All memory allocations
949  *      are atomic, so may be called from any context including those holding
950  *      SCSI locks.
951  */
952 void
953 spi_schedule_dv_device(struct scsi_device *sdev)
954 {
955         struct work_queue_wrapper *wqw =
956                 kmalloc(sizeof(struct work_queue_wrapper), GFP_ATOMIC);
957
958         if (unlikely(!wqw))
959                 return;
960
961         if (unlikely(spi_dv_pending(sdev->sdev_target))) {
962                 kfree(wqw);
963                 return;
964         }
965         /* Set pending early (dv_device doesn't check it, only sets it) */
966         spi_dv_pending(sdev->sdev_target) = 1;
967         if (unlikely(scsi_device_get(sdev))) {
968                 kfree(wqw);
969                 spi_dv_pending(sdev->sdev_target) = 0;
970                 return;
971         }
972
973         INIT_WORK(&wqw->work, spi_dv_device_work_wrapper, wqw);
974         wqw->sdev = sdev;
975
976         schedule_work(&wqw->work);
977 }
978 EXPORT_SYMBOL(spi_schedule_dv_device);
979
980 /**
981  * spi_display_xfer_agreement - Print the current target transfer agreement
982  * @starget: The target for which to display the agreement
983  *
984  * Each SPI port is required to maintain a transfer agreement for each
985  * other port on the bus.  This function prints a one-line summary of
986  * the current agreement; more detailed information is available in sysfs.
987  */
988 void spi_display_xfer_agreement(struct scsi_target *starget)
989 {
990         struct spi_transport_attrs *tp;
991         tp = (struct spi_transport_attrs *)&starget->starget_data;
992
993         if (tp->offset > 0 && tp->period > 0) {
994                 unsigned int picosec, kb100;
995                 char *scsi = "FAST-?";
996                 char tmp[8];
997
998                 if (tp->period <= SPI_STATIC_PPR) {
999                         picosec = ppr_to_ps[tp->period];
1000                         switch (tp->period) {
1001                                 case  7: scsi = "FAST-320"; break;
1002                                 case  8: scsi = "FAST-160"; break;
1003                                 case  9: scsi = "FAST-80"; break;
1004                                 case 10:
1005                                 case 11: scsi = "FAST-40"; break;
1006                                 case 12: scsi = "FAST-20"; break;
1007                         }
1008                 } else {
1009                         picosec = tp->period * 4000;
1010                         if (tp->period < 25)
1011                                 scsi = "FAST-20";
1012                         else if (tp->period < 50)
1013                                 scsi = "FAST-10";
1014                         else
1015                                 scsi = "FAST-5";
1016                 }
1017
1018                 kb100 = (10000000 + picosec / 2) / picosec;
1019                 if (tp->width)
1020                         kb100 *= 2;
1021                 sprint_frac(tmp, picosec, 1000);
1022
1023                 dev_info(&starget->dev,
1024                          "%s %sSCSI %d.%d MB/s %s%s%s%s%s%s%s%s (%s ns, offset %d)\n",
1025                          scsi, tp->width ? "WIDE " : "", kb100/10, kb100 % 10,
1026                          tp->dt ? "DT" : "ST",
1027                          tp->iu ? " IU" : "",
1028                          tp->qas  ? " QAS" : "",
1029                          tp->rd_strm ? " RDSTRM" : "",
1030                          tp->rti ? " RTI" : "",
1031                          tp->wr_flow ? " WRFLOW" : "",
1032                          tp->pcomp_en ? " PCOMP" : "",
1033                          tp->hold_mcs ? " HMCS" : "",
1034                          tmp, tp->offset);
1035         } else {
1036                 dev_info(&starget->dev, "%sasynchronous.\n",
1037                                 tp->width ? "wide " : "");
1038         }
1039 }
1040 EXPORT_SYMBOL(spi_display_xfer_agreement);
1041
1042 #define SETUP_ATTRIBUTE(field)                                          \
1043         i->private_attrs[count] = class_device_attr_##field;            \
1044         if (!i->f->set_##field) {                                       \
1045                 i->private_attrs[count].attr.mode = S_IRUGO;            \
1046                 i->private_attrs[count].store = NULL;                   \
1047         }                                                               \
1048         i->attrs[count] = &i->private_attrs[count];                     \
1049         if (i->f->show_##field)                                         \
1050                 count++
1051
1052 #define SETUP_RELATED_ATTRIBUTE(field, rel_field)                       \
1053         i->private_attrs[count] = class_device_attr_##field;            \
1054         if (!i->f->set_##rel_field) {                                   \
1055                 i->private_attrs[count].attr.mode = S_IRUGO;            \
1056                 i->private_attrs[count].store = NULL;                   \
1057         }                                                               \
1058         i->attrs[count] = &i->private_attrs[count];                     \
1059         if (i->f->show_##rel_field)                                     \
1060                 count++
1061
1062 #define SETUP_HOST_ATTRIBUTE(field)                                     \
1063         i->private_host_attrs[count] = class_device_attr_##field;       \
1064         if (!i->f->set_##field) {                                       \
1065                 i->private_host_attrs[count].attr.mode = S_IRUGO;       \
1066                 i->private_host_attrs[count].store = NULL;              \
1067         }                                                               \
1068         i->host_attrs[count] = &i->private_host_attrs[count];           \
1069         count++
1070
1071 static int spi_device_match(struct attribute_container *cont,
1072                             struct device *dev)
1073 {
1074         struct scsi_device *sdev;
1075         struct Scsi_Host *shost;
1076         struct spi_internal *i;
1077
1078         if (!scsi_is_sdev_device(dev))
1079                 return 0;
1080
1081         sdev = to_scsi_device(dev);
1082         shost = sdev->host;
1083         if (!shost->transportt  || shost->transportt->host_attrs.ac.class
1084             != &spi_host_class.class)
1085                 return 0;
1086         /* Note: this class has no device attributes, so it has
1087          * no per-HBA allocation and thus we don't need to distinguish
1088          * the attribute containers for the device */
1089         i = to_spi_internal(shost->transportt);
1090         if (i->f->deny_binding && i->f->deny_binding(sdev->sdev_target))
1091                 return 0;
1092         return 1;
1093 }
1094
1095 static int spi_target_match(struct attribute_container *cont,
1096                             struct device *dev)
1097 {
1098         struct Scsi_Host *shost;
1099         struct scsi_target *starget;
1100         struct spi_internal *i;
1101
1102         if (!scsi_is_target_device(dev))
1103                 return 0;
1104
1105         shost = dev_to_shost(dev->parent);
1106         if (!shost->transportt  || shost->transportt->host_attrs.ac.class
1107             != &spi_host_class.class)
1108                 return 0;
1109
1110         i = to_spi_internal(shost->transportt);
1111         starget = to_scsi_target(dev);
1112
1113         if (i->f->deny_binding && i->f->deny_binding(starget))
1114                 return 0;
1115
1116         return &i->t.target_attrs.ac == cont;
1117 }
1118
1119 static DECLARE_TRANSPORT_CLASS(spi_transport_class,
1120                                "spi_transport",
1121                                spi_setup_transport_attrs,
1122                                NULL,
1123                                NULL);
1124
1125 static DECLARE_ANON_TRANSPORT_CLASS(spi_device_class,
1126                                     spi_device_match,
1127                                     spi_device_configure);
1128
1129 struct scsi_transport_template *
1130 spi_attach_transport(struct spi_function_template *ft)
1131 {
1132         struct spi_internal *i = kmalloc(sizeof(struct spi_internal),
1133                                          GFP_KERNEL);
1134         int count = 0;
1135         if (unlikely(!i))
1136                 return NULL;
1137
1138         memset(i, 0, sizeof(struct spi_internal));
1139
1140
1141         i->t.target_attrs.ac.class = &spi_transport_class.class;
1142         i->t.target_attrs.ac.attrs = &i->attrs[0];
1143         i->t.target_attrs.ac.match = spi_target_match;
1144         transport_container_register(&i->t.target_attrs);
1145         i->t.target_size = sizeof(struct spi_transport_attrs);
1146         i->t.host_attrs.ac.class = &spi_host_class.class;
1147         i->t.host_attrs.ac.attrs = &i->host_attrs[0];
1148         i->t.host_attrs.ac.match = spi_host_match;
1149         transport_container_register(&i->t.host_attrs);
1150         i->t.host_size = sizeof(struct spi_host_attrs);
1151         i->f = ft;
1152
1153         SETUP_ATTRIBUTE(period);
1154         SETUP_RELATED_ATTRIBUTE(min_period, period);
1155         SETUP_ATTRIBUTE(offset);
1156         SETUP_RELATED_ATTRIBUTE(max_offset, offset);
1157         SETUP_ATTRIBUTE(width);
1158         SETUP_RELATED_ATTRIBUTE(max_width, width);
1159         SETUP_ATTRIBUTE(iu);
1160         SETUP_ATTRIBUTE(dt);
1161         SETUP_ATTRIBUTE(qas);
1162         SETUP_ATTRIBUTE(wr_flow);
1163         SETUP_ATTRIBUTE(rd_strm);
1164         SETUP_ATTRIBUTE(rti);
1165         SETUP_ATTRIBUTE(pcomp_en);
1166         SETUP_ATTRIBUTE(hold_mcs);
1167
1168         /* if you add an attribute but forget to increase SPI_NUM_ATTRS
1169          * this bug will trigger */
1170         BUG_ON(count > SPI_NUM_ATTRS);
1171
1172         i->attrs[count++] = &class_device_attr_revalidate;
1173
1174         i->attrs[count] = NULL;
1175
1176         count = 0;
1177         SETUP_HOST_ATTRIBUTE(signalling);
1178
1179         BUG_ON(count > SPI_HOST_ATTRS);
1180
1181         i->host_attrs[count] = NULL;
1182
1183         return &i->t;
1184 }
1185 EXPORT_SYMBOL(spi_attach_transport);
1186
1187 void spi_release_transport(struct scsi_transport_template *t)
1188 {
1189         struct spi_internal *i = to_spi_internal(t);
1190
1191         transport_container_unregister(&i->t.target_attrs);
1192         transport_container_unregister(&i->t.host_attrs);
1193
1194         kfree(i);
1195 }
1196 EXPORT_SYMBOL(spi_release_transport);
1197
1198 static __init int spi_transport_init(void)
1199 {
1200         int error = transport_class_register(&spi_transport_class);
1201         if (error)
1202                 return error;
1203         error = anon_transport_class_register(&spi_device_class);
1204         return transport_class_register(&spi_host_class);
1205 }
1206
1207 static void __exit spi_transport_exit(void)
1208 {
1209         transport_class_unregister(&spi_transport_class);
1210         anon_transport_class_unregister(&spi_device_class);
1211         transport_class_unregister(&spi_host_class);
1212 }
1213
1214 MODULE_AUTHOR("Martin Hicks");
1215 MODULE_DESCRIPTION("SPI Transport Attributes");
1216 MODULE_LICENSE("GPL");
1217
1218 module_init(spi_transport_init);
1219 module_exit(spi_transport_exit);