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