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 static ssize_t
 352 store_spi_revalidate(struct class_device *cdev, const char *buf, size_t count)
 353 {
 354         struct scsi_target *starget = transport_class_to_starget(cdev);
 355
 356         /* FIXME: we're relying on an awful lot of device internals
 357          * here.  We really need a function to get the first available
 358          * child */
 359         struct device *dev = container_of(starget->dev.children.next, struct device, node);
 360         struct scsi_device *sdev = to_scsi_device(dev);
 361         spi_dv_device(sdev);
 362         return count;
 363 }
 364 static CLASS_DEVICE_ATTR(revalidate, S_IWUSR, NULL, store_spi_revalidate);
 365
 366 /* Translate the period into ns according to the current spec
 367  * for SDTR/PPR messages */
 368 static ssize_t
 369 show_spi_transport_period_helper(struct class_device *cdev, char *buf,
 370                                  int period)
 371 {
 372         int len, picosec;
 373
 374         if (period < 0 || period > 0xff) {
 375                 picosec = -1;
 376         } else if (period <= SPI_STATIC_PPR) {
 377                 picosec = ppr_to_ps[period];
 378         } else {
 379                 picosec = period * 4000;
 380         }
 381
 382         if (picosec == -1) {
 383                 len = sprintf(buf, "reserved");
 384         } else {
 385                 len = sprint_frac(buf, picosec, 1000);
 386         }
 387
 388         buf[len++] = '\n';
 389         buf[len] = '\0';
 390         return len;
 391 }
 392
 393 static ssize_t
 394 store_spi_transport_period_helper(struct class_device *cdev, const char *buf,
 395                                   size_t count, int *periodp)
 396 {
 397         int j, picosec, period = -1;
 398         char *endp;
 399
 400         picosec = simple_strtoul(buf, &endp, 10) * 1000;
 401         if (*endp == '.') {
 402                 int mult = 100;
 403                 do {
 404                         endp++;
 405                         if (!isdigit(*endp))
 406                                 break;
 407                         picosec += (*endp - '0') * mult;
 408                         mult /= 10;
 409                 } while (mult > 0);
 410         }
 411
 412         for (j = 0; j <= SPI_STATIC_PPR; j++) {
 413                 if (ppr_to_ps[j] < picosec)
 414                         continue;
 415                 period = j;
 416                 break;
 417         }
 418
 419         if (period == -1)
 420                 period = picosec / 4000;
 421
 422         if (period > 0xff)
 423                 period = 0xff;
 424
 425         *periodp = period;
 426
 427         return count;
 428 }
 429
 430 static ssize_t
 431 show_spi_transport_period(struct class_device *cdev, char *buf)
 432 {
 433         struct scsi_target *starget = transport_class_to_starget(cdev);
 434         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
 435         struct spi_internal *i = to_spi_internal(shost->transportt);
 436         struct spi_transport_attrs *tp =
 437                 (struct spi_transport_attrs *)&starget->starget_data;
 438
 439         if (i->f->get_period)
 440                 i->f->get_period(starget);
 441
 442         return show_spi_transport_period_helper(cdev, buf, tp->period);
 443 }
 444
 445 static ssize_t
 446 store_spi_transport_period(struct class_device *cdev, const char *buf,
 447                             size_t count)
 448 {
 449         struct scsi_target *starget = transport_class_to_starget(cdev);
 450         struct Scsi_Host *shost = dev_to_shost(starget->dev.parent);
 451         struct spi_internal *i = to_spi_internal(shost->transportt);
 452         struct spi_transport_attrs *tp =
 453                 (struct spi_transport_attrs *)&starget->starget_data;
 454         int period, retval;
 455
 456         retval = store_spi_transport_period_helper(cdev, buf, count, &period);
 457
 458         if (period < tp->min_period)
 459                 period = tp->min_period;
 460
 461         i->f->set_period(starget, period);
 462
 463         return retval;
 464 }
 465
 466 static CLASS_DEVICE_ATTR(period, S_IRUGO | S_IWUSR,
 467                          show_spi_transport_period,
 468                          store_spi_transport_period);
 469
 470 static ssize_t
 471 show_spi_transport_min_period(struct class_device *cdev, char *buf)
 472 {
 473         struct scsi_target *starget = transport_class_to_starget(cdev);
 474         struct spi_transport_attrs *tp =
 475                 (struct spi_transport_attrs *)&starget->starget_data;
 476
 477         return show_spi_transport_period_helper(cdev, buf, tp->min_period);
 478 }
 479
 480 static ssize_t
 481 store_spi_transport_min_period(struct class_device *cdev, const char *buf,
 482                             size_t count)
 483 {
 484         struct scsi_target *starget = transport_class_to_starget(cdev);
 485         struct spi_transport_attrs *tp =
 486                 (struct spi_transport_attrs *)&starget->starget_data;
 487
 488         return store_spi_transport_period_helper(cdev, buf, count,
 489                                                  &tp->min_period);
 490 }
 491
 492
 493 static CLASS_DEVICE_ATTR(min_period, S_IRUGO | S_IWUSR,
 494                          show_spi_transport_min_period,
 495                          store_spi_transport_min_period);
 496
 497
 498 static ssize_t show_spi_host_signalling(struct class_device *cdev, char *buf)
 499 {
 500         struct Scsi_Host *shost = transport_class_to_shost(cdev);
 501         struct spi_internal *i = to_spi_internal(shost->transportt);
 502
 503         if (i->f->get_signalling)
 504                 i->f->get_signalling(shost);
 505
 506         return sprintf(buf, "%s\n", spi_signal_to_string(spi_signalling(shost)));
 507 }
 508 static ssize_t store_spi_host_signalling(struct class_device *cdev,
 509                                          const char *buf, size_t count)
 510 {
 511         struct Scsi_Host *shost = transport_class_to_shost(cdev);
 512         struct spi_internal *i = to_spi_internal(shost->transportt);
 513         enum spi_signal_type type = spi_signal_to_value(buf);
 514
 515         if (type != SPI_SIGNAL_UNKNOWN)
 516                 i->f->set_signalling(shost, type);
 517
 518         return count;
 519 }
 520 static CLASS_DEVICE_ATTR(signalling, S_IRUGO | S_IWUSR,
 521                          show_spi_host_signalling,
 522                          store_spi_host_signalling);
 523
 524 #define DV_SET(x, y)                    \
 525         if(i->f->set_##x)               \
 526                 i->f->set_##x(sdev->sdev_target, y)
 527
 528 enum spi_compare_returns {
 529         SPI_COMPARE_SUCCESS,
 530         SPI_COMPARE_FAILURE,
 531         SPI_COMPARE_SKIP_TEST,
 532 };
 533
 534
 535 /* This is for read/write Domain Validation:  If the device supports
 536  * an echo buffer, we do read/write tests to it */
 537 static enum spi_compare_returns
 538 spi_dv_device_echo_buffer(struct scsi_request *sreq, u8 *buffer,
 539                           u8 *ptr, const int retries)
 540 {
 541         struct scsi_device *sdev = sreq->sr_device;
 542         int len = ptr - buffer;
 543         int j, k, r;
 544         unsigned int pattern = 0x0000ffff;
 545
 546         const char spi_write_buffer[] = {
 547                 WRITE_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
 548         };
 549         const char spi_read_buffer[] = {
 550                 READ_BUFFER, 0x0a, 0, 0, 0, 0, 0, len >> 8, len & 0xff, 0
 551         };
 552
 553         /* set up the pattern buffer.  Doesn't matter if we spill
 554          * slightly beyond since that's where the read buffer is */
 555         for (j = 0; j < len; ) {
 556
 557                 /* fill the buffer with counting (test a) */
 558                 for ( ; j < min(len, 32); j++)
 559                         buffer[j] = j;
 560                 k = j;
 561                 /* fill the buffer with alternating words of 0x0 and
 562                  * 0xffff (test b) */
 563                 for ( ; j < min(len, k + 32); j += 2) {
 564                         u16 *word = (u16 *)&buffer[j];
 565
 566                         *word = (j & 0x02) ? 0x0000 : 0xffff;
 567                 }
 568                 k = j;
 569                 /* fill with crosstalk (alternating 0x5555 0xaaa)
 570                  * (test c) */
 571                 for ( ; j < min(len, k + 32); j += 2) {
 572                         u16 *word = (u16 *)&buffer[j];
 573
 574                         *word = (j & 0x02) ? 0x5555 : 0xaaaa;
 575                 }
 576                 k = j;
 577                 /* fill with shifting bits (test d) */
 578                 for ( ; j < min(len, k + 32); j += 4) {
 579                         u32 *word = (unsigned int *)&buffer[j];
 580                         u32 roll = (pattern & 0x80000000) ? 1 : 0;
 581
 582                         *word = pattern;
 583                         pattern = (pattern << 1) | roll;
 584                 }
 585                 /* don't bother with random data (test e) */
 586         }
 587
 588         for (r = 0; r < retries; r++) {
 589                 sreq->sr_cmd_len = 0;   /* wait_req to fill in */
 590                 sreq->sr_data_direction = DMA_TO_DEVICE;
 591                 spi_wait_req(sreq, spi_write_buffer, buffer, len);
 592                 if(sreq->sr_result || !scsi_device_online(sdev)) {
 593                         struct scsi_sense_hdr sshdr;
 594
 595                         scsi_device_set_state(sdev, SDEV_QUIESCE);
 596                         if (scsi_request_normalize_sense(sreq, &sshdr)
 597                             && sshdr.sense_key == ILLEGAL_REQUEST
 598                             /* INVALID FIELD IN CDB */
 599                             && sshdr.asc == 0x24 && sshdr.ascq == 0x00)
 600                                 /* This would mean that the drive lied
 601                                  * to us about supporting an echo
 602                                  * buffer (unfortunately some Western
 603                                  * Digital drives do precisely this)
 604                                  */
 605                                 return SPI_COMPARE_SKIP_TEST;
 606
 607
 608                         SPI_PRINTK(sdev->sdev_target, KERN_ERR, "Write Buffer failure %x\n", sreq->sr_result);
 609                         return SPI_COMPARE_FAILURE;
 610                 }
 611
 612                 memset(ptr, 0, len);
 613                 sreq->sr_cmd_len = 0;   /* wait_req to fill in */
 614                 sreq->sr_data_direction = DMA_FROM_DEVICE;
 615                 spi_wait_req(sreq, spi_read_buffer, ptr, len);
 616                 scsi_device_set_state(sdev, SDEV_QUIESCE);
 617
 618                 if (memcmp(buffer, ptr, len) != 0)
 619                         return SPI_COMPARE_FAILURE;
 620         }
 621         return SPI_COMPARE_SUCCESS;
 622 }
 623
 624 /* This is for the simplest form of Domain Validation: a read test
 625  * on the inquiry data from the device */
 626 static enum spi_compare_returns
 627 spi_dv_device_compare_inquiry(struct scsi_request *sreq, u8 *buffer,
 628                               u8 *ptr, const int retries)
 629 {
 630         int r;
 631         const int len = sreq->sr_device->inquiry_len;
 632         struct scsi_device *sdev = sreq->sr_device;
 633         const char spi_inquiry[] = {
 634                 INQUIRY, 0, 0, 0, len, 0
 635         };
 636
 637         for (r = 0; r < retries; r++) {
 638                 sreq->sr_cmd_len = 0;   /* wait_req to fill in */
 639                 sreq->sr_data_direction = DMA_FROM_DEVICE;
 640
 641                 memset(ptr, 0, len);
 642
 643                 spi_wait_req(sreq, spi_inquiry, ptr, len);
 644
 645                 if(sreq->sr_result || !scsi_device_online(sdev)) {
 646                         scsi_device_set_state(sdev, SDEV_QUIESCE);
 647                         return SPI_COMPARE_FAILURE;
 648                 }
 649
 650                 /* If we don't have the inquiry data already, the
 651                  * first read gets it */
 652                 if (ptr == buffer) {
 653                         ptr += len;
 654                         --r;
 655                         continue;
 656                 }
 657
 658                 if (memcmp(buffer, ptr, len) != 0)
 659                         /* failure */
 660                         return SPI_COMPARE_FAILURE;
 661         }
 662         return SPI_COMPARE_SUCCESS;
 663 }
 664
 665 static enum spi_compare_returns
 666 spi_dv_retrain(struct scsi_request *sreq, u8 *buffer, u8 *ptr,
 667                enum spi_compare_returns
 668                (*compare_fn)(struct scsi_request *, u8 *, u8 *, int))
 669 {
 670         struct spi_internal *i = to_spi_internal(sreq->sr_host->transportt);
 671         struct scsi_device *sdev = sreq->sr_device;
 672         struct scsi_target *starget = sdev->sdev_target;
 673         int period = 0, prevperiod = 0;
 674         enum spi_compare_returns retval;
 675
 676
 677         for (;;) {
 678                 int newperiod;
 679                 retval = compare_fn(sreq, buffer, ptr, DV_LOOPS);
 680
 681                 if (retval == SPI_COMPARE_SUCCESS
 682                     || retval == SPI_COMPARE_SKIP_TEST)
 683                         break;
 684
 685                 /* OK, retrain, fallback */
 686                 if (i->f->get_iu)
 687                         i->f->get_iu(starget);
 688                 if (i->f->get_qas)
 689                         i->f->get_qas(starget);
 690                 if (i->f->get_period)
 691                         i->f->get_period(sdev->sdev_target);
 692
 693                 /* Here's the fallback sequence; first try turning off
 694                  * IU, then QAS (if we can control them), then finally
 695                  * fall down the periods */
 696                 if (i->f->set_iu && spi_iu(starget)) {
 697                         SPI_PRINTK(starget, KERN_ERR, "Domain Validation Disabing Information Units\n");
 698                         DV_SET(iu, 0);
 699                 } else if (i->f->set_qas && spi_qas(starget)) {
 700                         SPI_PRINTK(starget, KERN_ERR, "Domain Validation Disabing Quick Arbitration and Selection\n");
 701                         DV_SET(qas, 0);
 702                 } else {
 703                         newperiod = spi_period(starget);
 704                         period = newperiod > period ? newperiod : period;
 705                         if (period < 0x0d)
 706                                 period++;
 707                         else
 708                                 period += period >> 1;
 709
 710                         if (unlikely(period > 0xff || period == prevperiod)) {
 711                                 /* Total failure; set to async and return */
 712                                 SPI_PRINTK(starget, KERN_ERR, "Domain Validation Failure, dropping back to Asynchronous\n");
 713                                 DV_SET(offset, 0);
 714                                 return SPI_COMPARE_FAILURE;
 715                         }
 716                         SPI_PRINTK(starget, KERN_ERR, "Domain Validation detected failure, dropping back\n");
 717                         DV_SET(period, period);
 718                         prevperiod = period;
 719                 }
 720         }
 721         return retval;
 722 }
 723
 724 static int
 725 spi_dv_device_get_echo_buffer(struct scsi_request *sreq, u8 *buffer)
 726 {
 727         int l;
 728
 729         /* first off do a test unit ready.  This can error out
 730          * because of reservations or some other reason.  If it
 731          * fails, the device won't let us write to the echo buffer
 732          * so just return failure */
 733
 734         const char spi_test_unit_ready[] = {
 735                 TEST_UNIT_READY, 0, 0, 0, 0, 0
 736         };
 737
 738         const char spi_read_buffer_descriptor[] = {
 739                 READ_BUFFER, 0x0b, 0, 0, 0, 0, 0, 0, 4, 0
 740         };
 741
 742
 743         sreq->sr_cmd_len = 0;
 744         sreq->sr_data_direction = DMA_NONE;
 745
 746         /* We send a set of three TURs to clear any outstanding
 747          * unit attention conditions if they exist (Otherwise the
 748          * buffer tests won't be happy).  If the TUR still fails
 749          * (reservation conflict, device not ready, etc) just
 750          * skip the write tests */
 751         for (l = 0; ; l++) {
 752                 spi_wait_req(sreq, spi_test_unit_ready, NULL, 0);
 753
 754                 if(sreq->sr_result) {
 755                         if(l >= 3)
 756                                 return 0;
 757                 } else {
 758                         /* TUR succeeded */
 759                         break;
 760                 }
 761         }
 762
 763         sreq->sr_cmd_len = 0;
 764         sreq->sr_data_direction = DMA_FROM_DEVICE;
 765
 766         spi_wait_req(sreq, spi_read_buffer_descriptor, buffer, 4);
 767
 768         if (sreq->sr_result)
 769                 /* Device has no echo buffer */
 770                 return 0;
 771
 772         return buffer[3] + ((buffer[2] & 0x1f) << 8);
 773 }
 774
 775 static void
 776 spi_dv_device_internal(struct scsi_request *sreq, u8 *buffer)
 777 {
 778         struct spi_internal *i = to_spi_internal(sreq->sr_host->transportt);
 779         struct scsi_device *sdev = sreq->sr_device;
 780         struct scsi_target *starget = sdev->sdev_target;
 781         int len = sdev->inquiry_len;
 782         /* first set us up for narrow async */
 783         DV_SET(offset, 0);
 784         DV_SET(width, 0);
 785
 786         if (spi_dv_device_compare_inquiry(sreq, buffer, buffer, DV_LOOPS)
 787             != SPI_COMPARE_SUCCESS) {
 788                 SPI_PRINTK(starget, KERN_ERR, "Domain Validation Initial Inquiry Failed\n");
 789                 /* FIXME: should probably offline the device here? */
 790                 return;
 791         }
 792
 793         /* test width */
 794         if (i->f->set_width && spi_max_width(starget) && sdev->wdtr) {
 795                 i->f->set_width(starget, 1);
 796
 797                 if (spi_dv_device_compare_inquiry(sreq, buffer,
 798                                                    buffer + len,
 799                                                    DV_LOOPS)
 800                     != SPI_COMPARE_SUCCESS) {
 801                         SPI_PRINTK(starget, KERN_ERR, "Wide Transfers Fail\n");
 802                         i->f->set_width(starget, 0);
 803                 }
 804         }
 805
 806         if (!i->f->set_period)
 807                 return;
 808
 809         /* device can't handle synchronous */
 810         if (!sdev->ppr && !sdev->sdtr)
 811                 return;
 812
 813         /* see if the device has an echo buffer.  If it does we can
 814          * do the SPI pattern write tests */
 815
 816         len = 0;
 817         if (sdev->ppr)
 818                 len = spi_dv_device_get_echo_buffer(sreq, buffer);
 819
 820  retry:
 821
 822         /* now set up to the maximum */
 823         DV_SET(offset, spi_max_offset(starget));
 824         DV_SET(period, spi_min_period(starget));
 825         /* try QAS requests; this should be harmless to set if the
 826          * target supports it */
 827         DV_SET(qas, 1);
 828         /* Also try IU transfers */
 829         DV_SET(iu, 1);
 830         if (spi_min_period(starget) < 9) {
 831                 /* This u320 (or u640). Ignore the coupled parameters
 832                  * like DT and IU, but set the optional ones */
 833                 DV_SET(rd_strm, 1);
 834                 DV_SET(wr_flow, 1);
 835                 DV_SET(rti, 1);
 836                 if (spi_min_period(starget) == 8)
 837                         DV_SET(pcomp_en, 1);
 838         }
 839
 840         if (len == 0) {
 841                 SPI_PRINTK(starget, KERN_INFO, "Domain Validation skipping write tests\n");
 842                 spi_dv_retrain(sreq, buffer, buffer + len,
 843                                spi_dv_device_compare_inquiry);
 844                 return;
 845         }
 846
 847         if (len > SPI_MAX_ECHO_BUFFER_SIZE) {
 848                 SPI_PRINTK(starget, KERN_WARNING, "Echo buffer size %d is too big, trimming to %d\n", len, SPI_MAX_ECHO_BUFFER_SIZE);
 849                 len = SPI_MAX_ECHO_BUFFER_SIZE;
 850         }
 851
 852         if (spi_dv_retrain(sreq, buffer, buffer + len,
 853                            spi_dv_device_echo_buffer)
 854             == SPI_COMPARE_SKIP_TEST) {
 855                 /* OK, the stupid drive can't do a write echo buffer
 856                  * test after all, fall back to the read tests */
 857                 len = 0;
 858                 goto retry;
 859         }
 860 }
 861
 862
 863 /**     spi_dv_device - Do Domain Validation on the device
 864  *      @sdev:          scsi device to validate
 865  *
 866  *      Performs the domain validation on the given device in the
 867  *      current execution thread.  Since DV operations may sleep,
 868  *      the current thread must have user context.  Also no SCSI
 869  *      related locks that would deadlock I/O issued by the DV may
 870  *      be held.
 871  */
 872 void
 873 spi_dv_device(struct scsi_device *sdev)
 874 {
 875         struct scsi_request *sreq = scsi_allocate_request(sdev, GFP_KERNEL);
 876         struct scsi_target *starget = sdev->sdev_target;
 877         u8 *buffer;
 878         const int len = SPI_MAX_ECHO_BUFFER_SIZE*2;
 879
 880         if (unlikely(!sreq))
 881                 return;
 882
 883         if (unlikely(scsi_device_get(sdev)))
 884                 goto out_free_req;
 885
 886         buffer = kmalloc(len, GFP_KERNEL);
 887
 888         if (unlikely(!buffer))
 889                 goto out_put;
 890
 891         memset(buffer, 0, len);
 892
 893         /* We need to verify that the actual device will quiesce; the
 894          * later target quiesce is just a nice to have */
 895         if (unlikely(scsi_device_quiesce(sdev)))
 896                 goto out_free;
 897
 898         scsi_target_quiesce(starget);
 899
 900         spi_dv_pending(starget) = 1;
 901         down(&spi_dv_sem(starget));
 902
 903         SPI_PRINTK(starget, KERN_INFO, "Beginning Domain Validation\n");
 904
 905         spi_dv_device_internal(sreq, buffer);
 906
 907         SPI_PRINTK(starget, KERN_INFO, "Ending Domain Validation\n");
 908
 909         up(&spi_dv_sem(starget));
 910         spi_dv_pending(starget) = 0;
 911
 912         scsi_target_resume(starget);
 913
 914         spi_initial_dv(starget) = 1;
 915
 916  out_free:
 917         kfree(buffer);
 918  out_put:
 919         scsi_device_put(sdev);
 920  out_free_req:
 921         scsi_release_request(sreq);
 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 ns, offset %d)\n",
1025                         scsi, tp->width ? "WIDE " : "", kb100/10, kb100 % 10,
1026                         tp->dt ? "DT" : "ST", tp->iu ? " IU" : "",
1027                         tp->qas  ? " QAS" : "", tmp, tp->offset);
1028         } else {
1029                 dev_info(&starget->dev, "%sasynchronous.\n",
1030                                 tp->width ? "wide " : "");
1031         }
1032 }
1033 EXPORT_SYMBOL(spi_display_xfer_agreement);
1034
1035 #define SETUP_ATTRIBUTE(field)                                          \
1036         i->private_attrs[count] = class_device_attr_##field;            \
1037         if (!i->f->set_##field) {                                       \
1038                 i->private_attrs[count].attr.mode = S_IRUGO;            \
1039                 i->private_attrs[count].store = NULL;                   \
1040         }                                                               \
1041         i->attrs[count] = &i->private_attrs[count];                     \
1042         if (i->f->show_##field)                                         \
1043                 count++
1044
1045 #define SETUP_RELATED_ATTRIBUTE(field, rel_field)                       \
1046         i->private_attrs[count] = class_device_attr_##field;            \
1047         if (!i->f->set_##rel_field) {                                   \
1048                 i->private_attrs[count].attr.mode = S_IRUGO;            \
1049                 i->private_attrs[count].store = NULL;                   \
1050         }                                                               \
1051         i->attrs[count] = &i->private_attrs[count];                     \
1052         if (i->f->show_##rel_field)                                     \
1053                 count++
1054
1055 #define SETUP_HOST_ATTRIBUTE(field)                                     \
1056         i->private_host_attrs[count] = class_device_attr_##field;       \
1057         if (!i->f->set_##field) {                                       \
1058                 i->private_host_attrs[count].attr.mode = S_IRUGO;       \
1059                 i->private_host_attrs[count].store = NULL;              \
1060         }                                                               \
1061         i->host_attrs[count] = &i->private_host_attrs[count];           \
1062         count++
1063
1064 static int spi_device_match(struct attribute_container *cont,
1065                             struct device *dev)
1066 {
1067         struct scsi_device *sdev;
1068         struct Scsi_Host *shost;
1069
1070         if (!scsi_is_sdev_device(dev))
1071                 return 0;
1072
1073         sdev = to_scsi_device(dev);
1074         shost = sdev->host;
1075         if (!shost->transportt  || shost->transportt->host_attrs.ac.class
1076             != &spi_host_class.class)
1077                 return 0;
1078         /* Note: this class has no device attributes, so it has
1079          * no per-HBA allocation and thus we don't need to distinguish
1080          * the attribute containers for the device */
1081         return 1;
1082 }
1083
1084 static int spi_target_match(struct attribute_container *cont,
1085                             struct device *dev)
1086 {
1087         struct Scsi_Host *shost;
1088         struct spi_internal *i;
1089
1090         if (!scsi_is_target_device(dev))
1091                 return 0;
1092
1093         shost = dev_to_shost(dev->parent);
1094         if (!shost->transportt  || shost->transportt->host_attrs.ac.class
1095             != &spi_host_class.class)
1096                 return 0;
1097
1098         i = to_spi_internal(shost->transportt);
1099
1100         return &i->t.target_attrs.ac == cont;
1101 }
1102
1103 static DECLARE_TRANSPORT_CLASS(spi_transport_class,
1104                                "spi_transport",
1105                                spi_setup_transport_attrs,
1106                                NULL,
1107                                NULL);
1108
1109 static DECLARE_ANON_TRANSPORT_CLASS(spi_device_class,
1110                                     spi_device_match,
1111                                     spi_device_configure);
1112
1113 struct scsi_transport_template *
1114 spi_attach_transport(struct spi_function_template *ft)
1115 {
1116         struct spi_internal *i = kmalloc(sizeof(struct spi_internal),
1117                                          GFP_KERNEL);
1118         int count = 0;
1119         if (unlikely(!i))
1120                 return NULL;
1121
1122         memset(i, 0, sizeof(struct spi_internal));
1123
1124
1125         i->t.target_attrs.ac.class = &spi_transport_class.class;
1126         i->t.target_attrs.ac.attrs = &i->attrs[0];
1127         i->t.target_attrs.ac.match = spi_target_match;
1128         transport_container_register(&i->t.target_attrs);
1129         i->t.target_size = sizeof(struct spi_transport_attrs);
1130         i->t.host_attrs.ac.class = &spi_host_class.class;
1131         i->t.host_attrs.ac.attrs = &i->host_attrs[0];
1132         i->t.host_attrs.ac.match = spi_host_match;
1133         transport_container_register(&i->t.host_attrs);
1134         i->t.host_size = sizeof(struct spi_host_attrs);
1135         i->f = ft;
1136
1137         SETUP_ATTRIBUTE(period);
1138         SETUP_RELATED_ATTRIBUTE(min_period, period);
1139         SETUP_ATTRIBUTE(offset);
1140         SETUP_RELATED_ATTRIBUTE(max_offset, offset);
1141         SETUP_ATTRIBUTE(width);
1142         SETUP_RELATED_ATTRIBUTE(max_width, width);
1143         SETUP_ATTRIBUTE(iu);
1144         SETUP_ATTRIBUTE(dt);
1145         SETUP_ATTRIBUTE(qas);
1146         SETUP_ATTRIBUTE(wr_flow);
1147         SETUP_ATTRIBUTE(rd_strm);
1148         SETUP_ATTRIBUTE(rti);
1149         SETUP_ATTRIBUTE(pcomp_en);
1150
1151         /* if you add an attribute but forget to increase SPI_NUM_ATTRS
1152          * this bug will trigger */
1153         BUG_ON(count > SPI_NUM_ATTRS);
1154
1155         i->attrs[count++] = &class_device_attr_revalidate;
1156
1157         i->attrs[count] = NULL;
1158
1159         count = 0;
1160         SETUP_HOST_ATTRIBUTE(signalling);
1161
1162         BUG_ON(count > SPI_HOST_ATTRS);
1163
1164         i->host_attrs[count] = NULL;
1165
1166         return &i->t;
1167 }
1168 EXPORT_SYMBOL(spi_attach_transport);
1169
1170 void spi_release_transport(struct scsi_transport_template *t)
1171 {
1172         struct spi_internal *i = to_spi_internal(t);
1173
1174         transport_container_unregister(&i->t.target_attrs);
1175         transport_container_unregister(&i->t.host_attrs);
1176
1177         kfree(i);
1178 }
1179 EXPORT_SYMBOL(spi_release_transport);
1180
1181 static __init int spi_transport_init(void)
1182 {
1183         int error = transport_class_register(&spi_transport_class);
1184         if (error)
1185                 return error;
1186         error = anon_transport_class_register(&spi_device_class);
1187         return transport_class_register(&spi_host_class);
1188 }
1189
1190 static void __exit spi_transport_exit(void)
1191 {
1192         transport_class_unregister(&spi_transport_class);
1193         anon_transport_class_unregister(&spi_device_class);
1194         transport_class_unregister(&spi_host_class);
1195 }
1196
1197 MODULE_AUTHOR("Martin Hicks");
1198 MODULE_DESCRIPTION("SPI Transport Attributes");
1199 MODULE_LICENSE("GPL");
1200
1201 module_init(spi_transport_init);
1202 module_exit(spi_transport_exit);