drivers/scsi/esp_scsi.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /* esp_scsi.c: ESP SCSI driver.
   3  *
   4  * Copyright (C) 2007 David S. Miller (davem@davemloft.net)
   5  */
   6
   7 #include <linux/kernel.h>
   8 #include <linux/types.h>
   9 #include <linux/slab.h>
  10 #include <linux/delay.h>
  11 #include <linux/list.h>
  12 #include <linux/completion.h>
  13 #include <linux/kallsyms.h>
  14 #include <linux/module.h>
  15 #include <linux/moduleparam.h>
  16 #include <linux/init.h>
  17 #include <linux/irqreturn.h>
  18
  19 #include <asm/irq.h>
  20 #include <asm/io.h>
  21 #include <asm/dma.h>
  22
  23 #include <scsi/scsi.h>
  24 #include <scsi/scsi_host.h>
  25 #include <scsi/scsi_cmnd.h>
  26 #include <scsi/scsi_device.h>
  27 #include <scsi/scsi_tcq.h>
  28 #include <scsi/scsi_dbg.h>
  29 #include <scsi/scsi_transport_spi.h>
  30
  31 #include "esp_scsi.h"
  32
  33 #define DRV_MODULE_NAME         "esp"
  34 #define PFX DRV_MODULE_NAME     ": "
  35 #define DRV_VERSION             "2.000"
  36 #define DRV_MODULE_RELDATE      "April 19, 2007"
  37
  38 /* SCSI bus reset settle time in seconds.  */
  39 static int esp_bus_reset_settle = 3;
  40
  41 static u32 esp_debug;
  42 #define ESP_DEBUG_INTR          0x00000001
  43 #define ESP_DEBUG_SCSICMD       0x00000002
  44 #define ESP_DEBUG_RESET         0x00000004
  45 #define ESP_DEBUG_MSGIN         0x00000008
  46 #define ESP_DEBUG_MSGOUT        0x00000010
  47 #define ESP_DEBUG_CMDDONE       0x00000020
  48 #define ESP_DEBUG_DISCONNECT    0x00000040
  49 #define ESP_DEBUG_DATASTART     0x00000080
  50 #define ESP_DEBUG_DATADONE      0x00000100
  51 #define ESP_DEBUG_RECONNECT     0x00000200
  52 #define ESP_DEBUG_AUTOSENSE     0x00000400
  53 #define ESP_DEBUG_EVENT         0x00000800
  54 #define ESP_DEBUG_COMMAND       0x00001000
  55
  56 #define esp_log_intr(f, a...) \
  57 do {    if (esp_debug & ESP_DEBUG_INTR) \
  58                 shost_printk(KERN_DEBUG, esp->host, f, ## a);   \
  59 } while (0)
  60
  61 #define esp_log_reset(f, a...) \
  62 do {    if (esp_debug & ESP_DEBUG_RESET) \
  63                 shost_printk(KERN_DEBUG, esp->host, f, ## a);   \
  64 } while (0)
  65
  66 #define esp_log_msgin(f, a...) \
  67 do {    if (esp_debug & ESP_DEBUG_MSGIN) \
  68                 shost_printk(KERN_DEBUG, esp->host, f, ## a);   \
  69 } while (0)
  70
  71 #define esp_log_msgout(f, a...) \
  72 do {    if (esp_debug & ESP_DEBUG_MSGOUT) \
  73                 shost_printk(KERN_DEBUG, esp->host, f, ## a);   \
  74 } while (0)
  75
  76 #define esp_log_cmddone(f, a...) \
  77 do {    if (esp_debug & ESP_DEBUG_CMDDONE) \
  78                 shost_printk(KERN_DEBUG, esp->host, f, ## a);   \
  79 } while (0)
  80
  81 #define esp_log_disconnect(f, a...) \
  82 do {    if (esp_debug & ESP_DEBUG_DISCONNECT) \
  83                 shost_printk(KERN_DEBUG, esp->host, f, ## a);   \
  84 } while (0)
  85
  86 #define esp_log_datastart(f, a...) \
  87 do {    if (esp_debug & ESP_DEBUG_DATASTART) \
  88                 shost_printk(KERN_DEBUG, esp->host, f, ## a);   \
  89 } while (0)
  90
  91 #define esp_log_datadone(f, a...) \
  92 do {    if (esp_debug & ESP_DEBUG_DATADONE) \
  93                 shost_printk(KERN_DEBUG, esp->host, f, ## a);   \
  94 } while (0)
  95
  96 #define esp_log_reconnect(f, a...) \
  97 do {    if (esp_debug & ESP_DEBUG_RECONNECT) \
  98                 shost_printk(KERN_DEBUG, esp->host, f, ## a);   \
  99 } while (0)
 100
 101 #define esp_log_autosense(f, a...) \
 102 do {    if (esp_debug & ESP_DEBUG_AUTOSENSE) \
 103                 shost_printk(KERN_DEBUG, esp->host, f, ## a);   \
 104 } while (0)
 105
 106 #define esp_log_event(f, a...) \
 107 do {   if (esp_debug & ESP_DEBUG_EVENT) \
 108                 shost_printk(KERN_DEBUG, esp->host, f, ## a);   \
 109 } while (0)
 110
 111 #define esp_log_command(f, a...) \
 112 do {   if (esp_debug & ESP_DEBUG_COMMAND)       \
 113                 shost_printk(KERN_DEBUG, esp->host, f, ## a);   \
 114 } while (0)
 115
 116 #define esp_read8(REG)          esp->ops->esp_read8(esp, REG)
 117 #define esp_write8(VAL,REG)     esp->ops->esp_write8(esp, VAL, REG)
 118
 119 static void esp_log_fill_regs(struct esp *esp,
 120                               struct esp_event_ent *p)
 121 {
 122         p->sreg = esp->sreg;
 123         p->seqreg = esp->seqreg;
 124         p->sreg2 = esp->sreg2;
 125         p->ireg = esp->ireg;
 126         p->select_state = esp->select_state;
 127         p->event = esp->event;
 128 }
 129
 130 void scsi_esp_cmd(struct esp *esp, u8 val)
 131 {
 132         struct esp_event_ent *p;
 133         int idx = esp->esp_event_cur;
 134
 135         p = &esp->esp_event_log[idx];
 136         p->type = ESP_EVENT_TYPE_CMD;
 137         p->val = val;
 138         esp_log_fill_regs(esp, p);
 139
 140         esp->esp_event_cur = (idx + 1) & (ESP_EVENT_LOG_SZ - 1);
 141
 142         esp_log_command("cmd[%02x]\n", val);
 143         esp_write8(val, ESP_CMD);
 144 }
 145 EXPORT_SYMBOL(scsi_esp_cmd);
 146
 147 static void esp_send_dma_cmd(struct esp *esp, int len, int max_len, int cmd)
 148 {
 149         if (esp->flags & ESP_FLAG_USE_FIFO) {
 150                 int i;
 151
 152                 scsi_esp_cmd(esp, ESP_CMD_FLUSH);
 153                 for (i = 0; i < len; i++)
 154                         esp_write8(esp->command_block[i], ESP_FDATA);
 155                 scsi_esp_cmd(esp, cmd);
 156         } else {
 157                 if (esp->rev == FASHME)
 158                         scsi_esp_cmd(esp, ESP_CMD_FLUSH);
 159                 cmd |= ESP_CMD_DMA;
 160                 esp->ops->send_dma_cmd(esp, esp->command_block_dma,
 161                                        len, max_len, 0, cmd);
 162         }
 163 }
 164
 165 static void esp_event(struct esp *esp, u8 val)
 166 {
 167         struct esp_event_ent *p;
 168         int idx = esp->esp_event_cur;
 169
 170         p = &esp->esp_event_log[idx];
 171         p->type = ESP_EVENT_TYPE_EVENT;
 172         p->val = val;
 173         esp_log_fill_regs(esp, p);
 174
 175         esp->esp_event_cur = (idx + 1) & (ESP_EVENT_LOG_SZ - 1);
 176
 177         esp->event = val;
 178 }
 179
 180 static void esp_dump_cmd_log(struct esp *esp)
 181 {
 182         int idx = esp->esp_event_cur;
 183         int stop = idx;
 184
 185         shost_printk(KERN_INFO, esp->host, "Dumping command log\n");
 186         do {
 187                 struct esp_event_ent *p = &esp->esp_event_log[idx];
 188
 189                 shost_printk(KERN_INFO, esp->host,
 190                              "ent[%d] %s val[%02x] sreg[%02x] seqreg[%02x] "
 191                              "sreg2[%02x] ireg[%02x] ss[%02x] event[%02x]\n",
 192                              idx,
 193                              p->type == ESP_EVENT_TYPE_CMD ? "CMD" : "EVENT",
 194                              p->val, p->sreg, p->seqreg,
 195                              p->sreg2, p->ireg, p->select_state, p->event);
 196
 197                 idx = (idx + 1) & (ESP_EVENT_LOG_SZ - 1);
 198         } while (idx != stop);
 199 }
 200
 201 static void esp_flush_fifo(struct esp *esp)
 202 {
 203         scsi_esp_cmd(esp, ESP_CMD_FLUSH);
 204         if (esp->rev == ESP236) {
 205                 int lim = 1000;
 206
 207                 while (esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES) {
 208                         if (--lim == 0) {
 209                                 shost_printk(KERN_ALERT, esp->host,
 210                                              "ESP_FF_BYTES will not clear!\n");
 211                                 break;
 212                         }
 213                         udelay(1);
 214                 }
 215         }
 216 }
 217
 218 static void hme_read_fifo(struct esp *esp)
 219 {
 220         int fcnt = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;
 221         int idx = 0;
 222
 223         while (fcnt--) {
 224                 esp->fifo[idx++] = esp_read8(ESP_FDATA);
 225                 esp->fifo[idx++] = esp_read8(ESP_FDATA);
 226         }
 227         if (esp->sreg2 & ESP_STAT2_F1BYTE) {
 228                 esp_write8(0, ESP_FDATA);
 229                 esp->fifo[idx++] = esp_read8(ESP_FDATA);
 230                 scsi_esp_cmd(esp, ESP_CMD_FLUSH);
 231         }
 232         esp->fifo_cnt = idx;
 233 }
 234
 235 static void esp_set_all_config3(struct esp *esp, u8 val)
 236 {
 237         int i;
 238
 239         for (i = 0; i < ESP_MAX_TARGET; i++)
 240                 esp->target[i].esp_config3 = val;
 241 }
 242
 243 /* Reset the ESP chip, _not_ the SCSI bus. */
 244 static void esp_reset_esp(struct esp *esp)
 245 {
 246         /* Now reset the ESP chip */
 247         scsi_esp_cmd(esp, ESP_CMD_RC);
 248         scsi_esp_cmd(esp, ESP_CMD_NULL | ESP_CMD_DMA);
 249         if (esp->rev == FAST)
 250                 esp_write8(ESP_CONFIG2_FENAB, ESP_CFG2);
 251         scsi_esp_cmd(esp, ESP_CMD_NULL | ESP_CMD_DMA);
 252
 253         /* This is the only point at which it is reliable to read
 254          * the ID-code for a fast ESP chip variants.
 255          */
 256         esp->max_period = ((35 * esp->ccycle) / 1000);
 257         if (esp->rev == FAST) {
 258                 u8 family_code = ESP_FAMILY(esp_read8(ESP_UID));
 259
 260                 if (family_code == ESP_UID_F236) {
 261                         esp->rev = FAS236;
 262                 } else if (family_code == ESP_UID_HME) {
 263                         esp->rev = FASHME; /* Version is usually '5'. */
 264                 } else if (family_code == ESP_UID_FSC) {
 265                         esp->rev = FSC;
 266                         /* Enable Active Negation */
 267                         esp_write8(ESP_CONFIG4_RADE, ESP_CFG4);
 268                 } else {
 269                         esp->rev = FAS100A;
 270                 }
 271                 esp->min_period = ((4 * esp->ccycle) / 1000);
 272         } else {
 273                 esp->min_period = ((5 * esp->ccycle) / 1000);
 274         }
 275         if (esp->rev == FAS236) {
 276                 /*
 277                  * The AM53c974 chip returns the same ID as FAS236;
 278                  * try to configure glitch eater.
 279                  */
 280                 u8 config4 = ESP_CONFIG4_GE1;
 281                 esp_write8(config4, ESP_CFG4);
 282                 config4 = esp_read8(ESP_CFG4);
 283                 if (config4 & ESP_CONFIG4_GE1) {
 284                         esp->rev = PCSCSI;
 285                         esp_write8(esp->config4, ESP_CFG4);
 286                 }
 287         }
 288         esp->max_period = (esp->max_period + 3)>>2;
 289         esp->min_period = (esp->min_period + 3)>>2;
 290
 291         esp_write8(esp->config1, ESP_CFG1);
 292         switch (esp->rev) {
 293         case ESP100:
 294                 /* nothing to do */
 295                 break;
 296
 297         case ESP100A:
 298                 esp_write8(esp->config2, ESP_CFG2);
 299                 break;
 300
 301         case ESP236:
 302                 /* Slow 236 */
 303                 esp_write8(esp->config2, ESP_CFG2);
 304                 esp->prev_cfg3 = esp->target[0].esp_config3;
 305                 esp_write8(esp->prev_cfg3, ESP_CFG3);
 306                 break;
 307
 308         case FASHME:
 309                 esp->config2 |= (ESP_CONFIG2_HME32 | ESP_CONFIG2_HMEFENAB);
 310                 fallthrough;
 311
 312         case FAS236:
 313         case PCSCSI:
 314         case FSC:
 315                 esp_write8(esp->config2, ESP_CFG2);
 316                 if (esp->rev == FASHME) {
 317                         u8 cfg3 = esp->target[0].esp_config3;
 318
 319                         cfg3 |= ESP_CONFIG3_FCLOCK | ESP_CONFIG3_OBPUSH;
 320                         if (esp->scsi_id >= 8)
 321                                 cfg3 |= ESP_CONFIG3_IDBIT3;
 322                         esp_set_all_config3(esp, cfg3);
 323                 } else {
 324                         u32 cfg3 = esp->target[0].esp_config3;
 325
 326                         cfg3 |= ESP_CONFIG3_FCLK;
 327                         esp_set_all_config3(esp, cfg3);
 328                 }
 329                 esp->prev_cfg3 = esp->target[0].esp_config3;
 330                 esp_write8(esp->prev_cfg3, ESP_CFG3);
 331                 if (esp->rev == FASHME) {
 332                         esp->radelay = 80;
 333                 } else {
 334                         if (esp->flags & ESP_FLAG_DIFFERENTIAL)
 335                                 esp->radelay = 0;
 336                         else
 337                                 esp->radelay = 96;
 338                 }
 339                 break;
 340
 341         case FAS100A:
 342                 /* Fast 100a */
 343                 esp_write8(esp->config2, ESP_CFG2);
 344                 esp_set_all_config3(esp,
 345                                     (esp->target[0].esp_config3 |
 346                                      ESP_CONFIG3_FCLOCK));
 347                 esp->prev_cfg3 = esp->target[0].esp_config3;
 348                 esp_write8(esp->prev_cfg3, ESP_CFG3);
 349                 esp->radelay = 32;
 350                 break;
 351
 352         default:
 353                 break;
 354         }
 355
 356         /* Reload the configuration registers */
 357         esp_write8(esp->cfact, ESP_CFACT);
 358
 359         esp->prev_stp = 0;
 360         esp_write8(esp->prev_stp, ESP_STP);
 361
 362         esp->prev_soff = 0;
 363         esp_write8(esp->prev_soff, ESP_SOFF);
 364
 365         esp_write8(esp->neg_defp, ESP_TIMEO);
 366
 367         /* Eat any bitrot in the chip */
 368         esp_read8(ESP_INTRPT);
 369         udelay(100);
 370 }
 371
 372 static void esp_map_dma(struct esp *esp, struct scsi_cmnd *cmd)
 373 {
 374         struct esp_cmd_priv *spriv = ESP_CMD_PRIV(cmd);
 375         struct scatterlist *sg = scsi_sglist(cmd);
 376         int total = 0, i;
 377         struct scatterlist *s;
 378
 379         if (cmd->sc_data_direction == DMA_NONE)
 380                 return;
 381
 382         if (esp->flags & ESP_FLAG_NO_DMA_MAP) {
 383                 /*
 384                  * For pseudo DMA and PIO we need the virtual address instead of
 385                  * a dma address, so perform an identity mapping.
 386                  */
 387                 spriv->num_sg = scsi_sg_count(cmd);
 388
 389                 scsi_for_each_sg(cmd, s, spriv->num_sg, i) {
 390                         s->dma_address = (uintptr_t)sg_virt(s);
 391                         total += sg_dma_len(s);
 392                 }
 393         } else {
 394                 spriv->num_sg = scsi_dma_map(cmd);
 395                 scsi_for_each_sg(cmd, s, spriv->num_sg, i)
 396                         total += sg_dma_len(s);
 397         }
 398         spriv->cur_residue = sg_dma_len(sg);
 399         spriv->prv_sg = NULL;
 400         spriv->cur_sg = sg;
 401         spriv->tot_residue = total;
 402 }
 403
 404 static dma_addr_t esp_cur_dma_addr(struct esp_cmd_entry *ent,
 405                                    struct scsi_cmnd *cmd)
 406 {
 407         struct esp_cmd_priv *p = ESP_CMD_PRIV(cmd);
 408
 409         if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
 410                 return ent->sense_dma +
 411                         (ent->sense_ptr - cmd->sense_buffer);
 412         }
 413
 414         return sg_dma_address(p->cur_sg) +
 415                 (sg_dma_len(p->cur_sg) -
 416                  p->cur_residue);
 417 }
 418
 419 static unsigned int esp_cur_dma_len(struct esp_cmd_entry *ent,
 420                                     struct scsi_cmnd *cmd)
 421 {
 422         struct esp_cmd_priv *p = ESP_CMD_PRIV(cmd);
 423
 424         if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
 425                 return SCSI_SENSE_BUFFERSIZE -
 426                         (ent->sense_ptr - cmd->sense_buffer);
 427         }
 428         return p->cur_residue;
 429 }
 430
 431 static void esp_advance_dma(struct esp *esp, struct esp_cmd_entry *ent,
 432                             struct scsi_cmnd *cmd, unsigned int len)
 433 {
 434         struct esp_cmd_priv *p = ESP_CMD_PRIV(cmd);
 435
 436         if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
 437                 ent->sense_ptr += len;
 438                 return;
 439         }
 440
 441         p->cur_residue -= len;
 442         p->tot_residue -= len;
 443         if (p->cur_residue < 0 || p->tot_residue < 0) {
 444                 shost_printk(KERN_ERR, esp->host,
 445                              "Data transfer overflow.\n");
 446                 shost_printk(KERN_ERR, esp->host,
 447                              "cur_residue[%d] tot_residue[%d] len[%u]\n",
 448                              p->cur_residue, p->tot_residue, len);
 449                 p->cur_residue = 0;
 450                 p->tot_residue = 0;
 451         }
 452         if (!p->cur_residue && p->tot_residue) {
 453                 p->prv_sg = p->cur_sg;
 454                 p->cur_sg = sg_next(p->cur_sg);
 455                 p->cur_residue = sg_dma_len(p->cur_sg);
 456         }
 457 }
 458
 459 static void esp_unmap_dma(struct esp *esp, struct scsi_cmnd *cmd)
 460 {
 461         if (!(esp->flags & ESP_FLAG_NO_DMA_MAP))
 462                 scsi_dma_unmap(cmd);
 463 }
 464
 465 static void esp_save_pointers(struct esp *esp, struct esp_cmd_entry *ent)
 466 {
 467         struct scsi_cmnd *cmd = ent->cmd;
 468         struct esp_cmd_priv *spriv = ESP_CMD_PRIV(cmd);
 469
 470         if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
 471                 ent->saved_sense_ptr = ent->sense_ptr;
 472                 return;
 473         }
 474         ent->saved_cur_residue = spriv->cur_residue;
 475         ent->saved_prv_sg = spriv->prv_sg;
 476         ent->saved_cur_sg = spriv->cur_sg;
 477         ent->saved_tot_residue = spriv->tot_residue;
 478 }
 479
 480 static void esp_restore_pointers(struct esp *esp, struct esp_cmd_entry *ent)
 481 {
 482         struct scsi_cmnd *cmd = ent->cmd;
 483         struct esp_cmd_priv *spriv = ESP_CMD_PRIV(cmd);
 484
 485         if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
 486                 ent->sense_ptr = ent->saved_sense_ptr;
 487                 return;
 488         }
 489         spriv->cur_residue = ent->saved_cur_residue;
 490         spriv->prv_sg = ent->saved_prv_sg;
 491         spriv->cur_sg = ent->saved_cur_sg;
 492         spriv->tot_residue = ent->saved_tot_residue;
 493 }
 494
 495 static void esp_write_tgt_config3(struct esp *esp, int tgt)
 496 {
 497         if (esp->rev > ESP100A) {
 498                 u8 val = esp->target[tgt].esp_config3;
 499
 500                 if (val != esp->prev_cfg3) {
 501                         esp->prev_cfg3 = val;
 502                         esp_write8(val, ESP_CFG3);
 503                 }
 504         }
 505 }
 506
 507 static void esp_write_tgt_sync(struct esp *esp, int tgt)
 508 {
 509         u8 off = esp->target[tgt].esp_offset;
 510         u8 per = esp->target[tgt].esp_period;
 511
 512         if (off != esp->prev_soff) {
 513                 esp->prev_soff = off;
 514                 esp_write8(off, ESP_SOFF);
 515         }
 516         if (per != esp->prev_stp) {
 517                 esp->prev_stp = per;
 518                 esp_write8(per, ESP_STP);
 519         }
 520 }
 521
 522 static u32 esp_dma_length_limit(struct esp *esp, u32 dma_addr, u32 dma_len)
 523 {
 524         if (esp->rev == FASHME) {
 525                 /* Arbitrary segment boundaries, 24-bit counts.  */
 526                 if (dma_len > (1U << 24))
 527                         dma_len = (1U << 24);
 528         } else {
 529                 u32 base, end;
 530
 531                 /* ESP chip limits other variants by 16-bits of transfer
 532                  * count.  Actually on FAS100A and FAS236 we could get
 533                  * 24-bits of transfer count by enabling ESP_CONFIG2_FENAB
 534                  * in the ESP_CFG2 register but that causes other unwanted
 535                  * changes so we don't use it currently.
 536                  */
 537                 if (dma_len > (1U << 16))
 538                         dma_len = (1U << 16);
 539
 540                 /* All of the DMA variants hooked up to these chips
 541                  * cannot handle crossing a 24-bit address boundary.
 542                  */
 543                 base = dma_addr & ((1U << 24) - 1U);
 544                 end = base + dma_len;
 545                 if (end > (1U << 24))
 546                         end = (1U <<24);
 547                 dma_len = end - base;
 548         }
 549         return dma_len;
 550 }
 551
 552 static int esp_need_to_nego_wide(struct esp_target_data *tp)
 553 {
 554         struct scsi_target *target = tp->starget;
 555
 556         return spi_width(target) != tp->nego_goal_width;
 557 }
 558
 559 static int esp_need_to_nego_sync(struct esp_target_data *tp)
 560 {
 561         struct scsi_target *target = tp->starget;
 562
 563         /* When offset is zero, period is "don't care".  */
 564         if (!spi_offset(target) && !tp->nego_goal_offset)
 565                 return 0;
 566
 567         if (spi_offset(target) == tp->nego_goal_offset &&
 568             spi_period(target) == tp->nego_goal_period)
 569                 return 0;
 570
 571         return 1;
 572 }
 573
 574 static int esp_alloc_lun_tag(struct esp_cmd_entry *ent,
 575                              struct esp_lun_data *lp)
 576 {
 577         if (!ent->orig_tag[0]) {
 578                 /* Non-tagged, slot already taken?  */
 579                 if (lp->non_tagged_cmd)
 580                         return -EBUSY;
 581
 582                 if (lp->hold) {
 583                         /* We are being held by active tagged
 584                          * commands.
 585                          */
 586                         if (lp->num_tagged)
 587                                 return -EBUSY;
 588
 589                         /* Tagged commands completed, we can unplug
 590                          * the queue and run this untagged command.
 591                          */
 592                         lp->hold = 0;
 593                 } else if (lp->num_tagged) {
 594                         /* Plug the queue until num_tagged decreases
 595                          * to zero in esp_free_lun_tag.
 596                          */
 597                         lp->hold = 1;
 598                         return -EBUSY;
 599                 }
 600
 601                 lp->non_tagged_cmd = ent;
 602                 return 0;
 603         }
 604
 605         /* Tagged command. Check that it isn't blocked by a non-tagged one. */
 606         if (lp->non_tagged_cmd || lp->hold)
 607                 return -EBUSY;
 608
 609         BUG_ON(lp->tagged_cmds[ent->orig_tag[1]]);
 610
 611         lp->tagged_cmds[ent->orig_tag[1]] = ent;
 612         lp->num_tagged++;
 613
 614         return 0;
 615 }
 616
 617 static void esp_free_lun_tag(struct esp_cmd_entry *ent,
 618                              struct esp_lun_data *lp)
 619 {
 620         if (ent->orig_tag[0]) {
 621                 BUG_ON(lp->tagged_cmds[ent->orig_tag[1]] != ent);
 622                 lp->tagged_cmds[ent->orig_tag[1]] = NULL;
 623                 lp->num_tagged--;
 624         } else {
 625                 BUG_ON(lp->non_tagged_cmd != ent);
 626                 lp->non_tagged_cmd = NULL;
 627         }
 628 }
 629
 630 static void esp_map_sense(struct esp *esp, struct esp_cmd_entry *ent)
 631 {
 632         ent->sense_ptr = ent->cmd->sense_buffer;
 633         if (esp->flags & ESP_FLAG_NO_DMA_MAP) {
 634                 ent->sense_dma = (uintptr_t)ent->sense_ptr;
 635                 return;
 636         }
 637
 638         ent->sense_dma = dma_map_single(esp->dev, ent->sense_ptr,
 639                                         SCSI_SENSE_BUFFERSIZE, DMA_FROM_DEVICE);
 640 }
 641
 642 static void esp_unmap_sense(struct esp *esp, struct esp_cmd_entry *ent)
 643 {
 644         if (!(esp->flags & ESP_FLAG_NO_DMA_MAP))
 645                 dma_unmap_single(esp->dev, ent->sense_dma,
 646                                  SCSI_SENSE_BUFFERSIZE, DMA_FROM_DEVICE);
 647         ent->sense_ptr = NULL;
 648 }
 649
 650 /* When a contingent allegiance conditon is created, we force feed a
 651  * REQUEST_SENSE command to the device to fetch the sense data.  I
 652  * tried many other schemes, relying on the scsi error handling layer
 653  * to send out the REQUEST_SENSE automatically, but this was difficult
 654  * to get right especially in the presence of applications like smartd
 655  * which use SG_IO to send out their own REQUEST_SENSE commands.
 656  */
 657 static void esp_autosense(struct esp *esp, struct esp_cmd_entry *ent)
 658 {
 659         struct scsi_cmnd *cmd = ent->cmd;
 660         struct scsi_device *dev = cmd->device;
 661         int tgt, lun;
 662         u8 *p, val;
 663
 664         tgt = dev->id;
 665         lun = dev->lun;
 666
 667
 668         if (!ent->sense_ptr) {
 669                 esp_log_autosense("Doing auto-sense for tgt[%d] lun[%d]\n",
 670                                   tgt, lun);
 671                 esp_map_sense(esp, ent);
 672         }
 673         ent->saved_sense_ptr = ent->sense_ptr;
 674
 675         esp->active_cmd = ent;
 676
 677         p = esp->command_block;
 678         esp->msg_out_len = 0;
 679
 680         *p++ = IDENTIFY(0, lun);
 681         *p++ = REQUEST_SENSE;
 682         *p++ = ((dev->scsi_level <= SCSI_2) ?
 683                 (lun << 5) : 0);
 684         *p++ = 0;
 685         *p++ = 0;
 686         *p++ = SCSI_SENSE_BUFFERSIZE;
 687         *p++ = 0;
 688
 689         esp->select_state = ESP_SELECT_BASIC;
 690
 691         val = tgt;
 692         if (esp->rev == FASHME)
 693                 val |= ESP_BUSID_RESELID | ESP_BUSID_CTR32BIT;
 694         esp_write8(val, ESP_BUSID);
 695
 696         esp_write_tgt_sync(esp, tgt);
 697         esp_write_tgt_config3(esp, tgt);
 698
 699         val = (p - esp->command_block);
 700
 701         esp_send_dma_cmd(esp, val, 16, ESP_CMD_SELA);
 702 }
 703
 704 static struct esp_cmd_entry *find_and_prep_issuable_command(struct esp *esp)
 705 {
 706         struct esp_cmd_entry *ent;
 707
 708         list_for_each_entry(ent, &esp->queued_cmds, list) {
 709                 struct scsi_cmnd *cmd = ent->cmd;
 710                 struct scsi_device *dev = cmd->device;
 711                 struct esp_lun_data *lp = dev->hostdata;
 712
 713                 if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
 714                         ent->tag[0] = 0;
 715                         ent->tag[1] = 0;
 716                         return ent;
 717                 }
 718
 719                 if (!spi_populate_tag_msg(&ent->tag[0], cmd)) {
 720                         ent->tag[0] = 0;
 721                         ent->tag[1] = 0;
 722                 }
 723                 ent->orig_tag[0] = ent->tag[0];
 724                 ent->orig_tag[1] = ent->tag[1];
 725
 726                 if (esp_alloc_lun_tag(ent, lp) < 0)
 727                         continue;
 728
 729                 return ent;
 730         }
 731
 732         return NULL;
 733 }
 734
 735 static void esp_maybe_execute_command(struct esp *esp)
 736 {
 737         struct esp_target_data *tp;
 738         struct scsi_device *dev;
 739         struct scsi_cmnd *cmd;
 740         struct esp_cmd_entry *ent;
 741         bool select_and_stop = false;
 742         int tgt, lun, i;
 743         u32 val, start_cmd;
 744         u8 *p;
 745
 746         if (esp->active_cmd ||
 747             (esp->flags & ESP_FLAG_RESETTING))
 748                 return;
 749
 750         ent = find_and_prep_issuable_command(esp);
 751         if (!ent)
 752                 return;
 753
 754         if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
 755                 esp_autosense(esp, ent);
 756                 return;
 757         }
 758
 759         cmd = ent->cmd;
 760         dev = cmd->device;
 761         tgt = dev->id;
 762         lun = dev->lun;
 763         tp = &esp->target[tgt];
 764
 765         list_move(&ent->list, &esp->active_cmds);
 766
 767         esp->active_cmd = ent;
 768
 769         esp_map_dma(esp, cmd);
 770         esp_save_pointers(esp, ent);
 771
 772         if (!(cmd->cmd_len == 6 || cmd->cmd_len == 10 || cmd->cmd_len == 12))
 773                 select_and_stop = true;
 774
 775         p = esp->command_block;
 776
 777         esp->msg_out_len = 0;
 778         if (tp->flags & ESP_TGT_CHECK_NEGO) {
 779                 /* Need to negotiate.  If the target is broken
 780                  * go for synchronous transfers and non-wide.
 781                  */
 782                 if (tp->flags & ESP_TGT_BROKEN) {
 783                         tp->flags &= ~ESP_TGT_DISCONNECT;
 784                         tp->nego_goal_period = 0;
 785                         tp->nego_goal_offset = 0;
 786                         tp->nego_goal_width = 0;
 787                         tp->nego_goal_tags = 0;
 788                 }
 789
 790                 /* If the settings are not changing, skip this.  */
 791                 if (spi_width(tp->starget) == tp->nego_goal_width &&
 792                     spi_period(tp->starget) == tp->nego_goal_period &&
 793                     spi_offset(tp->starget) == tp->nego_goal_offset) {
 794                         tp->flags &= ~ESP_TGT_CHECK_NEGO;
 795                         goto build_identify;
 796                 }
 797
 798                 if (esp->rev == FASHME && esp_need_to_nego_wide(tp)) {
 799                         esp->msg_out_len =
 800                                 spi_populate_width_msg(&esp->msg_out[0],
 801                                                        (tp->nego_goal_width ?
 802                                                         1 : 0));
 803                         tp->flags |= ESP_TGT_NEGO_WIDE;
 804                 } else if (esp_need_to_nego_sync(tp)) {
 805                         esp->msg_out_len =
 806                                 spi_populate_sync_msg(&esp->msg_out[0],
 807                                                       tp->nego_goal_period,
 808                                                       tp->nego_goal_offset);
 809                         tp->flags |= ESP_TGT_NEGO_SYNC;
 810                 } else {
 811                         tp->flags &= ~ESP_TGT_CHECK_NEGO;
 812                 }
 813
 814                 /* If there are multiple message bytes, use Select and Stop */
 815                 if (esp->msg_out_len)
 816                         select_and_stop = true;
 817         }
 818
 819 build_identify:
 820         *p++ = IDENTIFY(tp->flags & ESP_TGT_DISCONNECT, lun);
 821
 822         if (ent->tag[0] && esp->rev == ESP100) {
 823                 /* ESP100 lacks select w/atn3 command, use select
 824                  * and stop instead.
 825                  */
 826                 select_and_stop = true;
 827         }
 828
 829         if (select_and_stop) {
 830                 esp->cmd_bytes_left = cmd->cmd_len;
 831                 esp->cmd_bytes_ptr = &cmd->cmnd[0];
 832
 833                 if (ent->tag[0]) {
 834                         for (i = esp->msg_out_len - 1;
 835                              i >= 0; i--)
 836                                 esp->msg_out[i + 2] = esp->msg_out[i];
 837                         esp->msg_out[0] = ent->tag[0];
 838                         esp->msg_out[1] = ent->tag[1];
 839                         esp->msg_out_len += 2;
 840                 }
 841
 842                 start_cmd = ESP_CMD_SELAS;
 843                 esp->select_state = ESP_SELECT_MSGOUT;
 844         } else {
 845                 start_cmd = ESP_CMD_SELA;
 846                 if (ent->tag[0]) {
 847                         *p++ = ent->tag[0];
 848                         *p++ = ent->tag[1];
 849
 850                         start_cmd = ESP_CMD_SA3;
 851                 }
 852
 853                 for (i = 0; i < cmd->cmd_len; i++)
 854                         *p++ = cmd->cmnd[i];
 855
 856                 esp->select_state = ESP_SELECT_BASIC;
 857         }
 858         val = tgt;
 859         if (esp->rev == FASHME)
 860                 val |= ESP_BUSID_RESELID | ESP_BUSID_CTR32BIT;
 861         esp_write8(val, ESP_BUSID);
 862
 863         esp_write_tgt_sync(esp, tgt);
 864         esp_write_tgt_config3(esp, tgt);
 865
 866         val = (p - esp->command_block);
 867
 868         if (esp_debug & ESP_DEBUG_SCSICMD) {
 869                 printk("ESP: tgt[%d] lun[%d] scsi_cmd [ ", tgt, lun);
 870                 for (i = 0; i < cmd->cmd_len; i++)
 871                         printk("%02x ", cmd->cmnd[i]);
 872                 printk("]\n");
 873         }
 874
 875         esp_send_dma_cmd(esp, val, 16, start_cmd);
 876 }
 877
 878 static struct esp_cmd_entry *esp_get_ent(struct esp *esp)
 879 {
 880         struct list_head *head = &esp->esp_cmd_pool;
 881         struct esp_cmd_entry *ret;
 882
 883         if (list_empty(head)) {
 884                 ret = kzalloc(sizeof(struct esp_cmd_entry), GFP_ATOMIC);
 885         } else {
 886                 ret = list_entry(head->next, struct esp_cmd_entry, list);
 887                 list_del(&ret->list);
 888                 memset(ret, 0, sizeof(*ret));
 889         }
 890         return ret;
 891 }
 892
 893 static void esp_put_ent(struct esp *esp, struct esp_cmd_entry *ent)
 894 {
 895         list_add(&ent->list, &esp->esp_cmd_pool);
 896 }
 897
 898 static void esp_cmd_is_done(struct esp *esp, struct esp_cmd_entry *ent,
 899                             struct scsi_cmnd *cmd, unsigned int result)
 900 {
 901         struct scsi_device *dev = cmd->device;
 902         int tgt = dev->id;
 903         int lun = dev->lun;
 904
 905         esp->active_cmd = NULL;
 906         esp_unmap_dma(esp, cmd);
 907         esp_free_lun_tag(ent, dev->hostdata);
 908         cmd->result = result;
 909
 910         if (ent->eh_done) {
 911                 complete(ent->eh_done);
 912                 ent->eh_done = NULL;
 913         }
 914
 915         if (ent->flags & ESP_CMD_FLAG_AUTOSENSE) {
 916                 esp_unmap_sense(esp, ent);
 917
 918                 /* Restore the message/status bytes to what we actually
 919                  * saw originally.  Also, report that we are providing
 920                  * the sense data.
 921                  */
 922                 cmd->result = ((DRIVER_SENSE << 24) |
 923                                (DID_OK << 16) |
 924                                (COMMAND_COMPLETE << 8) |
 925                                (SAM_STAT_CHECK_CONDITION << 0));
 926
 927                 ent->flags &= ~ESP_CMD_FLAG_AUTOSENSE;
 928                 if (esp_debug & ESP_DEBUG_AUTOSENSE) {
 929                         int i;
 930
 931                         printk("esp%d: tgt[%d] lun[%d] AUTO SENSE[ ",
 932                                esp->host->unique_id, tgt, lun);
 933                         for (i = 0; i < 18; i++)
 934                                 printk("%02x ", cmd->sense_buffer[i]);
 935                         printk("]\n");
 936                 }
 937         }
 938
 939         cmd->scsi_done(cmd);
 940
 941         list_del(&ent->list);
 942         esp_put_ent(esp, ent);
 943
 944         esp_maybe_execute_command(esp);
 945 }
 946
 947 static unsigned int compose_result(unsigned int status, unsigned int message,
 948                                    unsigned int driver_code)
 949 {
 950         return (status | (message << 8) | (driver_code << 16));
 951 }
 952
 953 static void esp_event_queue_full(struct esp *esp, struct esp_cmd_entry *ent)
 954 {
 955         struct scsi_device *dev = ent->cmd->device;
 956         struct esp_lun_data *lp = dev->hostdata;
 957
 958         scsi_track_queue_full(dev, lp->num_tagged - 1);
 959 }
 960
 961 static int esp_queuecommand_lck(struct scsi_cmnd *cmd, void (*done)(struct scsi_cmnd *))
 962 {
 963         struct scsi_device *dev = cmd->device;
 964         struct esp *esp = shost_priv(dev->host);
 965         struct esp_cmd_priv *spriv;
 966         struct esp_cmd_entry *ent;
 967
 968         ent = esp_get_ent(esp);
 969         if (!ent)
 970                 return SCSI_MLQUEUE_HOST_BUSY;
 971
 972         ent->cmd = cmd;
 973
 974         cmd->scsi_done = done;
 975
 976         spriv = ESP_CMD_PRIV(cmd);
 977         spriv->num_sg = 0;
 978
 979         list_add_tail(&ent->list, &esp->queued_cmds);
 980
 981         esp_maybe_execute_command(esp);
 982
 983         return 0;
 984 }
 985
 986 static DEF_SCSI_QCMD(esp_queuecommand)
 987
 988 static int esp_check_gross_error(struct esp *esp)
 989 {
 990         if (esp->sreg & ESP_STAT_SPAM) {
 991                 /* Gross Error, could be one of:
 992                  * - top of fifo overwritten
 993                  * - top of command register overwritten
 994                  * - DMA programmed with wrong direction
 995                  * - improper phase change
 996                  */
 997                 shost_printk(KERN_ERR, esp->host,
 998                              "Gross error sreg[%02x]\n", esp->sreg);
 999                 /* XXX Reset the chip. XXX */
1000                 return 1;
1001         }
1002         return 0;
1003 }
1004
1005 static int esp_check_spur_intr(struct esp *esp)
1006 {
1007         switch (esp->rev) {
1008         case ESP100:
1009         case ESP100A:
1010                 /* The interrupt pending bit of the status register cannot
1011                  * be trusted on these revisions.
1012                  */
1013                 esp->sreg &= ~ESP_STAT_INTR;
1014                 break;
1015
1016         default:
1017                 if (!(esp->sreg & ESP_STAT_INTR)) {
1018                         if (esp->ireg & ESP_INTR_SR)
1019                                 return 1;
1020
1021                         /* If the DMA is indicating interrupt pending and the
1022                          * ESP is not, the only possibility is a DMA error.
1023                          */
1024                         if (!esp->ops->dma_error(esp)) {
1025                                 shost_printk(KERN_ERR, esp->host,
1026                                              "Spurious irq, sreg=%02x.\n",
1027                                              esp->sreg);
1028                                 return -1;
1029                         }
1030
1031                         shost_printk(KERN_ERR, esp->host, "DMA error\n");
1032
1033                         /* XXX Reset the chip. XXX */
1034                         return -1;
1035                 }
1036                 break;
1037         }
1038
1039         return 0;
1040 }
1041
1042 static void esp_schedule_reset(struct esp *esp)
1043 {
1044         esp_log_reset("esp_schedule_reset() from %ps\n",
1045                       __builtin_return_address(0));
1046         esp->flags |= ESP_FLAG_RESETTING;
1047         esp_event(esp, ESP_EVENT_RESET);
1048 }
1049
1050 /* In order to avoid having to add a special half-reconnected state
1051  * into the driver we just sit here and poll through the rest of
1052  * the reselection process to get the tag message bytes.
1053  */
1054 static struct esp_cmd_entry *esp_reconnect_with_tag(struct esp *esp,
1055                                                     struct esp_lun_data *lp)
1056 {
1057         struct esp_cmd_entry *ent;
1058         int i;
1059
1060         if (!lp->num_tagged) {
1061                 shost_printk(KERN_ERR, esp->host,
1062                              "Reconnect w/num_tagged==0\n");
1063                 return NULL;
1064         }
1065
1066         esp_log_reconnect("reconnect tag, ");
1067
1068         for (i = 0; i < ESP_QUICKIRQ_LIMIT; i++) {
1069                 if (esp->ops->irq_pending(esp))
1070                         break;
1071         }
1072         if (i == ESP_QUICKIRQ_LIMIT) {
1073                 shost_printk(KERN_ERR, esp->host,
1074                              "Reconnect IRQ1 timeout\n");
1075                 return NULL;
1076         }
1077
1078         esp->sreg = esp_read8(ESP_STATUS);
1079         esp->ireg = esp_read8(ESP_INTRPT);
1080
1081         esp_log_reconnect("IRQ(%d:%x:%x), ",
1082                           i, esp->ireg, esp->sreg);
1083
1084         if (esp->ireg & ESP_INTR_DC) {
1085                 shost_printk(KERN_ERR, esp->host,
1086                              "Reconnect, got disconnect.\n");
1087                 return NULL;
1088         }
1089
1090         if ((esp->sreg & ESP_STAT_PMASK) != ESP_MIP) {
1091                 shost_printk(KERN_ERR, esp->host,
1092                              "Reconnect, not MIP sreg[%02x].\n", esp->sreg);
1093                 return NULL;
1094         }
1095
1096         /* DMA in the tag bytes... */
1097         esp->command_block[0] = 0xff;
1098         esp->command_block[1] = 0xff;
1099         esp->ops->send_dma_cmd(esp, esp->command_block_dma,
1100                                2, 2, 1, ESP_CMD_DMA | ESP_CMD_TI);
1101
1102         /* ACK the message.  */
1103         scsi_esp_cmd(esp, ESP_CMD_MOK);
1104
1105         for (i = 0; i < ESP_RESELECT_TAG_LIMIT; i++) {
1106                 if (esp->ops->irq_pending(esp)) {
1107                         esp->sreg = esp_read8(ESP_STATUS);
1108                         esp->ireg = esp_read8(ESP_INTRPT);
1109                         if (esp->ireg & ESP_INTR_FDONE)
1110                                 break;
1111                 }
1112                 udelay(1);
1113         }
1114         if (i == ESP_RESELECT_TAG_LIMIT) {
1115                 shost_printk(KERN_ERR, esp->host, "Reconnect IRQ2 timeout\n");
1116                 return NULL;
1117         }
1118         esp->ops->dma_drain(esp);
1119         esp->ops->dma_invalidate(esp);
1120
1121         esp_log_reconnect("IRQ2(%d:%x:%x) tag[%x:%x]\n",
1122                           i, esp->ireg, esp->sreg,
1123                           esp->command_block[0],
1124                           esp->command_block[1]);
1125
1126         if (esp->command_block[0] < SIMPLE_QUEUE_TAG ||
1127             esp->command_block[0] > ORDERED_QUEUE_TAG) {
1128                 shost_printk(KERN_ERR, esp->host,
1129                              "Reconnect, bad tag type %02x.\n",
1130                              esp->command_block[0]);
1131                 return NULL;
1132         }
1133
1134         ent = lp->tagged_cmds[esp->command_block[1]];
1135         if (!ent) {
1136                 shost_printk(KERN_ERR, esp->host,
1137                              "Reconnect, no entry for tag %02x.\n",
1138                              esp->command_block[1]);
1139                 return NULL;
1140         }
1141
1142         return ent;
1143 }
1144
1145 static int esp_reconnect(struct esp *esp)
1146 {
1147         struct esp_cmd_entry *ent;
1148         struct esp_target_data *tp;
1149         struct esp_lun_data *lp;
1150         struct scsi_device *dev;
1151         int target, lun;
1152
1153         BUG_ON(esp->active_cmd);
1154         if (esp->rev == FASHME) {
1155                 /* FASHME puts the target and lun numbers directly
1156                  * into the fifo.
1157                  */
1158                 target = esp->fifo[0];
1159                 lun = esp->fifo[1] & 0x7;
1160         } else {
1161                 u8 bits = esp_read8(ESP_FDATA);
1162
1163                 /* Older chips put the lun directly into the fifo, but
1164                  * the target is given as a sample of the arbitration
1165                  * lines on the bus at reselection time.  So we should
1166                  * see the ID of the ESP and the one reconnecting target
1167                  * set in the bitmap.
1168                  */
1169                 if (!(bits & esp->scsi_id_mask))
1170                         goto do_reset;
1171                 bits &= ~esp->scsi_id_mask;
1172                 if (!bits || (bits & (bits - 1)))
1173                         goto do_reset;
1174
1175                 target = ffs(bits) - 1;
1176                 lun = (esp_read8(ESP_FDATA) & 0x7);
1177
1178                 scsi_esp_cmd(esp, ESP_CMD_FLUSH);
1179                 if (esp->rev == ESP100) {
1180                         u8 ireg = esp_read8(ESP_INTRPT);
1181                         /* This chip has a bug during reselection that can
1182                          * cause a spurious illegal-command interrupt, which
1183                          * we simply ACK here.  Another possibility is a bus
1184                          * reset so we must check for that.
1185                          */
1186                         if (ireg & ESP_INTR_SR)
1187                                 goto do_reset;
1188                 }
1189                 scsi_esp_cmd(esp, ESP_CMD_NULL);
1190         }
1191
1192         esp_write_tgt_sync(esp, target);
1193         esp_write_tgt_config3(esp, target);
1194
1195         scsi_esp_cmd(esp, ESP_CMD_MOK);
1196
1197         if (esp->rev == FASHME)
1198                 esp_write8(target | ESP_BUSID_RESELID | ESP_BUSID_CTR32BIT,
1199                            ESP_BUSID);
1200
1201         tp = &esp->target[target];
1202         dev = __scsi_device_lookup_by_target(tp->starget, lun);
1203         if (!dev) {
1204                 shost_printk(KERN_ERR, esp->host,
1205                              "Reconnect, no lp tgt[%u] lun[%u]\n",
1206                              target, lun);
1207                 goto do_reset;
1208         }
1209         lp = dev->hostdata;
1210
1211         ent = lp->non_tagged_cmd;
1212         if (!ent) {
1213                 ent = esp_reconnect_with_tag(esp, lp);
1214                 if (!ent)
1215                         goto do_reset;
1216         }
1217
1218         esp->active_cmd = ent;
1219
1220         esp_event(esp, ESP_EVENT_CHECK_PHASE);
1221         esp_restore_pointers(esp, ent);
1222         esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
1223         return 1;
1224
1225 do_reset:
1226         esp_schedule_reset(esp);
1227         return 0;
1228 }
1229
1230 static int esp_finish_select(struct esp *esp)
1231 {
1232         struct esp_cmd_entry *ent;
1233         struct scsi_cmnd *cmd;
1234
1235         /* No longer selecting.  */
1236         esp->select_state = ESP_SELECT_NONE;
1237
1238         esp->seqreg = esp_read8(ESP_SSTEP) & ESP_STEP_VBITS;
1239         ent = esp->active_cmd;
1240         cmd = ent->cmd;
1241
1242         if (esp->ops->dma_error(esp)) {
1243                 /* If we see a DMA error during or as a result of selection,
1244                  * all bets are off.
1245                  */
1246                 esp_schedule_reset(esp);
1247                 esp_cmd_is_done(esp, ent, cmd, (DID_ERROR << 16));
1248                 return 0;
1249         }
1250
1251         esp->ops->dma_invalidate(esp);
1252
1253         if (esp->ireg == (ESP_INTR_RSEL | ESP_INTR_FDONE)) {
1254                 struct esp_target_data *tp = &esp->target[cmd->device->id];
1255
1256                 /* Carefully back out of the selection attempt.  Release
1257                  * resources (such as DMA mapping & TAG) and reset state (such
1258                  * as message out and command delivery variables).
1259                  */
1260                 if (!(ent->flags & ESP_CMD_FLAG_AUTOSENSE)) {
1261                         esp_unmap_dma(esp, cmd);
1262                         esp_free_lun_tag(ent, cmd->device->hostdata);
1263                         tp->flags &= ~(ESP_TGT_NEGO_SYNC | ESP_TGT_NEGO_WIDE);
1264                         esp->cmd_bytes_ptr = NULL;
1265                         esp->cmd_bytes_left = 0;
1266                 } else {
1267                         esp_unmap_sense(esp, ent);
1268                 }
1269
1270                 /* Now that the state is unwound properly, put back onto
1271                  * the issue queue.  This command is no longer active.
1272                  */
1273                 list_move(&ent->list, &esp->queued_cmds);
1274                 esp->active_cmd = NULL;
1275
1276                 /* Return value ignored by caller, it directly invokes
1277                  * esp_reconnect().
1278                  */
1279                 return 0;
1280         }
1281
1282         if (esp->ireg == ESP_INTR_DC) {
1283                 struct scsi_device *dev = cmd->device;
1284
1285                 /* Disconnect.  Make sure we re-negotiate sync and
1286                  * wide parameters if this target starts responding
1287                  * again in the future.
1288                  */
1289                 esp->target[dev->id].flags |= ESP_TGT_CHECK_NEGO;
1290
1291                 scsi_esp_cmd(esp, ESP_CMD_ESEL);
1292                 esp_cmd_is_done(esp, ent, cmd, (DID_BAD_TARGET << 16));
1293                 return 1;
1294         }
1295
1296         if (esp->ireg == (ESP_INTR_FDONE | ESP_INTR_BSERV)) {
1297                 /* Selection successful.  On pre-FAST chips we have
1298                  * to do a NOP and possibly clean out the FIFO.
1299                  */
1300                 if (esp->rev <= ESP236) {
1301                         int fcnt = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;
1302
1303                         scsi_esp_cmd(esp, ESP_CMD_NULL);
1304
1305                         if (!fcnt &&
1306                             (!esp->prev_soff ||
1307                              ((esp->sreg & ESP_STAT_PMASK) != ESP_DIP)))
1308                                 esp_flush_fifo(esp);
1309                 }
1310
1311                 /* If we are doing a Select And Stop command, negotiation, etc.
1312                  * we'll do the right thing as we transition to the next phase.
1313                  */
1314                 esp_event(esp, ESP_EVENT_CHECK_PHASE);
1315                 return 0;
1316         }
1317
1318         shost_printk(KERN_INFO, esp->host,
1319                      "Unexpected selection completion ireg[%x]\n", esp->ireg);
1320         esp_schedule_reset(esp);
1321         return 0;
1322 }
1323
1324 static int esp_data_bytes_sent(struct esp *esp, struct esp_cmd_entry *ent,
1325                                struct scsi_cmnd *cmd)
1326 {
1327         int fifo_cnt, ecount, bytes_sent, flush_fifo;
1328
1329         fifo_cnt = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;
1330         if (esp->prev_cfg3 & ESP_CONFIG3_EWIDE)
1331                 fifo_cnt <<= 1;
1332
1333         ecount = 0;
1334         if (!(esp->sreg & ESP_STAT_TCNT)) {
1335                 ecount = ((unsigned int)esp_read8(ESP_TCLOW) |
1336                           (((unsigned int)esp_read8(ESP_TCMED)) << 8));
1337                 if (esp->rev == FASHME)
1338                         ecount |= ((unsigned int)esp_read8(FAS_RLO)) << 16;
1339                 if (esp->rev == PCSCSI && (esp->config2 & ESP_CONFIG2_FENAB))
1340                         ecount |= ((unsigned int)esp_read8(ESP_TCHI)) << 16;
1341         }
1342
1343         bytes_sent = esp->data_dma_len;
1344         bytes_sent -= ecount;
1345         bytes_sent -= esp->send_cmd_residual;
1346
1347         /*
1348          * The am53c974 has a DMA 'pecularity'. The doc states:
1349          * In some odd byte conditions, one residual byte will
1350          * be left in the SCSI FIFO, and the FIFO Flags will
1351          * never count to '0 '. When this happens, the residual
1352          * byte should be retrieved via PIO following completion
1353          * of the BLAST operation.
1354          */
1355         if (fifo_cnt == 1 && ent->flags & ESP_CMD_FLAG_RESIDUAL) {
1356                 size_t count = 1;
1357                 size_t offset = bytes_sent;
1358                 u8 bval = esp_read8(ESP_FDATA);
1359
1360                 if (ent->flags & ESP_CMD_FLAG_AUTOSENSE)
1361                         ent->sense_ptr[bytes_sent] = bval;
1362                 else {
1363                         struct esp_cmd_priv *p = ESP_CMD_PRIV(cmd);
1364                         u8 *ptr;
1365
1366                         ptr = scsi_kmap_atomic_sg(p->cur_sg, p->num_sg,
1367                                                   &offset, &count);
1368                         if (likely(ptr)) {
1369                                 *(ptr + offset) = bval;
1370                                 scsi_kunmap_atomic_sg(ptr);
1371                         }
1372                 }
1373                 bytes_sent += fifo_cnt;
1374                 ent->flags &= ~ESP_CMD_FLAG_RESIDUAL;
1375         }
1376         if (!(ent->flags & ESP_CMD_FLAG_WRITE))
1377                 bytes_sent -= fifo_cnt;
1378
1379         flush_fifo = 0;
1380         if (!esp->prev_soff) {
1381                 /* Synchronous data transfer, always flush fifo. */
1382                 flush_fifo = 1;
1383         } else {
1384                 if (esp->rev == ESP100) {
1385                         u32 fflags, phase;
1386
1387                         /* ESP100 has a chip bug where in the synchronous data
1388                          * phase it can mistake a final long REQ pulse from the
1389                          * target as an extra data byte.  Fun.
1390                          *
1391                          * To detect this case we resample the status register
1392                          * and fifo flags.  If we're still in a data phase and
1393                          * we see spurious chunks in the fifo, we return error
1394                          * to the caller which should reset and set things up
1395                          * such that we only try future transfers to this
1396                          * target in synchronous mode.
1397                          */
1398                         esp->sreg = esp_read8(ESP_STATUS);
1399                         phase = esp->sreg & ESP_STAT_PMASK;
1400                         fflags = esp_read8(ESP_FFLAGS);
1401
1402                         if ((phase == ESP_DOP &&
1403                              (fflags & ESP_FF_ONOTZERO)) ||
1404                             (phase == ESP_DIP &&
1405                              (fflags & ESP_FF_FBYTES)))
1406                                 return -1;
1407                 }
1408                 if (!(ent->flags & ESP_CMD_FLAG_WRITE))
1409                         flush_fifo = 1;
1410         }
1411
1412         if (flush_fifo)
1413                 esp_flush_fifo(esp);
1414
1415         return bytes_sent;
1416 }
1417
1418 static void esp_setsync(struct esp *esp, struct esp_target_data *tp,
1419                         u8 scsi_period, u8 scsi_offset,
1420                         u8 esp_stp, u8 esp_soff)
1421 {
1422         spi_period(tp->starget) = scsi_period;
1423         spi_offset(tp->starget) = scsi_offset;
1424         spi_width(tp->starget) = (tp->flags & ESP_TGT_WIDE) ? 1 : 0;
1425
1426         if (esp_soff) {
1427                 esp_stp &= 0x1f;
1428                 esp_soff |= esp->radelay;
1429                 if (esp->rev >= FAS236) {
1430                         u8 bit = ESP_CONFIG3_FSCSI;
1431                         if (esp->rev >= FAS100A)
1432                                 bit = ESP_CONFIG3_FAST;
1433
1434                         if (scsi_period < 50) {
1435                                 if (esp->rev == FASHME)
1436                                         esp_soff &= ~esp->radelay;
1437                                 tp->esp_config3 |= bit;
1438                         } else {
1439                                 tp->esp_config3 &= ~bit;
1440                         }
1441                         esp->prev_cfg3 = tp->esp_config3;
1442                         esp_write8(esp->prev_cfg3, ESP_CFG3);
1443                 }
1444         }
1445
1446         tp->esp_period = esp->prev_stp = esp_stp;
1447         tp->esp_offset = esp->prev_soff = esp_soff;
1448
1449         esp_write8(esp_soff, ESP_SOFF);
1450         esp_write8(esp_stp, ESP_STP);
1451
1452         tp->flags &= ~(ESP_TGT_NEGO_SYNC | ESP_TGT_CHECK_NEGO);
1453
1454         spi_display_xfer_agreement(tp->starget);
1455 }
1456
1457 static void esp_msgin_reject(struct esp *esp)
1458 {
1459         struct esp_cmd_entry *ent = esp->active_cmd;
1460         struct scsi_cmnd *cmd = ent->cmd;
1461         struct esp_target_data *tp;
1462         int tgt;
1463
1464         tgt = cmd->device->id;
1465         tp = &esp->target[tgt];
1466
1467         if (tp->flags & ESP_TGT_NEGO_WIDE) {
1468                 tp->flags &= ~(ESP_TGT_NEGO_WIDE | ESP_TGT_WIDE);
1469
1470                 if (!esp_need_to_nego_sync(tp)) {
1471                         tp->flags &= ~ESP_TGT_CHECK_NEGO;
1472                         scsi_esp_cmd(esp, ESP_CMD_RATN);
1473                 } else {
1474                         esp->msg_out_len =
1475                                 spi_populate_sync_msg(&esp->msg_out[0],
1476                                                       tp->nego_goal_period,
1477                                                       tp->nego_goal_offset);
1478                         tp->flags |= ESP_TGT_NEGO_SYNC;
1479                         scsi_esp_cmd(esp, ESP_CMD_SATN);
1480                 }
1481                 return;
1482         }
1483
1484         if (tp->flags & ESP_TGT_NEGO_SYNC) {
1485                 tp->flags &= ~(ESP_TGT_NEGO_SYNC | ESP_TGT_CHECK_NEGO);
1486                 tp->esp_period = 0;
1487                 tp->esp_offset = 0;
1488                 esp_setsync(esp, tp, 0, 0, 0, 0);
1489                 scsi_esp_cmd(esp, ESP_CMD_RATN);
1490                 return;
1491         }
1492
1493         shost_printk(KERN_INFO, esp->host, "Unexpected MESSAGE REJECT\n");
1494         esp_schedule_reset(esp);
1495 }
1496
1497 static void esp_msgin_sdtr(struct esp *esp, struct esp_target_data *tp)
1498 {
1499         u8 period = esp->msg_in[3];
1500         u8 offset = esp->msg_in[4];
1501         u8 stp;
1502
1503         if (!(tp->flags & ESP_TGT_NEGO_SYNC))
1504                 goto do_reject;
1505
1506         if (offset > 15)
1507                 goto do_reject;
1508
1509         if (offset) {
1510                 int one_clock;
1511
1512                 if (period > esp->max_period) {
1513                         period = offset = 0;
1514                         goto do_sdtr;
1515                 }
1516                 if (period < esp->min_period)
1517                         goto do_reject;
1518
1519                 one_clock = esp->ccycle / 1000;
1520                 stp = DIV_ROUND_UP(period << 2, one_clock);
1521                 if (stp && esp->rev >= FAS236) {
1522                         if (stp >= 50)
1523                                 stp--;
1524                 }
1525         } else {
1526                 stp = 0;
1527         }
1528
1529         esp_setsync(esp, tp, period, offset, stp, offset);
1530         return;
1531
1532 do_reject:
1533         esp->msg_out[0] = MESSAGE_REJECT;
1534         esp->msg_out_len = 1;
1535         scsi_esp_cmd(esp, ESP_CMD_SATN);
1536         return;
1537
1538 do_sdtr:
1539         tp->nego_goal_period = period;
1540         tp->nego_goal_offset = offset;
1541         esp->msg_out_len =
1542                 spi_populate_sync_msg(&esp->msg_out[0],
1543                                       tp->nego_goal_period,
1544                                       tp->nego_goal_offset);
1545         scsi_esp_cmd(esp, ESP_CMD_SATN);
1546 }
1547
1548 static void esp_msgin_wdtr(struct esp *esp, struct esp_target_data *tp)
1549 {
1550         int size = 8 << esp->msg_in[3];
1551         u8 cfg3;
1552
1553         if (esp->rev != FASHME)
1554                 goto do_reject;
1555
1556         if (size != 8 && size != 16)
1557                 goto do_reject;
1558
1559         if (!(tp->flags & ESP_TGT_NEGO_WIDE))
1560                 goto do_reject;
1561
1562         cfg3 = tp->esp_config3;
1563         if (size == 16) {
1564                 tp->flags |= ESP_TGT_WIDE;
1565                 cfg3 |= ESP_CONFIG3_EWIDE;
1566         } else {
1567                 tp->flags &= ~ESP_TGT_WIDE;
1568                 cfg3 &= ~ESP_CONFIG3_EWIDE;
1569         }
1570         tp->esp_config3 = cfg3;
1571         esp->prev_cfg3 = cfg3;
1572         esp_write8(cfg3, ESP_CFG3);
1573
1574         tp->flags &= ~ESP_TGT_NEGO_WIDE;
1575
1576         spi_period(tp->starget) = 0;
1577         spi_offset(tp->starget) = 0;
1578         if (!esp_need_to_nego_sync(tp)) {
1579                 tp->flags &= ~ESP_TGT_CHECK_NEGO;
1580                 scsi_esp_cmd(esp, ESP_CMD_RATN);
1581         } else {
1582                 esp->msg_out_len =
1583                         spi_populate_sync_msg(&esp->msg_out[0],
1584                                               tp->nego_goal_period,
1585                                               tp->nego_goal_offset);
1586                 tp->flags |= ESP_TGT_NEGO_SYNC;
1587                 scsi_esp_cmd(esp, ESP_CMD_SATN);
1588         }
1589         return;
1590
1591 do_reject:
1592         esp->msg_out[0] = MESSAGE_REJECT;
1593         esp->msg_out_len = 1;
1594         scsi_esp_cmd(esp, ESP_CMD_SATN);
1595 }
1596
1597 static void esp_msgin_extended(struct esp *esp)
1598 {
1599         struct esp_cmd_entry *ent = esp->active_cmd;
1600         struct scsi_cmnd *cmd = ent->cmd;
1601         struct esp_target_data *tp;
1602         int tgt = cmd->device->id;
1603
1604         tp = &esp->target[tgt];
1605         if (esp->msg_in[2] == EXTENDED_SDTR) {
1606                 esp_msgin_sdtr(esp, tp);
1607                 return;
1608         }
1609         if (esp->msg_in[2] == EXTENDED_WDTR) {
1610                 esp_msgin_wdtr(esp, tp);
1611                 return;
1612         }
1613
1614         shost_printk(KERN_INFO, esp->host,
1615                      "Unexpected extended msg type %x\n", esp->msg_in[2]);
1616
1617         esp->msg_out[0] = MESSAGE_REJECT;
1618         esp->msg_out_len = 1;
1619         scsi_esp_cmd(esp, ESP_CMD_SATN);
1620 }
1621
1622 /* Analyze msgin bytes received from target so far.  Return non-zero
1623  * if there are more bytes needed to complete the message.
1624  */
1625 static int esp_msgin_process(struct esp *esp)
1626 {
1627         u8 msg0 = esp->msg_in[0];
1628         int len = esp->msg_in_len;
1629
1630         if (msg0 & 0x80) {
1631                 /* Identify */
1632                 shost_printk(KERN_INFO, esp->host,
1633                              "Unexpected msgin identify\n");
1634                 return 0;
1635         }
1636
1637         switch (msg0) {
1638         case EXTENDED_MESSAGE:
1639                 if (len == 1)
1640                         return 1;
1641                 if (len < esp->msg_in[1] + 2)
1642                         return 1;
1643                 esp_msgin_extended(esp);
1644                 return 0;
1645
1646         case IGNORE_WIDE_RESIDUE: {
1647                 struct esp_cmd_entry *ent;
1648                 struct esp_cmd_priv *spriv;
1649                 if (len == 1)
1650                         return 1;
1651
1652                 if (esp->msg_in[1] != 1)
1653                         goto do_reject;
1654
1655                 ent = esp->active_cmd;
1656                 spriv = ESP_CMD_PRIV(ent->cmd);
1657
1658                 if (spriv->cur_residue == sg_dma_len(spriv->cur_sg)) {
1659                         spriv->cur_sg = spriv->prv_sg;
1660                         spriv->cur_residue = 1;
1661                 } else
1662                         spriv->cur_residue++;
1663                 spriv->tot_residue++;
1664                 return 0;
1665         }
1666         case NOP:
1667                 return 0;
1668         case RESTORE_POINTERS:
1669                 esp_restore_pointers(esp, esp->active_cmd);
1670                 return 0;
1671         case SAVE_POINTERS:
1672                 esp_save_pointers(esp, esp->active_cmd);
1673                 return 0;
1674
1675         case COMMAND_COMPLETE:
1676         case DISCONNECT: {
1677                 struct esp_cmd_entry *ent = esp->active_cmd;
1678
1679                 ent->message = msg0;
1680                 esp_event(esp, ESP_EVENT_FREE_BUS);
1681                 esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
1682                 return 0;
1683         }
1684         case MESSAGE_REJECT:
1685                 esp_msgin_reject(esp);
1686                 return 0;
1687
1688         default:
1689         do_reject:
1690                 esp->msg_out[0] = MESSAGE_REJECT;
1691                 esp->msg_out_len = 1;
1692                 scsi_esp_cmd(esp, ESP_CMD_SATN);
1693                 return 0;
1694         }
1695 }
1696
1697 static int esp_process_event(struct esp *esp)
1698 {
1699         int write, i;
1700
1701 again:
1702         write = 0;
1703         esp_log_event("process event %d phase %x\n",
1704                       esp->event, esp->sreg & ESP_STAT_PMASK);
1705         switch (esp->event) {
1706         case ESP_EVENT_CHECK_PHASE:
1707                 switch (esp->sreg & ESP_STAT_PMASK) {
1708                 case ESP_DOP:
1709                         esp_event(esp, ESP_EVENT_DATA_OUT);
1710                         break;
1711                 case ESP_DIP:
1712                         esp_event(esp, ESP_EVENT_DATA_IN);
1713                         break;
1714                 case ESP_STATP:
1715                         esp_flush_fifo(esp);
1716                         scsi_esp_cmd(esp, ESP_CMD_ICCSEQ);
1717                         esp_event(esp, ESP_EVENT_STATUS);
1718                         esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
1719                         return 1;
1720
1721                 case ESP_MOP:
1722                         esp_event(esp, ESP_EVENT_MSGOUT);
1723                         break;
1724
1725                 case ESP_MIP:
1726                         esp_event(esp, ESP_EVENT_MSGIN);
1727                         break;
1728
1729                 case ESP_CMDP:
1730                         esp_event(esp, ESP_EVENT_CMD_START);
1731                         break;
1732
1733                 default:
1734                         shost_printk(KERN_INFO, esp->host,
1735                                      "Unexpected phase, sreg=%02x\n",
1736                                      esp->sreg);
1737                         esp_schedule_reset(esp);
1738                         return 0;
1739                 }
1740                 goto again;
1741
1742         case ESP_EVENT_DATA_IN:
1743                 write = 1;
1744                 fallthrough;
1745
1746         case ESP_EVENT_DATA_OUT: {
1747                 struct esp_cmd_entry *ent = esp->active_cmd;
1748                 struct scsi_cmnd *cmd = ent->cmd;
1749                 dma_addr_t dma_addr = esp_cur_dma_addr(ent, cmd);
1750                 unsigned int dma_len = esp_cur_dma_len(ent, cmd);
1751
1752                 if (esp->rev == ESP100)
1753                         scsi_esp_cmd(esp, ESP_CMD_NULL);
1754
1755                 if (write)
1756                         ent->flags |= ESP_CMD_FLAG_WRITE;
1757                 else
1758                         ent->flags &= ~ESP_CMD_FLAG_WRITE;
1759
1760                 if (esp->ops->dma_length_limit)
1761                         dma_len = esp->ops->dma_length_limit(esp, dma_addr,
1762                                                              dma_len);
1763                 else
1764                         dma_len = esp_dma_length_limit(esp, dma_addr, dma_len);
1765
1766                 esp->data_dma_len = dma_len;
1767
1768                 if (!dma_len) {
1769                         shost_printk(KERN_ERR, esp->host,
1770                                      "DMA length is zero!\n");
1771                         shost_printk(KERN_ERR, esp->host,
1772                                      "cur adr[%08llx] len[%08x]\n",
1773                                      (unsigned long long)esp_cur_dma_addr(ent, cmd),
1774                                      esp_cur_dma_len(ent, cmd));
1775                         esp_schedule_reset(esp);
1776                         return 0;
1777                 }
1778
1779                 esp_log_datastart("start data addr[%08llx] len[%u] write(%d)\n",
1780                                   (unsigned long long)dma_addr, dma_len, write);
1781
1782                 esp->ops->send_dma_cmd(esp, dma_addr, dma_len, dma_len,
1783                                        write, ESP_CMD_DMA | ESP_CMD_TI);
1784                 esp_event(esp, ESP_EVENT_DATA_DONE);
1785                 break;
1786         }
1787         case ESP_EVENT_DATA_DONE: {
1788                 struct esp_cmd_entry *ent = esp->active_cmd;
1789                 struct scsi_cmnd *cmd = ent->cmd;
1790                 int bytes_sent;
1791
1792                 if (esp->ops->dma_error(esp)) {
1793                         shost_printk(KERN_INFO, esp->host,
1794                                      "data done, DMA error, resetting\n");
1795                         esp_schedule_reset(esp);
1796                         return 0;
1797                 }
1798
1799                 if (ent->flags & ESP_CMD_FLAG_WRITE) {
1800                         /* XXX parity errors, etc. XXX */
1801
1802                         esp->ops->dma_drain(esp);
1803                 }
1804                 esp->ops->dma_invalidate(esp);
1805
1806                 if (esp->ireg != ESP_INTR_BSERV) {
1807                         /* We should always see exactly a bus-service
1808                          * interrupt at the end of a successful transfer.
1809                          */
1810                         shost_printk(KERN_INFO, esp->host,
1811                                      "data done, not BSERV, resetting\n");
1812                         esp_schedule_reset(esp);
1813                         return 0;
1814                 }
1815
1816                 bytes_sent = esp_data_bytes_sent(esp, ent, cmd);
1817
1818                 esp_log_datadone("data done flgs[%x] sent[%d]\n",
1819                                  ent->flags, bytes_sent);
1820
1821                 if (bytes_sent < 0) {
1822                         /* XXX force sync mode for this target XXX */
1823                         esp_schedule_reset(esp);
1824                         return 0;
1825                 }
1826
1827                 esp_advance_dma(esp, ent, cmd, bytes_sent);
1828                 esp_event(esp, ESP_EVENT_CHECK_PHASE);
1829                 goto again;
1830         }
1831
1832         case ESP_EVENT_STATUS: {
1833                 struct esp_cmd_entry *ent = esp->active_cmd;
1834
1835                 if (esp->ireg & ESP_INTR_FDONE) {
1836                         ent->status = esp_read8(ESP_FDATA);
1837                         ent->message = esp_read8(ESP_FDATA);
1838                         scsi_esp_cmd(esp, ESP_CMD_MOK);
1839                 } else if (esp->ireg == ESP_INTR_BSERV) {
1840                         ent->status = esp_read8(ESP_FDATA);
1841                         ent->message = 0xff;
1842                         esp_event(esp, ESP_EVENT_MSGIN);
1843                         return 0;
1844                 }
1845
1846                 if (ent->message != COMMAND_COMPLETE) {
1847                         shost_printk(KERN_INFO, esp->host,
1848                                      "Unexpected message %x in status\n",
1849                                      ent->message);
1850                         esp_schedule_reset(esp);
1851                         return 0;
1852                 }
1853
1854                 esp_event(esp, ESP_EVENT_FREE_BUS);
1855                 esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
1856                 break;
1857         }
1858         case ESP_EVENT_FREE_BUS: {
1859                 struct esp_cmd_entry *ent = esp->active_cmd;
1860                 struct scsi_cmnd *cmd = ent->cmd;
1861
1862                 if (ent->message == COMMAND_COMPLETE ||
1863                     ent->message == DISCONNECT)
1864                         scsi_esp_cmd(esp, ESP_CMD_ESEL);
1865
1866                 if (ent->message == COMMAND_COMPLETE) {
1867                         esp_log_cmddone("Command done status[%x] message[%x]\n",
1868                                         ent->status, ent->message);
1869                         if (ent->status == SAM_STAT_TASK_SET_FULL)
1870                                 esp_event_queue_full(esp, ent);
1871
1872                         if (ent->status == SAM_STAT_CHECK_CONDITION &&
1873                             !(ent->flags & ESP_CMD_FLAG_AUTOSENSE)) {
1874                                 ent->flags |= ESP_CMD_FLAG_AUTOSENSE;
1875                                 esp_autosense(esp, ent);
1876                         } else {
1877                                 esp_cmd_is_done(esp, ent, cmd,
1878                                                 compose_result(ent->status,
1879                                                                ent->message,
1880                                                                DID_OK));
1881                         }
1882                 } else if (ent->message == DISCONNECT) {
1883                         esp_log_disconnect("Disconnecting tgt[%d] tag[%x:%x]\n",
1884                                            cmd->device->id,
1885                                            ent->tag[0], ent->tag[1]);
1886
1887                         esp->active_cmd = NULL;
1888                         esp_maybe_execute_command(esp);
1889                 } else {
1890                         shost_printk(KERN_INFO, esp->host,
1891                                      "Unexpected message %x in freebus\n",
1892                                      ent->message);
1893                         esp_schedule_reset(esp);
1894                         return 0;
1895                 }
1896                 if (esp->active_cmd)
1897                         esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
1898                 break;
1899         }
1900         case ESP_EVENT_MSGOUT: {
1901                 scsi_esp_cmd(esp, ESP_CMD_FLUSH);
1902
1903                 if (esp_debug & ESP_DEBUG_MSGOUT) {
1904                         int i;
1905                         printk("ESP: Sending message [ ");
1906                         for (i = 0; i < esp->msg_out_len; i++)
1907                                 printk("%02x ", esp->msg_out[i]);
1908                         printk("]\n");
1909                 }
1910
1911                 if (esp->rev == FASHME) {
1912                         int i;
1913
1914                         /* Always use the fifo.  */
1915                         for (i = 0; i < esp->msg_out_len; i++) {
1916                                 esp_write8(esp->msg_out[i], ESP_FDATA);
1917                                 esp_write8(0, ESP_FDATA);
1918                         }
1919                         scsi_esp_cmd(esp, ESP_CMD_TI);
1920                 } else {
1921                         if (esp->msg_out_len == 1) {
1922                                 esp_write8(esp->msg_out[0], ESP_FDATA);
1923                                 scsi_esp_cmd(esp, ESP_CMD_TI);
1924                         } else if (esp->flags & ESP_FLAG_USE_FIFO) {
1925                                 for (i = 0; i < esp->msg_out_len; i++)
1926                                         esp_write8(esp->msg_out[i], ESP_FDATA);
1927                                 scsi_esp_cmd(esp, ESP_CMD_TI);
1928                         } else {
1929                                 /* Use DMA. */
1930                                 memcpy(esp->command_block,
1931                                        esp->msg_out,
1932                                        esp->msg_out_len);
1933
1934                                 esp->ops->send_dma_cmd(esp,
1935                                                        esp->command_block_dma,
1936                                                        esp->msg_out_len,
1937                                                        esp->msg_out_len,
1938                                                        0,
1939                                                        ESP_CMD_DMA|ESP_CMD_TI);
1940                         }
1941                 }
1942                 esp_event(esp, ESP_EVENT_MSGOUT_DONE);
1943                 break;
1944         }
1945         case ESP_EVENT_MSGOUT_DONE:
1946                 if (esp->rev == FASHME) {
1947                         scsi_esp_cmd(esp, ESP_CMD_FLUSH);
1948                 } else {
1949                         if (esp->msg_out_len > 1)
1950                                 esp->ops->dma_invalidate(esp);
1951
1952                         /* XXX if the chip went into disconnected mode,
1953                          * we can't run the phase state machine anyway.
1954                          */
1955                         if (!(esp->ireg & ESP_INTR_DC))
1956                                 scsi_esp_cmd(esp, ESP_CMD_NULL);
1957                 }
1958
1959                 esp->msg_out_len = 0;
1960
1961                 esp_event(esp, ESP_EVENT_CHECK_PHASE);
1962                 goto again;
1963         case ESP_EVENT_MSGIN:
1964                 if (esp->ireg & ESP_INTR_BSERV) {
1965                         if (esp->rev == FASHME) {
1966                                 if (!(esp_read8(ESP_STATUS2) &
1967                                       ESP_STAT2_FEMPTY))
1968                                         scsi_esp_cmd(esp, ESP_CMD_FLUSH);
1969                         } else {
1970                                 scsi_esp_cmd(esp, ESP_CMD_FLUSH);
1971                                 if (esp->rev == ESP100)
1972                                         scsi_esp_cmd(esp, ESP_CMD_NULL);
1973                         }
1974                         scsi_esp_cmd(esp, ESP_CMD_TI);
1975                         esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
1976                         return 1;
1977                 }
1978                 if (esp->ireg & ESP_INTR_FDONE) {
1979                         u8 val;
1980
1981                         if (esp->rev == FASHME)
1982                                 val = esp->fifo[0];
1983                         else
1984                                 val = esp_read8(ESP_FDATA);
1985                         esp->msg_in[esp->msg_in_len++] = val;
1986
1987                         esp_log_msgin("Got msgin byte %x\n", val);
1988
1989                         if (!esp_msgin_process(esp))
1990                                 esp->msg_in_len = 0;
1991
1992                         if (esp->rev == FASHME)
1993                                 scsi_esp_cmd(esp, ESP_CMD_FLUSH);
1994
1995                         scsi_esp_cmd(esp, ESP_CMD_MOK);
1996
1997                         /* Check whether a bus reset is to be done next */
1998                         if (esp->event == ESP_EVENT_RESET)
1999                                 return 0;
2000
2001                         if (esp->event != ESP_EVENT_FREE_BUS)
2002                                 esp_event(esp, ESP_EVENT_CHECK_PHASE);
2003                 } else {
2004                         shost_printk(KERN_INFO, esp->host,
2005                                      "MSGIN neither BSERV not FDON, resetting");
2006                         esp_schedule_reset(esp);
2007                         return 0;
2008                 }
2009                 break;
2010         case ESP_EVENT_CMD_START:
2011                 memcpy(esp->command_block, esp->cmd_bytes_ptr,
2012                        esp->cmd_bytes_left);
2013                 esp_send_dma_cmd(esp, esp->cmd_bytes_left, 16, ESP_CMD_TI);
2014                 esp_event(esp, ESP_EVENT_CMD_DONE);
2015                 esp->flags |= ESP_FLAG_QUICKIRQ_CHECK;
2016                 break;
2017         case ESP_EVENT_CMD_DONE:
2018                 esp->ops->dma_invalidate(esp);
2019                 if (esp->ireg & ESP_INTR_BSERV) {
2020                         esp_event(esp, ESP_EVENT_CHECK_PHASE);
2021                         goto again;
2022                 }
2023                 esp_schedule_reset(esp);
2024                 return 0;
2025
2026         case ESP_EVENT_RESET:
2027                 scsi_esp_cmd(esp, ESP_CMD_RS);
2028                 break;
2029
2030         default:
2031                 shost_printk(KERN_INFO, esp->host,
2032                              "Unexpected event %x, resetting\n", esp->event);
2033                 esp_schedule_reset(esp);
2034                 return 0;
2035         }
2036         return 1;
2037 }
2038
2039 static void esp_reset_cleanup_one(struct esp *esp, struct esp_cmd_entry *ent)
2040 {
2041         struct scsi_cmnd *cmd = ent->cmd;
2042
2043         esp_unmap_dma(esp, cmd);
2044         esp_free_lun_tag(ent, cmd->device->hostdata);
2045         cmd->result = DID_RESET << 16;
2046
2047         if (ent->flags & ESP_CMD_FLAG_AUTOSENSE)
2048                 esp_unmap_sense(esp, ent);
2049
2050         cmd->scsi_done(cmd);
2051         list_del(&ent->list);
2052         esp_put_ent(esp, ent);
2053 }
2054
2055 static void esp_clear_hold(struct scsi_device *dev, void *data)
2056 {
2057         struct esp_lun_data *lp = dev->hostdata;
2058
2059         BUG_ON(lp->num_tagged);
2060         lp->hold = 0;
2061 }
2062
2063 static void esp_reset_cleanup(struct esp *esp)
2064 {
2065         struct esp_cmd_entry *ent, *tmp;
2066         int i;
2067
2068         list_for_each_entry_safe(ent, tmp, &esp->queued_cmds, list) {
2069                 struct scsi_cmnd *cmd = ent->cmd;
2070
2071                 list_del(&ent->list);
2072                 cmd->result = DID_RESET << 16;
2073                 cmd->scsi_done(cmd);
2074                 esp_put_ent(esp, ent);
2075         }
2076
2077         list_for_each_entry_safe(ent, tmp, &esp->active_cmds, list) {
2078                 if (ent == esp->active_cmd)
2079                         esp->active_cmd = NULL;
2080                 esp_reset_cleanup_one(esp, ent);
2081         }
2082
2083         BUG_ON(esp->active_cmd != NULL);
2084
2085         /* Force renegotiation of sync/wide transfers.  */
2086         for (i = 0; i < ESP_MAX_TARGET; i++) {
2087                 struct esp_target_data *tp = &esp->target[i];
2088
2089                 tp->esp_period = 0;
2090                 tp->esp_offset = 0;
2091                 tp->esp_config3 &= ~(ESP_CONFIG3_EWIDE |
2092                                      ESP_CONFIG3_FSCSI |
2093                                      ESP_CONFIG3_FAST);
2094                 tp->flags &= ~ESP_TGT_WIDE;
2095                 tp->flags |= ESP_TGT_CHECK_NEGO;
2096
2097                 if (tp->starget)
2098                         __starget_for_each_device(tp->starget, NULL,
2099                                                   esp_clear_hold);
2100         }
2101         esp->flags &= ~ESP_FLAG_RESETTING;
2102 }
2103
2104 /* Runs under host->lock */
2105 static void __esp_interrupt(struct esp *esp)
2106 {
2107         int finish_reset, intr_done;
2108         u8 phase;
2109
2110        /*
2111         * Once INTRPT is read STATUS and SSTEP are cleared.
2112         */
2113         esp->sreg = esp_read8(ESP_STATUS);
2114         esp->seqreg = esp_read8(ESP_SSTEP);
2115         esp->ireg = esp_read8(ESP_INTRPT);
2116
2117         if (esp->flags & ESP_FLAG_RESETTING) {
2118                 finish_reset = 1;
2119         } else {
2120                 if (esp_check_gross_error(esp))
2121                         return;
2122
2123                 finish_reset = esp_check_spur_intr(esp);
2124                 if (finish_reset < 0)
2125                         return;
2126         }
2127
2128         if (esp->ireg & ESP_INTR_SR)
2129                 finish_reset = 1;
2130
2131         if (finish_reset) {
2132                 esp_reset_cleanup(esp);
2133                 if (esp->eh_reset) {
2134                         complete(esp->eh_reset);
2135                         esp->eh_reset = NULL;
2136                 }
2137                 return;
2138         }
2139
2140         phase = (esp->sreg & ESP_STAT_PMASK);
2141         if (esp->rev == FASHME) {
2142                 if (((phase != ESP_DIP && phase != ESP_DOP) &&
2143                      esp->select_state == ESP_SELECT_NONE &&
2144                      esp->event != ESP_EVENT_STATUS &&
2145                      esp->event != ESP_EVENT_DATA_DONE) ||
2146                     (esp->ireg & ESP_INTR_RSEL)) {
2147                         esp->sreg2 = esp_read8(ESP_STATUS2);
2148                         if (!(esp->sreg2 & ESP_STAT2_FEMPTY) ||
2149                             (esp->sreg2 & ESP_STAT2_F1BYTE))
2150                                 hme_read_fifo(esp);
2151                 }
2152         }
2153
2154         esp_log_intr("intr sreg[%02x] seqreg[%02x] "
2155                      "sreg2[%02x] ireg[%02x]\n",
2156                      esp->sreg, esp->seqreg, esp->sreg2, esp->ireg);
2157
2158         intr_done = 0;
2159
2160         if (esp->ireg & (ESP_INTR_S | ESP_INTR_SATN | ESP_INTR_IC)) {
2161                 shost_printk(KERN_INFO, esp->host,
2162                              "unexpected IREG %02x\n", esp->ireg);
2163                 if (esp->ireg & ESP_INTR_IC)
2164                         esp_dump_cmd_log(esp);
2165
2166                 esp_schedule_reset(esp);
2167         } else {
2168                 if (esp->ireg & ESP_INTR_RSEL) {
2169                         if (esp->active_cmd)
2170                                 (void) esp_finish_select(esp);
2171                         intr_done = esp_reconnect(esp);
2172                 } else {
2173                         /* Some combination of FDONE, BSERV, DC. */
2174                         if (esp->select_state != ESP_SELECT_NONE)
2175                                 intr_done = esp_finish_select(esp);
2176                 }
2177         }
2178         while (!intr_done)
2179                 intr_done = esp_process_event(esp);
2180 }
2181
2182 irqreturn_t scsi_esp_intr(int irq, void *dev_id)
2183 {
2184         struct esp *esp = dev_id;
2185         unsigned long flags;
2186         irqreturn_t ret;
2187
2188         spin_lock_irqsave(esp->host->host_lock, flags);
2189         ret = IRQ_NONE;
2190         if (esp->ops->irq_pending(esp)) {
2191                 ret = IRQ_HANDLED;
2192                 for (;;) {
2193                         int i;
2194
2195                         __esp_interrupt(esp);
2196                         if (!(esp->flags & ESP_FLAG_QUICKIRQ_CHECK))
2197                                 break;
2198                         esp->flags &= ~ESP_FLAG_QUICKIRQ_CHECK;
2199
2200                         for (i = 0; i < ESP_QUICKIRQ_LIMIT; i++) {
2201                                 if (esp->ops->irq_pending(esp))
2202                                         break;
2203                         }
2204                         if (i == ESP_QUICKIRQ_LIMIT)
2205                                 break;
2206                 }
2207         }
2208         spin_unlock_irqrestore(esp->host->host_lock, flags);
2209
2210         return ret;
2211 }
2212 EXPORT_SYMBOL(scsi_esp_intr);
2213
2214 static void esp_get_revision(struct esp *esp)
2215 {
2216         u8 val;
2217
2218         esp->config1 = (ESP_CONFIG1_PENABLE | (esp->scsi_id & 7));
2219         if (esp->config2 == 0) {
2220                 esp->config2 = (ESP_CONFIG2_SCSI2ENAB | ESP_CONFIG2_REGPARITY);
2221                 esp_write8(esp->config2, ESP_CFG2);
2222
2223                 val = esp_read8(ESP_CFG2);
2224                 val &= ~ESP_CONFIG2_MAGIC;
2225
2226                 esp->config2 = 0;
2227                 if (val != (ESP_CONFIG2_SCSI2ENAB | ESP_CONFIG2_REGPARITY)) {
2228                         /*
2229                          * If what we write to cfg2 does not come back,
2230                          * cfg2 is not implemented.
2231                          * Therefore this must be a plain esp100.
2232                          */
2233                         esp->rev = ESP100;
2234                         return;
2235                 }
2236         }
2237
2238         esp_set_all_config3(esp, 5);
2239         esp->prev_cfg3 = 5;
2240         esp_write8(esp->config2, ESP_CFG2);
2241         esp_write8(0, ESP_CFG3);
2242         esp_write8(esp->prev_cfg3, ESP_CFG3);
2243
2244         val = esp_read8(ESP_CFG3);
2245         if (val != 5) {
2246                 /* The cfg2 register is implemented, however
2247                  * cfg3 is not, must be esp100a.
2248                  */
2249                 esp->rev = ESP100A;
2250         } else {
2251                 esp_set_all_config3(esp, 0);
2252                 esp->prev_cfg3 = 0;
2253                 esp_write8(esp->prev_cfg3, ESP_CFG3);
2254
2255                 /* All of cfg{1,2,3} implemented, must be one of
2256                  * the fas variants, figure out which one.
2257                  */
2258                 if (esp->cfact == 0 || esp->cfact > ESP_CCF_F5) {
2259                         esp->rev = FAST;
2260                         esp->sync_defp = SYNC_DEFP_FAST;
2261                 } else {
2262                         esp->rev = ESP236;
2263                 }
2264         }
2265 }
2266
2267 static void esp_init_swstate(struct esp *esp)
2268 {
2269         int i;
2270
2271         INIT_LIST_HEAD(&esp->queued_cmds);
2272         INIT_LIST_HEAD(&esp->active_cmds);
2273         INIT_LIST_HEAD(&esp->esp_cmd_pool);
2274
2275         /* Start with a clear state, domain validation (via ->slave_configure,
2276          * spi_dv_device()) will attempt to enable SYNC, WIDE, and tagged
2277          * commands.
2278          */
2279         for (i = 0 ; i < ESP_MAX_TARGET; i++) {
2280                 esp->target[i].flags = 0;
2281                 esp->target[i].nego_goal_period = 0;
2282                 esp->target[i].nego_goal_offset = 0;
2283                 esp->target[i].nego_goal_width = 0;
2284                 esp->target[i].nego_goal_tags = 0;
2285         }
2286 }
2287
2288 /* This places the ESP into a known state at boot time. */
2289 static void esp_bootup_reset(struct esp *esp)
2290 {
2291         u8 val;
2292
2293         /* Reset the DMA */
2294         esp->ops->reset_dma(esp);
2295
2296         /* Reset the ESP */
2297         esp_reset_esp(esp);
2298
2299         /* Reset the SCSI bus, but tell ESP not to generate an irq */
2300         val = esp_read8(ESP_CFG1);
2301         val |= ESP_CONFIG1_SRRDISAB;
2302         esp_write8(val, ESP_CFG1);
2303
2304         scsi_esp_cmd(esp, ESP_CMD_RS);
2305         udelay(400);
2306
2307         esp_write8(esp->config1, ESP_CFG1);
2308
2309         /* Eat any bitrot in the chip and we are done... */
2310         esp_read8(ESP_INTRPT);
2311 }
2312
2313 static void esp_set_clock_params(struct esp *esp)
2314 {
2315         int fhz;
2316         u8 ccf;
2317
2318         /* This is getting messy but it has to be done correctly or else
2319          * you get weird behavior all over the place.  We are trying to
2320          * basically figure out three pieces of information.
2321          *
2322          * a) Clock Conversion Factor
2323          *
2324          *    This is a representation of the input crystal clock frequency
2325          *    going into the ESP on this machine.  Any operation whose timing
2326          *    is longer than 400ns depends on this value being correct.  For
2327          *    example, you'll get blips for arbitration/selection during high
2328          *    load or with multiple targets if this is not set correctly.
2329          *
2330          * b) Selection Time-Out
2331          *
2332          *    The ESP isn't very bright and will arbitrate for the bus and try
2333          *    to select a target forever if you let it.  This value tells the
2334          *    ESP when it has taken too long to negotiate and that it should
2335          *    interrupt the CPU so we can see what happened.  The value is
2336          *    computed as follows (from NCR/Symbios chip docs).
2337          *
2338          *          (Time Out Period) *  (Input Clock)
2339          *    STO = ----------------------------------
2340          *          (8192) * (Clock Conversion Factor)
2341          *
2342          *    We use a time out period of 250ms (ESP_BUS_TIMEOUT).
2343          *
2344          * c) Imperical constants for synchronous offset and transfer period
2345          *    register values
2346          *
2347          *    This entails the smallest and largest sync period we could ever
2348          *    handle on this ESP.
2349          */
2350         fhz = esp->cfreq;
2351
2352         ccf = ((fhz / 1000000) + 4) / 5;
2353         if (ccf == 1)
2354                 ccf = 2;
2355
2356         /* If we can't find anything reasonable, just assume 20MHZ.
2357          * This is the clock frequency of the older sun4c's where I've
2358          * been unable to find the clock-frequency PROM property.  All
2359          * other machines provide useful values it seems.
2360          */
2361         if (fhz <= 5000000 || ccf < 1 || ccf > 8) {
2362                 fhz = 20000000;
2363                 ccf = 4;
2364         }
2365
2366         esp->cfact = (ccf == 8 ? 0 : ccf);
2367         esp->cfreq = fhz;
2368         esp->ccycle = ESP_HZ_TO_CYCLE(fhz);
2369         esp->ctick = ESP_TICK(ccf, esp->ccycle);
2370         esp->neg_defp = ESP_NEG_DEFP(fhz, ccf);
2371         esp->sync_defp = SYNC_DEFP_SLOW;
2372 }
2373
2374 static const char *esp_chip_names[] = {
2375         "ESP100",
2376         "ESP100A",
2377         "ESP236",
2378         "FAS236",
2379         "AM53C974",
2380         "53CF9x-2",
2381         "FAS100A",
2382         "FAST",
2383         "FASHME",
2384 };
2385
2386 static struct scsi_transport_template *esp_transport_template;
2387
2388 int scsi_esp_register(struct esp *esp)
2389 {
2390         static int instance;
2391         int err;
2392
2393         if (!esp->num_tags)
2394                 esp->num_tags = ESP_DEFAULT_TAGS;
2395         esp->host->transportt = esp_transport_template;
2396         esp->host->max_lun = ESP_MAX_LUN;
2397         esp->host->cmd_per_lun = 2;
2398         esp->host->unique_id = instance;
2399
2400         esp_set_clock_params(esp);
2401
2402         esp_get_revision(esp);
2403
2404         esp_init_swstate(esp);
2405
2406         esp_bootup_reset(esp);
2407
2408         dev_printk(KERN_INFO, esp->dev, "esp%u: regs[%1p:%1p] irq[%u]\n",
2409                    esp->host->unique_id, esp->regs, esp->dma_regs,
2410                    esp->host->irq);
2411         dev_printk(KERN_INFO, esp->dev,
2412                    "esp%u: is a %s, %u MHz (ccf=%u), SCSI ID %u\n",
2413                    esp->host->unique_id, esp_chip_names[esp->rev],
2414                    esp->cfreq / 1000000, esp->cfact, esp->scsi_id);
2415
2416         /* Let the SCSI bus reset settle. */
2417         ssleep(esp_bus_reset_settle);
2418
2419         err = scsi_add_host(esp->host, esp->dev);
2420         if (err)
2421                 return err;
2422
2423         instance++;
2424
2425         scsi_scan_host(esp->host);
2426
2427         return 0;
2428 }
2429 EXPORT_SYMBOL(scsi_esp_register);
2430
2431 void scsi_esp_unregister(struct esp *esp)
2432 {
2433         scsi_remove_host(esp->host);
2434 }
2435 EXPORT_SYMBOL(scsi_esp_unregister);
2436
2437 static int esp_target_alloc(struct scsi_target *starget)
2438 {
2439         struct esp *esp = shost_priv(dev_to_shost(&starget->dev));
2440         struct esp_target_data *tp = &esp->target[starget->id];
2441
2442         tp->starget = starget;
2443
2444         return 0;
2445 }
2446
2447 static void esp_target_destroy(struct scsi_target *starget)
2448 {
2449         struct esp *esp = shost_priv(dev_to_shost(&starget->dev));
2450         struct esp_target_data *tp = &esp->target[starget->id];
2451
2452         tp->starget = NULL;
2453 }
2454
2455 static int esp_slave_alloc(struct scsi_device *dev)
2456 {
2457         struct esp *esp = shost_priv(dev->host);
2458         struct esp_target_data *tp = &esp->target[dev->id];
2459         struct esp_lun_data *lp;
2460
2461         lp = kzalloc(sizeof(*lp), GFP_KERNEL);
2462         if (!lp)
2463                 return -ENOMEM;
2464         dev->hostdata = lp;
2465
2466         spi_min_period(tp->starget) = esp->min_period;
2467         spi_max_offset(tp->starget) = 15;
2468
2469         if (esp->flags & ESP_FLAG_WIDE_CAPABLE)
2470                 spi_max_width(tp->starget) = 1;
2471         else
2472                 spi_max_width(tp->starget) = 0;
2473
2474         return 0;
2475 }
2476
2477 static int esp_slave_configure(struct scsi_device *dev)
2478 {
2479         struct esp *esp = shost_priv(dev->host);
2480         struct esp_target_data *tp = &esp->target[dev->id];
2481
2482         if (dev->tagged_supported)
2483                 scsi_change_queue_depth(dev, esp->num_tags);
2484
2485         tp->flags |= ESP_TGT_DISCONNECT;
2486
2487         if (!spi_initial_dv(dev->sdev_target))
2488                 spi_dv_device(dev);
2489
2490         return 0;
2491 }
2492
2493 static void esp_slave_destroy(struct scsi_device *dev)
2494 {
2495         struct esp_lun_data *lp = dev->hostdata;
2496
2497         kfree(lp);
2498         dev->hostdata = NULL;
2499 }
2500
2501 static int esp_eh_abort_handler(struct scsi_cmnd *cmd)
2502 {
2503         struct esp *esp = shost_priv(cmd->device->host);
2504         struct esp_cmd_entry *ent, *tmp;
2505         struct completion eh_done;
2506         unsigned long flags;
2507
2508         /* XXX This helps a lot with debugging but might be a bit
2509          * XXX much for the final driver.
2510          */
2511         spin_lock_irqsave(esp->host->host_lock, flags);
2512         shost_printk(KERN_ERR, esp->host, "Aborting command [%p:%02x]\n",
2513                      cmd, cmd->cmnd[0]);
2514         ent = esp->active_cmd;
2515         if (ent)
2516                 shost_printk(KERN_ERR, esp->host,
2517                              "Current command [%p:%02x]\n",
2518                              ent->cmd, ent->cmd->cmnd[0]);
2519         list_for_each_entry(ent, &esp->queued_cmds, list) {
2520                 shost_printk(KERN_ERR, esp->host, "Queued command [%p:%02x]\n",
2521                              ent->cmd, ent->cmd->cmnd[0]);
2522         }
2523         list_for_each_entry(ent, &esp->active_cmds, list) {
2524                 shost_printk(KERN_ERR, esp->host, " Active command [%p:%02x]\n",
2525                              ent->cmd, ent->cmd->cmnd[0]);
2526         }
2527         esp_dump_cmd_log(esp);
2528         spin_unlock_irqrestore(esp->host->host_lock, flags);
2529
2530         spin_lock_irqsave(esp->host->host_lock, flags);
2531
2532         ent = NULL;
2533         list_for_each_entry(tmp, &esp->queued_cmds, list) {
2534                 if (tmp->cmd == cmd) {
2535                         ent = tmp;
2536                         break;
2537                 }
2538         }
2539
2540         if (ent) {
2541                 /* Easiest case, we didn't even issue the command
2542                  * yet so it is trivial to abort.
2543                  */
2544                 list_del(&ent->list);
2545
2546                 cmd->result = DID_ABORT << 16;
2547                 cmd->scsi_done(cmd);
2548
2549                 esp_put_ent(esp, ent);
2550
2551                 goto out_success;
2552         }
2553
2554         init_completion(&eh_done);
2555
2556         ent = esp->active_cmd;
2557         if (ent && ent->cmd == cmd) {
2558                 /* Command is the currently active command on
2559                  * the bus.  If we already have an output message
2560                  * pending, no dice.
2561                  */
2562                 if (esp->msg_out_len)
2563                         goto out_failure;
2564
2565                 /* Send out an abort, encouraging the target to
2566                  * go to MSGOUT phase by asserting ATN.
2567                  */
2568                 esp->msg_out[0] = ABORT_TASK_SET;
2569                 esp->msg_out_len = 1;
2570                 ent->eh_done = &eh_done;
2571
2572                 scsi_esp_cmd(esp, ESP_CMD_SATN);
2573         } else {
2574                 /* The command is disconnected.  This is not easy to
2575                  * abort.  For now we fail and let the scsi error
2576                  * handling layer go try a scsi bus reset or host
2577                  * reset.
2578                  *
2579                  * What we could do is put together a scsi command
2580                  * solely for the purpose of sending an abort message
2581                  * to the target.  Coming up with all the code to
2582                  * cook up scsi commands, special case them everywhere,
2583                  * etc. is for questionable gain and it would be better
2584                  * if the generic scsi error handling layer could do at
2585                  * least some of that for us.
2586                  *
2587                  * Anyways this is an area for potential future improvement
2588                  * in this driver.
2589                  */
2590                 goto out_failure;
2591         }
2592
2593         spin_unlock_irqrestore(esp->host->host_lock, flags);
2594
2595         if (!wait_for_completion_timeout(&eh_done, 5 * HZ)) {
2596                 spin_lock_irqsave(esp->host->host_lock, flags);
2597                 ent->eh_done = NULL;
2598                 spin_unlock_irqrestore(esp->host->host_lock, flags);
2599
2600                 return FAILED;
2601         }
2602
2603         return SUCCESS;
2604
2605 out_success:
2606         spin_unlock_irqrestore(esp->host->host_lock, flags);
2607         return SUCCESS;
2608
2609 out_failure:
2610         /* XXX This might be a good location to set ESP_TGT_BROKEN
2611          * XXX since we know which target/lun in particular is
2612          * XXX causing trouble.
2613          */
2614         spin_unlock_irqrestore(esp->host->host_lock, flags);
2615         return FAILED;
2616 }
2617
2618 static int esp_eh_bus_reset_handler(struct scsi_cmnd *cmd)
2619 {
2620         struct esp *esp = shost_priv(cmd->device->host);
2621         struct completion eh_reset;
2622         unsigned long flags;
2623
2624         init_completion(&eh_reset);
2625
2626         spin_lock_irqsave(esp->host->host_lock, flags);
2627
2628         esp->eh_reset = &eh_reset;
2629
2630         /* XXX This is too simple... We should add lots of
2631          * XXX checks here so that if we find that the chip is
2632          * XXX very wedged we return failure immediately so
2633          * XXX that we can perform a full chip reset.
2634          */
2635         esp->flags |= ESP_FLAG_RESETTING;
2636         scsi_esp_cmd(esp, ESP_CMD_RS);
2637
2638         spin_unlock_irqrestore(esp->host->host_lock, flags);
2639
2640         ssleep(esp_bus_reset_settle);
2641
2642         if (!wait_for_completion_timeout(&eh_reset, 5 * HZ)) {
2643                 spin_lock_irqsave(esp->host->host_lock, flags);
2644                 esp->eh_reset = NULL;
2645                 spin_unlock_irqrestore(esp->host->host_lock, flags);
2646
2647                 return FAILED;
2648         }
2649
2650         return SUCCESS;
2651 }
2652
2653 /* All bets are off, reset the entire device.  */
2654 static int esp_eh_host_reset_handler(struct scsi_cmnd *cmd)
2655 {
2656         struct esp *esp = shost_priv(cmd->device->host);
2657         unsigned long flags;
2658
2659         spin_lock_irqsave(esp->host->host_lock, flags);
2660         esp_bootup_reset(esp);
2661         esp_reset_cleanup(esp);
2662         spin_unlock_irqrestore(esp->host->host_lock, flags);
2663
2664         ssleep(esp_bus_reset_settle);
2665
2666         return SUCCESS;
2667 }
2668
2669 static const char *esp_info(struct Scsi_Host *host)
2670 {
2671         return "esp";
2672 }
2673
2674 struct scsi_host_template scsi_esp_template = {
2675         .module                 = THIS_MODULE,
2676         .name                   = "esp",
2677         .info                   = esp_info,
2678         .queuecommand           = esp_queuecommand,
2679         .target_alloc           = esp_target_alloc,
2680         .target_destroy         = esp_target_destroy,
2681         .slave_alloc            = esp_slave_alloc,
2682         .slave_configure        = esp_slave_configure,
2683         .slave_destroy          = esp_slave_destroy,
2684         .eh_abort_handler       = esp_eh_abort_handler,
2685         .eh_bus_reset_handler   = esp_eh_bus_reset_handler,
2686         .eh_host_reset_handler  = esp_eh_host_reset_handler,
2687         .can_queue              = 7,
2688         .this_id                = 7,
2689         .sg_tablesize           = SG_ALL,
2690         .max_sectors            = 0xffff,
2691         .skip_settle_delay      = 1,
2692 };
2693 EXPORT_SYMBOL(scsi_esp_template);
2694
2695 static void esp_get_signalling(struct Scsi_Host *host)
2696 {
2697         struct esp *esp = shost_priv(host);
2698         enum spi_signal_type type;
2699
2700         if (esp->flags & ESP_FLAG_DIFFERENTIAL)
2701                 type = SPI_SIGNAL_HVD;
2702         else
2703                 type = SPI_SIGNAL_SE;
2704
2705         spi_signalling(host) = type;
2706 }
2707
2708 static void esp_set_offset(struct scsi_target *target, int offset)
2709 {
2710         struct Scsi_Host *host = dev_to_shost(target->dev.parent);
2711         struct esp *esp = shost_priv(host);
2712         struct esp_target_data *tp = &esp->target[target->id];
2713
2714         if (esp->flags & ESP_FLAG_DISABLE_SYNC)
2715                 tp->nego_goal_offset = 0;
2716         else
2717                 tp->nego_goal_offset = offset;
2718         tp->flags |= ESP_TGT_CHECK_NEGO;
2719 }
2720
2721 static void esp_set_period(struct scsi_target *target, int period)
2722 {
2723         struct Scsi_Host *host = dev_to_shost(target->dev.parent);
2724         struct esp *esp = shost_priv(host);
2725         struct esp_target_data *tp = &esp->target[target->id];
2726
2727         tp->nego_goal_period = period;
2728         tp->flags |= ESP_TGT_CHECK_NEGO;
2729 }
2730
2731 static void esp_set_width(struct scsi_target *target, int width)
2732 {
2733         struct Scsi_Host *host = dev_to_shost(target->dev.parent);
2734         struct esp *esp = shost_priv(host);
2735         struct esp_target_data *tp = &esp->target[target->id];
2736
2737         tp->nego_goal_width = (width ? 1 : 0);
2738         tp->flags |= ESP_TGT_CHECK_NEGO;
2739 }
2740
2741 static struct spi_function_template esp_transport_ops = {
2742         .set_offset             = esp_set_offset,
2743         .show_offset            = 1,
2744         .set_period             = esp_set_period,
2745         .show_period            = 1,
2746         .set_width              = esp_set_width,
2747         .show_width             = 1,
2748         .get_signalling         = esp_get_signalling,
2749 };
2750
2751 static int __init esp_init(void)
2752 {
2753         BUILD_BUG_ON(sizeof(struct scsi_pointer) <
2754                      sizeof(struct esp_cmd_priv));
2755
2756         esp_transport_template = spi_attach_transport(&esp_transport_ops);
2757         if (!esp_transport_template)
2758                 return -ENODEV;
2759
2760         return 0;
2761 }
2762
2763 static void __exit esp_exit(void)
2764 {
2765         spi_release_transport(esp_transport_template);
2766 }
2767
2768 MODULE_DESCRIPTION("ESP SCSI driver core");
2769 MODULE_AUTHOR("David S. Miller (davem@davemloft.net)");
2770 MODULE_LICENSE("GPL");
2771 MODULE_VERSION(DRV_VERSION);
2772
2773 module_param(esp_bus_reset_settle, int, 0);
2774 MODULE_PARM_DESC(esp_bus_reset_settle,
2775                  "ESP scsi bus reset delay in seconds");
2776
2777 module_param(esp_debug, int, 0);
2778 MODULE_PARM_DESC(esp_debug,
2779 "ESP bitmapped debugging message enable value:\n"
2780 "       0x00000001      Log interrupt events\n"
2781 "       0x00000002      Log scsi commands\n"
2782 "       0x00000004      Log resets\n"
2783 "       0x00000008      Log message in events\n"
2784 "       0x00000010      Log message out events\n"
2785 "       0x00000020      Log command completion\n"
2786 "       0x00000040      Log disconnects\n"
2787 "       0x00000080      Log data start\n"
2788 "       0x00000100      Log data done\n"
2789 "       0x00000200      Log reconnects\n"
2790 "       0x00000400      Log auto-sense data\n"
2791 );
2792
2793 module_init(esp_init);
2794 module_exit(esp_exit);
2795
2796 #ifdef CONFIG_SCSI_ESP_PIO
2797 static inline unsigned int esp_wait_for_fifo(struct esp *esp)
2798 {
2799         int i = 500000;
2800
2801         do {
2802                 unsigned int fbytes = esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES;
2803
2804                 if (fbytes)
2805                         return fbytes;
2806
2807                 udelay(1);
2808         } while (--i);
2809
2810         shost_printk(KERN_ERR, esp->host, "FIFO is empty. sreg [%02x]\n",
2811                      esp_read8(ESP_STATUS));
2812         return 0;
2813 }
2814
2815 static inline int esp_wait_for_intr(struct esp *esp)
2816 {
2817         int i = 500000;
2818
2819         do {
2820                 esp->sreg = esp_read8(ESP_STATUS);
2821                 if (esp->sreg & ESP_STAT_INTR)
2822                         return 0;
2823
2824                 udelay(1);
2825         } while (--i);
2826
2827         shost_printk(KERN_ERR, esp->host, "IRQ timeout. sreg [%02x]\n",
2828                      esp->sreg);
2829         return 1;
2830 }
2831
2832 #define ESP_FIFO_SIZE 16
2833
2834 void esp_send_pio_cmd(struct esp *esp, u32 addr, u32 esp_count,
2835                       u32 dma_count, int write, u8 cmd)
2836 {
2837         u8 phase = esp->sreg & ESP_STAT_PMASK;
2838
2839         cmd &= ~ESP_CMD_DMA;
2840         esp->send_cmd_error = 0;
2841
2842         if (write) {
2843                 u8 *dst = (u8 *)addr;
2844                 u8 mask = ~(phase == ESP_MIP ? ESP_INTR_FDONE : ESP_INTR_BSERV);
2845
2846                 scsi_esp_cmd(esp, cmd);
2847
2848                 while (1) {
2849                         if (!esp_wait_for_fifo(esp))
2850                                 break;
2851
2852                         *dst++ = readb(esp->fifo_reg);
2853                         --esp_count;
2854
2855                         if (!esp_count)
2856                                 break;
2857
2858                         if (esp_wait_for_intr(esp)) {
2859                                 esp->send_cmd_error = 1;
2860                                 break;
2861                         }
2862
2863                         if ((esp->sreg & ESP_STAT_PMASK) != phase)
2864                                 break;
2865
2866                         esp->ireg = esp_read8(ESP_INTRPT);
2867                         if (esp->ireg & mask) {
2868                                 esp->send_cmd_error = 1;
2869                                 break;
2870                         }
2871
2872                         if (phase == ESP_MIP)
2873                                 esp_write8(ESP_CMD_MOK, ESP_CMD);
2874
2875                         esp_write8(ESP_CMD_TI, ESP_CMD);
2876                 }
2877         } else {
2878                 unsigned int n = ESP_FIFO_SIZE;
2879                 u8 *src = (u8 *)addr;
2880
2881                 scsi_esp_cmd(esp, ESP_CMD_FLUSH);
2882
2883                 if (n > esp_count)
2884                         n = esp_count;
2885                 writesb(esp->fifo_reg, src, n);
2886                 src += n;
2887                 esp_count -= n;
2888
2889                 scsi_esp_cmd(esp, cmd);
2890
2891                 while (esp_count) {
2892                         if (esp_wait_for_intr(esp)) {
2893                                 esp->send_cmd_error = 1;
2894                                 break;
2895                         }
2896
2897                         if ((esp->sreg & ESP_STAT_PMASK) != phase)
2898                                 break;
2899
2900                         esp->ireg = esp_read8(ESP_INTRPT);
2901                         if (esp->ireg & ~ESP_INTR_BSERV) {
2902                                 esp->send_cmd_error = 1;
2903                                 break;
2904                         }
2905
2906                         n = ESP_FIFO_SIZE -
2907                             (esp_read8(ESP_FFLAGS) & ESP_FF_FBYTES);
2908
2909                         if (n > esp_count)
2910                                 n = esp_count;
2911                         writesb(esp->fifo_reg, src, n);
2912                         src += n;
2913                         esp_count -= n;
2914
2915                         esp_write8(ESP_CMD_TI, ESP_CMD);
2916                 }
2917         }
2918
2919         esp->send_cmd_residual = esp_count;
2920 }
2921 EXPORT_SYMBOL(esp_send_pio_cmd);
2922 #endif