drivers/scsi/mesh.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * SCSI low-level driver for the MESH (Macintosh Enhanced SCSI Hardware)
   4  * bus adaptor found on Power Macintosh computers.
   5  * We assume the MESH is connected to a DBDMA (descriptor-based DMA)
   6  * controller.
   7  *
   8  * Paul Mackerras, August 1996.
   9  * Copyright (C) 1996 Paul Mackerras.
  10  *
  11  * Apr. 21 2002  - BenH         Rework bus reset code for new error handler
  12  *                              Add delay after initial bus reset
  13  *                              Add module parameters
  14  *
  15  * Sep. 27 2003  - BenH         Move to new driver model, fix some write posting
  16  *                              issues
  17  * To do:
  18  * - handle aborts correctly
  19  * - retry arbitration if lost (unless higher levels do this for us)
  20  * - power down the chip when no device is detected
  21  */
  22 #include <linux/module.h>
  23 #include <linux/kernel.h>
  24 #include <linux/delay.h>
  25 #include <linux/types.h>
  26 #include <linux/string.h>
  27 #include <linux/blkdev.h>
  28 #include <linux/proc_fs.h>
  29 #include <linux/stat.h>
  30 #include <linux/interrupt.h>
  31 #include <linux/reboot.h>
  32 #include <linux/spinlock.h>
  33 #include <linux/pci.h>
  34 #include <linux/pgtable.h>
  35 #include <asm/dbdma.h>
  36 #include <asm/io.h>
  37 #include <asm/prom.h>
  38 #include <asm/irq.h>
  39 #include <asm/hydra.h>
  40 #include <asm/processor.h>
  41 #include <asm/setup.h>
  42 #include <asm/pmac_feature.h>
  43 #include <asm/macio.h>
  44
  45 #include <scsi/scsi.h>
  46 #include <scsi/scsi_cmnd.h>
  47 #include <scsi/scsi_device.h>
  48 #include <scsi/scsi_host.h>
  49
  50 #include "mesh.h"
  51
  52 #if 1
  53 #undef KERN_DEBUG
  54 #define KERN_DEBUG KERN_WARNING
  55 #endif
  56
  57 MODULE_AUTHOR("Paul Mackerras <paulus@samba.org>");
  58 MODULE_DESCRIPTION("PowerMac MESH SCSI driver");
  59 MODULE_LICENSE("GPL");
  60
  61 static int sync_rate = CONFIG_SCSI_MESH_SYNC_RATE;
  62 static int sync_targets = 0xff;
  63 static int resel_targets = 0xff;
  64 static int debug_targets = 0;   /* print debug for these targets */
  65 static int init_reset_delay = CONFIG_SCSI_MESH_RESET_DELAY_MS;
  66
  67 module_param(sync_rate, int, 0);
  68 MODULE_PARM_DESC(sync_rate, "Synchronous rate (0..10, 0=async)");
  69 module_param(sync_targets, int, 0);
  70 MODULE_PARM_DESC(sync_targets, "Bitmask of targets allowed to set synchronous");
  71 module_param(resel_targets, int, 0);
  72 MODULE_PARM_DESC(resel_targets, "Bitmask of targets allowed to set disconnect");
  73 module_param(debug_targets, int, 0644);
  74 MODULE_PARM_DESC(debug_targets, "Bitmask of debugged targets");
  75 module_param(init_reset_delay, int, 0);
  76 MODULE_PARM_DESC(init_reset_delay, "Initial bus reset delay (0=no reset)");
  77
  78 static int mesh_sync_period = 100;
  79 static int mesh_sync_offset = 0;
  80 static unsigned char use_active_neg = 0;  /* bit mask for SEQ_ACTIVE_NEG if used */
  81
  82 #define ALLOW_SYNC(tgt)         ((sync_targets >> (tgt)) & 1)
  83 #define ALLOW_RESEL(tgt)        ((resel_targets >> (tgt)) & 1)
  84 #define ALLOW_DEBUG(tgt)        ((debug_targets >> (tgt)) & 1)
  85 #define DEBUG_TARGET(cmd)       ((cmd) && ALLOW_DEBUG((cmd)->device->id))
  86
  87 #undef MESH_DBG
  88 #define N_DBG_LOG       50
  89 #define N_DBG_SLOG      20
  90 #define NUM_DBG_EVENTS  13
  91 #undef  DBG_USE_TB              /* bombs on 601 */
  92
  93 struct dbglog {
  94         char    *fmt;
  95         u32     tb;
  96         u8      phase;
  97         u8      bs0;
  98         u8      bs1;
  99         u8      tgt;
 100         int     d;
 101 };
 102
 103 enum mesh_phase {
 104         idle,
 105         arbitrating,
 106         selecting,
 107         commanding,
 108         dataing,
 109         statusing,
 110         busfreeing,
 111         disconnecting,
 112         reselecting,
 113         sleeping
 114 };
 115
 116 enum msg_phase {
 117         msg_none,
 118         msg_out,
 119         msg_out_xxx,
 120         msg_out_last,
 121         msg_in,
 122         msg_in_bad,
 123 };
 124
 125 enum sdtr_phase {
 126         do_sdtr,
 127         sdtr_sent,
 128         sdtr_done
 129 };
 130
 131 struct mesh_target {
 132         enum sdtr_phase sdtr_state;
 133         int     sync_params;
 134         int     data_goes_out;          /* guess as to data direction */
 135         struct scsi_cmnd *current_req;
 136         u32     saved_ptr;
 137 #ifdef MESH_DBG
 138         int     log_ix;
 139         int     n_log;
 140         struct dbglog log[N_DBG_LOG];
 141 #endif
 142 };
 143
 144 struct mesh_state {
 145         volatile struct mesh_regs __iomem *mesh;
 146         int     meshintr;
 147         volatile struct dbdma_regs __iomem *dma;
 148         int     dmaintr;
 149         struct  Scsi_Host *host;
 150         struct  mesh_state *next;
 151         struct scsi_cmnd *request_q;
 152         struct scsi_cmnd *request_qtail;
 153         enum mesh_phase phase;          /* what we're currently trying to do */
 154         enum msg_phase msgphase;
 155         int     conn_tgt;               /* target we're connected to */
 156         struct scsi_cmnd *current_req;          /* req we're currently working on */
 157         int     data_ptr;
 158         int     dma_started;
 159         int     dma_count;
 160         int     stat;
 161         int     aborting;
 162         int     expect_reply;
 163         int     n_msgin;
 164         u8      msgin[16];
 165         int     n_msgout;
 166         int     last_n_msgout;
 167         u8      msgout[16];
 168         struct dbdma_cmd *dma_cmds;     /* space for dbdma commands, aligned */
 169         dma_addr_t dma_cmd_bus;
 170         void    *dma_cmd_space;
 171         int     dma_cmd_size;
 172         int     clk_freq;
 173         struct mesh_target tgts[8];
 174         struct macio_dev *mdev;
 175         struct pci_dev* pdev;
 176 #ifdef MESH_DBG
 177         int     log_ix;
 178         int     n_log;
 179         struct dbglog log[N_DBG_SLOG];
 180 #endif
 181 };
 182
 183 /*
 184  * Driver is too messy, we need a few prototypes...
 185  */
 186 static void mesh_done(struct mesh_state *ms, int start_next);
 187 static void mesh_interrupt(struct mesh_state *ms);
 188 static void cmd_complete(struct mesh_state *ms);
 189 static void set_dma_cmds(struct mesh_state *ms, struct scsi_cmnd *cmd);
 190 static void halt_dma(struct mesh_state *ms);
 191 static void phase_mismatch(struct mesh_state *ms);
 192
 193
 194 /*
 195  * Some debugging & logging routines
 196  */
 197
 198 #ifdef MESH_DBG
 199
 200 static inline u32 readtb(void)
 201 {
 202         u32 tb;
 203
 204 #ifdef DBG_USE_TB
 205         /* Beware: if you enable this, it will crash on 601s. */
 206         asm ("mftb %0" : "=r" (tb) : );
 207 #else
 208         tb = 0;
 209 #endif
 210         return tb;
 211 }
 212
 213 static void dlog(struct mesh_state *ms, char *fmt, int a)
 214 {
 215         struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
 216         struct dbglog *tlp, *slp;
 217
 218         tlp = &tp->log[tp->log_ix];
 219         slp = &ms->log[ms->log_ix];
 220         tlp->fmt = fmt;
 221         tlp->tb = readtb();
 222         tlp->phase = (ms->msgphase << 4) + ms->phase;
 223         tlp->bs0 = ms->mesh->bus_status0;
 224         tlp->bs1 = ms->mesh->bus_status1;
 225         tlp->tgt = ms->conn_tgt;
 226         tlp->d = a;
 227         *slp = *tlp;
 228         if (++tp->log_ix >= N_DBG_LOG)
 229                 tp->log_ix = 0;
 230         if (tp->n_log < N_DBG_LOG)
 231                 ++tp->n_log;
 232         if (++ms->log_ix >= N_DBG_SLOG)
 233                 ms->log_ix = 0;
 234         if (ms->n_log < N_DBG_SLOG)
 235                 ++ms->n_log;
 236 }
 237
 238 static void dumplog(struct mesh_state *ms, int t)
 239 {
 240         struct mesh_target *tp = &ms->tgts[t];
 241         struct dbglog *lp;
 242         int i;
 243
 244         if (tp->n_log == 0)
 245                 return;
 246         i = tp->log_ix - tp->n_log;
 247         if (i < 0)
 248                 i += N_DBG_LOG;
 249         tp->n_log = 0;
 250         do {
 251                 lp = &tp->log[i];
 252                 printk(KERN_DEBUG "mesh log %d: bs=%.2x%.2x ph=%.2x ",
 253                        t, lp->bs1, lp->bs0, lp->phase);
 254 #ifdef DBG_USE_TB
 255                 printk("tb=%10u ", lp->tb);
 256 #endif
 257                 printk(lp->fmt, lp->d);
 258                 printk("\n");
 259                 if (++i >= N_DBG_LOG)
 260                         i = 0;
 261         } while (i != tp->log_ix);
 262 }
 263
 264 static void dumpslog(struct mesh_state *ms)
 265 {
 266         struct dbglog *lp;
 267         int i;
 268
 269         if (ms->n_log == 0)
 270                 return;
 271         i = ms->log_ix - ms->n_log;
 272         if (i < 0)
 273                 i += N_DBG_SLOG;
 274         ms->n_log = 0;
 275         do {
 276                 lp = &ms->log[i];
 277                 printk(KERN_DEBUG "mesh log: bs=%.2x%.2x ph=%.2x t%d ",
 278                        lp->bs1, lp->bs0, lp->phase, lp->tgt);
 279 #ifdef DBG_USE_TB
 280                 printk("tb=%10u ", lp->tb);
 281 #endif
 282                 printk(lp->fmt, lp->d);
 283                 printk("\n");
 284                 if (++i >= N_DBG_SLOG)
 285                         i = 0;
 286         } while (i != ms->log_ix);
 287 }
 288
 289 #else
 290
 291 static inline void dlog(struct mesh_state *ms, char *fmt, int a)
 292 {}
 293 static inline void dumplog(struct mesh_state *ms, int tgt)
 294 {}
 295 static inline void dumpslog(struct mesh_state *ms)
 296 {}
 297
 298 #endif /* MESH_DBG */
 299
 300 #define MKWORD(a, b, c, d)      (((a) << 24) + ((b) << 16) + ((c) << 8) + (d))
 301
 302 static void
 303 mesh_dump_regs(struct mesh_state *ms)
 304 {
 305         volatile struct mesh_regs __iomem *mr = ms->mesh;
 306         volatile struct dbdma_regs __iomem *md = ms->dma;
 307         int t;
 308         struct mesh_target *tp;
 309
 310         printk(KERN_DEBUG "mesh: state at %p, regs at %p, dma at %p\n",
 311                ms, mr, md);
 312         printk(KERN_DEBUG "    ct=%4x seq=%2x bs=%4x fc=%2x "
 313                "exc=%2x err=%2x im=%2x int=%2x sp=%2x\n",
 314                (mr->count_hi << 8) + mr->count_lo, mr->sequence,
 315                (mr->bus_status1 << 8) + mr->bus_status0, mr->fifo_count,
 316                mr->exception, mr->error, mr->intr_mask, mr->interrupt,
 317                mr->sync_params);
 318         while(in_8(&mr->fifo_count))
 319                 printk(KERN_DEBUG " fifo data=%.2x\n",in_8(&mr->fifo));
 320         printk(KERN_DEBUG "    dma stat=%x cmdptr=%x\n",
 321                in_le32(&md->status), in_le32(&md->cmdptr));
 322         printk(KERN_DEBUG "    phase=%d msgphase=%d conn_tgt=%d data_ptr=%d\n",
 323                ms->phase, ms->msgphase, ms->conn_tgt, ms->data_ptr);
 324         printk(KERN_DEBUG "    dma_st=%d dma_ct=%d n_msgout=%d\n",
 325                ms->dma_started, ms->dma_count, ms->n_msgout);
 326         for (t = 0; t < 8; ++t) {
 327                 tp = &ms->tgts[t];
 328                 if (tp->current_req == NULL)
 329                         continue;
 330                 printk(KERN_DEBUG "    target %d: req=%p goes_out=%d saved_ptr=%d\n",
 331                        t, tp->current_req, tp->data_goes_out, tp->saved_ptr);
 332         }
 333 }
 334
 335
 336 /*
 337  * Flush write buffers on the bus path to the mesh
 338  */
 339 static inline void mesh_flush_io(volatile struct mesh_regs __iomem *mr)
 340 {
 341         (void)in_8(&mr->mesh_id);
 342 }
 343
 344
 345 /* Called with  meshinterrupt disabled, initialize the chipset
 346  * and eventually do the initial bus reset. The lock must not be
 347  * held since we can schedule.
 348  */
 349 static void mesh_init(struct mesh_state *ms)
 350 {
 351         volatile struct mesh_regs __iomem *mr = ms->mesh;
 352         volatile struct dbdma_regs __iomem *md = ms->dma;
 353
 354         mesh_flush_io(mr);
 355         udelay(100);
 356
 357         /* Reset controller */
 358         out_le32(&md->control, (RUN|PAUSE|FLUSH|WAKE) << 16);   /* stop dma */
 359         out_8(&mr->exception, 0xff);    /* clear all exception bits */
 360         out_8(&mr->error, 0xff);        /* clear all error bits */
 361         out_8(&mr->sequence, SEQ_RESETMESH);
 362         mesh_flush_io(mr);
 363         udelay(10);
 364         out_8(&mr->intr_mask, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
 365         out_8(&mr->source_id, ms->host->this_id);
 366         out_8(&mr->sel_timeout, 25);    /* 250ms */
 367         out_8(&mr->sync_params, ASYNC_PARAMS);
 368
 369         if (init_reset_delay) {
 370                 printk(KERN_INFO "mesh: performing initial bus reset...\n");
 371
 372                 /* Reset bus */
 373                 out_8(&mr->bus_status1, BS1_RST);       /* assert RST */
 374                 mesh_flush_io(mr);
 375                 udelay(30);                     /* leave it on for >= 25us */
 376                 out_8(&mr->bus_status1, 0);     /* negate RST */
 377                 mesh_flush_io(mr);
 378
 379                 /* Wait for bus to come back */
 380                 msleep(init_reset_delay);
 381         }
 382
 383         /* Reconfigure controller */
 384         out_8(&mr->interrupt, 0xff);    /* clear all interrupt bits */
 385         out_8(&mr->sequence, SEQ_FLUSHFIFO);
 386         mesh_flush_io(mr);
 387         udelay(1);
 388         out_8(&mr->sync_params, ASYNC_PARAMS);
 389         out_8(&mr->sequence, SEQ_ENBRESEL);
 390
 391         ms->phase = idle;
 392         ms->msgphase = msg_none;
 393 }
 394
 395
 396 static void mesh_start_cmd(struct mesh_state *ms, struct scsi_cmnd *cmd)
 397 {
 398         volatile struct mesh_regs __iomem *mr = ms->mesh;
 399         int t, id;
 400
 401         id = cmd->device->id;
 402         ms->current_req = cmd;
 403         ms->tgts[id].data_goes_out = cmd->sc_data_direction == DMA_TO_DEVICE;
 404         ms->tgts[id].current_req = cmd;
 405
 406 #if 1
 407         if (DEBUG_TARGET(cmd)) {
 408                 int i;
 409                 printk(KERN_DEBUG "mesh_start: %p tgt=%d cmd=", cmd, id);
 410                 for (i = 0; i < cmd->cmd_len; ++i)
 411                         printk(" %x", cmd->cmnd[i]);
 412                 printk(" use_sg=%d buffer=%p bufflen=%u\n",
 413                        scsi_sg_count(cmd), scsi_sglist(cmd), scsi_bufflen(cmd));
 414         }
 415 #endif
 416         if (ms->dma_started)
 417                 panic("mesh: double DMA start !\n");
 418
 419         ms->phase = arbitrating;
 420         ms->msgphase = msg_none;
 421         ms->data_ptr = 0;
 422         ms->dma_started = 0;
 423         ms->n_msgout = 0;
 424         ms->last_n_msgout = 0;
 425         ms->expect_reply = 0;
 426         ms->conn_tgt = id;
 427         ms->tgts[id].saved_ptr = 0;
 428         ms->stat = DID_OK;
 429         ms->aborting = 0;
 430 #ifdef MESH_DBG
 431         ms->tgts[id].n_log = 0;
 432         dlog(ms, "start cmd=%x", (int) cmd);
 433 #endif
 434
 435         /* Off we go */
 436         dlog(ms, "about to arb, intr/exc/err/fc=%.8x",
 437              MKWORD(mr->interrupt, mr->exception, mr->error, mr->fifo_count));
 438         out_8(&mr->interrupt, INT_CMDDONE);
 439         out_8(&mr->sequence, SEQ_ENBRESEL);
 440         mesh_flush_io(mr);
 441         udelay(1);
 442
 443         if (in_8(&mr->bus_status1) & (BS1_BSY | BS1_SEL)) {
 444                 /*
 445                  * Some other device has the bus or is arbitrating for it -
 446                  * probably a target which is about to reselect us.
 447                  */
 448                 dlog(ms, "busy b4 arb, intr/exc/err/fc=%.8x",
 449                      MKWORD(mr->interrupt, mr->exception,
 450                             mr->error, mr->fifo_count));
 451                 for (t = 100; t > 0; --t) {
 452                         if ((in_8(&mr->bus_status1) & (BS1_BSY | BS1_SEL)) == 0)
 453                                 break;
 454                         if (in_8(&mr->interrupt) != 0) {
 455                                 dlog(ms, "intr b4 arb, intr/exc/err/fc=%.8x",
 456                                      MKWORD(mr->interrupt, mr->exception,
 457                                             mr->error, mr->fifo_count));
 458                                 mesh_interrupt(ms);
 459                                 if (ms->phase != arbitrating)
 460                                         return;
 461                         }
 462                         udelay(1);
 463                 }
 464                 if (in_8(&mr->bus_status1) & (BS1_BSY | BS1_SEL)) {
 465                         /* XXX should try again in a little while */
 466                         ms->stat = DID_BUS_BUSY;
 467                         ms->phase = idle;
 468                         mesh_done(ms, 0);
 469                         return;
 470                 }
 471         }
 472
 473         /*
 474          * Apparently the mesh has a bug where it will assert both its
 475          * own bit and the target's bit on the bus during arbitration.
 476          */
 477         out_8(&mr->dest_id, mr->source_id);
 478
 479         /*
 480          * There appears to be a race with reselection sometimes,
 481          * where a target reselects us just as we issue the
 482          * arbitrate command.  It seems that then the arbitrate
 483          * command just hangs waiting for the bus to be free
 484          * without giving us a reselection exception.
 485          * The only way I have found to get it to respond correctly
 486          * is this: disable reselection before issuing the arbitrate
 487          * command, then after issuing it, if it looks like a target
 488          * is trying to reselect us, reset the mesh and then enable
 489          * reselection.
 490          */
 491         out_8(&mr->sequence, SEQ_DISRESEL);
 492         if (in_8(&mr->interrupt) != 0) {
 493                 dlog(ms, "intr after disresel, intr/exc/err/fc=%.8x",
 494                      MKWORD(mr->interrupt, mr->exception,
 495                             mr->error, mr->fifo_count));
 496                 mesh_interrupt(ms);
 497                 if (ms->phase != arbitrating)
 498                         return;
 499                 dlog(ms, "after intr after disresel, intr/exc/err/fc=%.8x",
 500                      MKWORD(mr->interrupt, mr->exception,
 501                             mr->error, mr->fifo_count));
 502         }
 503
 504         out_8(&mr->sequence, SEQ_ARBITRATE);
 505
 506         for (t = 230; t > 0; --t) {
 507                 if (in_8(&mr->interrupt) != 0)
 508                         break;
 509                 udelay(1);
 510         }
 511         dlog(ms, "after arb, intr/exc/err/fc=%.8x",
 512              MKWORD(mr->interrupt, mr->exception, mr->error, mr->fifo_count));
 513         if (in_8(&mr->interrupt) == 0 && (in_8(&mr->bus_status1) & BS1_SEL)
 514             && (in_8(&mr->bus_status0) & BS0_IO)) {
 515                 /* looks like a reselection - try resetting the mesh */
 516                 dlog(ms, "resel? after arb, intr/exc/err/fc=%.8x",
 517                      MKWORD(mr->interrupt, mr->exception, mr->error, mr->fifo_count));
 518                 out_8(&mr->sequence, SEQ_RESETMESH);
 519                 mesh_flush_io(mr);
 520                 udelay(10);
 521                 out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
 522                 out_8(&mr->intr_mask, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
 523                 out_8(&mr->sequence, SEQ_ENBRESEL);
 524                 mesh_flush_io(mr);
 525                 for (t = 10; t > 0 && in_8(&mr->interrupt) == 0; --t)
 526                         udelay(1);
 527                 dlog(ms, "tried reset after arb, intr/exc/err/fc=%.8x",
 528                      MKWORD(mr->interrupt, mr->exception, mr->error, mr->fifo_count));
 529 #ifndef MESH_MULTIPLE_HOSTS
 530                 if (in_8(&mr->interrupt) == 0 && (in_8(&mr->bus_status1) & BS1_SEL)
 531                     && (in_8(&mr->bus_status0) & BS0_IO)) {
 532                         printk(KERN_ERR "mesh: controller not responding"
 533                                " to reselection!\n");
 534                         /*
 535                          * If this is a target reselecting us, and the
 536                          * mesh isn't responding, the higher levels of
 537                          * the scsi code will eventually time out and
 538                          * reset the bus.
 539                          */
 540                 }
 541 #endif
 542         }
 543 }
 544
 545 /*
 546  * Start the next command for a MESH.
 547  * Should be called with interrupts disabled.
 548  */
 549 static void mesh_start(struct mesh_state *ms)
 550 {
 551         struct scsi_cmnd *cmd, *prev, *next;
 552
 553         if (ms->phase != idle || ms->current_req != NULL) {
 554                 printk(KERN_ERR "inappropriate mesh_start (phase=%d, ms=%p)",
 555                        ms->phase, ms);
 556                 return;
 557         }
 558
 559         while (ms->phase == idle) {
 560                 prev = NULL;
 561                 for (cmd = ms->request_q; ; cmd = (struct scsi_cmnd *) cmd->host_scribble) {
 562                         if (cmd == NULL)
 563                                 return;
 564                         if (ms->tgts[cmd->device->id].current_req == NULL)
 565                                 break;
 566                         prev = cmd;
 567                 }
 568                 next = (struct scsi_cmnd *) cmd->host_scribble;
 569                 if (prev == NULL)
 570                         ms->request_q = next;
 571                 else
 572                         prev->host_scribble = (void *) next;
 573                 if (next == NULL)
 574                         ms->request_qtail = prev;
 575
 576                 mesh_start_cmd(ms, cmd);
 577         }
 578 }
 579
 580 static void mesh_done(struct mesh_state *ms, int start_next)
 581 {
 582         struct scsi_cmnd *cmd;
 583         struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
 584
 585         cmd = ms->current_req;
 586         ms->current_req = NULL;
 587         tp->current_req = NULL;
 588         if (cmd) {
 589                 struct mesh_cmd_priv *mcmd = mesh_priv(cmd);
 590
 591                 set_host_byte(cmd, ms->stat);
 592                 set_status_byte(cmd, mcmd->status);
 593                 if (ms->stat == DID_OK)
 594                         scsi_msg_to_host_byte(cmd, mcmd->message);
 595                 if (DEBUG_TARGET(cmd)) {
 596                         printk(KERN_DEBUG "mesh_done: result = %x, data_ptr=%d, buflen=%d\n",
 597                                cmd->result, ms->data_ptr, scsi_bufflen(cmd));
 598 #if 0
 599                         /* needs to use sg? */
 600                         if ((cmd->cmnd[0] == 0 || cmd->cmnd[0] == 0x12 || cmd->cmnd[0] == 3)
 601                             && cmd->request_buffer != 0) {
 602                                 unsigned char *b = cmd->request_buffer;
 603                                 printk(KERN_DEBUG "buffer = %x %x %x %x %x %x %x %x\n",
 604                                        b[0], b[1], b[2], b[3], b[4], b[5], b[6], b[7]);
 605                         }
 606 #endif
 607                 }
 608                 mcmd->this_residual -= ms->data_ptr;
 609                 scsi_done(cmd);
 610         }
 611         if (start_next) {
 612                 out_8(&ms->mesh->sequence, SEQ_ENBRESEL);
 613                 mesh_flush_io(ms->mesh);
 614                 udelay(1);
 615                 ms->phase = idle;
 616                 mesh_start(ms);
 617         }
 618 }
 619
 620 static inline void add_sdtr_msg(struct mesh_state *ms)
 621 {
 622         int i = ms->n_msgout;
 623
 624         ms->msgout[i] = EXTENDED_MESSAGE;
 625         ms->msgout[i+1] = 3;
 626         ms->msgout[i+2] = EXTENDED_SDTR;
 627         ms->msgout[i+3] = mesh_sync_period/4;
 628         ms->msgout[i+4] = (ALLOW_SYNC(ms->conn_tgt)? mesh_sync_offset: 0);
 629         ms->n_msgout = i + 5;
 630 }
 631
 632 static void set_sdtr(struct mesh_state *ms, int period, int offset)
 633 {
 634         struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
 635         volatile struct mesh_regs __iomem *mr = ms->mesh;
 636         int v, tr;
 637
 638         tp->sdtr_state = sdtr_done;
 639         if (offset == 0) {
 640                 /* asynchronous */
 641                 if (SYNC_OFF(tp->sync_params))
 642                         printk(KERN_INFO "mesh: target %d now asynchronous\n",
 643                                ms->conn_tgt);
 644                 tp->sync_params = ASYNC_PARAMS;
 645                 out_8(&mr->sync_params, ASYNC_PARAMS);
 646                 return;
 647         }
 648         /*
 649          * We need to compute ceil(clk_freq * period / 500e6) - 2
 650          * without incurring overflow.
 651          */
 652         v = (ms->clk_freq / 5000) * period;
 653         if (v <= 250000) {
 654                 /* special case: sync_period == 5 * clk_period */
 655                 v = 0;
 656                 /* units of tr are 100kB/s */
 657                 tr = (ms->clk_freq + 250000) / 500000;
 658         } else {
 659                 /* sync_period == (v + 2) * 2 * clk_period */
 660                 v = (v + 99999) / 100000 - 2;
 661                 if (v > 15)
 662                         v = 15; /* oops */
 663                 tr = ((ms->clk_freq / (v + 2)) + 199999) / 200000;
 664         }
 665         if (offset > 15)
 666                 offset = 15;    /* can't happen */
 667         tp->sync_params = SYNC_PARAMS(offset, v);
 668         out_8(&mr->sync_params, tp->sync_params);
 669         printk(KERN_INFO "mesh: target %d synchronous at %d.%d MB/s\n",
 670                ms->conn_tgt, tr/10, tr%10);
 671 }
 672
 673 static void start_phase(struct mesh_state *ms)
 674 {
 675         int i, seq, nb;
 676         volatile struct mesh_regs __iomem *mr = ms->mesh;
 677         volatile struct dbdma_regs __iomem *md = ms->dma;
 678         struct scsi_cmnd *cmd = ms->current_req;
 679         struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
 680
 681         dlog(ms, "start_phase nmo/exc/fc/seq = %.8x",
 682              MKWORD(ms->n_msgout, mr->exception, mr->fifo_count, mr->sequence));
 683         out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
 684         seq = use_active_neg + (ms->n_msgout? SEQ_ATN: 0);
 685         switch (ms->msgphase) {
 686         case msg_none:
 687                 break;
 688
 689         case msg_in:
 690                 out_8(&mr->count_hi, 0);
 691                 out_8(&mr->count_lo, 1);
 692                 out_8(&mr->sequence, SEQ_MSGIN + seq);
 693                 ms->n_msgin = 0;
 694                 return;
 695
 696         case msg_out:
 697                 /*
 698                  * To make sure ATN drops before we assert ACK for
 699                  * the last byte of the message, we have to do the
 700                  * last byte specially.
 701                  */
 702                 if (ms->n_msgout <= 0) {
 703                         printk(KERN_ERR "mesh: msg_out but n_msgout=%d\n",
 704                                ms->n_msgout);
 705                         mesh_dump_regs(ms);
 706                         ms->msgphase = msg_none;
 707                         break;
 708                 }
 709                 if (ALLOW_DEBUG(ms->conn_tgt)) {
 710                         printk(KERN_DEBUG "mesh: sending %d msg bytes:",
 711                                ms->n_msgout);
 712                         for (i = 0; i < ms->n_msgout; ++i)
 713                                 printk(" %x", ms->msgout[i]);
 714                         printk("\n");
 715                 }
 716                 dlog(ms, "msgout msg=%.8x", MKWORD(ms->n_msgout, ms->msgout[0],
 717                                                 ms->msgout[1], ms->msgout[2]));
 718                 out_8(&mr->count_hi, 0);
 719                 out_8(&mr->sequence, SEQ_FLUSHFIFO);
 720                 mesh_flush_io(mr);
 721                 udelay(1);
 722                 /*
 723                  * If ATN is not already asserted, we assert it, then
 724                  * issue a SEQ_MSGOUT to get the mesh to drop ACK.
 725                  */
 726                 if ((in_8(&mr->bus_status0) & BS0_ATN) == 0) {
 727                         dlog(ms, "bus0 was %.2x explicitly asserting ATN", mr->bus_status0);
 728                         out_8(&mr->bus_status0, BS0_ATN); /* explicit ATN */
 729                         mesh_flush_io(mr);
 730                         udelay(1);
 731                         out_8(&mr->count_lo, 1);
 732                         out_8(&mr->sequence, SEQ_MSGOUT + seq);
 733                         out_8(&mr->bus_status0, 0); /* release explicit ATN */
 734                         dlog(ms,"hace: after explicit ATN bus0=%.2x",mr->bus_status0);
 735                 }
 736                 if (ms->n_msgout == 1) {
 737                         /*
 738                          * We can't issue the SEQ_MSGOUT without ATN
 739                          * until the target has asserted REQ.  The logic
 740                          * in cmd_complete handles both situations:
 741                          * REQ already asserted or not.
 742                          */
 743                         cmd_complete(ms);
 744                 } else {
 745                         out_8(&mr->count_lo, ms->n_msgout - 1);
 746                         out_8(&mr->sequence, SEQ_MSGOUT + seq);
 747                         for (i = 0; i < ms->n_msgout - 1; ++i)
 748                                 out_8(&mr->fifo, ms->msgout[i]);
 749                 }
 750                 return;
 751
 752         default:
 753                 printk(KERN_ERR "mesh bug: start_phase msgphase=%d\n",
 754                        ms->msgphase);
 755         }
 756
 757         switch (ms->phase) {
 758         case selecting:
 759                 out_8(&mr->dest_id, ms->conn_tgt);
 760                 out_8(&mr->sequence, SEQ_SELECT + SEQ_ATN);
 761                 break;
 762         case commanding:
 763                 out_8(&mr->sync_params, tp->sync_params);
 764                 out_8(&mr->count_hi, 0);
 765                 if (cmd) {
 766                         out_8(&mr->count_lo, cmd->cmd_len);
 767                         out_8(&mr->sequence, SEQ_COMMAND + seq);
 768                         for (i = 0; i < cmd->cmd_len; ++i)
 769                                 out_8(&mr->fifo, cmd->cmnd[i]);
 770                 } else {
 771                         out_8(&mr->count_lo, 6);
 772                         out_8(&mr->sequence, SEQ_COMMAND + seq);
 773                         for (i = 0; i < 6; ++i)
 774                                 out_8(&mr->fifo, 0);
 775                 }
 776                 break;
 777         case dataing:
 778                 /* transfer data, if any */
 779                 if (!ms->dma_started) {
 780                         set_dma_cmds(ms, cmd);
 781                         out_le32(&md->cmdptr, virt_to_phys(ms->dma_cmds));
 782                         out_le32(&md->control, (RUN << 16) | RUN);
 783                         ms->dma_started = 1;
 784                 }
 785                 nb = ms->dma_count;
 786                 if (nb > 0xfff0)
 787                         nb = 0xfff0;
 788                 ms->dma_count -= nb;
 789                 ms->data_ptr += nb;
 790                 out_8(&mr->count_lo, nb);
 791                 out_8(&mr->count_hi, nb >> 8);
 792                 out_8(&mr->sequence, (tp->data_goes_out?
 793                                 SEQ_DATAOUT: SEQ_DATAIN) + SEQ_DMA_MODE + seq);
 794                 break;
 795         case statusing:
 796                 out_8(&mr->count_hi, 0);
 797                 out_8(&mr->count_lo, 1);
 798                 out_8(&mr->sequence, SEQ_STATUS + seq);
 799                 break;
 800         case busfreeing:
 801         case disconnecting:
 802                 out_8(&mr->sequence, SEQ_ENBRESEL);
 803                 mesh_flush_io(mr);
 804                 udelay(1);
 805                 dlog(ms, "enbresel intr/exc/err/fc=%.8x",
 806                      MKWORD(mr->interrupt, mr->exception, mr->error,
 807                             mr->fifo_count));
 808                 out_8(&mr->sequence, SEQ_BUSFREE);
 809                 break;
 810         default:
 811                 printk(KERN_ERR "mesh: start_phase called with phase=%d\n",
 812                        ms->phase);
 813                 dumpslog(ms);
 814         }
 815
 816 }
 817
 818 static inline void get_msgin(struct mesh_state *ms)
 819 {
 820         volatile struct mesh_regs __iomem *mr = ms->mesh;
 821         int i, n;
 822
 823         n = mr->fifo_count;
 824         if (n != 0) {
 825                 i = ms->n_msgin;
 826                 ms->n_msgin = i + n;
 827                 for (; n > 0; --n)
 828                         ms->msgin[i++] = in_8(&mr->fifo);
 829         }
 830 }
 831
 832 static inline int msgin_length(struct mesh_state *ms)
 833 {
 834         int b, n;
 835
 836         n = 1;
 837         if (ms->n_msgin > 0) {
 838                 b = ms->msgin[0];
 839                 if (b == 1) {
 840                         /* extended message */
 841                         n = ms->n_msgin < 2? 2: ms->msgin[1] + 2;
 842                 } else if (0x20 <= b && b <= 0x2f) {
 843                         /* 2-byte message */
 844                         n = 2;
 845                 }
 846         }
 847         return n;
 848 }
 849
 850 static void reselected(struct mesh_state *ms)
 851 {
 852         volatile struct mesh_regs __iomem *mr = ms->mesh;
 853         struct scsi_cmnd *cmd;
 854         struct mesh_target *tp;
 855         int b, t, prev;
 856
 857         switch (ms->phase) {
 858         case idle:
 859                 break;
 860         case arbitrating:
 861                 if ((cmd = ms->current_req) != NULL) {
 862                         /* put the command back on the queue */
 863                         cmd->host_scribble = (void *) ms->request_q;
 864                         if (ms->request_q == NULL)
 865                                 ms->request_qtail = cmd;
 866                         ms->request_q = cmd;
 867                         tp = &ms->tgts[cmd->device->id];
 868                         tp->current_req = NULL;
 869                 }
 870                 break;
 871         case busfreeing:
 872                 ms->phase = reselecting;
 873                 mesh_done(ms, 0);
 874                 break;
 875         case disconnecting:
 876                 break;
 877         default:
 878                 printk(KERN_ERR "mesh: reselected in phase %d/%d tgt %d\n",
 879                        ms->msgphase, ms->phase, ms->conn_tgt);
 880                 dumplog(ms, ms->conn_tgt);
 881                 dumpslog(ms);
 882         }
 883
 884         if (ms->dma_started) {
 885                 printk(KERN_ERR "mesh: reselected with DMA started !\n");
 886                 halt_dma(ms);
 887         }
 888         ms->current_req = NULL;
 889         ms->phase = dataing;
 890         ms->msgphase = msg_in;
 891         ms->n_msgout = 0;
 892         ms->last_n_msgout = 0;
 893         prev = ms->conn_tgt;
 894
 895         /*
 896          * We seem to get abortive reselections sometimes.
 897          */
 898         while ((in_8(&mr->bus_status1) & BS1_BSY) == 0) {
 899                 static int mesh_aborted_resels;
 900                 mesh_aborted_resels++;
 901                 out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
 902                 mesh_flush_io(mr);
 903                 udelay(1);
 904                 out_8(&mr->sequence, SEQ_ENBRESEL);
 905                 mesh_flush_io(mr);
 906                 udelay(5);
 907                 dlog(ms, "extra resel err/exc/fc = %.6x",
 908                      MKWORD(0, mr->error, mr->exception, mr->fifo_count));
 909         }
 910         out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
 911         mesh_flush_io(mr);
 912         udelay(1);
 913         out_8(&mr->sequence, SEQ_ENBRESEL);
 914         mesh_flush_io(mr);
 915         udelay(1);
 916         out_8(&mr->sync_params, ASYNC_PARAMS);
 917
 918         /*
 919          * Find out who reselected us.
 920          */
 921         if (in_8(&mr->fifo_count) == 0) {
 922                 printk(KERN_ERR "mesh: reselection but nothing in fifo?\n");
 923                 ms->conn_tgt = ms->host->this_id;
 924                 goto bogus;
 925         }
 926         /* get the last byte in the fifo */
 927         do {
 928                 b = in_8(&mr->fifo);
 929                 dlog(ms, "reseldata %x", b);
 930         } while (in_8(&mr->fifo_count));
 931         for (t = 0; t < 8; ++t)
 932                 if ((b & (1 << t)) != 0 && t != ms->host->this_id)
 933                         break;
 934         if (b != (1 << t) + (1 << ms->host->this_id)) {
 935                 printk(KERN_ERR "mesh: bad reselection data %x\n", b);
 936                 ms->conn_tgt = ms->host->this_id;
 937                 goto bogus;
 938         }
 939
 940
 941         /*
 942          * Set up to continue with that target's transfer.
 943          */
 944         ms->conn_tgt = t;
 945         tp = &ms->tgts[t];
 946         out_8(&mr->sync_params, tp->sync_params);
 947         if (ALLOW_DEBUG(t)) {
 948                 printk(KERN_DEBUG "mesh: reselected by target %d\n", t);
 949                 printk(KERN_DEBUG "mesh: saved_ptr=%x goes_out=%d cmd=%p\n",
 950                        tp->saved_ptr, tp->data_goes_out, tp->current_req);
 951         }
 952         ms->current_req = tp->current_req;
 953         if (tp->current_req == NULL) {
 954                 printk(KERN_ERR "mesh: reselected by tgt %d but no cmd!\n", t);
 955                 goto bogus;
 956         }
 957         ms->data_ptr = tp->saved_ptr;
 958         dlog(ms, "resel prev tgt=%d", prev);
 959         dlog(ms, "resel err/exc=%.4x", MKWORD(0, 0, mr->error, mr->exception));
 960         start_phase(ms);
 961         return;
 962
 963 bogus:
 964         dumplog(ms, ms->conn_tgt);
 965         dumpslog(ms);
 966         ms->data_ptr = 0;
 967         ms->aborting = 1;
 968         start_phase(ms);
 969 }
 970
 971 static void do_abort(struct mesh_state *ms)
 972 {
 973         ms->msgout[0] = ABORT;
 974         ms->n_msgout = 1;
 975         ms->aborting = 1;
 976         ms->stat = DID_ABORT;
 977         dlog(ms, "abort", 0);
 978 }
 979
 980 static void handle_reset(struct mesh_state *ms)
 981 {
 982         int tgt;
 983         struct mesh_target *tp;
 984         struct scsi_cmnd *cmd;
 985         volatile struct mesh_regs __iomem *mr = ms->mesh;
 986
 987         for (tgt = 0; tgt < 8; ++tgt) {
 988                 tp = &ms->tgts[tgt];
 989                 if ((cmd = tp->current_req) != NULL) {
 990                         set_host_byte(cmd, DID_RESET);
 991                         tp->current_req = NULL;
 992                         scsi_done(cmd);
 993                 }
 994                 ms->tgts[tgt].sdtr_state = do_sdtr;
 995                 ms->tgts[tgt].sync_params = ASYNC_PARAMS;
 996         }
 997         ms->current_req = NULL;
 998         while ((cmd = ms->request_q) != NULL) {
 999                 ms->request_q = (struct scsi_cmnd *) cmd->host_scribble;
1000                 set_host_byte(cmd, DID_RESET);
1001                 scsi_done(cmd);
1002         }
1003         ms->phase = idle;
1004         ms->msgphase = msg_none;
1005         out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
1006         out_8(&mr->sequence, SEQ_FLUSHFIFO);
1007         mesh_flush_io(mr);
1008         udelay(1);
1009         out_8(&mr->sync_params, ASYNC_PARAMS);
1010         out_8(&mr->sequence, SEQ_ENBRESEL);
1011 }
1012
1013 static irqreturn_t do_mesh_interrupt(int irq, void *dev_id)
1014 {
1015         unsigned long flags;
1016         struct mesh_state *ms = dev_id;
1017         struct Scsi_Host *dev = ms->host;
1018
1019         spin_lock_irqsave(dev->host_lock, flags);
1020         mesh_interrupt(ms);
1021         spin_unlock_irqrestore(dev->host_lock, flags);
1022         return IRQ_HANDLED;
1023 }
1024
1025 static void handle_error(struct mesh_state *ms)
1026 {
1027         int err, exc, count;
1028         volatile struct mesh_regs __iomem *mr = ms->mesh;
1029
1030         err = in_8(&mr->error);
1031         exc = in_8(&mr->exception);
1032         out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
1033         dlog(ms, "error err/exc/fc/cl=%.8x",
1034              MKWORD(err, exc, mr->fifo_count, mr->count_lo));
1035         if (err & ERR_SCSIRESET) {
1036                 /* SCSI bus was reset */
1037                 printk(KERN_INFO "mesh: SCSI bus reset detected: "
1038                        "waiting for end...");
1039                 while ((in_8(&mr->bus_status1) & BS1_RST) != 0)
1040                         udelay(1);
1041                 printk("done\n");
1042                 if (ms->dma_started)
1043                         halt_dma(ms);
1044                 handle_reset(ms);
1045                 /* request_q is empty, no point in mesh_start() */
1046                 return;
1047         }
1048         if (err & ERR_UNEXPDISC) {
1049                 /* Unexpected disconnect */
1050                 if (exc & EXC_RESELECTED) {
1051                         reselected(ms);
1052                         return;
1053                 }
1054                 if (!ms->aborting) {
1055                         printk(KERN_WARNING "mesh: target %d aborted\n",
1056                                ms->conn_tgt);
1057                         dumplog(ms, ms->conn_tgt);
1058                         dumpslog(ms);
1059                 }
1060                 out_8(&mr->interrupt, INT_CMDDONE);
1061                 ms->stat = DID_ABORT;
1062                 mesh_done(ms, 1);
1063                 return;
1064         }
1065         if (err & ERR_PARITY) {
1066                 if (ms->msgphase == msg_in) {
1067                         printk(KERN_ERR "mesh: msg parity error, target %d\n",
1068                                ms->conn_tgt);
1069                         ms->msgout[0] = MSG_PARITY_ERROR;
1070                         ms->n_msgout = 1;
1071                         ms->msgphase = msg_in_bad;
1072                         cmd_complete(ms);
1073                         return;
1074                 }
1075                 if (ms->stat == DID_OK) {
1076                         printk(KERN_ERR "mesh: parity error, target %d\n",
1077                                ms->conn_tgt);
1078                         ms->stat = DID_PARITY;
1079                 }
1080                 count = (mr->count_hi << 8) + mr->count_lo;
1081                 if (count == 0) {
1082                         cmd_complete(ms);
1083                 } else {
1084                         /* reissue the data transfer command */
1085                         out_8(&mr->sequence, mr->sequence);
1086                 }
1087                 return;
1088         }
1089         if (err & ERR_SEQERR) {
1090                 if (exc & EXC_RESELECTED) {
1091                         /* This can happen if we issue a command to
1092                            get the bus just after the target reselects us. */
1093                         static int mesh_resel_seqerr;
1094                         mesh_resel_seqerr++;
1095                         reselected(ms);
1096                         return;
1097                 }
1098                 if (exc == EXC_PHASEMM) {
1099                         static int mesh_phasemm_seqerr;
1100                         mesh_phasemm_seqerr++;
1101                         phase_mismatch(ms);
1102                         return;
1103                 }
1104                 printk(KERN_ERR "mesh: sequence error (err=%x exc=%x)\n",
1105                        err, exc);
1106         } else {
1107                 printk(KERN_ERR "mesh: unknown error %x (exc=%x)\n", err, exc);
1108         }
1109         mesh_dump_regs(ms);
1110         dumplog(ms, ms->conn_tgt);
1111         if (ms->phase > selecting && (in_8(&mr->bus_status1) & BS1_BSY)) {
1112                 /* try to do what the target wants */
1113                 do_abort(ms);
1114                 phase_mismatch(ms);
1115                 return;
1116         }
1117         ms->stat = DID_ERROR;
1118         mesh_done(ms, 1);
1119 }
1120
1121 static void handle_exception(struct mesh_state *ms)
1122 {
1123         int exc;
1124         volatile struct mesh_regs __iomem *mr = ms->mesh;
1125
1126         exc = in_8(&mr->exception);
1127         out_8(&mr->interrupt, INT_EXCEPTION | INT_CMDDONE);
1128         if (exc & EXC_RESELECTED) {
1129                 static int mesh_resel_exc;
1130                 mesh_resel_exc++;
1131                 reselected(ms);
1132         } else if (exc == EXC_ARBLOST) {
1133                 printk(KERN_DEBUG "mesh: lost arbitration\n");
1134                 ms->stat = DID_BUS_BUSY;
1135                 mesh_done(ms, 1);
1136         } else if (exc == EXC_SELTO) {
1137                 /* selection timed out */
1138                 ms->stat = DID_BAD_TARGET;
1139                 mesh_done(ms, 1);
1140         } else if (exc == EXC_PHASEMM) {
1141                 /* target wants to do something different:
1142                    find out what it wants and do it. */
1143                 phase_mismatch(ms);
1144         } else {
1145                 printk(KERN_ERR "mesh: can't cope with exception %x\n", exc);
1146                 mesh_dump_regs(ms);
1147                 dumplog(ms, ms->conn_tgt);
1148                 do_abort(ms);
1149                 phase_mismatch(ms);
1150         }
1151 }
1152
1153 static void handle_msgin(struct mesh_state *ms)
1154 {
1155         int i, code;
1156         struct scsi_cmnd *cmd = ms->current_req;
1157         struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
1158
1159         if (ms->n_msgin == 0)
1160                 return;
1161         code = ms->msgin[0];
1162         if (ALLOW_DEBUG(ms->conn_tgt)) {
1163                 printk(KERN_DEBUG "got %d message bytes:", ms->n_msgin);
1164                 for (i = 0; i < ms->n_msgin; ++i)
1165                         printk(" %x", ms->msgin[i]);
1166                 printk("\n");
1167         }
1168         dlog(ms, "msgin msg=%.8x",
1169              MKWORD(ms->n_msgin, code, ms->msgin[1], ms->msgin[2]));
1170
1171         ms->expect_reply = 0;
1172         ms->n_msgout = 0;
1173         if (ms->n_msgin < msgin_length(ms))
1174                 goto reject;
1175         if (cmd)
1176                 mesh_priv(cmd)->message = code;
1177         switch (code) {
1178         case COMMAND_COMPLETE:
1179                 break;
1180         case EXTENDED_MESSAGE:
1181                 switch (ms->msgin[2]) {
1182                 case EXTENDED_MODIFY_DATA_POINTER:
1183                         ms->data_ptr += (ms->msgin[3] << 24) + ms->msgin[6]
1184                                 + (ms->msgin[4] << 16) + (ms->msgin[5] << 8);
1185                         break;
1186                 case EXTENDED_SDTR:
1187                         if (tp->sdtr_state != sdtr_sent) {
1188                                 /* reply with an SDTR */
1189                                 add_sdtr_msg(ms);
1190                                 /* limit period to at least his value,
1191                                    offset to no more than his */
1192                                 if (ms->msgout[3] < ms->msgin[3])
1193                                         ms->msgout[3] = ms->msgin[3];
1194                                 if (ms->msgout[4] > ms->msgin[4])
1195                                         ms->msgout[4] = ms->msgin[4];
1196                                 set_sdtr(ms, ms->msgout[3], ms->msgout[4]);
1197                                 ms->msgphase = msg_out;
1198                         } else {
1199                                 set_sdtr(ms, ms->msgin[3], ms->msgin[4]);
1200                         }
1201                         break;
1202                 default:
1203                         goto reject;
1204                 }
1205                 break;
1206         case SAVE_POINTERS:
1207                 tp->saved_ptr = ms->data_ptr;
1208                 break;
1209         case RESTORE_POINTERS:
1210                 ms->data_ptr = tp->saved_ptr;
1211                 break;
1212         case DISCONNECT:
1213                 ms->phase = disconnecting;
1214                 break;
1215         case ABORT:
1216                 break;
1217         case MESSAGE_REJECT:
1218                 if (tp->sdtr_state == sdtr_sent)
1219                         set_sdtr(ms, 0, 0);
1220                 break;
1221         case NOP:
1222                 break;
1223         default:
1224                 if (IDENTIFY_BASE <= code && code <= IDENTIFY_BASE + 7) {
1225                         if (cmd == NULL) {
1226                                 do_abort(ms);
1227                                 ms->msgphase = msg_out;
1228                         } else if (code != cmd->device->lun + IDENTIFY_BASE) {
1229                                 printk(KERN_WARNING "mesh: lun mismatch "
1230                                        "(%d != %llu) on reselection from "
1231                                        "target %d\n", code - IDENTIFY_BASE,
1232                                        cmd->device->lun, ms->conn_tgt);
1233                         }
1234                         break;
1235                 }
1236                 goto reject;
1237         }
1238         return;
1239
1240  reject:
1241         printk(KERN_WARNING "mesh: rejecting message from target %d:",
1242                ms->conn_tgt);
1243         for (i = 0; i < ms->n_msgin; ++i)
1244                 printk(" %x", ms->msgin[i]);
1245         printk("\n");
1246         ms->msgout[0] = MESSAGE_REJECT;
1247         ms->n_msgout = 1;
1248         ms->msgphase = msg_out;
1249 }
1250
1251 /*
1252  * Set up DMA commands for transferring data.
1253  */
1254 static void set_dma_cmds(struct mesh_state *ms, struct scsi_cmnd *cmd)
1255 {
1256         int i, dma_cmd, total, off, dtot;
1257         struct scatterlist *scl;
1258         struct dbdma_cmd *dcmds;
1259
1260         dma_cmd = ms->tgts[ms->conn_tgt].data_goes_out?
1261                 OUTPUT_MORE: INPUT_MORE;
1262         dcmds = ms->dma_cmds;
1263         dtot = 0;
1264         if (cmd) {
1265                 int nseg;
1266
1267                 mesh_priv(cmd)->this_residual = scsi_bufflen(cmd);
1268
1269                 nseg = scsi_dma_map(cmd);
1270                 BUG_ON(nseg < 0);
1271
1272                 if (nseg) {
1273                         total = 0;
1274                         off = ms->data_ptr;
1275
1276                         scsi_for_each_sg(cmd, scl, nseg, i) {
1277                                 u32 dma_addr = sg_dma_address(scl);
1278                                 u32 dma_len = sg_dma_len(scl);
1279
1280                                 total += scl->length;
1281                                 if (off >= dma_len) {
1282                                         off -= dma_len;
1283                                         continue;
1284                                 }
1285                                 if (dma_len > 0xffff)
1286                                         panic("mesh: scatterlist element >= 64k");
1287                                 dcmds->req_count = cpu_to_le16(dma_len - off);
1288                                 dcmds->command = cpu_to_le16(dma_cmd);
1289                                 dcmds->phy_addr = cpu_to_le32(dma_addr + off);
1290                                 dcmds->xfer_status = 0;
1291                                 ++dcmds;
1292                                 dtot += dma_len - off;
1293                                 off = 0;
1294                         }
1295                 }
1296         }
1297         if (dtot == 0) {
1298                 /* Either the target has overrun our buffer,
1299                    or the caller didn't provide a buffer. */
1300                 static char mesh_extra_buf[64];
1301
1302                 dtot = sizeof(mesh_extra_buf);
1303                 dcmds->req_count = cpu_to_le16(dtot);
1304                 dcmds->phy_addr = cpu_to_le32(virt_to_phys(mesh_extra_buf));
1305                 dcmds->xfer_status = 0;
1306                 ++dcmds;
1307         }
1308         dma_cmd += OUTPUT_LAST - OUTPUT_MORE;
1309         dcmds[-1].command = cpu_to_le16(dma_cmd);
1310         memset(dcmds, 0, sizeof(*dcmds));
1311         dcmds->command = cpu_to_le16(DBDMA_STOP);
1312         ms->dma_count = dtot;
1313 }
1314
1315 static void halt_dma(struct mesh_state *ms)
1316 {
1317         volatile struct dbdma_regs __iomem *md = ms->dma;
1318         volatile struct mesh_regs __iomem *mr = ms->mesh;
1319         struct scsi_cmnd *cmd = ms->current_req;
1320         int t, nb;
1321
1322         if (!ms->tgts[ms->conn_tgt].data_goes_out) {
1323                 /* wait a little while until the fifo drains */
1324                 t = 50;
1325                 while (t > 0 && in_8(&mr->fifo_count) != 0
1326                        && (in_le32(&md->status) & ACTIVE) != 0) {
1327                         --t;
1328                         udelay(1);
1329                 }
1330         }
1331         out_le32(&md->control, RUN << 16);      /* turn off RUN bit */
1332         nb = (mr->count_hi << 8) + mr->count_lo;
1333         dlog(ms, "halt_dma fc/count=%.6x",
1334              MKWORD(0, mr->fifo_count, 0, nb));
1335         if (ms->tgts[ms->conn_tgt].data_goes_out)
1336                 nb += mr->fifo_count;
1337         /* nb is the number of bytes not yet transferred
1338            to/from the target. */
1339         ms->data_ptr -= nb;
1340         dlog(ms, "data_ptr %x", ms->data_ptr);
1341         if (ms->data_ptr < 0) {
1342                 printk(KERN_ERR "mesh: halt_dma: data_ptr=%d (nb=%d, ms=%p)\n",
1343                        ms->data_ptr, nb, ms);
1344                 ms->data_ptr = 0;
1345 #ifdef MESH_DBG
1346                 dumplog(ms, ms->conn_tgt);
1347                 dumpslog(ms);
1348 #endif /* MESH_DBG */
1349         } else if (cmd && scsi_bufflen(cmd) &&
1350                    ms->data_ptr > scsi_bufflen(cmd)) {
1351                 printk(KERN_DEBUG "mesh: target %d overrun, "
1352                        "data_ptr=%x total=%x goes_out=%d\n",
1353                        ms->conn_tgt, ms->data_ptr, scsi_bufflen(cmd),
1354                        ms->tgts[ms->conn_tgt].data_goes_out);
1355         }
1356         if (cmd)
1357                 scsi_dma_unmap(cmd);
1358         ms->dma_started = 0;
1359 }
1360
1361 static void phase_mismatch(struct mesh_state *ms)
1362 {
1363         volatile struct mesh_regs __iomem *mr = ms->mesh;
1364         int phase;
1365
1366         dlog(ms, "phasemm ch/cl/seq/fc=%.8x",
1367              MKWORD(mr->count_hi, mr->count_lo, mr->sequence, mr->fifo_count));
1368         phase = in_8(&mr->bus_status0) & BS0_PHASE;
1369         if (ms->msgphase == msg_out_xxx && phase == BP_MSGOUT) {
1370                 /* output the last byte of the message, without ATN */
1371                 out_8(&mr->count_lo, 1);
1372                 out_8(&mr->sequence, SEQ_MSGOUT + use_active_neg);
1373                 mesh_flush_io(mr);
1374                 udelay(1);
1375                 out_8(&mr->fifo, ms->msgout[ms->n_msgout-1]);
1376                 ms->msgphase = msg_out_last;
1377                 return;
1378         }
1379
1380         if (ms->msgphase == msg_in) {
1381                 get_msgin(ms);
1382                 if (ms->n_msgin)
1383                         handle_msgin(ms);
1384         }
1385
1386         if (ms->dma_started)
1387                 halt_dma(ms);
1388         if (mr->fifo_count) {
1389                 out_8(&mr->sequence, SEQ_FLUSHFIFO);
1390                 mesh_flush_io(mr);
1391                 udelay(1);
1392         }
1393
1394         ms->msgphase = msg_none;
1395         switch (phase) {
1396         case BP_DATAIN:
1397                 ms->tgts[ms->conn_tgt].data_goes_out = 0;
1398                 ms->phase = dataing;
1399                 break;
1400         case BP_DATAOUT:
1401                 ms->tgts[ms->conn_tgt].data_goes_out = 1;
1402                 ms->phase = dataing;
1403                 break;
1404         case BP_COMMAND:
1405                 ms->phase = commanding;
1406                 break;
1407         case BP_STATUS:
1408                 ms->phase = statusing;
1409                 break;
1410         case BP_MSGIN:
1411                 ms->msgphase = msg_in;
1412                 ms->n_msgin = 0;
1413                 break;
1414         case BP_MSGOUT:
1415                 ms->msgphase = msg_out;
1416                 if (ms->n_msgout == 0) {
1417                         if (ms->aborting) {
1418                                 do_abort(ms);
1419                         } else {
1420                                 if (ms->last_n_msgout == 0) {
1421                                         printk(KERN_DEBUG
1422                                                "mesh: no msg to repeat\n");
1423                                         ms->msgout[0] = NOP;
1424                                         ms->last_n_msgout = 1;
1425                                 }
1426                                 ms->n_msgout = ms->last_n_msgout;
1427                         }
1428                 }
1429                 break;
1430         default:
1431                 printk(KERN_DEBUG "mesh: unknown scsi phase %x\n", phase);
1432                 ms->stat = DID_ERROR;
1433                 mesh_done(ms, 1);
1434                 return;
1435         }
1436
1437         start_phase(ms);
1438 }
1439
1440 static void cmd_complete(struct mesh_state *ms)
1441 {
1442         volatile struct mesh_regs __iomem *mr = ms->mesh;
1443         struct scsi_cmnd *cmd = ms->current_req;
1444         struct mesh_target *tp = &ms->tgts[ms->conn_tgt];
1445         int seq, n, t;
1446
1447         dlog(ms, "cmd_complete fc=%x", mr->fifo_count);
1448         seq = use_active_neg + (ms->n_msgout? SEQ_ATN: 0);
1449         switch (ms->msgphase) {
1450         case msg_out_xxx:
1451                 /* huh?  we expected a phase mismatch */
1452                 ms->n_msgin = 0;
1453                 ms->msgphase = msg_in;
1454                 fallthrough;
1455
1456         case msg_in:
1457                 /* should have some message bytes in fifo */
1458                 get_msgin(ms);
1459                 n = msgin_length(ms);
1460                 if (ms->n_msgin < n) {
1461                         out_8(&mr->count_lo, n - ms->n_msgin);
1462                         out_8(&mr->sequence, SEQ_MSGIN + seq);
1463                 } else {
1464                         ms->msgphase = msg_none;
1465                         handle_msgin(ms);
1466                         start_phase(ms);
1467                 }
1468                 break;
1469
1470         case msg_in_bad:
1471                 out_8(&mr->sequence, SEQ_FLUSHFIFO);
1472                 mesh_flush_io(mr);
1473                 udelay(1);
1474                 out_8(&mr->count_lo, 1);
1475                 out_8(&mr->sequence, SEQ_MSGIN + SEQ_ATN + use_active_neg);
1476                 break;
1477
1478         case msg_out:
1479                 /*
1480                  * To get the right timing on ATN wrt ACK, we have
1481                  * to get the MESH to drop ACK, wait until REQ gets
1482                  * asserted, then drop ATN.  To do this we first
1483                  * issue a SEQ_MSGOUT with ATN and wait for REQ,
1484                  * then change the command to a SEQ_MSGOUT w/o ATN.
1485                  * If we don't see REQ in a reasonable time, we
1486                  * change the command to SEQ_MSGIN with ATN,
1487                  * wait for the phase mismatch interrupt, then
1488                  * issue the SEQ_MSGOUT without ATN.
1489                  */
1490                 out_8(&mr->count_lo, 1);
1491                 out_8(&mr->sequence, SEQ_MSGOUT + use_active_neg + SEQ_ATN);
1492                 t = 30;         /* wait up to 30us */
1493                 while ((in_8(&mr->bus_status0) & BS0_REQ) == 0 && --t >= 0)
1494                         udelay(1);
1495                 dlog(ms, "last_mbyte err/exc/fc/cl=%.8x",
1496                      MKWORD(mr->error, mr->exception,
1497                             mr->fifo_count, mr->count_lo));
1498                 if (in_8(&mr->interrupt) & (INT_ERROR | INT_EXCEPTION)) {
1499                         /* whoops, target didn't do what we expected */
1500                         ms->last_n_msgout = ms->n_msgout;
1501                         ms->n_msgout = 0;
1502                         if (in_8(&mr->interrupt) & INT_ERROR) {
1503                                 printk(KERN_ERR "mesh: error %x in msg_out\n",
1504                                        in_8(&mr->error));
1505                                 handle_error(ms);
1506                                 return;
1507                         }
1508                         if (in_8(&mr->exception) != EXC_PHASEMM)
1509                                 printk(KERN_ERR "mesh: exc %x in msg_out\n",
1510                                        in_8(&mr->exception));
1511                         else
1512                                 printk(KERN_DEBUG "mesh: bs0=%x in msg_out\n",
1513                                        in_8(&mr->bus_status0));
1514                         handle_exception(ms);
1515                         return;
1516                 }
1517                 if (in_8(&mr->bus_status0) & BS0_REQ) {
1518                         out_8(&mr->sequence, SEQ_MSGOUT + use_active_neg);
1519                         mesh_flush_io(mr);
1520                         udelay(1);
1521                         out_8(&mr->fifo, ms->msgout[ms->n_msgout-1]);
1522                         ms->msgphase = msg_out_last;
1523                 } else {
1524                         out_8(&mr->sequence, SEQ_MSGIN + use_active_neg + SEQ_ATN);
1525                         ms->msgphase = msg_out_xxx;
1526                 }
1527                 break;
1528
1529         case msg_out_last:
1530                 ms->last_n_msgout = ms->n_msgout;
1531                 ms->n_msgout = 0;
1532                 ms->msgphase = ms->expect_reply? msg_in: msg_none;
1533                 start_phase(ms);
1534                 break;
1535
1536         case msg_none:
1537                 switch (ms->phase) {
1538                 case idle:
1539                         printk(KERN_ERR "mesh: interrupt in idle phase?\n");
1540                         dumpslog(ms);
1541                         return;
1542                 case selecting:
1543                         dlog(ms, "Selecting phase at command completion",0);
1544                         ms->msgout[0] = IDENTIFY(ALLOW_RESEL(ms->conn_tgt),
1545                                                  (cmd? cmd->device->lun: 0));
1546                         ms->n_msgout = 1;
1547                         ms->expect_reply = 0;
1548                         if (ms->aborting) {
1549                                 ms->msgout[0] = ABORT;
1550                                 ms->n_msgout++;
1551                         } else if (tp->sdtr_state == do_sdtr) {
1552                                 /* add SDTR message */
1553                                 add_sdtr_msg(ms);
1554                                 ms->expect_reply = 1;
1555                                 tp->sdtr_state = sdtr_sent;
1556                         }
1557                         ms->msgphase = msg_out;
1558                         /*
1559                          * We need to wait for REQ before dropping ATN.
1560                          * We wait for at most 30us, then fall back to
1561                          * a scheme where we issue a SEQ_COMMAND with ATN,
1562                          * which will give us a phase mismatch interrupt
1563                          * when REQ does come, and then we send the message.
1564                          */
1565                         t = 230;                /* wait up to 230us */
1566                         while ((in_8(&mr->bus_status0) & BS0_REQ) == 0) {
1567                                 if (--t < 0) {
1568                                         dlog(ms, "impatient for req", ms->n_msgout);
1569                                         ms->msgphase = msg_none;
1570                                         break;
1571                                 }
1572                                 udelay(1);
1573                         }
1574                         break;
1575                 case dataing:
1576                         if (ms->dma_count != 0) {
1577                                 start_phase(ms);
1578                                 return;
1579                         }
1580                         /*
1581                          * We can get a phase mismatch here if the target
1582                          * changes to the status phase, even though we have
1583                          * had a command complete interrupt.  Then, if we
1584                          * issue the SEQ_STATUS command, we'll get a sequence
1585                          * error interrupt.  Which isn't so bad except that
1586                          * occasionally the mesh actually executes the
1587                          * SEQ_STATUS *as well as* giving us the sequence
1588                          * error and phase mismatch exception.
1589                          */
1590                         out_8(&mr->sequence, 0);
1591                         out_8(&mr->interrupt,
1592                               INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
1593                         halt_dma(ms);
1594                         break;
1595                 case statusing:
1596                         if (cmd) {
1597                                 struct mesh_cmd_priv *mcmd = mesh_priv(cmd);
1598
1599                                 mcmd->status = mr->fifo;
1600                                 if (DEBUG_TARGET(cmd))
1601                                         printk(KERN_DEBUG "mesh: status is %x\n",
1602                                                mcmd->status);
1603                         }
1604                         ms->msgphase = msg_in;
1605                         break;
1606                 case busfreeing:
1607                         mesh_done(ms, 1);
1608                         return;
1609                 case disconnecting:
1610                         ms->current_req = NULL;
1611                         ms->phase = idle;
1612                         mesh_start(ms);
1613                         return;
1614                 default:
1615                         break;
1616                 }
1617                 ++ms->phase;
1618                 start_phase(ms);
1619                 break;
1620         }
1621 }
1622
1623
1624 /*
1625  * Called by midlayer with host locked to queue a new
1626  * request
1627  */
1628 static int mesh_queue_lck(struct scsi_cmnd *cmd)
1629 {
1630         struct mesh_state *ms;
1631
1632         cmd->host_scribble = NULL;
1633
1634         ms = (struct mesh_state *) cmd->device->host->hostdata;
1635
1636         if (ms->request_q == NULL)
1637                 ms->request_q = cmd;
1638         else
1639                 ms->request_qtail->host_scribble = (void *) cmd;
1640         ms->request_qtail = cmd;
1641
1642         if (ms->phase == idle)
1643                 mesh_start(ms);
1644
1645         return 0;
1646 }
1647
1648 static DEF_SCSI_QCMD(mesh_queue)
1649
1650 /*
1651  * Called to handle interrupts, either call by the interrupt
1652  * handler (do_mesh_interrupt) or by other functions in
1653  * exceptional circumstances
1654  */
1655 static void mesh_interrupt(struct mesh_state *ms)
1656 {
1657         volatile struct mesh_regs __iomem *mr = ms->mesh;
1658         int intr;
1659
1660 #if 0
1661         if (ALLOW_DEBUG(ms->conn_tgt))
1662                 printk(KERN_DEBUG "mesh_intr, bs0=%x int=%x exc=%x err=%x "
1663                        "phase=%d msgphase=%d\n", mr->bus_status0,
1664                        mr->interrupt, mr->exception, mr->error,
1665                        ms->phase, ms->msgphase);
1666 #endif
1667         while ((intr = in_8(&mr->interrupt)) != 0) {
1668                 dlog(ms, "interrupt intr/err/exc/seq=%.8x",
1669                      MKWORD(intr, mr->error, mr->exception, mr->sequence));
1670                 if (intr & INT_ERROR) {
1671                         handle_error(ms);
1672                 } else if (intr & INT_EXCEPTION) {
1673                         handle_exception(ms);
1674                 } else if (intr & INT_CMDDONE) {
1675                         out_8(&mr->interrupt, INT_CMDDONE);
1676                         cmd_complete(ms);
1677                 }
1678         }
1679 }
1680
1681 /* Todo: here we can at least try to remove the command from the
1682  * queue if it isn't connected yet, and for pending command, assert
1683  * ATN until the bus gets freed.
1684  */
1685 static int mesh_abort(struct scsi_cmnd *cmd)
1686 {
1687         struct mesh_state *ms = (struct mesh_state *) cmd->device->host->hostdata;
1688
1689         printk(KERN_DEBUG "mesh_abort(%p)\n", cmd);
1690         mesh_dump_regs(ms);
1691         dumplog(ms, cmd->device->id);
1692         dumpslog(ms);
1693         return FAILED;
1694 }
1695
1696 /*
1697  * Called by the midlayer with the lock held to reset the
1698  * SCSI host and bus.
1699  * The midlayer will wait for devices to come back, we don't need
1700  * to do that ourselves
1701  */
1702 static int mesh_host_reset(struct scsi_cmnd *cmd)
1703 {
1704         struct mesh_state *ms = (struct mesh_state *) cmd->device->host->hostdata;
1705         volatile struct mesh_regs __iomem *mr = ms->mesh;
1706         volatile struct dbdma_regs __iomem *md = ms->dma;
1707         unsigned long flags;
1708
1709         printk(KERN_DEBUG "mesh_host_reset\n");
1710
1711         spin_lock_irqsave(ms->host->host_lock, flags);
1712
1713         if (ms->dma_started)
1714                 halt_dma(ms);
1715
1716         /* Reset the controller & dbdma channel */
1717         out_le32(&md->control, (RUN|PAUSE|FLUSH|WAKE) << 16);   /* stop dma */
1718         out_8(&mr->exception, 0xff);    /* clear all exception bits */
1719         out_8(&mr->error, 0xff);        /* clear all error bits */
1720         out_8(&mr->sequence, SEQ_RESETMESH);
1721         mesh_flush_io(mr);
1722         udelay(1);
1723         out_8(&mr->intr_mask, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
1724         out_8(&mr->source_id, ms->host->this_id);
1725         out_8(&mr->sel_timeout, 25);    /* 250ms */
1726         out_8(&mr->sync_params, ASYNC_PARAMS);
1727
1728         /* Reset the bus */
1729         out_8(&mr->bus_status1, BS1_RST);       /* assert RST */
1730         mesh_flush_io(mr);
1731         udelay(30);                     /* leave it on for >= 25us */
1732         out_8(&mr->bus_status1, 0);     /* negate RST */
1733
1734         /* Complete pending commands */
1735         handle_reset(ms);
1736
1737         spin_unlock_irqrestore(ms->host->host_lock, flags);
1738         return SUCCESS;
1739 }
1740
1741 static void set_mesh_power(struct mesh_state *ms, int state)
1742 {
1743         if (!machine_is(powermac))
1744                 return;
1745         if (state) {
1746                 pmac_call_feature(PMAC_FTR_MESH_ENABLE, macio_get_of_node(ms->mdev), 0, 1);
1747                 msleep(200);
1748         } else {
1749                 pmac_call_feature(PMAC_FTR_MESH_ENABLE, macio_get_of_node(ms->mdev), 0, 0);
1750                 msleep(10);
1751         }
1752 }
1753
1754
1755 #ifdef CONFIG_PM
1756 static int mesh_suspend(struct macio_dev *mdev, pm_message_t mesg)
1757 {
1758         struct mesh_state *ms = (struct mesh_state *)macio_get_drvdata(mdev);
1759         unsigned long flags;
1760
1761         switch (mesg.event) {
1762         case PM_EVENT_SUSPEND:
1763         case PM_EVENT_HIBERNATE:
1764         case PM_EVENT_FREEZE:
1765                 break;
1766         default:
1767                 return 0;
1768         }
1769         if (ms->phase == sleeping)
1770                 return 0;
1771
1772         scsi_block_requests(ms->host);
1773         spin_lock_irqsave(ms->host->host_lock, flags);
1774         while(ms->phase != idle) {
1775                 spin_unlock_irqrestore(ms->host->host_lock, flags);
1776                 msleep(10);
1777                 spin_lock_irqsave(ms->host->host_lock, flags);
1778         }
1779         ms->phase = sleeping;
1780         spin_unlock_irqrestore(ms->host->host_lock, flags);
1781         disable_irq(ms->meshintr);
1782         set_mesh_power(ms, 0);
1783
1784         return 0;
1785 }
1786
1787 static int mesh_resume(struct macio_dev *mdev)
1788 {
1789         struct mesh_state *ms = (struct mesh_state *)macio_get_drvdata(mdev);
1790         unsigned long flags;
1791
1792         if (ms->phase != sleeping)
1793                 return 0;
1794
1795         set_mesh_power(ms, 1);
1796         mesh_init(ms);
1797         spin_lock_irqsave(ms->host->host_lock, flags);
1798         mesh_start(ms);
1799         spin_unlock_irqrestore(ms->host->host_lock, flags);
1800         enable_irq(ms->meshintr);
1801         scsi_unblock_requests(ms->host);
1802
1803         return 0;
1804 }
1805
1806 #endif /* CONFIG_PM */
1807
1808 /*
1809  * If we leave drives set for synchronous transfers (especially
1810  * CDROMs), and reboot to MacOS, it gets confused, poor thing.
1811  * So, on reboot we reset the SCSI bus.
1812  */
1813 static int mesh_shutdown(struct macio_dev *mdev)
1814 {
1815         struct mesh_state *ms = (struct mesh_state *)macio_get_drvdata(mdev);
1816         volatile struct mesh_regs __iomem *mr;
1817         unsigned long flags;
1818
1819         printk(KERN_INFO "resetting MESH scsi bus(es)\n");
1820         spin_lock_irqsave(ms->host->host_lock, flags);
1821         mr = ms->mesh;
1822         out_8(&mr->intr_mask, 0);
1823         out_8(&mr->interrupt, INT_ERROR | INT_EXCEPTION | INT_CMDDONE);
1824         out_8(&mr->bus_status1, BS1_RST);
1825         mesh_flush_io(mr);
1826         udelay(30);
1827         out_8(&mr->bus_status1, 0);
1828         spin_unlock_irqrestore(ms->host->host_lock, flags);
1829
1830         return 0;
1831 }
1832
1833 static const struct scsi_host_template mesh_template = {
1834         .proc_name                      = "mesh",
1835         .name                           = "MESH",
1836         .queuecommand                   = mesh_queue,
1837         .eh_abort_handler               = mesh_abort,
1838         .eh_host_reset_handler          = mesh_host_reset,
1839         .can_queue                      = 20,
1840         .this_id                        = 7,
1841         .sg_tablesize                   = SG_ALL,
1842         .cmd_per_lun                    = 2,
1843         .max_segment_size               = 65535,
1844         .cmd_size                       = sizeof(struct mesh_cmd_priv),
1845 };
1846
1847 static int mesh_probe(struct macio_dev *mdev, const struct of_device_id *match)
1848 {
1849         struct device_node *mesh = macio_get_of_node(mdev);
1850         struct pci_dev* pdev = macio_get_pci_dev(mdev);
1851         int tgt, minper;
1852         const int *cfp;
1853         struct mesh_state *ms;
1854         struct Scsi_Host *mesh_host;
1855         void *dma_cmd_space;
1856         dma_addr_t dma_cmd_bus;
1857
1858         switch (mdev->bus->chip->type) {
1859         case macio_heathrow:
1860         case macio_gatwick:
1861         case macio_paddington:
1862                 use_active_neg = 0;
1863                 break;
1864         default:
1865                 use_active_neg = SEQ_ACTIVE_NEG;
1866         }
1867
1868         if (macio_resource_count(mdev) != 2 || macio_irq_count(mdev) != 2) {
1869                 printk(KERN_ERR "mesh: expected 2 addrs and 2 intrs"
1870                        " (got %d,%d)\n", macio_resource_count(mdev),
1871                        macio_irq_count(mdev));
1872                 return -ENODEV;
1873         }
1874
1875         if (macio_request_resources(mdev, "mesh") != 0) {
1876                 printk(KERN_ERR "mesh: unable to request memory resources");
1877                 return -EBUSY;
1878         }
1879         mesh_host = scsi_host_alloc(&mesh_template, sizeof(struct mesh_state));
1880         if (mesh_host == NULL) {
1881                 printk(KERN_ERR "mesh: couldn't register host");
1882                 goto out_release;
1883         }
1884
1885         mesh_host->base = macio_resource_start(mdev, 0);
1886         mesh_host->irq = macio_irq(mdev, 0);
1887         ms = (struct mesh_state *) mesh_host->hostdata;
1888         macio_set_drvdata(mdev, ms);
1889         ms->host = mesh_host;
1890         ms->mdev = mdev;
1891         ms->pdev = pdev;
1892
1893         ms->mesh = ioremap(macio_resource_start(mdev, 0), 0x1000);
1894         if (ms->mesh == NULL) {
1895                 printk(KERN_ERR "mesh: can't map registers\n");
1896                 goto out_free;
1897         }
1898         ms->dma = ioremap(macio_resource_start(mdev, 1), 0x1000);
1899         if (ms->dma == NULL) {
1900                 printk(KERN_ERR "mesh: can't map registers\n");
1901                 iounmap(ms->mesh);
1902                 goto out_free;
1903         }
1904
1905         ms->meshintr = macio_irq(mdev, 0);
1906         ms->dmaintr = macio_irq(mdev, 1);
1907
1908         /* Space for dma command list: +1 for stop command,
1909          * +1 to allow for aligning.
1910          */
1911         ms->dma_cmd_size = (mesh_host->sg_tablesize + 2) * sizeof(struct dbdma_cmd);
1912
1913         /* We use the PCI APIs for now until the generic one gets fixed
1914          * enough or until we get some macio-specific versions
1915          */
1916         dma_cmd_space = dma_alloc_coherent(&macio_get_pci_dev(mdev)->dev,
1917                                            ms->dma_cmd_size, &dma_cmd_bus,
1918                                            GFP_KERNEL);
1919         if (dma_cmd_space == NULL) {
1920                 printk(KERN_ERR "mesh: can't allocate DMA table\n");
1921                 goto out_unmap;
1922         }
1923
1924         ms->dma_cmds = (struct dbdma_cmd *) DBDMA_ALIGN(dma_cmd_space);
1925         ms->dma_cmd_space = dma_cmd_space;
1926         ms->dma_cmd_bus = dma_cmd_bus + ((unsigned long)ms->dma_cmds)
1927                 - (unsigned long)dma_cmd_space;
1928         ms->current_req = NULL;
1929         for (tgt = 0; tgt < 8; ++tgt) {
1930                 ms->tgts[tgt].sdtr_state = do_sdtr;
1931                 ms->tgts[tgt].sync_params = ASYNC_PARAMS;
1932                 ms->tgts[tgt].current_req = NULL;
1933         }
1934
1935         if ((cfp = of_get_property(mesh, "clock-frequency", NULL)))
1936                 ms->clk_freq = *cfp;
1937         else {
1938                 printk(KERN_INFO "mesh: assuming 50MHz clock frequency\n");
1939                 ms->clk_freq = 50000000;
1940         }
1941
1942         /* The maximum sync rate is clock / 5; increase
1943          * mesh_sync_period if necessary.
1944          */
1945         minper = 1000000000 / (ms->clk_freq / 5); /* ns */
1946         if (mesh_sync_period < minper)
1947                 mesh_sync_period = minper;
1948
1949         /* Power up the chip */
1950         set_mesh_power(ms, 1);
1951
1952         /* Set it up */
1953         mesh_init(ms);
1954
1955         /* Request interrupt */
1956         if (request_irq(ms->meshintr, do_mesh_interrupt, 0, "MESH", ms)) {
1957                 printk(KERN_ERR "MESH: can't get irq %d\n", ms->meshintr);
1958                 goto out_shutdown;
1959         }
1960
1961         /* Add scsi host & scan */
1962         if (scsi_add_host(mesh_host, &mdev->ofdev.dev))
1963                 goto out_release_irq;
1964         scsi_scan_host(mesh_host);
1965
1966         return 0;
1967
1968  out_release_irq:
1969         free_irq(ms->meshintr, ms);
1970  out_shutdown:
1971         /* shutdown & reset bus in case of error or macos can be confused
1972          * at reboot if the bus was set to synchronous mode already
1973          */
1974         mesh_shutdown(mdev);
1975         set_mesh_power(ms, 0);
1976         dma_free_coherent(&macio_get_pci_dev(mdev)->dev, ms->dma_cmd_size,
1977                             ms->dma_cmd_space, ms->dma_cmd_bus);
1978  out_unmap:
1979         iounmap(ms->dma);
1980         iounmap(ms->mesh);
1981  out_free:
1982         scsi_host_put(mesh_host);
1983  out_release:
1984         macio_release_resources(mdev);
1985
1986         return -ENODEV;
1987 }
1988
1989 static void mesh_remove(struct macio_dev *mdev)
1990 {
1991         struct mesh_state *ms = (struct mesh_state *)macio_get_drvdata(mdev);
1992         struct Scsi_Host *mesh_host = ms->host;
1993
1994         scsi_remove_host(mesh_host);
1995
1996         free_irq(ms->meshintr, ms);
1997
1998         /* Reset scsi bus */
1999         mesh_shutdown(mdev);
2000
2001         /* Shut down chip & termination */
2002         set_mesh_power(ms, 0);
2003
2004         /* Unmap registers & dma controller */
2005         iounmap(ms->mesh);
2006         iounmap(ms->dma);
2007
2008         /* Free DMA commands memory */
2009         dma_free_coherent(&macio_get_pci_dev(mdev)->dev, ms->dma_cmd_size,
2010                             ms->dma_cmd_space, ms->dma_cmd_bus);
2011
2012         /* Release memory resources */
2013         macio_release_resources(mdev);
2014
2015         scsi_host_put(mesh_host);
2016 }
2017
2018 static struct of_device_id mesh_match[] =
2019 {
2020         {
2021         .name           = "mesh",
2022         },
2023         {
2024         .type           = "scsi",
2025         .compatible     = "chrp,mesh0"
2026         },
2027         {},
2028 };
2029 MODULE_DEVICE_TABLE (of, mesh_match);
2030
2031 static struct macio_driver mesh_driver =
2032 {
2033         .driver = {
2034                 .name           = "mesh",
2035                 .owner          = THIS_MODULE,
2036                 .of_match_table = mesh_match,
2037         },
2038         .probe          = mesh_probe,
2039         .remove         = mesh_remove,
2040         .shutdown       = mesh_shutdown,
2041 #ifdef CONFIG_PM
2042         .suspend        = mesh_suspend,
2043         .resume         = mesh_resume,
2044 #endif
2045 };
2046
2047
2048 static int __init init_mesh(void)
2049 {
2050
2051         /* Calculate sync rate from module parameters */
2052         if (sync_rate > 10)
2053                 sync_rate = 10;
2054         if (sync_rate > 0) {
2055                 printk(KERN_INFO "mesh: configured for synchronous %d MB/s\n", sync_rate);
2056                 mesh_sync_period = 1000 / sync_rate;    /* ns */
2057                 mesh_sync_offset = 15;
2058         } else
2059                 printk(KERN_INFO "mesh: configured for asynchronous\n");
2060
2061         return macio_register_driver(&mesh_driver);
2062 }
2063
2064 static void __exit exit_mesh(void)
2065 {
2066         return macio_unregister_driver(&mesh_driver);
2067 }
2068
2069 module_init(init_mesh);
2070 module_exit(exit_mesh);