drivers/ata/libata-pmp.c

   1 /*
   2  * libata-pmp.c - libata port multiplier support
   3  *
   4  * Copyright (c) 2007  SUSE Linux Products GmbH
   5  * Copyright (c) 2007  Tejun Heo <teheo@suse.de>
   6  *
   7  * This file is released under the GPLv2.
   8  */
   9
  10 #include <linux/kernel.h>
  11 #include <linux/libata.h>
  12 #include "libata.h"
  13
  14 const struct ata_port_operations sata_pmp_port_ops = {
  15         .inherits               = &sata_port_ops,
  16         .pmp_prereset           = ata_std_prereset,
  17         .pmp_hardreset          = sata_std_hardreset,
  18         .pmp_postreset          = ata_std_postreset,
  19         .error_handler          = sata_pmp_error_handler,
  20 };
  21
  22 /**
  23  *      sata_pmp_read - read PMP register
  24  *      @link: link to read PMP register for
  25  *      @reg: register to read
  26  *      @r_val: resulting value
  27  *
  28  *      Read PMP register.
  29  *
  30  *      LOCKING:
  31  *      Kernel thread context (may sleep).
  32  *
  33  *      RETURNS:
  34  *      0 on success, AC_ERR_* mask on failure.
  35  */
  36 static unsigned int sata_pmp_read(struct ata_link *link, int reg, u32 *r_val)
  37 {
  38         struct ata_port *ap = link->ap;
  39         struct ata_device *pmp_dev = ap->link.device;
  40         struct ata_taskfile tf;
  41         unsigned int err_mask;
  42
  43         ata_tf_init(pmp_dev, &tf);
  44         tf.command = ATA_CMD_PMP_READ;
  45         tf.protocol = ATA_PROT_NODATA;
  46         tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_LBA48;
  47         tf.feature = reg;
  48         tf.device = link->pmp;
  49
  50         err_mask = ata_exec_internal(pmp_dev, &tf, NULL, DMA_NONE, NULL, 0,
  51                                      SATA_PMP_SCR_TIMEOUT);
  52         if (err_mask)
  53                 return err_mask;
  54
  55         *r_val = tf.nsect | tf.lbal << 8 | tf.lbam << 16 | tf.lbah << 24;
  56         return 0;
  57 }
  58
  59 /**
  60  *      sata_pmp_write - write PMP register
  61  *      @link: link to write PMP register for
  62  *      @reg: register to write
  63  *      @r_val: value to write
  64  *
  65  *      Write PMP register.
  66  *
  67  *      LOCKING:
  68  *      Kernel thread context (may sleep).
  69  *
  70  *      RETURNS:
  71  *      0 on success, AC_ERR_* mask on failure.
  72  */
  73 static unsigned int sata_pmp_write(struct ata_link *link, int reg, u32 val)
  74 {
  75         struct ata_port *ap = link->ap;
  76         struct ata_device *pmp_dev = ap->link.device;
  77         struct ata_taskfile tf;
  78
  79         ata_tf_init(pmp_dev, &tf);
  80         tf.command = ATA_CMD_PMP_WRITE;
  81         tf.protocol = ATA_PROT_NODATA;
  82         tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_LBA48;
  83         tf.feature = reg;
  84         tf.device = link->pmp;
  85         tf.nsect = val & 0xff;
  86         tf.lbal = (val >> 8) & 0xff;
  87         tf.lbam = (val >> 16) & 0xff;
  88         tf.lbah = (val >> 24) & 0xff;
  89
  90         return ata_exec_internal(pmp_dev, &tf, NULL, DMA_NONE, NULL, 0,
  91                                  SATA_PMP_SCR_TIMEOUT);
  92 }
  93
  94 /**
  95  *      sata_pmp_qc_defer_cmd_switch - qc_defer for command switching PMP
  96  *      @qc: ATA command in question
  97  *
  98  *      A host which has command switching PMP support cannot issue
  99  *      commands to multiple links simultaneously.
 100  *
 101  *      LOCKING:
 102  *      spin_lock_irqsave(host lock)
 103  *
 104  *      RETURNS:
 105  *      ATA_DEFER_* if deferring is needed, 0 otherwise.
 106  */
 107 int sata_pmp_qc_defer_cmd_switch(struct ata_queued_cmd *qc)
 108 {
 109         struct ata_link *link = qc->dev->link;
 110         struct ata_port *ap = link->ap;
 111
 112         if (ap->excl_link == NULL || ap->excl_link == link) {
 113                 if (ap->nr_active_links == 0 || ata_link_active(link)) {
 114                         qc->flags |= ATA_QCFLAG_CLEAR_EXCL;
 115                         return ata_std_qc_defer(qc);
 116                 }
 117
 118                 ap->excl_link = link;
 119         }
 120
 121         return ATA_DEFER_PORT;
 122 }
 123
 124 /**
 125  *      sata_pmp_scr_read - read PSCR
 126  *      @link: ATA link to read PSCR for
 127  *      @reg: PSCR to read
 128  *      @r_val: resulting value
 129  *
 130  *      Read PSCR @reg into @r_val for @link, to be called from
 131  *      ata_scr_read().
 132  *
 133  *      LOCKING:
 134  *      Kernel thread context (may sleep).
 135  *
 136  *      RETURNS:
 137  *      0 on success, -errno on failure.
 138  */
 139 int sata_pmp_scr_read(struct ata_link *link, int reg, u32 *r_val)
 140 {
 141         unsigned int err_mask;
 142
 143         if (reg > SATA_PMP_PSCR_CONTROL)
 144                 return -EINVAL;
 145
 146         err_mask = sata_pmp_read(link, reg, r_val);
 147         if (err_mask) {
 148                 ata_link_printk(link, KERN_WARNING, "failed to read SCR %d "
 149                                 "(Emask=0x%x)\n", reg, err_mask);
 150                 return -EIO;
 151         }
 152         return 0;
 153 }
 154
 155 /**
 156  *      sata_pmp_scr_write - write PSCR
 157  *      @link: ATA link to write PSCR for
 158  *      @reg: PSCR to write
 159  *      @val: value to be written
 160  *
 161  *      Write @val to PSCR @reg for @link, to be called from
 162  *      ata_scr_write() and ata_scr_write_flush().
 163  *
 164  *      LOCKING:
 165  *      Kernel thread context (may sleep).
 166  *
 167  *      RETURNS:
 168  *      0 on success, -errno on failure.
 169  */
 170 int sata_pmp_scr_write(struct ata_link *link, int reg, u32 val)
 171 {
 172         unsigned int err_mask;
 173
 174         if (reg > SATA_PMP_PSCR_CONTROL)
 175                 return -EINVAL;
 176
 177         err_mask = sata_pmp_write(link, reg, val);
 178         if (err_mask) {
 179                 ata_link_printk(link, KERN_WARNING, "failed to write SCR %d "
 180                                 "(Emask=0x%x)\n", reg, err_mask);
 181                 return -EIO;
 182         }
 183         return 0;
 184 }
 185
 186 /**
 187  *      sata_pmp_read_gscr - read GSCR block of SATA PMP
 188  *      @dev: PMP device
 189  *      @gscr: buffer to read GSCR block into
 190  *
 191  *      Read selected PMP GSCRs from the PMP at @dev.  This will serve
 192  *      as configuration and identification info for the PMP.
 193  *
 194  *      LOCKING:
 195  *      Kernel thread context (may sleep).
 196  *
 197  *      RETURNS:
 198  *      0 on success, -errno on failure.
 199  */
 200 static int sata_pmp_read_gscr(struct ata_device *dev, u32 *gscr)
 201 {
 202         static const int gscr_to_read[] = { 0, 1, 2, 32, 33, 64, 96 };
 203         int i;
 204
 205         for (i = 0; i < ARRAY_SIZE(gscr_to_read); i++) {
 206                 int reg = gscr_to_read[i];
 207                 unsigned int err_mask;
 208
 209                 err_mask = sata_pmp_read(dev->link, reg, &gscr[reg]);
 210                 if (err_mask) {
 211                         ata_dev_printk(dev, KERN_ERR, "failed to read PMP "
 212                                 "GSCR[%d] (Emask=0x%x)\n", reg, err_mask);
 213                         return -EIO;
 214                 }
 215         }
 216
 217         return 0;
 218 }
 219
 220 static const char *sata_pmp_spec_rev_str(const u32 *gscr)
 221 {
 222         u32 rev = gscr[SATA_PMP_GSCR_REV];
 223
 224         if (rev & (1 << 2))
 225                 return "1.1";
 226         if (rev & (1 << 1))
 227                 return "1.0";
 228         return "<unknown>";
 229 }
 230
 231 static int sata_pmp_configure(struct ata_device *dev, int print_info)
 232 {
 233         struct ata_port *ap = dev->link->ap;
 234         u32 *gscr = dev->gscr;
 235         unsigned int err_mask = 0;
 236         const char *reason;
 237         int nr_ports, rc;
 238
 239         nr_ports = sata_pmp_gscr_ports(gscr);
 240
 241         if (nr_ports <= 0 || nr_ports > SATA_PMP_MAX_PORTS) {
 242                 rc = -EINVAL;
 243                 reason = "invalid nr_ports";
 244                 goto fail;
 245         }
 246
 247         if ((ap->flags & ATA_FLAG_AN) &&
 248             (gscr[SATA_PMP_GSCR_FEAT] & SATA_PMP_FEAT_NOTIFY))
 249                 dev->flags |= ATA_DFLAG_AN;
 250
 251         /* monitor SERR_PHYRDY_CHG on fan-out ports */
 252         err_mask = sata_pmp_write(dev->link, SATA_PMP_GSCR_ERROR_EN,
 253                                   SERR_PHYRDY_CHG);
 254         if (err_mask) {
 255                 rc = -EIO;
 256                 reason = "failed to write GSCR_ERROR_EN";
 257                 goto fail;
 258         }
 259
 260         /* turn off notification till fan-out ports are reset and configured */
 261         if (gscr[SATA_PMP_GSCR_FEAT_EN] & SATA_PMP_FEAT_NOTIFY) {
 262                 gscr[SATA_PMP_GSCR_FEAT_EN] &= ~SATA_PMP_FEAT_NOTIFY;
 263
 264                 err_mask = sata_pmp_write(dev->link, SATA_PMP_GSCR_FEAT_EN,
 265                                           gscr[SATA_PMP_GSCR_FEAT_EN]);
 266                 if (err_mask) {
 267                         rc = -EIO;
 268                         reason = "failed to write GSCR_FEAT_EN";
 269                         goto fail;
 270                 }
 271         }
 272
 273         if (print_info) {
 274                 ata_dev_printk(dev, KERN_INFO, "Port Multiplier %s, "
 275                                "0x%04x:0x%04x r%d, %d ports, feat 0x%x/0x%x\n",
 276                                sata_pmp_spec_rev_str(gscr),
 277                                sata_pmp_gscr_vendor(gscr),
 278                                sata_pmp_gscr_devid(gscr),
 279                                sata_pmp_gscr_rev(gscr),
 280                                nr_ports, gscr[SATA_PMP_GSCR_FEAT_EN],
 281                                gscr[SATA_PMP_GSCR_FEAT]);
 282
 283                 if (!(dev->flags & ATA_DFLAG_AN))
 284                         ata_dev_printk(dev, KERN_INFO,
 285                                 "Asynchronous notification not supported, "
 286                                 "hotplug won't\n         work on fan-out "
 287                                 "ports. Use warm-plug instead.\n");
 288         }
 289
 290         return 0;
 291
 292  fail:
 293         ata_dev_printk(dev, KERN_ERR,
 294                        "failed to configure Port Multiplier (%s, Emask=0x%x)\n",
 295                        reason, err_mask);
 296         return rc;
 297 }
 298
 299 static int sata_pmp_init_links(struct ata_port *ap, int nr_ports)
 300 {
 301         struct ata_link *pmp_link = ap->pmp_link;
 302         int i;
 303
 304         if (!pmp_link) {
 305                 pmp_link = kzalloc(sizeof(pmp_link[0]) * SATA_PMP_MAX_PORTS,
 306                                    GFP_NOIO);
 307                 if (!pmp_link)
 308                         return -ENOMEM;
 309
 310                 for (i = 0; i < SATA_PMP_MAX_PORTS; i++)
 311                         ata_link_init(ap, &pmp_link[i], i);
 312
 313                 ap->pmp_link = pmp_link;
 314         }
 315
 316         for (i = 0; i < nr_ports; i++) {
 317                 struct ata_link *link = &pmp_link[i];
 318                 struct ata_eh_context *ehc = &link->eh_context;
 319
 320                 link->flags = 0;
 321                 ehc->i.probe_mask |= ATA_ALL_DEVICES;
 322                 ehc->i.action |= ATA_EH_RESET;
 323         }
 324
 325         return 0;
 326 }
 327
 328 static void sata_pmp_quirks(struct ata_port *ap)
 329 {
 330         u32 *gscr = ap->link.device->gscr;
 331         u16 vendor = sata_pmp_gscr_vendor(gscr);
 332         u16 devid = sata_pmp_gscr_devid(gscr);
 333         struct ata_link *link;
 334
 335         if (vendor == 0x1095 && devid == 0x3726) {
 336                 /* sil3726 quirks */
 337                 ata_port_for_each_link(link, ap) {
 338                         /* class code report is unreliable */
 339                         if (link->pmp < 5)
 340                                 link->flags |= ATA_LFLAG_ASSUME_ATA;
 341
 342                         /* port 5 is for SEMB device and it doesn't like SRST */
 343                         if (link->pmp == 5)
 344                                 link->flags |= ATA_LFLAG_NO_SRST |
 345                                                ATA_LFLAG_ASSUME_SEMB;
 346                 }
 347         } else if (vendor == 0x1095 && devid == 0x4723) {
 348                 /* sil4723 quirks */
 349                 ata_port_for_each_link(link, ap) {
 350                         /* class code report is unreliable */
 351                         if (link->pmp < 2)
 352                                 link->flags |= ATA_LFLAG_ASSUME_ATA;
 353
 354                         /* the config device at port 2 locks up on SRST */
 355                         if (link->pmp == 2)
 356                                 link->flags |= ATA_LFLAG_NO_SRST |
 357                                                ATA_LFLAG_ASSUME_ATA;
 358                 }
 359         } else if (vendor == 0x1095 && devid == 0x4726) {
 360                 /* sil4726 quirks */
 361                 ata_port_for_each_link(link, ap) {
 362                         /* Class code report is unreliable and SRST
 363                          * times out under certain configurations.
 364                          * Config device can be at port 0 or 5 and
 365                          * locks up on SRST.
 366                          */
 367                         if (link->pmp <= 5)
 368                                 link->flags |= ATA_LFLAG_NO_SRST |
 369                                                ATA_LFLAG_ASSUME_ATA;
 370
 371                         /* Port 6 is for SEMB device which doesn't
 372                          * like SRST either.
 373                          */
 374                         if (link->pmp == 6)
 375                                 link->flags |= ATA_LFLAG_NO_SRST |
 376                                                ATA_LFLAG_ASSUME_SEMB;
 377                 }
 378         } else if (vendor == 0x1095 && (devid == 0x5723 || devid == 0x5733 ||
 379                                         devid == 0x5734 || devid == 0x5744)) {
 380                 /* sil5723/5744 quirks */
 381
 382                 /* sil5723/5744 has either two or three downstream
 383                  * ports depending on operation mode.  The last port
 384                  * is empty if any actual IO device is available or
 385                  * occupied by a pseudo configuration device
 386                  * otherwise.  Don't try hard to recover it.
 387                  */
 388                 ap->pmp_link[ap->nr_pmp_links - 1].flags |= ATA_LFLAG_NO_RETRY;
 389         }
 390 }
 391
 392 /**
 393  *      sata_pmp_attach - attach a SATA PMP device
 394  *      @dev: SATA PMP device to attach
 395  *
 396  *      Configure and attach SATA PMP device @dev.  This function is
 397  *      also responsible for allocating and initializing PMP links.
 398  *
 399  *      LOCKING:
 400  *      Kernel thread context (may sleep).
 401  *
 402  *      RETURNS:
 403  *      0 on success, -errno on failure.
 404  */
 405 int sata_pmp_attach(struct ata_device *dev)
 406 {
 407         struct ata_link *link = dev->link;
 408         struct ata_port *ap = link->ap;
 409         unsigned long flags;
 410         struct ata_link *tlink;
 411         int rc;
 412
 413         /* is it hanging off the right place? */
 414         if (!sata_pmp_supported(ap)) {
 415                 ata_dev_printk(dev, KERN_ERR,
 416                                "host does not support Port Multiplier\n");
 417                 return -EINVAL;
 418         }
 419
 420         if (!ata_is_host_link(link)) {
 421                 ata_dev_printk(dev, KERN_ERR,
 422                                "Port Multipliers cannot be nested\n");
 423                 return -EINVAL;
 424         }
 425
 426         if (dev->devno) {
 427                 ata_dev_printk(dev, KERN_ERR,
 428                                "Port Multiplier must be the first device\n");
 429                 return -EINVAL;
 430         }
 431
 432         WARN_ON(link->pmp != 0);
 433         link->pmp = SATA_PMP_CTRL_PORT;
 434
 435         /* read GSCR block */
 436         rc = sata_pmp_read_gscr(dev, dev->gscr);
 437         if (rc)
 438                 goto fail;
 439
 440         /* config PMP */
 441         rc = sata_pmp_configure(dev, 1);
 442         if (rc)
 443                 goto fail;
 444
 445         rc = sata_pmp_init_links(ap, sata_pmp_gscr_ports(dev->gscr));
 446         if (rc) {
 447                 ata_dev_printk(dev, KERN_INFO,
 448                                "failed to initialize PMP links\n");
 449                 goto fail;
 450         }
 451
 452         /* attach it */
 453         spin_lock_irqsave(ap->lock, flags);
 454         WARN_ON(ap->nr_pmp_links);
 455         ap->nr_pmp_links = sata_pmp_gscr_ports(dev->gscr);
 456         spin_unlock_irqrestore(ap->lock, flags);
 457
 458         sata_pmp_quirks(ap);
 459
 460         if (ap->ops->pmp_attach)
 461                 ap->ops->pmp_attach(ap);
 462
 463         ata_port_for_each_link(tlink, ap)
 464                 sata_link_init_spd(tlink);
 465
 466         ata_acpi_associate_sata_port(ap);
 467
 468         return 0;
 469
 470  fail:
 471         link->pmp = 0;
 472         return rc;
 473 }
 474
 475 /**
 476  *      sata_pmp_detach - detach a SATA PMP device
 477  *      @dev: SATA PMP device to detach
 478  *
 479  *      Detach SATA PMP device @dev.  This function is also
 480  *      responsible for deconfiguring PMP links.
 481  *
 482  *      LOCKING:
 483  *      Kernel thread context (may sleep).
 484  */
 485 static void sata_pmp_detach(struct ata_device *dev)
 486 {
 487         struct ata_link *link = dev->link;
 488         struct ata_port *ap = link->ap;
 489         struct ata_link *tlink;
 490         unsigned long flags;
 491
 492         ata_dev_printk(dev, KERN_INFO, "Port Multiplier detaching\n");
 493
 494         WARN_ON(!ata_is_host_link(link) || dev->devno ||
 495                 link->pmp != SATA_PMP_CTRL_PORT);
 496
 497         if (ap->ops->pmp_detach)
 498                 ap->ops->pmp_detach(ap);
 499
 500         ata_port_for_each_link(tlink, ap)
 501                 ata_eh_detach_dev(tlink->device);
 502
 503         spin_lock_irqsave(ap->lock, flags);
 504         ap->nr_pmp_links = 0;
 505         link->pmp = 0;
 506         spin_unlock_irqrestore(ap->lock, flags);
 507
 508         ata_acpi_associate_sata_port(ap);
 509 }
 510
 511 /**
 512  *      sata_pmp_same_pmp - does new GSCR matches the configured PMP?
 513  *      @dev: PMP device to compare against
 514  *      @new_gscr: GSCR block of the new device
 515  *
 516  *      Compare @new_gscr against @dev and determine whether @dev is
 517  *      the PMP described by @new_gscr.
 518  *
 519  *      LOCKING:
 520  *      None.
 521  *
 522  *      RETURNS:
 523  *      1 if @dev matches @new_gscr, 0 otherwise.
 524  */
 525 static int sata_pmp_same_pmp(struct ata_device *dev, const u32 *new_gscr)
 526 {
 527         const u32 *old_gscr = dev->gscr;
 528         u16 old_vendor, new_vendor, old_devid, new_devid;
 529         int old_nr_ports, new_nr_ports;
 530
 531         old_vendor = sata_pmp_gscr_vendor(old_gscr);
 532         new_vendor = sata_pmp_gscr_vendor(new_gscr);
 533         old_devid = sata_pmp_gscr_devid(old_gscr);
 534         new_devid = sata_pmp_gscr_devid(new_gscr);
 535         old_nr_ports = sata_pmp_gscr_ports(old_gscr);
 536         new_nr_ports = sata_pmp_gscr_ports(new_gscr);
 537
 538         if (old_vendor != new_vendor) {
 539                 ata_dev_printk(dev, KERN_INFO, "Port Multiplier "
 540                                "vendor mismatch '0x%x' != '0x%x'\n",
 541                                old_vendor, new_vendor);
 542                 return 0;
 543         }
 544
 545         if (old_devid != new_devid) {
 546                 ata_dev_printk(dev, KERN_INFO, "Port Multiplier "
 547                                "device ID mismatch '0x%x' != '0x%x'\n",
 548                                old_devid, new_devid);
 549                 return 0;
 550         }
 551
 552         if (old_nr_ports != new_nr_ports) {
 553                 ata_dev_printk(dev, KERN_INFO, "Port Multiplier "
 554                                "nr_ports mismatch '0x%x' != '0x%x'\n",
 555                                old_nr_ports, new_nr_ports);
 556                 return 0;
 557         }
 558
 559         return 1;
 560 }
 561
 562 /**
 563  *      sata_pmp_revalidate - revalidate SATA PMP
 564  *      @dev: PMP device to revalidate
 565  *      @new_class: new class code
 566  *
 567  *      Re-read GSCR block and make sure @dev is still attached to the
 568  *      port and properly configured.
 569  *
 570  *      LOCKING:
 571  *      Kernel thread context (may sleep).
 572  *
 573  *      RETURNS:
 574  *      0 on success, -errno otherwise.
 575  */
 576 static int sata_pmp_revalidate(struct ata_device *dev, unsigned int new_class)
 577 {
 578         struct ata_link *link = dev->link;
 579         struct ata_port *ap = link->ap;
 580         u32 *gscr = (void *)ap->sector_buf;
 581         int rc;
 582
 583         DPRINTK("ENTER\n");
 584
 585         ata_eh_about_to_do(link, NULL, ATA_EH_REVALIDATE);
 586
 587         if (!ata_dev_enabled(dev)) {
 588                 rc = -ENODEV;
 589                 goto fail;
 590         }
 591
 592         /* wrong class? */
 593         if (ata_class_enabled(new_class) && new_class != ATA_DEV_PMP) {
 594                 rc = -ENODEV;
 595                 goto fail;
 596         }
 597
 598         /* read GSCR */
 599         rc = sata_pmp_read_gscr(dev, gscr);
 600         if (rc)
 601                 goto fail;
 602
 603         /* is the pmp still there? */
 604         if (!sata_pmp_same_pmp(dev, gscr)) {
 605                 rc = -ENODEV;
 606                 goto fail;
 607         }
 608
 609         memcpy(dev->gscr, gscr, sizeof(gscr[0]) * SATA_PMP_GSCR_DWORDS);
 610
 611         rc = sata_pmp_configure(dev, 0);
 612         if (rc)
 613                 goto fail;
 614
 615         ata_eh_done(link, NULL, ATA_EH_REVALIDATE);
 616
 617         DPRINTK("EXIT, rc=0\n");
 618         return 0;
 619
 620  fail:
 621         ata_dev_printk(dev, KERN_ERR,
 622                        "PMP revalidation failed (errno=%d)\n", rc);
 623         DPRINTK("EXIT, rc=%d\n", rc);
 624         return rc;
 625 }
 626
 627 /**
 628  *      sata_pmp_revalidate_quick - revalidate SATA PMP quickly
 629  *      @dev: PMP device to revalidate
 630  *
 631  *      Make sure the attached PMP is accessible.
 632  *
 633  *      LOCKING:
 634  *      Kernel thread context (may sleep).
 635  *
 636  *      RETURNS:
 637  *      0 on success, -errno otherwise.
 638  */
 639 static int sata_pmp_revalidate_quick(struct ata_device *dev)
 640 {
 641         unsigned int err_mask;
 642         u32 prod_id;
 643
 644         err_mask = sata_pmp_read(dev->link, SATA_PMP_GSCR_PROD_ID, &prod_id);
 645         if (err_mask) {
 646                 ata_dev_printk(dev, KERN_ERR, "failed to read PMP product ID "
 647                                "(Emask=0x%x)\n", err_mask);
 648                 return -EIO;
 649         }
 650
 651         if (prod_id != dev->gscr[SATA_PMP_GSCR_PROD_ID]) {
 652                 ata_dev_printk(dev, KERN_ERR, "PMP product ID mismatch\n");
 653                 /* something weird is going on, request full PMP recovery */
 654                 return -EIO;
 655         }
 656
 657         return 0;
 658 }
 659
 660 /**
 661  *      sata_pmp_eh_recover_pmp - recover PMP
 662  *      @ap: ATA port PMP is attached to
 663  *      @prereset: prereset method (can be NULL)
 664  *      @softreset: softreset method
 665  *      @hardreset: hardreset method
 666  *      @postreset: postreset method (can be NULL)
 667  *
 668  *      Recover PMP attached to @ap.  Recovery procedure is somewhat
 669  *      similar to that of ata_eh_recover() except that reset should
 670  *      always be performed in hard->soft sequence and recovery
 671  *      failure results in PMP detachment.
 672  *
 673  *      LOCKING:
 674  *      Kernel thread context (may sleep).
 675  *
 676  *      RETURNS:
 677  *      0 on success, -errno on failure.
 678  */
 679 static int sata_pmp_eh_recover_pmp(struct ata_port *ap,
 680                 ata_prereset_fn_t prereset, ata_reset_fn_t softreset,
 681                 ata_reset_fn_t hardreset, ata_postreset_fn_t postreset)
 682 {
 683         struct ata_link *link = &ap->link;
 684         struct ata_eh_context *ehc = &link->eh_context;
 685         struct ata_device *dev = link->device;
 686         int tries = ATA_EH_PMP_TRIES;
 687         int detach = 0, rc = 0;
 688         int reval_failed = 0;
 689
 690         DPRINTK("ENTER\n");
 691
 692         if (dev->flags & ATA_DFLAG_DETACH) {
 693                 detach = 1;
 694                 goto fail;
 695         }
 696
 697  retry:
 698         ehc->classes[0] = ATA_DEV_UNKNOWN;
 699
 700         if (ehc->i.action & ATA_EH_RESET) {
 701                 struct ata_link *tlink;
 702
 703                 ata_eh_freeze_port(ap);
 704
 705                 /* reset */
 706                 rc = ata_eh_reset(link, 0, prereset, softreset, hardreset,
 707                                   postreset);
 708                 if (rc) {
 709                         ata_link_printk(link, KERN_ERR,
 710                                         "failed to reset PMP, giving up\n");
 711                         goto fail;
 712                 }
 713
 714                 ata_eh_thaw_port(ap);
 715
 716                 /* PMP is reset, SErrors cannot be trusted, scan all */
 717                 ata_port_for_each_link(tlink, ap) {
 718                         struct ata_eh_context *ehc = &tlink->eh_context;
 719
 720                         ehc->i.probe_mask |= ATA_ALL_DEVICES;
 721                         ehc->i.action |= ATA_EH_RESET;
 722                 }
 723         }
 724
 725         /* If revalidation is requested, revalidate and reconfigure;
 726          * otherwise, do quick revalidation.
 727          */
 728         if (ehc->i.action & ATA_EH_REVALIDATE)
 729                 rc = sata_pmp_revalidate(dev, ehc->classes[0]);
 730         else
 731                 rc = sata_pmp_revalidate_quick(dev);
 732
 733         if (rc) {
 734                 tries--;
 735
 736                 if (rc == -ENODEV) {
 737                         ehc->i.probe_mask |= ATA_ALL_DEVICES;
 738                         detach = 1;
 739                         /* give it just two more chances */
 740                         tries = min(tries, 2);
 741                 }
 742
 743                 if (tries) {
 744                         int sleep = ehc->i.flags & ATA_EHI_DID_RESET;
 745
 746                         /* consecutive revalidation failures? speed down */
 747                         if (reval_failed)
 748                                 sata_down_spd_limit(link);
 749                         else
 750                                 reval_failed = 1;
 751
 752                         ata_dev_printk(dev, KERN_WARNING,
 753                                        "retrying reset%s\n",
 754                                        sleep ? " in 5 secs" : "");
 755                         if (sleep)
 756                                 ssleep(5);
 757                         ehc->i.action |= ATA_EH_RESET;
 758                         goto retry;
 759                 } else {
 760                         ata_dev_printk(dev, KERN_ERR, "failed to recover PMP "
 761                                        "after %d tries, giving up\n",
 762                                        ATA_EH_PMP_TRIES);
 763                         goto fail;
 764                 }
 765         }
 766
 767         /* okay, PMP resurrected */
 768         ehc->i.flags = 0;
 769
 770         DPRINTK("EXIT, rc=0\n");
 771         return 0;
 772
 773  fail:
 774         sata_pmp_detach(dev);
 775         if (detach)
 776                 ata_eh_detach_dev(dev);
 777         else
 778                 ata_dev_disable(dev);
 779
 780         DPRINTK("EXIT, rc=%d\n", rc);
 781         return rc;
 782 }
 783
 784 static int sata_pmp_eh_handle_disabled_links(struct ata_port *ap)
 785 {
 786         struct ata_link *link;
 787         unsigned long flags;
 788         int rc;
 789
 790         spin_lock_irqsave(ap->lock, flags);
 791
 792         ata_port_for_each_link(link, ap) {
 793                 if (!(link->flags & ATA_LFLAG_DISABLED))
 794                         continue;
 795
 796                 spin_unlock_irqrestore(ap->lock, flags);
 797
 798                 /* Some PMPs require hardreset sequence to get
 799                  * SError.N working.
 800                  */
 801                 sata_link_hardreset(link, sata_deb_timing_normal,
 802                                 jiffies + ATA_TMOUT_INTERNAL_QUICK, NULL, NULL);
 803
 804                 /* unconditionally clear SError.N */
 805                 rc = sata_scr_write(link, SCR_ERROR, SERR_PHYRDY_CHG);
 806                 if (rc) {
 807                         ata_link_printk(link, KERN_ERR, "failed to clear "
 808                                         "SError.N (errno=%d)\n", rc);
 809                         return rc;
 810                 }
 811
 812                 spin_lock_irqsave(ap->lock, flags);
 813         }
 814
 815         spin_unlock_irqrestore(ap->lock, flags);
 816
 817         return 0;
 818 }
 819
 820 static int sata_pmp_handle_link_fail(struct ata_link *link, int *link_tries)
 821 {
 822         struct ata_port *ap = link->ap;
 823         unsigned long flags;
 824
 825         if (link_tries[link->pmp] && --link_tries[link->pmp])
 826                 return 1;
 827
 828         /* disable this link */
 829         if (!(link->flags & ATA_LFLAG_DISABLED)) {
 830                 ata_link_printk(link, KERN_WARNING,
 831                         "failed to recover link after %d tries, disabling\n",
 832                         ATA_EH_PMP_LINK_TRIES);
 833
 834                 spin_lock_irqsave(ap->lock, flags);
 835                 link->flags |= ATA_LFLAG_DISABLED;
 836                 spin_unlock_irqrestore(ap->lock, flags);
 837         }
 838
 839         ata_dev_disable(link->device);
 840         link->eh_context.i.action = 0;
 841
 842         return 0;
 843 }
 844
 845 /**
 846  *      sata_pmp_eh_recover - recover PMP-enabled port
 847  *      @ap: ATA port to recover
 848  *
 849  *      Drive EH recovery operation for PMP enabled port @ap.  This
 850  *      function recovers host and PMP ports with proper retrials and
 851  *      fallbacks.  Actual recovery operations are performed using
 852  *      ata_eh_recover() and sata_pmp_eh_recover_pmp().
 853  *
 854  *      LOCKING:
 855  *      Kernel thread context (may sleep).
 856  *
 857  *      RETURNS:
 858  *      0 on success, -errno on failure.
 859  */
 860 static int sata_pmp_eh_recover(struct ata_port *ap)
 861 {
 862         struct ata_port_operations *ops = ap->ops;
 863         int pmp_tries, link_tries[SATA_PMP_MAX_PORTS];
 864         struct ata_link *pmp_link = &ap->link;
 865         struct ata_device *pmp_dev = pmp_link->device;
 866         struct ata_eh_context *pmp_ehc = &pmp_link->eh_context;
 867         struct ata_link *link;
 868         struct ata_device *dev;
 869         unsigned int err_mask;
 870         u32 gscr_error, sntf;
 871         int cnt, rc;
 872
 873         pmp_tries = ATA_EH_PMP_TRIES;
 874         ata_port_for_each_link(link, ap)
 875                 link_tries[link->pmp] = ATA_EH_PMP_LINK_TRIES;
 876
 877  retry:
 878         /* PMP attached? */
 879         if (!sata_pmp_attached(ap)) {
 880                 rc = ata_eh_recover(ap, ops->prereset, ops->softreset,
 881                                     ops->hardreset, ops->postreset, NULL);
 882                 if (rc) {
 883                         ata_link_for_each_dev(dev, &ap->link)
 884                                 ata_dev_disable(dev);
 885                         return rc;
 886                 }
 887
 888                 if (pmp_dev->class != ATA_DEV_PMP)
 889                         return 0;
 890
 891                 /* new PMP online */
 892                 ata_port_for_each_link(link, ap)
 893                         link_tries[link->pmp] = ATA_EH_PMP_LINK_TRIES;
 894
 895                 /* fall through */
 896         }
 897
 898         /* recover pmp */
 899         rc = sata_pmp_eh_recover_pmp(ap, ops->prereset, ops->softreset,
 900                                      ops->hardreset, ops->postreset);
 901         if (rc)
 902                 goto pmp_fail;
 903
 904         /* handle disabled links */
 905         rc = sata_pmp_eh_handle_disabled_links(ap);
 906         if (rc)
 907                 goto pmp_fail;
 908
 909         /* recover links */
 910         rc = ata_eh_recover(ap, ops->pmp_prereset, ops->pmp_softreset,
 911                             ops->pmp_hardreset, ops->pmp_postreset, &link);
 912         if (rc)
 913                 goto link_fail;
 914
 915         /* Connection status might have changed while resetting other
 916          * links, check SATA_PMP_GSCR_ERROR before returning.
 917          */
 918
 919         /* clear SNotification */
 920         rc = sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf);
 921         if (rc == 0)
 922                 sata_scr_write(&ap->link, SCR_NOTIFICATION, sntf);
 923
 924         /* enable notification */
 925         if (pmp_dev->flags & ATA_DFLAG_AN) {
 926                 pmp_dev->gscr[SATA_PMP_GSCR_FEAT_EN] |= SATA_PMP_FEAT_NOTIFY;
 927
 928                 err_mask = sata_pmp_write(pmp_dev->link, SATA_PMP_GSCR_FEAT_EN,
 929                                           pmp_dev->gscr[SATA_PMP_GSCR_FEAT_EN]);
 930                 if (err_mask) {
 931                         ata_dev_printk(pmp_dev, KERN_ERR, "failed to write "
 932                                        "PMP_FEAT_EN (Emask=0x%x)\n", err_mask);
 933                         rc = -EIO;
 934                         goto pmp_fail;
 935                 }
 936         }
 937
 938         /* check GSCR_ERROR */
 939         err_mask = sata_pmp_read(pmp_link, SATA_PMP_GSCR_ERROR, &gscr_error);
 940         if (err_mask) {
 941                 ata_dev_printk(pmp_dev, KERN_ERR, "failed to read "
 942                                "PMP_GSCR_ERROR (Emask=0x%x)\n", err_mask);
 943                 rc = -EIO;
 944                 goto pmp_fail;
 945         }
 946
 947         cnt = 0;
 948         ata_port_for_each_link(link, ap) {
 949                 if (!(gscr_error & (1 << link->pmp)))
 950                         continue;
 951
 952                 if (sata_pmp_handle_link_fail(link, link_tries)) {
 953                         ata_ehi_hotplugged(&link->eh_context.i);
 954                         cnt++;
 955                 } else {
 956                         ata_link_printk(link, KERN_WARNING,
 957                                 "PHY status changed but maxed out on retries, "
 958                                 "giving up\n");
 959                         ata_link_printk(link, KERN_WARNING,
 960                                 "Manully issue scan to resume this link\n");
 961                 }
 962         }
 963
 964         if (cnt) {
 965                 ata_port_printk(ap, KERN_INFO, "PMP SError.N set for some "
 966                                 "ports, repeating recovery\n");
 967                 goto retry;
 968         }
 969
 970         return 0;
 971
 972  link_fail:
 973         if (sata_pmp_handle_link_fail(link, link_tries)) {
 974                 pmp_ehc->i.action |= ATA_EH_RESET;
 975                 goto retry;
 976         }
 977
 978         /* fall through */
 979  pmp_fail:
 980         /* Control always ends up here after detaching PMP.  Shut up
 981          * and return if we're unloading.
 982          */
 983         if (ap->pflags & ATA_PFLAG_UNLOADING)
 984                 return rc;
 985
 986         if (!sata_pmp_attached(ap))
 987                 goto retry;
 988
 989         if (--pmp_tries) {
 990                 ata_port_printk(ap, KERN_WARNING,
 991                                 "failed to recover PMP, retrying in 5 secs\n");
 992                 pmp_ehc->i.action |= ATA_EH_RESET;
 993                 ssleep(5);
 994                 goto retry;
 995         }
 996
 997         ata_port_printk(ap, KERN_ERR,
 998                         "failed to recover PMP after %d tries, giving up\n",
 999                         ATA_EH_PMP_TRIES);
1000         sata_pmp_detach(pmp_dev);
1001         ata_dev_disable(pmp_dev);
1002
1003         return rc;
1004 }
1005
1006 /**
1007  *      sata_pmp_error_handler - do standard error handling for PMP-enabled host
1008  *      @ap: host port to handle error for
1009  *
1010  *      Perform standard error handling sequence for PMP-enabled host
1011  *      @ap.
1012  *
1013  *      LOCKING:
1014  *      Kernel thread context (may sleep).
1015  */
1016 void sata_pmp_error_handler(struct ata_port *ap)
1017 {
1018         ata_eh_autopsy(ap);
1019         ata_eh_report(ap);
1020         sata_pmp_eh_recover(ap);
1021         ata_eh_finish(ap);
1022 }
1023
1024 EXPORT_SYMBOL_GPL(sata_pmp_port_ops);
1025 EXPORT_SYMBOL_GPL(sata_pmp_qc_defer_cmd_switch);
1026 EXPORT_SYMBOL_GPL(sata_pmp_error_handler);