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_RW_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_RW_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         if (print_info) {
 261                 ata_dev_printk(dev, KERN_INFO, "Port Multiplier %s, "
 262                                "0x%04x:0x%04x r%d, %d ports, feat 0x%x/0x%x\n",
 263                                sata_pmp_spec_rev_str(gscr),
 264                                sata_pmp_gscr_vendor(gscr),
 265                                sata_pmp_gscr_devid(gscr),
 266                                sata_pmp_gscr_rev(gscr),
 267                                nr_ports, gscr[SATA_PMP_GSCR_FEAT_EN],
 268                                gscr[SATA_PMP_GSCR_FEAT]);
 269
 270                 if (!(dev->flags & ATA_DFLAG_AN))
 271                         ata_dev_printk(dev, KERN_INFO,
 272                                 "Asynchronous notification not supported, "
 273                                 "hotplug won't\n         work on fan-out "
 274                                 "ports. Use warm-plug instead.\n");
 275         }
 276
 277         return 0;
 278
 279  fail:
 280         ata_dev_printk(dev, KERN_ERR,
 281                        "failed to configure Port Multiplier (%s, Emask=0x%x)\n",
 282                        reason, err_mask);
 283         return rc;
 284 }
 285
 286 static int sata_pmp_init_links(struct ata_port *ap, int nr_ports)
 287 {
 288         struct ata_link *pmp_link = ap->pmp_link;
 289         int i;
 290
 291         if (!pmp_link) {
 292                 pmp_link = kzalloc(sizeof(pmp_link[0]) * SATA_PMP_MAX_PORTS,
 293                                    GFP_NOIO);
 294                 if (!pmp_link)
 295                         return -ENOMEM;
 296
 297                 for (i = 0; i < SATA_PMP_MAX_PORTS; i++)
 298                         ata_link_init(ap, &pmp_link[i], i);
 299
 300                 ap->pmp_link = pmp_link;
 301         }
 302
 303         for (i = 0; i < nr_ports; i++) {
 304                 struct ata_link *link = &pmp_link[i];
 305                 struct ata_eh_context *ehc = &link->eh_context;
 306
 307                 link->flags = 0;
 308                 ehc->i.probe_mask |= ATA_ALL_DEVICES;
 309                 ehc->i.action |= ATA_EH_RESET;
 310         }
 311
 312         return 0;
 313 }
 314
 315 static void sata_pmp_quirks(struct ata_port *ap)
 316 {
 317         u32 *gscr = ap->link.device->gscr;
 318         u16 vendor = sata_pmp_gscr_vendor(gscr);
 319         u16 devid = sata_pmp_gscr_devid(gscr);
 320         struct ata_link *link;
 321
 322         if (vendor == 0x1095 && devid == 0x3726) {
 323                 /* sil3726 quirks */
 324                 ata_for_each_link(link, ap, EDGE) {
 325                         /* Class code report is unreliable and SRST
 326                          * times out under certain configurations.
 327                          */
 328                         if (link->pmp < 5)
 329                                 link->flags |= ATA_LFLAG_NO_SRST |
 330                                                ATA_LFLAG_ASSUME_ATA;
 331
 332                         /* port 5 is for SEMB device and it doesn't like SRST */
 333                         if (link->pmp == 5)
 334                                 link->flags |= ATA_LFLAG_NO_SRST |
 335                                                ATA_LFLAG_ASSUME_SEMB;
 336                 }
 337         } else if (vendor == 0x1095 && devid == 0x4723) {
 338                 /* sil4723 quirks */
 339                 ata_for_each_link(link, ap, EDGE) {
 340                         /* class code report is unreliable */
 341                         if (link->pmp < 2)
 342                                 link->flags |= ATA_LFLAG_ASSUME_ATA;
 343
 344                         /* the config device at port 2 locks up on SRST */
 345                         if (link->pmp == 2)
 346                                 link->flags |= ATA_LFLAG_NO_SRST |
 347                                                ATA_LFLAG_ASSUME_ATA;
 348                 }
 349         } else if (vendor == 0x1095 && devid == 0x4726) {
 350                 /* sil4726 quirks */
 351                 ata_for_each_link(link, ap, EDGE) {
 352                         /* Class code report is unreliable and SRST
 353                          * times out under certain configurations.
 354                          * Config device can be at port 0 or 5 and
 355                          * locks up on SRST.
 356                          */
 357                         if (link->pmp <= 5)
 358                                 link->flags |= ATA_LFLAG_NO_SRST |
 359                                                ATA_LFLAG_ASSUME_ATA;
 360
 361                         /* Port 6 is for SEMB device which doesn't
 362                          * like SRST either.
 363                          */
 364                         if (link->pmp == 6)
 365                                 link->flags |= ATA_LFLAG_NO_SRST |
 366                                                ATA_LFLAG_ASSUME_SEMB;
 367                 }
 368         } else if (vendor == 0x1095 && (devid == 0x5723 || devid == 0x5733 ||
 369                                         devid == 0x5734 || devid == 0x5744)) {
 370                 /* sil5723/5744 quirks */
 371
 372                 /* sil5723/5744 has either two or three downstream
 373                  * ports depending on operation mode.  The last port
 374                  * is empty if any actual IO device is available or
 375                  * occupied by a pseudo configuration device
 376                  * otherwise.  Don't try hard to recover it.
 377                  */
 378                 ap->pmp_link[ap->nr_pmp_links - 1].flags |= ATA_LFLAG_NO_RETRY;
 379         }
 380 }
 381
 382 /**
 383  *      sata_pmp_attach - attach a SATA PMP device
 384  *      @dev: SATA PMP device to attach
 385  *
 386  *      Configure and attach SATA PMP device @dev.  This function is
 387  *      also responsible for allocating and initializing PMP links.
 388  *
 389  *      LOCKING:
 390  *      Kernel thread context (may sleep).
 391  *
 392  *      RETURNS:
 393  *      0 on success, -errno on failure.
 394  */
 395 int sata_pmp_attach(struct ata_device *dev)
 396 {
 397         struct ata_link *link = dev->link;
 398         struct ata_port *ap = link->ap;
 399         unsigned long flags;
 400         struct ata_link *tlink;
 401         int rc;
 402
 403         /* is it hanging off the right place? */
 404         if (!sata_pmp_supported(ap)) {
 405                 ata_dev_printk(dev, KERN_ERR,
 406                                "host does not support Port Multiplier\n");
 407                 return -EINVAL;
 408         }
 409
 410         if (!ata_is_host_link(link)) {
 411                 ata_dev_printk(dev, KERN_ERR,
 412                                "Port Multipliers cannot be nested\n");
 413                 return -EINVAL;
 414         }
 415
 416         if (dev->devno) {
 417                 ata_dev_printk(dev, KERN_ERR,
 418                                "Port Multiplier must be the first device\n");
 419                 return -EINVAL;
 420         }
 421
 422         WARN_ON(link->pmp != 0);
 423         link->pmp = SATA_PMP_CTRL_PORT;
 424
 425         /* read GSCR block */
 426         rc = sata_pmp_read_gscr(dev, dev->gscr);
 427         if (rc)
 428                 goto fail;
 429
 430         /* config PMP */
 431         rc = sata_pmp_configure(dev, 1);
 432         if (rc)
 433                 goto fail;
 434
 435         rc = sata_pmp_init_links(ap, sata_pmp_gscr_ports(dev->gscr));
 436         if (rc) {
 437                 ata_dev_printk(dev, KERN_INFO,
 438                                "failed to initialize PMP links\n");
 439                 goto fail;
 440         }
 441
 442         /* attach it */
 443         spin_lock_irqsave(ap->lock, flags);
 444         WARN_ON(ap->nr_pmp_links);
 445         ap->nr_pmp_links = sata_pmp_gscr_ports(dev->gscr);
 446         spin_unlock_irqrestore(ap->lock, flags);
 447
 448         sata_pmp_quirks(ap);
 449
 450         if (ap->ops->pmp_attach)
 451                 ap->ops->pmp_attach(ap);
 452
 453         ata_for_each_link(tlink, ap, EDGE)
 454                 sata_link_init_spd(tlink);
 455
 456         ata_acpi_associate_sata_port(ap);
 457
 458         return 0;
 459
 460  fail:
 461         link->pmp = 0;
 462         return rc;
 463 }
 464
 465 /**
 466  *      sata_pmp_detach - detach a SATA PMP device
 467  *      @dev: SATA PMP device to detach
 468  *
 469  *      Detach SATA PMP device @dev.  This function is also
 470  *      responsible for deconfiguring PMP links.
 471  *
 472  *      LOCKING:
 473  *      Kernel thread context (may sleep).
 474  */
 475 static void sata_pmp_detach(struct ata_device *dev)
 476 {
 477         struct ata_link *link = dev->link;
 478         struct ata_port *ap = link->ap;
 479         struct ata_link *tlink;
 480         unsigned long flags;
 481
 482         ata_dev_printk(dev, KERN_INFO, "Port Multiplier detaching\n");
 483
 484         WARN_ON(!ata_is_host_link(link) || dev->devno ||
 485                 link->pmp != SATA_PMP_CTRL_PORT);
 486
 487         if (ap->ops->pmp_detach)
 488                 ap->ops->pmp_detach(ap);
 489
 490         ata_for_each_link(tlink, ap, EDGE)
 491                 ata_eh_detach_dev(tlink->device);
 492
 493         spin_lock_irqsave(ap->lock, flags);
 494         ap->nr_pmp_links = 0;
 495         link->pmp = 0;
 496         spin_unlock_irqrestore(ap->lock, flags);
 497
 498         ata_acpi_associate_sata_port(ap);
 499 }
 500
 501 /**
 502  *      sata_pmp_same_pmp - does new GSCR matches the configured PMP?
 503  *      @dev: PMP device to compare against
 504  *      @new_gscr: GSCR block of the new device
 505  *
 506  *      Compare @new_gscr against @dev and determine whether @dev is
 507  *      the PMP described by @new_gscr.
 508  *
 509  *      LOCKING:
 510  *      None.
 511  *
 512  *      RETURNS:
 513  *      1 if @dev matches @new_gscr, 0 otherwise.
 514  */
 515 static int sata_pmp_same_pmp(struct ata_device *dev, const u32 *new_gscr)
 516 {
 517         const u32 *old_gscr = dev->gscr;
 518         u16 old_vendor, new_vendor, old_devid, new_devid;
 519         int old_nr_ports, new_nr_ports;
 520
 521         old_vendor = sata_pmp_gscr_vendor(old_gscr);
 522         new_vendor = sata_pmp_gscr_vendor(new_gscr);
 523         old_devid = sata_pmp_gscr_devid(old_gscr);
 524         new_devid = sata_pmp_gscr_devid(new_gscr);
 525         old_nr_ports = sata_pmp_gscr_ports(old_gscr);
 526         new_nr_ports = sata_pmp_gscr_ports(new_gscr);
 527
 528         if (old_vendor != new_vendor) {
 529                 ata_dev_printk(dev, KERN_INFO, "Port Multiplier "
 530                                "vendor mismatch '0x%x' != '0x%x'\n",
 531                                old_vendor, new_vendor);
 532                 return 0;
 533         }
 534
 535         if (old_devid != new_devid) {
 536                 ata_dev_printk(dev, KERN_INFO, "Port Multiplier "
 537                                "device ID mismatch '0x%x' != '0x%x'\n",
 538                                old_devid, new_devid);
 539                 return 0;
 540         }
 541
 542         if (old_nr_ports != new_nr_ports) {
 543                 ata_dev_printk(dev, KERN_INFO, "Port Multiplier "
 544                                "nr_ports mismatch '0x%x' != '0x%x'\n",
 545                                old_nr_ports, new_nr_ports);
 546                 return 0;
 547         }
 548
 549         return 1;
 550 }
 551
 552 /**
 553  *      sata_pmp_revalidate - revalidate SATA PMP
 554  *      @dev: PMP device to revalidate
 555  *      @new_class: new class code
 556  *
 557  *      Re-read GSCR block and make sure @dev is still attached to the
 558  *      port and properly configured.
 559  *
 560  *      LOCKING:
 561  *      Kernel thread context (may sleep).
 562  *
 563  *      RETURNS:
 564  *      0 on success, -errno otherwise.
 565  */
 566 static int sata_pmp_revalidate(struct ata_device *dev, unsigned int new_class)
 567 {
 568         struct ata_link *link = dev->link;
 569         struct ata_port *ap = link->ap;
 570         u32 *gscr = (void *)ap->sector_buf;
 571         int rc;
 572
 573         DPRINTK("ENTER\n");
 574
 575         ata_eh_about_to_do(link, NULL, ATA_EH_REVALIDATE);
 576
 577         if (!ata_dev_enabled(dev)) {
 578                 rc = -ENODEV;
 579                 goto fail;
 580         }
 581
 582         /* wrong class? */
 583         if (ata_class_enabled(new_class) && new_class != ATA_DEV_PMP) {
 584                 rc = -ENODEV;
 585                 goto fail;
 586         }
 587
 588         /* read GSCR */
 589         rc = sata_pmp_read_gscr(dev, gscr);
 590         if (rc)
 591                 goto fail;
 592
 593         /* is the pmp still there? */
 594         if (!sata_pmp_same_pmp(dev, gscr)) {
 595                 rc = -ENODEV;
 596                 goto fail;
 597         }
 598
 599         memcpy(dev->gscr, gscr, sizeof(gscr[0]) * SATA_PMP_GSCR_DWORDS);
 600
 601         rc = sata_pmp_configure(dev, 0);
 602         if (rc)
 603                 goto fail;
 604
 605         ata_eh_done(link, NULL, ATA_EH_REVALIDATE);
 606
 607         DPRINTK("EXIT, rc=0\n");
 608         return 0;
 609
 610  fail:
 611         ata_dev_printk(dev, KERN_ERR,
 612                        "PMP revalidation failed (errno=%d)\n", rc);
 613         DPRINTK("EXIT, rc=%d\n", rc);
 614         return rc;
 615 }
 616
 617 /**
 618  *      sata_pmp_revalidate_quick - revalidate SATA PMP quickly
 619  *      @dev: PMP device to revalidate
 620  *
 621  *      Make sure the attached PMP is accessible.
 622  *
 623  *      LOCKING:
 624  *      Kernel thread context (may sleep).
 625  *
 626  *      RETURNS:
 627  *      0 on success, -errno otherwise.
 628  */
 629 static int sata_pmp_revalidate_quick(struct ata_device *dev)
 630 {
 631         unsigned int err_mask;
 632         u32 prod_id;
 633
 634         err_mask = sata_pmp_read(dev->link, SATA_PMP_GSCR_PROD_ID, &prod_id);
 635         if (err_mask) {
 636                 ata_dev_printk(dev, KERN_ERR, "failed to read PMP product ID "
 637                                "(Emask=0x%x)\n", err_mask);
 638                 return -EIO;
 639         }
 640
 641         if (prod_id != dev->gscr[SATA_PMP_GSCR_PROD_ID]) {
 642                 ata_dev_printk(dev, KERN_ERR, "PMP product ID mismatch\n");
 643                 /* something weird is going on, request full PMP recovery */
 644                 return -EIO;
 645         }
 646
 647         return 0;
 648 }
 649
 650 /**
 651  *      sata_pmp_eh_recover_pmp - recover PMP
 652  *      @ap: ATA port PMP is attached to
 653  *      @prereset: prereset method (can be NULL)
 654  *      @softreset: softreset method
 655  *      @hardreset: hardreset method
 656  *      @postreset: postreset method (can be NULL)
 657  *
 658  *      Recover PMP attached to @ap.  Recovery procedure is somewhat
 659  *      similar to that of ata_eh_recover() except that reset should
 660  *      always be performed in hard->soft sequence and recovery
 661  *      failure results in PMP detachment.
 662  *
 663  *      LOCKING:
 664  *      Kernel thread context (may sleep).
 665  *
 666  *      RETURNS:
 667  *      0 on success, -errno on failure.
 668  */
 669 static int sata_pmp_eh_recover_pmp(struct ata_port *ap,
 670                 ata_prereset_fn_t prereset, ata_reset_fn_t softreset,
 671                 ata_reset_fn_t hardreset, ata_postreset_fn_t postreset)
 672 {
 673         struct ata_link *link = &ap->link;
 674         struct ata_eh_context *ehc = &link->eh_context;
 675         struct ata_device *dev = link->device;
 676         int tries = ATA_EH_PMP_TRIES;
 677         int detach = 0, rc = 0;
 678         int reval_failed = 0;
 679
 680         DPRINTK("ENTER\n");
 681
 682         if (dev->flags & ATA_DFLAG_DETACH) {
 683                 detach = 1;
 684                 goto fail;
 685         }
 686
 687  retry:
 688         ehc->classes[0] = ATA_DEV_UNKNOWN;
 689
 690         if (ehc->i.action & ATA_EH_RESET) {
 691                 struct ata_link *tlink;
 692
 693                 /* reset */
 694                 rc = ata_eh_reset(link, 0, prereset, softreset, hardreset,
 695                                   postreset);
 696                 if (rc) {
 697                         ata_link_printk(link, KERN_ERR,
 698                                         "failed to reset PMP, giving up\n");
 699                         goto fail;
 700                 }
 701
 702                 /* PMP is reset, SErrors cannot be trusted, scan all */
 703                 ata_for_each_link(tlink, ap, EDGE) {
 704                         struct ata_eh_context *ehc = &tlink->eh_context;
 705
 706                         ehc->i.probe_mask |= ATA_ALL_DEVICES;
 707                         ehc->i.action |= ATA_EH_RESET;
 708                 }
 709         }
 710
 711         /* If revalidation is requested, revalidate and reconfigure;
 712          * otherwise, do quick revalidation.
 713          */
 714         if (ehc->i.action & ATA_EH_REVALIDATE)
 715                 rc = sata_pmp_revalidate(dev, ehc->classes[0]);
 716         else
 717                 rc = sata_pmp_revalidate_quick(dev);
 718
 719         if (rc) {
 720                 tries--;
 721
 722                 if (rc == -ENODEV) {
 723                         ehc->i.probe_mask |= ATA_ALL_DEVICES;
 724                         detach = 1;
 725                         /* give it just two more chances */
 726                         tries = min(tries, 2);
 727                 }
 728
 729                 if (tries) {
 730                         /* consecutive revalidation failures? speed down */
 731                         if (reval_failed)
 732                                 sata_down_spd_limit(link);
 733                         else
 734                                 reval_failed = 1;
 735
 736                         ehc->i.action |= ATA_EH_RESET;
 737                         goto retry;
 738                 } else {
 739                         ata_dev_printk(dev, KERN_ERR, "failed to recover PMP "
 740                                        "after %d tries, giving up\n",
 741                                        ATA_EH_PMP_TRIES);
 742                         goto fail;
 743                 }
 744         }
 745
 746         /* okay, PMP resurrected */
 747         ehc->i.flags = 0;
 748
 749         DPRINTK("EXIT, rc=0\n");
 750         return 0;
 751
 752  fail:
 753         sata_pmp_detach(dev);
 754         if (detach)
 755                 ata_eh_detach_dev(dev);
 756         else
 757                 ata_dev_disable(dev);
 758
 759         DPRINTK("EXIT, rc=%d\n", rc);
 760         return rc;
 761 }
 762
 763 static int sata_pmp_eh_handle_disabled_links(struct ata_port *ap)
 764 {
 765         struct ata_link *link;
 766         unsigned long flags;
 767         int rc;
 768
 769         spin_lock_irqsave(ap->lock, flags);
 770
 771         ata_for_each_link(link, ap, EDGE) {
 772                 if (!(link->flags & ATA_LFLAG_DISABLED))
 773                         continue;
 774
 775                 spin_unlock_irqrestore(ap->lock, flags);
 776
 777                 /* Some PMPs require hardreset sequence to get
 778                  * SError.N working.
 779                  */
 780                 sata_link_hardreset(link, sata_deb_timing_normal,
 781                                 ata_deadline(jiffies, ATA_TMOUT_INTERNAL_QUICK),
 782                                 NULL, NULL);
 783
 784                 /* unconditionally clear SError.N */
 785                 rc = sata_scr_write(link, SCR_ERROR, SERR_PHYRDY_CHG);
 786                 if (rc) {
 787                         ata_link_printk(link, KERN_ERR, "failed to clear "
 788                                         "SError.N (errno=%d)\n", rc);
 789                         return rc;
 790                 }
 791
 792                 spin_lock_irqsave(ap->lock, flags);
 793         }
 794
 795         spin_unlock_irqrestore(ap->lock, flags);
 796
 797         return 0;
 798 }
 799
 800 static int sata_pmp_handle_link_fail(struct ata_link *link, int *link_tries)
 801 {
 802         struct ata_port *ap = link->ap;
 803         unsigned long flags;
 804
 805         if (link_tries[link->pmp] && --link_tries[link->pmp])
 806                 return 1;
 807
 808         /* disable this link */
 809         if (!(link->flags & ATA_LFLAG_DISABLED)) {
 810                 ata_link_printk(link, KERN_WARNING,
 811                         "failed to recover link after %d tries, disabling\n",
 812                         ATA_EH_PMP_LINK_TRIES);
 813
 814                 spin_lock_irqsave(ap->lock, flags);
 815                 link->flags |= ATA_LFLAG_DISABLED;
 816                 spin_unlock_irqrestore(ap->lock, flags);
 817         }
 818
 819         ata_dev_disable(link->device);
 820         link->eh_context.i.action = 0;
 821
 822         return 0;
 823 }
 824
 825 /**
 826  *      sata_pmp_eh_recover - recover PMP-enabled port
 827  *      @ap: ATA port to recover
 828  *
 829  *      Drive EH recovery operation for PMP enabled port @ap.  This
 830  *      function recovers host and PMP ports with proper retrials and
 831  *      fallbacks.  Actual recovery operations are performed using
 832  *      ata_eh_recover() and sata_pmp_eh_recover_pmp().
 833  *
 834  *      LOCKING:
 835  *      Kernel thread context (may sleep).
 836  *
 837  *      RETURNS:
 838  *      0 on success, -errno on failure.
 839  */
 840 static int sata_pmp_eh_recover(struct ata_port *ap)
 841 {
 842         struct ata_port_operations *ops = ap->ops;
 843         int pmp_tries, link_tries[SATA_PMP_MAX_PORTS];
 844         struct ata_link *pmp_link = &ap->link;
 845         struct ata_device *pmp_dev = pmp_link->device;
 846         struct ata_eh_context *pmp_ehc = &pmp_link->eh_context;
 847         u32 *gscr = pmp_dev->gscr;
 848         struct ata_link *link;
 849         struct ata_device *dev;
 850         unsigned int err_mask;
 851         u32 gscr_error, sntf;
 852         int cnt, rc;
 853
 854         pmp_tries = ATA_EH_PMP_TRIES;
 855         ata_for_each_link(link, ap, EDGE)
 856                 link_tries[link->pmp] = ATA_EH_PMP_LINK_TRIES;
 857
 858  retry:
 859         /* PMP attached? */
 860         if (!sata_pmp_attached(ap)) {
 861                 rc = ata_eh_recover(ap, ops->prereset, ops->softreset,
 862                                     ops->hardreset, ops->postreset, NULL);
 863                 if (rc) {
 864                         ata_for_each_dev(dev, &ap->link, ALL)
 865                                 ata_dev_disable(dev);
 866                         return rc;
 867                 }
 868
 869                 if (pmp_dev->class != ATA_DEV_PMP)
 870                         return 0;
 871
 872                 /* new PMP online */
 873                 ata_for_each_link(link, ap, EDGE)
 874                         link_tries[link->pmp] = ATA_EH_PMP_LINK_TRIES;
 875
 876                 /* fall through */
 877         }
 878
 879         /* recover pmp */
 880         rc = sata_pmp_eh_recover_pmp(ap, ops->prereset, ops->softreset,
 881                                      ops->hardreset, ops->postreset);
 882         if (rc)
 883                 goto pmp_fail;
 884
 885         /* PHY event notification can disturb reset and other recovery
 886          * operations.  Turn it off.
 887          */
 888         if (gscr[SATA_PMP_GSCR_FEAT_EN] & SATA_PMP_FEAT_NOTIFY) {
 889                 gscr[SATA_PMP_GSCR_FEAT_EN] &= ~SATA_PMP_FEAT_NOTIFY;
 890
 891                 err_mask = sata_pmp_write(pmp_link, SATA_PMP_GSCR_FEAT_EN,
 892                                           gscr[SATA_PMP_GSCR_FEAT_EN]);
 893                 if (err_mask) {
 894                         ata_link_printk(pmp_link, KERN_WARNING,
 895                                 "failed to disable NOTIFY (err_mask=0x%x)\n",
 896                                 err_mask);
 897                         goto pmp_fail;
 898                 }
 899         }
 900
 901         /* handle disabled links */
 902         rc = sata_pmp_eh_handle_disabled_links(ap);
 903         if (rc)
 904                 goto pmp_fail;
 905
 906         /* recover links */
 907         rc = ata_eh_recover(ap, ops->pmp_prereset, ops->pmp_softreset,
 908                             ops->pmp_hardreset, ops->pmp_postreset, &link);
 909         if (rc)
 910                 goto link_fail;
 911
 912         /* Connection status might have changed while resetting other
 913          * links, check SATA_PMP_GSCR_ERROR before returning.
 914          */
 915
 916         /* clear SNotification */
 917         rc = sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf);
 918         if (rc == 0)
 919                 sata_scr_write(&ap->link, SCR_NOTIFICATION, sntf);
 920
 921         /* enable notification */
 922         if (pmp_dev->flags & ATA_DFLAG_AN) {
 923                 gscr[SATA_PMP_GSCR_FEAT_EN] |= SATA_PMP_FEAT_NOTIFY;
 924
 925                 err_mask = sata_pmp_write(pmp_link, SATA_PMP_GSCR_FEAT_EN,
 926                                           gscr[SATA_PMP_GSCR_FEAT_EN]);
 927                 if (err_mask) {
 928                         ata_dev_printk(pmp_dev, KERN_ERR, "failed to write "
 929                                        "PMP_FEAT_EN (Emask=0x%x)\n", err_mask);
 930                         rc = -EIO;
 931                         goto pmp_fail;
 932                 }
 933         }
 934
 935         /* check GSCR_ERROR */
 936         err_mask = sata_pmp_read(pmp_link, SATA_PMP_GSCR_ERROR, &gscr_error);
 937         if (err_mask) {
 938                 ata_dev_printk(pmp_dev, KERN_ERR, "failed to read "
 939                                "PMP_GSCR_ERROR (Emask=0x%x)\n", err_mask);
 940                 rc = -EIO;
 941                 goto pmp_fail;
 942         }
 943
 944         cnt = 0;
 945         ata_for_each_link(link, ap, EDGE) {
 946                 if (!(gscr_error & (1 << link->pmp)))
 947                         continue;
 948
 949                 if (sata_pmp_handle_link_fail(link, link_tries)) {
 950                         ata_ehi_hotplugged(&link->eh_context.i);
 951                         cnt++;
 952                 } else {
 953                         ata_link_printk(link, KERN_WARNING,
 954                                 "PHY status changed but maxed out on retries, "
 955                                 "giving up\n");
 956                         ata_link_printk(link, KERN_WARNING,
 957                                 "Manully issue scan to resume this link\n");
 958                 }
 959         }
 960
 961         if (cnt) {
 962                 ata_port_printk(ap, KERN_INFO, "PMP SError.N set for some "
 963                                 "ports, repeating recovery\n");
 964                 goto retry;
 965         }
 966
 967         return 0;
 968
 969  link_fail:
 970         if (sata_pmp_handle_link_fail(link, link_tries)) {
 971                 pmp_ehc->i.action |= ATA_EH_RESET;
 972                 goto retry;
 973         }
 974
 975         /* fall through */
 976  pmp_fail:
 977         /* Control always ends up here after detaching PMP.  Shut up
 978          * and return if we're unloading.
 979          */
 980         if (ap->pflags & ATA_PFLAG_UNLOADING)
 981                 return rc;
 982
 983         if (!sata_pmp_attached(ap))
 984                 goto retry;
 985
 986         if (--pmp_tries) {
 987                 pmp_ehc->i.action |= ATA_EH_RESET;
 988                 goto retry;
 989         }
 990
 991         ata_port_printk(ap, KERN_ERR,
 992                         "failed to recover PMP after %d tries, giving up\n",
 993                         ATA_EH_PMP_TRIES);
 994         sata_pmp_detach(pmp_dev);
 995         ata_dev_disable(pmp_dev);
 996
 997         return rc;
 998 }
 999
1000 /**
1001  *      sata_pmp_error_handler - do standard error handling for PMP-enabled host
1002  *      @ap: host port to handle error for
1003  *
1004  *      Perform standard error handling sequence for PMP-enabled host
1005  *      @ap.
1006  *
1007  *      LOCKING:
1008  *      Kernel thread context (may sleep).
1009  */
1010 void sata_pmp_error_handler(struct ata_port *ap)
1011 {
1012         ata_eh_autopsy(ap);
1013         ata_eh_report(ap);
1014         sata_pmp_eh_recover(ap);
1015         ata_eh_finish(ap);
1016 }
1017
1018 EXPORT_SYMBOL_GPL(sata_pmp_port_ops);
1019 EXPORT_SYMBOL_GPL(sata_pmp_qc_defer_cmd_switch);
1020 EXPORT_SYMBOL_GPL(sata_pmp_error_handler);