linux/drivers/ata/libata-pmp.c
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   1// SPDX-License-Identifier: GPL-2.0-only
   2/*
   3 * libata-pmp.c - libata port multiplier support
   4 *
   5 * Copyright (c) 2007  SUSE Linux Products GmbH
   6 * Copyright (c) 2007  Tejun Heo <teheo@suse.de>
   7 */
   8
   9#include <linux/kernel.h>
  10#include <linux/export.h>
  11#include <linux/libata.h>
  12#include <linux/slab.h>
  13#include "libata.h"
  14#include "libata-transport.h"
  15
  16const struct ata_port_operations sata_pmp_port_ops = {
  17        .inherits               = &sata_port_ops,
  18        .pmp_prereset           = ata_std_prereset,
  19        .pmp_hardreset          = sata_std_hardreset,
  20        .pmp_postreset          = ata_std_postreset,
  21        .error_handler          = sata_pmp_error_handler,
  22};
  23
  24/**
  25 *      sata_pmp_read - read PMP register
  26 *      @link: link to read PMP register for
  27 *      @reg: register to read
  28 *      @r_val: resulting value
  29 *
  30 *      Read PMP register.
  31 *
  32 *      LOCKING:
  33 *      Kernel thread context (may sleep).
  34 *
  35 *      RETURNS:
  36 *      0 on success, AC_ERR_* mask on failure.
  37 */
  38static unsigned int sata_pmp_read(struct ata_link *link, int reg, u32 *r_val)
  39{
  40        struct ata_port *ap = link->ap;
  41        struct ata_device *pmp_dev = ap->link.device;
  42        struct ata_taskfile tf;
  43        unsigned int err_mask;
  44
  45        ata_tf_init(pmp_dev, &tf);
  46        tf.command = ATA_CMD_PMP_READ;
  47        tf.protocol = ATA_PROT_NODATA;
  48        tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_LBA48;
  49        tf.feature = reg;
  50        tf.device = link->pmp;
  51
  52        err_mask = ata_exec_internal(pmp_dev, &tf, NULL, DMA_NONE, NULL, 0,
  53                                     SATA_PMP_RW_TIMEOUT);
  54        if (err_mask)
  55                return err_mask;
  56
  57        *r_val = tf.nsect | tf.lbal << 8 | tf.lbam << 16 | tf.lbah << 24;
  58        return 0;
  59}
  60
  61/**
  62 *      sata_pmp_write - write PMP register
  63 *      @link: link to write PMP register for
  64 *      @reg: register to write
  65 *      @r_val: value to write
  66 *
  67 *      Write PMP register.
  68 *
  69 *      LOCKING:
  70 *      Kernel thread context (may sleep).
  71 *
  72 *      RETURNS:
  73 *      0 on success, AC_ERR_* mask on failure.
  74 */
  75static unsigned int sata_pmp_write(struct ata_link *link, int reg, u32 val)
  76{
  77        struct ata_port *ap = link->ap;
  78        struct ata_device *pmp_dev = ap->link.device;
  79        struct ata_taskfile tf;
  80
  81        ata_tf_init(pmp_dev, &tf);
  82        tf.command = ATA_CMD_PMP_WRITE;
  83        tf.protocol = ATA_PROT_NODATA;
  84        tf.flags |= ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE | ATA_TFLAG_LBA48;
  85        tf.feature = reg;
  86        tf.device = link->pmp;
  87        tf.nsect = val & 0xff;
  88        tf.lbal = (val >> 8) & 0xff;
  89        tf.lbam = (val >> 16) & 0xff;
  90        tf.lbah = (val >> 24) & 0xff;
  91
  92        return ata_exec_internal(pmp_dev, &tf, NULL, DMA_NONE, NULL, 0,
  93                                 SATA_PMP_RW_TIMEOUT);
  94}
  95
  96/**
  97 *      sata_pmp_qc_defer_cmd_switch - qc_defer for command switching PMP
  98 *      @qc: ATA command in question
  99 *
 100 *      A host which has command switching PMP support cannot issue
 101 *      commands to multiple links simultaneously.
 102 *
 103 *      LOCKING:
 104 *      spin_lock_irqsave(host lock)
 105 *
 106 *      RETURNS:
 107 *      ATA_DEFER_* if deferring is needed, 0 otherwise.
 108 */
 109int sata_pmp_qc_defer_cmd_switch(struct ata_queued_cmd *qc)
 110{
 111        struct ata_link *link = qc->dev->link;
 112        struct ata_port *ap = link->ap;
 113
 114        if (ap->excl_link == NULL || ap->excl_link == link) {
 115                if (ap->nr_active_links == 0 || ata_link_active(link)) {
 116                        qc->flags |= ATA_QCFLAG_CLEAR_EXCL;
 117                        return ata_std_qc_defer(qc);
 118                }
 119
 120                ap->excl_link = link;
 121        }
 122
 123        return ATA_DEFER_PORT;
 124}
 125
 126/**
 127 *      sata_pmp_scr_read - read PSCR
 128 *      @link: ATA link to read PSCR for
 129 *      @reg: PSCR to read
 130 *      @r_val: resulting value
 131 *
 132 *      Read PSCR @reg into @r_val for @link, to be called from
 133 *      ata_scr_read().
 134 *
 135 *      LOCKING:
 136 *      Kernel thread context (may sleep).
 137 *
 138 *      RETURNS:
 139 *      0 on success, -errno on failure.
 140 */
 141int sata_pmp_scr_read(struct ata_link *link, int reg, u32 *r_val)
 142{
 143        unsigned int err_mask;
 144
 145        if (reg > SATA_PMP_PSCR_CONTROL)
 146                return -EINVAL;
 147
 148        err_mask = sata_pmp_read(link, reg, r_val);
 149        if (err_mask) {
 150                ata_link_warn(link, "failed to read SCR %d (Emask=0x%x)\n",
 151                              reg, err_mask);
 152                return -EIO;
 153        }
 154        return 0;
 155}
 156
 157/**
 158 *      sata_pmp_scr_write - write PSCR
 159 *      @link: ATA link to write PSCR for
 160 *      @reg: PSCR to write
 161 *      @val: value to be written
 162 *
 163 *      Write @val to PSCR @reg for @link, to be called from
 164 *      ata_scr_write() and ata_scr_write_flush().
 165 *
 166 *      LOCKING:
 167 *      Kernel thread context (may sleep).
 168 *
 169 *      RETURNS:
 170 *      0 on success, -errno on failure.
 171 */
 172int sata_pmp_scr_write(struct ata_link *link, int reg, u32 val)
 173{
 174        unsigned int err_mask;
 175
 176        if (reg > SATA_PMP_PSCR_CONTROL)
 177                return -EINVAL;
 178
 179        err_mask = sata_pmp_write(link, reg, val);
 180        if (err_mask) {
 181                ata_link_warn(link, "failed to write SCR %d (Emask=0x%x)\n",
 182                              reg, err_mask);
 183                return -EIO;
 184        }
 185        return 0;
 186}
 187
 188/**
 189 *      sata_pmp_set_lpm - configure LPM for a PMP link
 190 *      @link: PMP link to configure LPM for
 191 *      @policy: target LPM policy
 192 *      @hints: LPM hints
 193 *
 194 *      Configure LPM for @link.  This function will contain any PMP
 195 *      specific workarounds if necessary.
 196 *
 197 *      LOCKING:
 198 *      EH context.
 199 *
 200 *      RETURNS:
 201 *      0 on success, -errno on failure.
 202 */
 203int sata_pmp_set_lpm(struct ata_link *link, enum ata_lpm_policy policy,
 204                     unsigned hints)
 205{
 206        return sata_link_scr_lpm(link, policy, true);
 207}
 208
 209/**
 210 *      sata_pmp_read_gscr - read GSCR block of SATA PMP
 211 *      @dev: PMP device
 212 *      @gscr: buffer to read GSCR block into
 213 *
 214 *      Read selected PMP GSCRs from the PMP at @dev.  This will serve
 215 *      as configuration and identification info for the PMP.
 216 *
 217 *      LOCKING:
 218 *      Kernel thread context (may sleep).
 219 *
 220 *      RETURNS:
 221 *      0 on success, -errno on failure.
 222 */
 223static int sata_pmp_read_gscr(struct ata_device *dev, u32 *gscr)
 224{
 225        static const int gscr_to_read[] = { 0, 1, 2, 32, 33, 64, 96 };
 226        int i;
 227
 228        for (i = 0; i < ARRAY_SIZE(gscr_to_read); i++) {
 229                int reg = gscr_to_read[i];
 230                unsigned int err_mask;
 231
 232                err_mask = sata_pmp_read(dev->link, reg, &gscr[reg]);
 233                if (err_mask) {
 234                        ata_dev_err(dev, "failed to read PMP GSCR[%d] (Emask=0x%x)\n",
 235                                    reg, err_mask);
 236                        return -EIO;
 237                }
 238        }
 239
 240        return 0;
 241}
 242
 243static const char *sata_pmp_spec_rev_str(const u32 *gscr)
 244{
 245        u32 rev = gscr[SATA_PMP_GSCR_REV];
 246
 247        if (rev & (1 << 3))
 248                return "1.2";
 249        if (rev & (1 << 2))
 250                return "1.1";
 251        if (rev & (1 << 1))
 252                return "1.0";
 253        return "<unknown>";
 254}
 255
 256#define PMP_GSCR_SII_POL 129
 257
 258static int sata_pmp_configure(struct ata_device *dev, int print_info)
 259{
 260        struct ata_port *ap = dev->link->ap;
 261        u32 *gscr = dev->gscr;
 262        u16 vendor = sata_pmp_gscr_vendor(gscr);
 263        u16 devid = sata_pmp_gscr_devid(gscr);
 264        unsigned int err_mask = 0;
 265        const char *reason;
 266        int nr_ports, rc;
 267
 268        nr_ports = sata_pmp_gscr_ports(gscr);
 269
 270        if (nr_ports <= 0 || nr_ports > SATA_PMP_MAX_PORTS) {
 271                rc = -EINVAL;
 272                reason = "invalid nr_ports";
 273                goto fail;
 274        }
 275
 276        if ((ap->flags & ATA_FLAG_AN) &&
 277            (gscr[SATA_PMP_GSCR_FEAT] & SATA_PMP_FEAT_NOTIFY))
 278                dev->flags |= ATA_DFLAG_AN;
 279
 280        /* monitor SERR_PHYRDY_CHG on fan-out ports */
 281        err_mask = sata_pmp_write(dev->link, SATA_PMP_GSCR_ERROR_EN,
 282                                  SERR_PHYRDY_CHG);
 283        if (err_mask) {
 284                rc = -EIO;
 285                reason = "failed to write GSCR_ERROR_EN";
 286                goto fail;
 287        }
 288
 289        /* Disable sending Early R_OK.
 290         * With "cached read" HDD testing and multiple ports busy on a SATA
 291         * host controller, 3x26 PMP will very rarely drop a deferred
 292         * R_OK that was intended for the host. Symptom will be all
 293         * 5 drives under test will timeout, get reset, and recover.
 294         */
 295        if (vendor == 0x1095 && (devid == 0x3726 || devid == 0x3826)) {
 296                u32 reg;
 297
 298                err_mask = sata_pmp_read(&ap->link, PMP_GSCR_SII_POL, &reg);
 299                if (err_mask) {
 300                        rc = -EIO;
 301                        reason = "failed to read Sil3x26 Private Register";
 302                        goto fail;
 303                }
 304                reg &= ~0x1;
 305                err_mask = sata_pmp_write(&ap->link, PMP_GSCR_SII_POL, reg);
 306                if (err_mask) {
 307                        rc = -EIO;
 308                        reason = "failed to write Sil3x26 Private Register";
 309                        goto fail;
 310                }
 311        }
 312
 313        if (print_info) {
 314                ata_dev_info(dev, "Port Multiplier %s, "
 315                             "0x%04x:0x%04x r%d, %d ports, feat 0x%x/0x%x\n",
 316                             sata_pmp_spec_rev_str(gscr), vendor, devid,
 317                             sata_pmp_gscr_rev(gscr),
 318                             nr_ports, gscr[SATA_PMP_GSCR_FEAT_EN],
 319                             gscr[SATA_PMP_GSCR_FEAT]);
 320
 321                if (!(dev->flags & ATA_DFLAG_AN))
 322                        ata_dev_info(dev,
 323                                "Asynchronous notification not supported, "
 324                                "hotplug won't work on fan-out ports. Use warm-plug instead.\n");
 325        }
 326
 327        return 0;
 328
 329 fail:
 330        ata_dev_err(dev,
 331                    "failed to configure Port Multiplier (%s, Emask=0x%x)\n",
 332                    reason, err_mask);
 333        return rc;
 334}
 335
 336static int sata_pmp_init_links (struct ata_port *ap, int nr_ports)
 337{
 338        struct ata_link *pmp_link = ap->pmp_link;
 339        int i, err;
 340
 341        if (!pmp_link) {
 342                pmp_link = kcalloc(SATA_PMP_MAX_PORTS, sizeof(pmp_link[0]),
 343                                   GFP_NOIO);
 344                if (!pmp_link)
 345                        return -ENOMEM;
 346
 347                for (i = 0; i < SATA_PMP_MAX_PORTS; i++)
 348                        ata_link_init(ap, &pmp_link[i], i);
 349
 350                ap->pmp_link = pmp_link;
 351
 352                for (i = 0; i < SATA_PMP_MAX_PORTS; i++) {
 353                        err = ata_tlink_add(&pmp_link[i]);
 354                        if (err) {
 355                                goto err_tlink;
 356                        }
 357                }
 358        }
 359
 360        for (i = 0; i < nr_ports; i++) {
 361                struct ata_link *link = &pmp_link[i];
 362                struct ata_eh_context *ehc = &link->eh_context;
 363
 364                link->flags = 0;
 365                ehc->i.probe_mask |= ATA_ALL_DEVICES;
 366                ehc->i.action |= ATA_EH_RESET;
 367        }
 368
 369        return 0;
 370  err_tlink:
 371        while (--i >= 0)
 372                ata_tlink_delete(&pmp_link[i]);
 373        kfree(pmp_link);
 374        ap->pmp_link = NULL;
 375        return err;
 376}
 377
 378static void sata_pmp_quirks(struct ata_port *ap)
 379{
 380        u32 *gscr = ap->link.device->gscr;
 381        u16 vendor = sata_pmp_gscr_vendor(gscr);
 382        u16 devid = sata_pmp_gscr_devid(gscr);
 383        struct ata_link *link;
 384
 385        if (vendor == 0x1095 && (devid == 0x3726 || devid == 0x3826)) {
 386                /* sil3x26 quirks */
 387                ata_for_each_link(link, ap, EDGE) {
 388                        /* link reports offline after LPM */
 389                        link->flags |= ATA_LFLAG_NO_LPM;
 390
 391                        /*
 392                         * Class code report is unreliable and SRST times
 393                         * out under certain configurations.
 394                         */
 395                        if (link->pmp < 5)
 396                                link->flags |= ATA_LFLAG_NO_SRST |
 397                                               ATA_LFLAG_ASSUME_ATA;
 398
 399                        /* port 5 is for SEMB device and it doesn't like SRST */
 400                        if (link->pmp == 5)
 401                                link->flags |= ATA_LFLAG_NO_SRST |
 402                                               ATA_LFLAG_ASSUME_SEMB;
 403                }
 404        } else if (vendor == 0x1095 && devid == 0x4723) {
 405                /*
 406                 * sil4723 quirks
 407                 *
 408                 * Link reports offline after LPM.  Class code report is
 409                 * unreliable.  SIMG PMPs never got SRST reliable and the
 410                 * config device at port 2 locks up on SRST.
 411                 */
 412                ata_for_each_link(link, ap, EDGE)
 413                        link->flags |= ATA_LFLAG_NO_LPM |
 414                                       ATA_LFLAG_NO_SRST |
 415                                       ATA_LFLAG_ASSUME_ATA;
 416        } else if (vendor == 0x1095 && devid == 0x4726) {
 417                /* sil4726 quirks */
 418                ata_for_each_link(link, ap, EDGE) {
 419                        /* link reports offline after LPM */
 420                        link->flags |= ATA_LFLAG_NO_LPM;
 421
 422                        /* Class code report is unreliable and SRST
 423                         * times out under certain configurations.
 424                         * Config device can be at port 0 or 5 and
 425                         * locks up on SRST.
 426                         */
 427                        if (link->pmp <= 5)
 428                                link->flags |= ATA_LFLAG_NO_SRST |
 429                                               ATA_LFLAG_ASSUME_ATA;
 430
 431                        /* Port 6 is for SEMB device which doesn't
 432                         * like SRST either.
 433                         */
 434                        if (link->pmp == 6)
 435                                link->flags |= ATA_LFLAG_NO_SRST |
 436                                               ATA_LFLAG_ASSUME_SEMB;
 437                }
 438        } else if (vendor == 0x1095 && (devid == 0x5723 || devid == 0x5733 ||
 439                                        devid == 0x5734 || devid == 0x5744)) {
 440                /* sil5723/5744 quirks */
 441
 442                /* sil5723/5744 has either two or three downstream
 443                 * ports depending on operation mode.  The last port
 444                 * is empty if any actual IO device is available or
 445                 * occupied by a pseudo configuration device
 446                 * otherwise.  Don't try hard to recover it.
 447                 */
 448                ap->pmp_link[ap->nr_pmp_links - 1].flags |= ATA_LFLAG_NO_RETRY;
 449        } else if (vendor == 0x197b && (devid == 0x2352 || devid == 0x0325)) {
 450                /*
 451                 * 0x2352: found in Thermaltake BlackX Duet, jmicron JMB350?
 452                 * 0x0325: jmicron JMB394.
 453                 */
 454                ata_for_each_link(link, ap, EDGE) {
 455                        /* SRST breaks detection and disks get misclassified
 456                         * LPM disabled to avoid potential problems
 457                         */
 458                        link->flags |= ATA_LFLAG_NO_LPM |
 459                                       ATA_LFLAG_NO_SRST |
 460                                       ATA_LFLAG_ASSUME_ATA;
 461                }
 462        } else if (vendor == 0x11ab && devid == 0x4140) {
 463                /* Marvell 4140 quirks */
 464                ata_for_each_link(link, ap, EDGE) {
 465                        /* port 4 is for SEMB device and it doesn't like SRST */
 466                        if (link->pmp == 4)
 467                                link->flags |= ATA_LFLAG_DISABLED;
 468                }
 469        }
 470}
 471
 472/**
 473 *      sata_pmp_attach - attach a SATA PMP device
 474 *      @dev: SATA PMP device to attach
 475 *
 476 *      Configure and attach SATA PMP device @dev.  This function is
 477 *      also responsible for allocating and initializing PMP links.
 478 *
 479 *      LOCKING:
 480 *      Kernel thread context (may sleep).
 481 *
 482 *      RETURNS:
 483 *      0 on success, -errno on failure.
 484 */
 485int sata_pmp_attach(struct ata_device *dev)
 486{
 487        struct ata_link *link = dev->link;
 488        struct ata_port *ap = link->ap;
 489        unsigned long flags;
 490        struct ata_link *tlink;
 491        int rc;
 492
 493        /* is it hanging off the right place? */
 494        if (!sata_pmp_supported(ap)) {
 495                ata_dev_err(dev, "host does not support Port Multiplier\n");
 496                return -EINVAL;
 497        }
 498
 499        if (!ata_is_host_link(link)) {
 500                ata_dev_err(dev, "Port Multipliers cannot be nested\n");
 501                return -EINVAL;
 502        }
 503
 504        if (dev->devno) {
 505                ata_dev_err(dev, "Port Multiplier must be the first device\n");
 506                return -EINVAL;
 507        }
 508
 509        WARN_ON(link->pmp != 0);
 510        link->pmp = SATA_PMP_CTRL_PORT;
 511
 512        /* read GSCR block */
 513        rc = sata_pmp_read_gscr(dev, dev->gscr);
 514        if (rc)
 515                goto fail;
 516
 517        /* config PMP */
 518        rc = sata_pmp_configure(dev, 1);
 519        if (rc)
 520                goto fail;
 521
 522        rc = sata_pmp_init_links(ap, sata_pmp_gscr_ports(dev->gscr));
 523        if (rc) {
 524                ata_dev_info(dev, "failed to initialize PMP links\n");
 525                goto fail;
 526        }
 527
 528        /* attach it */
 529        spin_lock_irqsave(ap->lock, flags);
 530        WARN_ON(ap->nr_pmp_links);
 531        ap->nr_pmp_links = sata_pmp_gscr_ports(dev->gscr);
 532        spin_unlock_irqrestore(ap->lock, flags);
 533
 534        sata_pmp_quirks(ap);
 535
 536        if (ap->ops->pmp_attach)
 537                ap->ops->pmp_attach(ap);
 538
 539        ata_for_each_link(tlink, ap, EDGE)
 540                sata_link_init_spd(tlink);
 541
 542        return 0;
 543
 544 fail:
 545        link->pmp = 0;
 546        return rc;
 547}
 548
 549/**
 550 *      sata_pmp_detach - detach a SATA PMP device
 551 *      @dev: SATA PMP device to detach
 552 *
 553 *      Detach SATA PMP device @dev.  This function is also
 554 *      responsible for deconfiguring PMP links.
 555 *
 556 *      LOCKING:
 557 *      Kernel thread context (may sleep).
 558 */
 559static void sata_pmp_detach(struct ata_device *dev)
 560{
 561        struct ata_link *link = dev->link;
 562        struct ata_port *ap = link->ap;
 563        struct ata_link *tlink;
 564        unsigned long flags;
 565
 566        ata_dev_info(dev, "Port Multiplier detaching\n");
 567
 568        WARN_ON(!ata_is_host_link(link) || dev->devno ||
 569                link->pmp != SATA_PMP_CTRL_PORT);
 570
 571        if (ap->ops->pmp_detach)
 572                ap->ops->pmp_detach(ap);
 573
 574        ata_for_each_link(tlink, ap, EDGE)
 575                ata_eh_detach_dev(tlink->device);
 576
 577        spin_lock_irqsave(ap->lock, flags);
 578        ap->nr_pmp_links = 0;
 579        link->pmp = 0;
 580        spin_unlock_irqrestore(ap->lock, flags);
 581}
 582
 583/**
 584 *      sata_pmp_same_pmp - does new GSCR matches the configured PMP?
 585 *      @dev: PMP device to compare against
 586 *      @new_gscr: GSCR block of the new device
 587 *
 588 *      Compare @new_gscr against @dev and determine whether @dev is
 589 *      the PMP described by @new_gscr.
 590 *
 591 *      LOCKING:
 592 *      None.
 593 *
 594 *      RETURNS:
 595 *      1 if @dev matches @new_gscr, 0 otherwise.
 596 */
 597static int sata_pmp_same_pmp(struct ata_device *dev, const u32 *new_gscr)
 598{
 599        const u32 *old_gscr = dev->gscr;
 600        u16 old_vendor, new_vendor, old_devid, new_devid;
 601        int old_nr_ports, new_nr_ports;
 602
 603        old_vendor = sata_pmp_gscr_vendor(old_gscr);
 604        new_vendor = sata_pmp_gscr_vendor(new_gscr);
 605        old_devid = sata_pmp_gscr_devid(old_gscr);
 606        new_devid = sata_pmp_gscr_devid(new_gscr);
 607        old_nr_ports = sata_pmp_gscr_ports(old_gscr);
 608        new_nr_ports = sata_pmp_gscr_ports(new_gscr);
 609
 610        if (old_vendor != new_vendor) {
 611                ata_dev_info(dev,
 612                             "Port Multiplier vendor mismatch '0x%x' != '0x%x'\n",
 613                             old_vendor, new_vendor);
 614                return 0;
 615        }
 616
 617        if (old_devid != new_devid) {
 618                ata_dev_info(dev,
 619                             "Port Multiplier device ID mismatch '0x%x' != '0x%x'\n",
 620                             old_devid, new_devid);
 621                return 0;
 622        }
 623
 624        if (old_nr_ports != new_nr_ports) {
 625                ata_dev_info(dev,
 626                             "Port Multiplier nr_ports mismatch '0x%x' != '0x%x'\n",
 627                             old_nr_ports, new_nr_ports);
 628                return 0;
 629        }
 630
 631        return 1;
 632}
 633
 634/**
 635 *      sata_pmp_revalidate - revalidate SATA PMP
 636 *      @dev: PMP device to revalidate
 637 *      @new_class: new class code
 638 *
 639 *      Re-read GSCR block and make sure @dev is still attached to the
 640 *      port and properly configured.
 641 *
 642 *      LOCKING:
 643 *      Kernel thread context (may sleep).
 644 *
 645 *      RETURNS:
 646 *      0 on success, -errno otherwise.
 647 */
 648static int sata_pmp_revalidate(struct ata_device *dev, unsigned int new_class)
 649{
 650        struct ata_link *link = dev->link;
 651        struct ata_port *ap = link->ap;
 652        u32 *gscr = (void *)ap->sector_buf;
 653        int rc;
 654
 655        DPRINTK("ENTER\n");
 656
 657        ata_eh_about_to_do(link, NULL, ATA_EH_REVALIDATE);
 658
 659        if (!ata_dev_enabled(dev)) {
 660                rc = -ENODEV;
 661                goto fail;
 662        }
 663
 664        /* wrong class? */
 665        if (ata_class_enabled(new_class) && new_class != ATA_DEV_PMP) {
 666                rc = -ENODEV;
 667                goto fail;
 668        }
 669
 670        /* read GSCR */
 671        rc = sata_pmp_read_gscr(dev, gscr);
 672        if (rc)
 673                goto fail;
 674
 675        /* is the pmp still there? */
 676        if (!sata_pmp_same_pmp(dev, gscr)) {
 677                rc = -ENODEV;
 678                goto fail;
 679        }
 680
 681        memcpy(dev->gscr, gscr, sizeof(gscr[0]) * SATA_PMP_GSCR_DWORDS);
 682
 683        rc = sata_pmp_configure(dev, 0);
 684        if (rc)
 685                goto fail;
 686
 687        ata_eh_done(link, NULL, ATA_EH_REVALIDATE);
 688
 689        DPRINTK("EXIT, rc=0\n");
 690        return 0;
 691
 692 fail:
 693        ata_dev_err(dev, "PMP revalidation failed (errno=%d)\n", rc);
 694        DPRINTK("EXIT, rc=%d\n", rc);
 695        return rc;
 696}
 697
 698/**
 699 *      sata_pmp_revalidate_quick - revalidate SATA PMP quickly
 700 *      @dev: PMP device to revalidate
 701 *
 702 *      Make sure the attached PMP is accessible.
 703 *
 704 *      LOCKING:
 705 *      Kernel thread context (may sleep).
 706 *
 707 *      RETURNS:
 708 *      0 on success, -errno otherwise.
 709 */
 710static int sata_pmp_revalidate_quick(struct ata_device *dev)
 711{
 712        unsigned int err_mask;
 713        u32 prod_id;
 714
 715        err_mask = sata_pmp_read(dev->link, SATA_PMP_GSCR_PROD_ID, &prod_id);
 716        if (err_mask) {
 717                ata_dev_err(dev,
 718                            "failed to read PMP product ID (Emask=0x%x)\n",
 719                            err_mask);
 720                return -EIO;
 721        }
 722
 723        if (prod_id != dev->gscr[SATA_PMP_GSCR_PROD_ID]) {
 724                ata_dev_err(dev, "PMP product ID mismatch\n");
 725                /* something weird is going on, request full PMP recovery */
 726                return -EIO;
 727        }
 728
 729        return 0;
 730}
 731
 732/**
 733 *      sata_pmp_eh_recover_pmp - recover PMP
 734 *      @ap: ATA port PMP is attached to
 735 *      @prereset: prereset method (can be NULL)
 736 *      @softreset: softreset method
 737 *      @hardreset: hardreset method
 738 *      @postreset: postreset method (can be NULL)
 739 *
 740 *      Recover PMP attached to @ap.  Recovery procedure is somewhat
 741 *      similar to that of ata_eh_recover() except that reset should
 742 *      always be performed in hard->soft sequence and recovery
 743 *      failure results in PMP detachment.
 744 *
 745 *      LOCKING:
 746 *      Kernel thread context (may sleep).
 747 *
 748 *      RETURNS:
 749 *      0 on success, -errno on failure.
 750 */
 751static int sata_pmp_eh_recover_pmp(struct ata_port *ap,
 752                ata_prereset_fn_t prereset, ata_reset_fn_t softreset,
 753                ata_reset_fn_t hardreset, ata_postreset_fn_t postreset)
 754{
 755        struct ata_link *link = &ap->link;
 756        struct ata_eh_context *ehc = &link->eh_context;
 757        struct ata_device *dev = link->device;
 758        int tries = ATA_EH_PMP_TRIES;
 759        int detach = 0, rc = 0;
 760        int reval_failed = 0;
 761
 762        DPRINTK("ENTER\n");
 763
 764        if (dev->flags & ATA_DFLAG_DETACH) {
 765                detach = 1;
 766                rc = -ENODEV;
 767                goto fail;
 768        }
 769
 770 retry:
 771        ehc->classes[0] = ATA_DEV_UNKNOWN;
 772
 773        if (ehc->i.action & ATA_EH_RESET) {
 774                struct ata_link *tlink;
 775
 776                /* reset */
 777                rc = ata_eh_reset(link, 0, prereset, softreset, hardreset,
 778                                  postreset);
 779                if (rc) {
 780                        ata_link_err(link, "failed to reset PMP, giving up\n");
 781                        goto fail;
 782                }
 783
 784                /* PMP is reset, SErrors cannot be trusted, scan all */
 785                ata_for_each_link(tlink, ap, EDGE) {
 786                        struct ata_eh_context *ehc = &tlink->eh_context;
 787
 788                        ehc->i.probe_mask |= ATA_ALL_DEVICES;
 789                        ehc->i.action |= ATA_EH_RESET;
 790                }
 791        }
 792
 793        /* If revalidation is requested, revalidate and reconfigure;
 794         * otherwise, do quick revalidation.
 795         */
 796        if (ehc->i.action & ATA_EH_REVALIDATE)
 797                rc = sata_pmp_revalidate(dev, ehc->classes[0]);
 798        else
 799                rc = sata_pmp_revalidate_quick(dev);
 800
 801        if (rc) {
 802                tries--;
 803
 804                if (rc == -ENODEV) {
 805                        ehc->i.probe_mask |= ATA_ALL_DEVICES;
 806                        detach = 1;
 807                        /* give it just two more chances */
 808                        tries = min(tries, 2);
 809                }
 810
 811                if (tries) {
 812                        /* consecutive revalidation failures? speed down */
 813                        if (reval_failed)
 814                                sata_down_spd_limit(link, 0);
 815                        else
 816                                reval_failed = 1;
 817
 818                        ehc->i.action |= ATA_EH_RESET;
 819                        goto retry;
 820                } else {
 821                        ata_dev_err(dev,
 822                                    "failed to recover PMP after %d tries, giving up\n",
 823                                    ATA_EH_PMP_TRIES);
 824                        goto fail;
 825                }
 826        }
 827
 828        /* okay, PMP resurrected */
 829        ehc->i.flags = 0;
 830
 831        DPRINTK("EXIT, rc=0\n");
 832        return 0;
 833
 834 fail:
 835        sata_pmp_detach(dev);
 836        if (detach)
 837                ata_eh_detach_dev(dev);
 838        else
 839                ata_dev_disable(dev);
 840
 841        DPRINTK("EXIT, rc=%d\n", rc);
 842        return rc;
 843}
 844
 845static int sata_pmp_eh_handle_disabled_links(struct ata_port *ap)
 846{
 847        struct ata_link *link;
 848        unsigned long flags;
 849        int rc;
 850
 851        spin_lock_irqsave(ap->lock, flags);
 852
 853        ata_for_each_link(link, ap, EDGE) {
 854                if (!(link->flags & ATA_LFLAG_DISABLED))
 855                        continue;
 856
 857                spin_unlock_irqrestore(ap->lock, flags);
 858
 859                /* Some PMPs require hardreset sequence to get
 860                 * SError.N working.
 861                 */
 862                sata_link_hardreset(link, sata_deb_timing_normal,
 863                                ata_deadline(jiffies, ATA_TMOUT_INTERNAL_QUICK),
 864                                NULL, NULL);
 865
 866                /* unconditionally clear SError.N */
 867                rc = sata_scr_write(link, SCR_ERROR, SERR_PHYRDY_CHG);
 868                if (rc) {
 869                        ata_link_err(link,
 870                                     "failed to clear SError.N (errno=%d)\n",
 871                                     rc);
 872                        return rc;
 873                }
 874
 875                spin_lock_irqsave(ap->lock, flags);
 876        }
 877
 878        spin_unlock_irqrestore(ap->lock, flags);
 879
 880        return 0;
 881}
 882
 883static int sata_pmp_handle_link_fail(struct ata_link *link, int *link_tries)
 884{
 885        struct ata_port *ap = link->ap;
 886        unsigned long flags;
 887
 888        if (link_tries[link->pmp] && --link_tries[link->pmp])
 889                return 1;
 890
 891        /* disable this link */
 892        if (!(link->flags & ATA_LFLAG_DISABLED)) {
 893                ata_link_warn(link,
 894                        "failed to recover link after %d tries, disabling\n",
 895                        ATA_EH_PMP_LINK_TRIES);
 896
 897                spin_lock_irqsave(ap->lock, flags);
 898                link->flags |= ATA_LFLAG_DISABLED;
 899                spin_unlock_irqrestore(ap->lock, flags);
 900        }
 901
 902        ata_dev_disable(link->device);
 903        link->eh_context.i.action = 0;
 904
 905        return 0;
 906}
 907
 908/**
 909 *      sata_pmp_eh_recover - recover PMP-enabled port
 910 *      @ap: ATA port to recover
 911 *
 912 *      Drive EH recovery operation for PMP enabled port @ap.  This
 913 *      function recovers host and PMP ports with proper retrials and
 914 *      fallbacks.  Actual recovery operations are performed using
 915 *      ata_eh_recover() and sata_pmp_eh_recover_pmp().
 916 *
 917 *      LOCKING:
 918 *      Kernel thread context (may sleep).
 919 *
 920 *      RETURNS:
 921 *      0 on success, -errno on failure.
 922 */
 923static int sata_pmp_eh_recover(struct ata_port *ap)
 924{
 925        struct ata_port_operations *ops = ap->ops;
 926        int pmp_tries, link_tries[SATA_PMP_MAX_PORTS];
 927        struct ata_link *pmp_link = &ap->link;
 928        struct ata_device *pmp_dev = pmp_link->device;
 929        struct ata_eh_context *pmp_ehc = &pmp_link->eh_context;
 930        u32 *gscr = pmp_dev->gscr;
 931        struct ata_link *link;
 932        struct ata_device *dev;
 933        unsigned int err_mask;
 934        u32 gscr_error, sntf;
 935        int cnt, rc;
 936
 937        pmp_tries = ATA_EH_PMP_TRIES;
 938        ata_for_each_link(link, ap, EDGE)
 939                link_tries[link->pmp] = ATA_EH_PMP_LINK_TRIES;
 940
 941 retry:
 942        /* PMP attached? */
 943        if (!sata_pmp_attached(ap)) {
 944                rc = ata_eh_recover(ap, ops->prereset, ops->softreset,
 945                                    ops->hardreset, ops->postreset, NULL);
 946                if (rc) {
 947                        ata_for_each_dev(dev, &ap->link, ALL)
 948                                ata_dev_disable(dev);
 949                        return rc;
 950                }
 951
 952                if (pmp_dev->class != ATA_DEV_PMP)
 953                        return 0;
 954
 955                /* new PMP online */
 956                ata_for_each_link(link, ap, EDGE)
 957                        link_tries[link->pmp] = ATA_EH_PMP_LINK_TRIES;
 958
 959                /* fall through */
 960        }
 961
 962        /* recover pmp */
 963        rc = sata_pmp_eh_recover_pmp(ap, ops->prereset, ops->softreset,
 964                                     ops->hardreset, ops->postreset);
 965        if (rc)
 966                goto pmp_fail;
 967
 968        /* PHY event notification can disturb reset and other recovery
 969         * operations.  Turn it off.
 970         */
 971        if (gscr[SATA_PMP_GSCR_FEAT_EN] & SATA_PMP_FEAT_NOTIFY) {
 972                gscr[SATA_PMP_GSCR_FEAT_EN] &= ~SATA_PMP_FEAT_NOTIFY;
 973
 974                err_mask = sata_pmp_write(pmp_link, SATA_PMP_GSCR_FEAT_EN,
 975                                          gscr[SATA_PMP_GSCR_FEAT_EN]);
 976                if (err_mask) {
 977                        ata_link_warn(pmp_link,
 978                                "failed to disable NOTIFY (err_mask=0x%x)\n",
 979                                err_mask);
 980                        goto pmp_fail;
 981                }
 982        }
 983
 984        /* handle disabled links */
 985        rc = sata_pmp_eh_handle_disabled_links(ap);
 986        if (rc)
 987                goto pmp_fail;
 988
 989        /* recover links */
 990        rc = ata_eh_recover(ap, ops->pmp_prereset, ops->pmp_softreset,
 991                            ops->pmp_hardreset, ops->pmp_postreset, &link);
 992        if (rc)
 993                goto link_fail;
 994
 995        /* clear SNotification */
 996        rc = sata_scr_read(&ap->link, SCR_NOTIFICATION, &sntf);
 997        if (rc == 0)
 998                sata_scr_write(&ap->link, SCR_NOTIFICATION, sntf);
 999
1000        /*
1001         * If LPM is active on any fan-out port, hotplug wouldn't
1002         * work.  Return w/ PHY event notification disabled.
1003         */
1004        ata_for_each_link(link, ap, EDGE)
1005                if (link->lpm_policy > ATA_LPM_MAX_POWER)
1006                        return 0;
1007
1008        /*
1009         * Connection status might have changed while resetting other
1010         * links, enable notification and check SATA_PMP_GSCR_ERROR
1011         * before returning.
1012         */
1013
1014        /* enable notification */
1015        if (pmp_dev->flags & ATA_DFLAG_AN) {
1016                gscr[SATA_PMP_GSCR_FEAT_EN] |= SATA_PMP_FEAT_NOTIFY;
1017
1018                err_mask = sata_pmp_write(pmp_link, SATA_PMP_GSCR_FEAT_EN,
1019                                          gscr[SATA_PMP_GSCR_FEAT_EN]);
1020                if (err_mask) {
1021                        ata_dev_err(pmp_dev,
1022                                    "failed to write PMP_FEAT_EN (Emask=0x%x)\n",
1023                                    err_mask);
1024                        rc = -EIO;
1025                        goto pmp_fail;
1026                }
1027        }
1028
1029        /* check GSCR_ERROR */
1030        err_mask = sata_pmp_read(pmp_link, SATA_PMP_GSCR_ERROR, &gscr_error);
1031        if (err_mask) {
1032                ata_dev_err(pmp_dev,
1033                            "failed to read PMP_GSCR_ERROR (Emask=0x%x)\n",
1034                            err_mask);
1035                rc = -EIO;
1036                goto pmp_fail;
1037        }
1038
1039        cnt = 0;
1040        ata_for_each_link(link, ap, EDGE) {
1041                if (!(gscr_error & (1 << link->pmp)))
1042                        continue;
1043
1044                if (sata_pmp_handle_link_fail(link, link_tries)) {
1045                        ata_ehi_hotplugged(&link->eh_context.i);
1046                        cnt++;
1047                } else {
1048                        ata_link_warn(link,
1049                                "PHY status changed but maxed out on retries, giving up\n");
1050                        ata_link_warn(link,
1051                                "Manually issue scan to resume this link\n");
1052                }
1053        }
1054
1055        if (cnt) {
1056                ata_port_info(ap,
1057                        "PMP SError.N set for some ports, repeating recovery\n");
1058                goto retry;
1059        }
1060
1061        return 0;
1062
1063 link_fail:
1064        if (sata_pmp_handle_link_fail(link, link_tries)) {
1065                pmp_ehc->i.action |= ATA_EH_RESET;
1066                goto retry;
1067        }
1068
1069        /* fall through */
1070 pmp_fail:
1071        /* Control always ends up here after detaching PMP.  Shut up
1072         * and return if we're unloading.
1073         */
1074        if (ap->pflags & ATA_PFLAG_UNLOADING)
1075                return rc;
1076
1077        if (!sata_pmp_attached(ap))
1078                goto retry;
1079
1080        if (--pmp_tries) {
1081                pmp_ehc->i.action |= ATA_EH_RESET;
1082                goto retry;
1083        }
1084
1085        ata_port_err(ap, "failed to recover PMP after %d tries, giving up\n",
1086                     ATA_EH_PMP_TRIES);
1087        sata_pmp_detach(pmp_dev);
1088        ata_dev_disable(pmp_dev);
1089
1090        return rc;
1091}
1092
1093/**
1094 *      sata_pmp_error_handler - do standard error handling for PMP-enabled host
1095 *      @ap: host port to handle error for
1096 *
1097 *      Perform standard error handling sequence for PMP-enabled host
1098 *      @ap.
1099 *
1100 *      LOCKING:
1101 *      Kernel thread context (may sleep).
1102 */
1103void sata_pmp_error_handler(struct ata_port *ap)
1104{
1105        ata_eh_autopsy(ap);
1106        ata_eh_report(ap);
1107        sata_pmp_eh_recover(ap);
1108        ata_eh_finish(ap);
1109}
1110
1111EXPORT_SYMBOL_GPL(sata_pmp_port_ops);
1112EXPORT_SYMBOL_GPL(sata_pmp_qc_defer_cmd_switch);
1113EXPORT_SYMBOL_GPL(sata_pmp_error_handler);
1114