adapters/pmcs/pmcs_ds.c

	pmcs_ds.c revision 145e0143b4896d03ce53b1af6787afa1a7e73959
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 *
 *
 * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * PM8001 device state recovery routines
 */

#include <sys/scsi/adapters/pmcs/pmcs.h>

/*
 * SAS Topology Configuration
 */
static void pmcs_handle_ds_recovery_error(pmcs_phy_t *phyp,
    pmcs_xscsi_t *tgt, pmcs_hw_t *pwp, const char *func_name, int line,
    char *reason_string);

/*
 * Get device state.  Called with statlock and PHY lock held.
 */
static int
pmcs_get_dev_state(pmcs_hw_t *pwp, pmcs_phy_t *phyp, pmcs_xscsi_t *xp,
    uint8_t *ds)
{
    uint32_t htag, *ptr, msg[PMCS_MSG_SIZE];
    int result;
    struct pmcwork *pwrk;

    pmcs_prt(pwp, PMCS_PRT_DEBUG3, phyp, xp, "%s: tgt(0x%p)", __func__,
        (void *)xp);

    if (xp != NULL) {
        ASSERT(mutex_owned(&xp->statlock));
    }
    ASSERT(mutex_owned(&phyp->phy_lock));

    pwrk = pmcs_gwork(pwp, PMCS_TAG_TYPE_WAIT, phyp);
    if (pwrk == NULL) {
        pmcs_prt(pwp, PMCS_PRT_ERR, phyp, xp, pmcs_nowrk, __func__);
        return (-1);
    }
    pwrk->arg = msg;
    pwrk->dtype = phyp->dtype;

    if (phyp->valid_device_id == 0) {
        pmcs_pwork(pwp, pwrk);
        pmcs_prt(pwp, PMCS_PRT_DEBUG, phyp, xp,
            "%s: Invalid DeviceID", __func__);
        return (-1);
    }
    htag = pwrk->htag;
    msg[0] = LE_32(PMCS_HIPRI(pwp, PMCS_OQ_GENERAL,
        PMCIN_GET_DEVICE_STATE));
    msg[1] = LE_32(pwrk->htag);
    msg[2] = LE_32(phyp->device_id);

    mutex_enter(&pwp->iqp_lock[PMCS_IQ_OTHER]);
    ptr = GET_IQ_ENTRY(pwp, PMCS_IQ_OTHER);
    if (ptr == NULL) {
        mutex_exit(&pwp->iqp_lock[PMCS_IQ_OTHER]);
        pmcs_pwork(pwp, pwrk);
        pmcs_prt(pwp, PMCS_PRT_ERR, phyp, xp, pmcs_nomsg, __func__);
        return (-1);
    }
    COPY_MESSAGE(ptr, msg, PMCS_MSG_SIZE);
    pwrk->state = PMCS_WORK_STATE_ONCHIP;
    INC_IQ_ENTRY(pwp, PMCS_IQ_OTHER);

    if (xp != NULL) {
        mutex_exit(&xp->statlock);
    }
    pmcs_unlock_phy(phyp);
    WAIT_FOR(pwrk, 1000, result);
    pmcs_lock_phy(phyp);
    pmcs_pwork(pwp, pwrk);

    if (xp != NULL) {
        mutex_enter(&xp->statlock);
    }

    if (result) {
        pmcs_timed_out(pwp, htag, __func__);
        pmcs_prt(pwp, PMCS_PRT_DEBUG, phyp, xp,
            "%s: cmd timed out, returning", __func__);
        return (-1);
    }
    if (LE_32(msg[2]) == 0) {
        *ds = (uint8_t)(LE_32(msg[4]));
        if (xp == NULL) {
            pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, phyp, xp,
                "%s: retrieved_ds=0x%x", __func__, *ds);
        } else if (*ds !=  xp->dev_state) {
            pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, phyp, xp,
                "%s: retrieved_ds=0x%x, target_ds=0x%x", __func__,
                *ds, xp->dev_state);
        }
        return (0);
    } else {
        pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, phyp, xp,
            "%s: cmd failed Status(0x%x), returning ", __func__,
            LE_32(msg[2]));
        return (-1);
    }
}

/*
 * Set device state.  Called with target's statlock and PHY lock held.
 */
static int
pmcs_set_dev_state(pmcs_hw_t *pwp, pmcs_phy_t *phyp, pmcs_xscsi_t *xp,
    uint8_t ds)
{
    uint32_t htag, *ptr, msg[PMCS_MSG_SIZE];
    int result;
    uint8_t pds, nds;
    struct pmcwork *pwrk;

    pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, phyp, xp,
        "%s: ds: 0x%x tgt: 0x%p phy: 0x%p", __func__, ds, (void *)xp,
        (void *)phyp);

    if (phyp == NULL) {
        pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, NULL, xp,
            "%s: PHY is NULL", __func__);
        return (-1);
    }

    pwrk = pmcs_gwork(pwp, PMCS_TAG_TYPE_WAIT, phyp);
    if (pwrk == NULL) {
        pmcs_prt(pwp, PMCS_PRT_ERR, phyp, xp, pmcs_nowrk, __func__);
        return (-1);
    }
    if (phyp->valid_device_id == 0) {
        pmcs_pwork(pwp, pwrk);
        pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, phyp, xp,
            "%s: Invalid DeviceID", __func__);
        return (-1);
    }
    pwrk->arg = msg;
    pwrk->dtype = phyp->dtype;
    htag = pwrk->htag;
    msg[0] = LE_32(PMCS_HIPRI(pwp, PMCS_OQ_GENERAL,
        PMCIN_SET_DEVICE_STATE));
    msg[1] = LE_32(pwrk->htag);
    msg[2] = LE_32(phyp->device_id);
    msg[3] = LE_32(ds);

    mutex_enter(&pwp->iqp_lock[PMCS_IQ_OTHER]);
    ptr = GET_IQ_ENTRY(pwp, PMCS_IQ_OTHER);
    if (ptr == NULL) {
        mutex_exit(&pwp->iqp_lock[PMCS_IQ_OTHER]);
        pmcs_pwork(pwp, pwrk);
        pmcs_prt(pwp, PMCS_PRT_ERR, phyp, xp, pmcs_nomsg, __func__);
        return (-1);
    }
    COPY_MESSAGE(ptr, msg, PMCS_MSG_SIZE);
    pwrk->state = PMCS_WORK_STATE_ONCHIP;
    INC_IQ_ENTRY(pwp, PMCS_IQ_OTHER);

    if (xp != NULL) {
        mutex_exit(&xp->statlock);
    }
    pmcs_unlock_phy(phyp);
    WAIT_FOR(pwrk, 1000, result);
    pmcs_lock_phy(phyp);
    pmcs_pwork(pwp, pwrk);
    if (xp != NULL) {
        mutex_enter(&xp->statlock);
    }

    if (result) {
        pmcs_timed_out(pwp, htag, __func__);
        pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, phyp, xp,
            "%s: cmd timed out, returning", __func__);
        return (-1);
    }
    if (LE_32(msg[2]) == 0) {
        pds = (uint8_t)(LE_32(msg[4]) >> 4);
        nds = (uint8_t)(LE_32(msg[4]) & 0x0000000f);
        pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, phyp, xp,
            "%s: previous_ds=0x%x, new_ds=0x%x", __func__, pds, nds);
        if (xp != NULL) {
            xp->dev_state = nds;
        }
        return (0);
    } else {
        pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, phyp, xp,
            "%s: cmd failed Status(0x%x), returning ", __func__,
            LE_32(msg[2]));
        return (-1);
    }
}

void
pmcs_dev_state_recovery(pmcs_hw_t *pwp, pmcs_phy_t *phyp)
{
    uint8_t ds, tgt_dev_state;
    int rc;
    pmcs_xscsi_t *tgt;
    pmcs_phy_t *pptr, *pnext, *pchild;

    /*
     * First time, check to see if we're already performing recovery
     */
    if (phyp == NULL) {
        mutex_enter(&pwp->lock);
        if (pwp->ds_err_recovering) {
            mutex_exit(&pwp->lock);
            SCHEDULE_WORK(pwp, PMCS_WORK_DS_ERR_RECOVERY);
            return;
        }

        pwp->ds_err_recovering = 1;
        pptr = pwp->root_phys;
        mutex_exit(&pwp->lock);
    } else {
        pptr = phyp;
    }

    while (pptr) {
        /*
         * Since ds_err_recovering is set, we can be assured these
         * PHYs won't disappear on us while we do this.
         */
        pmcs_lock_phy(pptr);
        pchild = pptr->children;
        pnext = pptr->sibling;
        pmcs_unlock_phy(pptr);

        if (pchild) {
            pmcs_dev_state_recovery(pwp, pchild);
        }

        tgt = NULL;
        pmcs_lock_phy(pptr);

        if (pptr->dead) {
            goto next_phy;
        }

        tgt = pptr->target;

        if (tgt != NULL) {
            mutex_enter(&tgt->statlock);
            if (tgt->recover_wait == 0) {
                goto next_phy;
            }
            tgt_dev_state = tgt->dev_state;
        } else {
            tgt_dev_state = PMCS_DEVICE_STATE_NOT_AVAILABLE;
        }

        if (pptr->prev_recovery) {
            if (ddi_get_lbolt() - pptr->prev_recovery <
                drv_usectohz(PMCS_DS_RECOVERY_INTERVAL)) {
                pmcs_prt(pwp, PMCS_PRT_DEBUG2, pptr, tgt,
                    "%s: DS recovery on PHY %s "
                    "re-invoked too soon. Skipping...",
                    __func__, pptr->path);
                goto next_phy;
            }
        }
        pptr->prev_recovery = ddi_get_lbolt();

        /*
         * Step 1: Put the device into the IN_RECOVERY state
         */
        rc = pmcs_get_dev_state(pwp, pptr, tgt, &ds);
        if (rc != 0) {
            pmcs_prt(pwp, PMCS_PRT_DEBUG, pptr, tgt,
                "%s: pmcs_get_dev_state on PHY %s "
                "failed (rc=%d)",
                __func__, pptr->path, rc);

            pmcs_handle_ds_recovery_error(pptr, tgt, pwp,
                __func__, __LINE__, "pmcs_get_dev_state");

            goto next_phy;
        }

        if ((tgt_dev_state == ds) &&
            (ds == PMCS_DEVICE_STATE_IN_RECOVERY)) {
            pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, pptr, tgt,
                "%s: Target 0x%p already IN_RECOVERY", __func__,
                (void *)tgt);
        } else {
            if (tgt != NULL) {
                tgt->dev_state = ds;
            }
            tgt_dev_state = ds;
            ds = PMCS_DEVICE_STATE_IN_RECOVERY;
            rc = pmcs_send_err_recovery_cmd(pwp, ds, pptr, tgt);
            pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, pptr, tgt,
                "%s: pmcs_send_err_recovery_cmd "
                "result(%d) tgt(0x%p) ds(0x%x) tgt->ds(0x%x)",
                __func__, rc, (void *)tgt, ds, tgt_dev_state);

            if (rc) {
                pmcs_prt(pwp, PMCS_PRT_DEBUG, pptr, tgt,
                    "%s: pmcs_send_err_recovery_cmd to PHY %s "
                    "failed (rc=%d)",
                    __func__, pptr->path, rc);

                pmcs_handle_ds_recovery_error(pptr, tgt, pwp,
                    __func__, __LINE__,
                    "pmcs_send_err_recovery_cmd");

                goto next_phy;
            }
        }

        /*
         * Step 2: Perform a hard reset on the PHY
         */
        pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, pptr, tgt,
            "%s: Issue HARD_RESET to PHY %s", __func__, pptr->path);
        /*
         * Must release statlock here because pmcs_reset_phy will
         * drop and reacquire the PHY lock.
         */
        if (tgt != NULL) {
            mutex_exit(&tgt->statlock);
        }
        rc = pmcs_reset_phy(pwp, pptr, PMCS_PHYOP_HARD_RESET);
        if (tgt != NULL) {
            mutex_enter(&tgt->statlock);
        }
        if (rc) {
            pmcs_prt(pwp, PMCS_PRT_DEBUG, pptr, tgt,
                "%s: HARD_RESET to PHY %s failed (rc=%d)",
                __func__, pptr->path, rc);

            pmcs_handle_ds_recovery_error(pptr, tgt, pwp,
                __func__, __LINE__, "HARD_RESET");

            goto next_phy;
        }

        /*
         * Step 3: Abort all I/Os to the device
         */
        if (pptr->abort_all_start) {
            while (pptr->abort_all_start) {
                pmcs_prt(pwp, PMCS_PRT_DEBUG, pptr, tgt,
                    "%s: Waiting for outstanding ABORT_ALL on "
                    "PHY 0x%p", __func__, (void *)pptr);
                cv_wait(&pptr->abort_all_cv, &pptr->phy_lock);
            }
        } else {
            if (tgt != NULL) {
                mutex_exit(&tgt->statlock);
            }
            rc = pmcs_abort(pwp, pptr, pptr->device_id, 1, 1);
            if (tgt != NULL) {
                mutex_enter(&tgt->statlock);
            }
            if (rc != 0) {
                pptr->abort_pending = 1;
                pmcs_prt(pwp, PMCS_PRT_DEBUG, pptr, tgt,
                    "%s: pmcs_abort to PHY %s failed (rc=%d)",
                    __func__, pptr->path, rc);

                pmcs_handle_ds_recovery_error(pptr, tgt,
                    pwp, __func__, __LINE__, "pmcs_abort");

                goto next_phy;
            }
        }

        /*
         * Step 4: Set the device back to OPERATIONAL state
         */
        pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, pptr, tgt,
            "%s: Set PHY/tgt 0x%p/0x%p to OPERATIONAL state",
            __func__, (void *)pptr, (void *)tgt);
        rc = pmcs_set_dev_state(pwp, pptr, tgt,
            PMCS_DEVICE_STATE_OPERATIONAL);
        if (rc == 0) {
            if (tgt != NULL) {
                tgt->recover_wait = 0;
            }
            pptr->ds_recovery_retries = 0;

            if ((pptr->ds_prev_good_recoveries == 0) ||
                (ddi_get_lbolt() - pptr->last_good_recovery >
                drv_usectohz(PMCS_MAX_DS_RECOVERY_TIME))) {
                pptr->last_good_recovery = ddi_get_lbolt();
                pptr->ds_prev_good_recoveries = 1;
            } else if (ddi_get_lbolt() < pptr->last_good_recovery +
                drv_usectohz(PMCS_MAX_DS_RECOVERY_TIME)) {
                pptr->ds_prev_good_recoveries++;
            } else {
                pmcs_handle_ds_recovery_error(pptr, tgt, pwp,
                    __func__, __LINE__, "Max recovery"
                    "attempts reached. Declaring PHY dead");
            }

            /*
             * Don't bother to run the work queues if the PHY
             * is dead.
             */
            if (tgt && tgt->phy && !tgt->phy->dead) {
                SCHEDULE_WORK(pwp, PMCS_WORK_RUN_QUEUES);
                (void) ddi_taskq_dispatch(pwp->tq, pmcs_worker,
                    pwp, DDI_NOSLEEP);
            }
        } else {
            pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, pptr, tgt,
                "%s: Failed to SET tgt 0x%p to OPERATIONAL state",
                __func__, (void *)tgt);

            pmcs_handle_ds_recovery_error(pptr, tgt, pwp,
                __func__, __LINE__, "SET tgt to OPERATIONAL state");

            goto next_phy;
        }

next_phy:
        if (tgt) {
            mutex_exit(&tgt->statlock);
        }
        pmcs_unlock_phy(pptr);
        pptr = pnext;
    }

    /*
     * Only clear ds_err_recovering if we're exiting for good and not
     * just unwinding from recursion
     */
    if (phyp == NULL) {
        mutex_enter(&pwp->lock);
        pwp->ds_err_recovering = 0;
        mutex_exit(&pwp->lock);
    }
}

/*
 * Called with target's statlock held (if target is non-NULL) and PHY lock held.
 */
int
pmcs_send_err_recovery_cmd(pmcs_hw_t *pwp, uint8_t dev_state, pmcs_phy_t *phyp,
    pmcs_xscsi_t *tgt)
{
    int rc = -1;
    uint8_t tgt_dev_state = PMCS_DEVICE_STATE_NOT_AVAILABLE;

    if (tgt != NULL) {
        ASSERT(mutex_owned(&tgt->statlock));
        if (tgt->recovering) {
            return (0);
        }

        tgt->recovering = 1;
        tgt_dev_state = tgt->dev_state;
    }

    if (phyp == NULL) {
        pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, NULL, tgt,
            "%s: PHY is NULL", __func__);
        return (-1);
    }

    ASSERT(mutex_owned(&phyp->phy_lock));

    pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, phyp, tgt,
        "%s: ds: 0x%x, tgt ds(0x%x)", __func__, dev_state, tgt_dev_state);

    switch (dev_state) {
    case PMCS_DEVICE_STATE_IN_RECOVERY:
        if (tgt_dev_state == PMCS_DEVICE_STATE_IN_RECOVERY) {
            pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, phyp, tgt,
                "%s: Target 0x%p already IN_RECOVERY", __func__,
                (void *)tgt);
            rc = 0; /* This is not an error */
            goto no_action;
        }

        rc = pmcs_set_dev_state(pwp, phyp, tgt,
            PMCS_DEVICE_STATE_IN_RECOVERY);
        if (rc != 0) {
            pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, phyp, tgt,
                "%s(1): Failed to set tgt(0x%p) to IN_RECOVERY",
                __func__, (void *)tgt);
        }

        break;

    case PMCS_DEVICE_STATE_OPERATIONAL:
        if (tgt_dev_state != PMCS_DEVICE_STATE_IN_RECOVERY) {
            pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, phyp, tgt,
                "%s: Target 0x%p not ready to go OPERATIONAL",
                __func__, (void *)tgt);
            goto no_action;
        }

        rc = pmcs_set_dev_state(pwp, phyp, tgt,
            PMCS_DEVICE_STATE_OPERATIONAL);
        if (tgt != NULL) {
            tgt->reset_success = 1;
        }
        if (rc != 0) {
            pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, phyp, tgt,
                "%s(2): Failed to SET tgt(0x%p) to OPERATIONAL",
                __func__, (void *)tgt);
            if (tgt != NULL) {
                tgt->reset_success = 0;
            }
        }

        break;

    case PMCS_DEVICE_STATE_NON_OPERATIONAL:
        PHY_CHANGED(pwp, phyp);
        RESTART_DISCOVERY(pwp);
        pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, phyp, tgt,
            "%s: Device at %s is non-operational",
            __func__, phyp->path);
        if (tgt != NULL) {
            tgt->dev_state = PMCS_DEVICE_STATE_NON_OPERATIONAL;
        }
        rc = 0;

        break;

    default:
        pmcs_prt(pwp, PMCS_PRT_DEBUG_DEV_STATE, phyp, tgt,
            "%s: Invalid state requested (%d)", __func__,
            dev_state);
        break;

    }

no_action:
    if (tgt != NULL) {
        tgt->recovering = 0;
    }
    return (rc);
}

/*
 * Start ssp event recovery. We have to schedule recovery operation because
 * it involves sending multiple commands to device and we should not do it
 * in the interrupt context.
 * If it is failure of a recovery command, let the recovery thread deal with it.
 * Called with pmcwork lock held.
 */

void
pmcs_start_ssp_event_recovery(pmcs_hw_t *pwp, pmcwork_t *pwrk, uint32_t *iomb,
    size_t amt)
{
    pmcs_xscsi_t *tgt = pwrk->xp;
    uint32_t event = LE_32(iomb[2]);
    pmcs_phy_t *pptr = pwrk->phy;
    uint32_t tag;

    if (tgt != NULL) {
        mutex_enter(&tgt->statlock);
        if (!tgt->assigned) {
            if (pptr) {
                pmcs_dec_phy_ref_count(pptr);
            }
            pptr = NULL;
            pwrk->phy = NULL;
        }
        mutex_exit(&tgt->statlock);
    }
    if (pptr == NULL) {
        /*
         * No target, need to run RE-DISCOVERY here.
         */
        if (pwrk->state != PMCS_WORK_STATE_TIMED_OUT) {
            pwrk->state = PMCS_WORK_STATE_INTR;
        }
        /*
         * Although we cannot mark phy to force abort nor mark phy
         * as changed, killing of a target would take care of aborting
         * commands for the device.
         */
        pmcs_prt(pwp, PMCS_PRT_DEBUG, pptr, tgt,
            "%s: No valid target for event processing. Reconfigure.",
            __func__);
        pmcs_pwork(pwp, pwrk);
        RESTART_DISCOVERY(pwp);
        return;
    } else {
        pmcs_lock_phy(pptr);
        mutex_enter(&tgt->statlock);
        if (event == PMCOUT_STATUS_OPEN_CNX_ERROR_IT_NEXUS_LOSS) {
            if (tgt->dev_state !=
                PMCS_DEVICE_STATE_NON_OPERATIONAL) {
                pmcs_prt(pwp, PMCS_PRT_DEBUG, pptr, tgt,
                    "%s: Device at %s is non-operational",
                    __func__, pptr->path);
                tgt->dev_state =
                    PMCS_DEVICE_STATE_NON_OPERATIONAL;
            }
            pptr->abort_pending = 1;
            mutex_exit(&tgt->statlock);
            pmcs_unlock_phy(pptr);
            mutex_exit(&pwrk->lock);
            SCHEDULE_WORK(pwp, PMCS_WORK_ABORT_HANDLE);
            RESTART_DISCOVERY(pwp);
            return;
        }

        /*
         * If this command is run in WAIT mode, it is a failing recovery
         * command. If so, just wake up recovery thread waiting for
         * command completion.
         */
        tag = PMCS_TAG_TYPE(pwrk->htag);
        if (tag == PMCS_TAG_TYPE_WAIT) {
            pwrk->htag |= PMCS_TAG_DONE;
            if (pwrk->arg && amt) {
                (void) memcpy(pwrk->arg, iomb, amt);
            }
            cv_signal(&pwrk->sleep_cv);
            mutex_exit(&tgt->statlock);
            pmcs_unlock_phy(pptr);
            mutex_exit(&pwrk->lock);
            return;
        }

        /*
         * To recover from primary failures,
         * we need to schedule handling events recovery.
         */
        tgt->event_recovery = 1;
        mutex_exit(&tgt->statlock);
        pmcs_unlock_phy(pptr);
        pwrk->ssp_event = event;
        pmcs_prt(pwp, PMCS_PRT_DEBUG, pptr, tgt,
            "%s: Scheduling SSP event recovery for tgt(0x%p) "
            "pwrk(%p) tag(0x%x)", __func__, (void *)tgt, (void *)pwrk,
            pwrk->htag);
        mutex_exit(&pwrk->lock);
        SCHEDULE_WORK(pwp, PMCS_WORK_SSP_EVT_RECOVERY);
    }

    /* Work cannot be completed until event recovery is completed. */
}

/*
 * SSP target event recovery
 * Entered with a phy lock held
 * Pwrk lock is not needed - pwrk is on the target aq and no other thread
 * will do anything with it until this thread starts the chain of recovery.
 * Statlock may be acquired and released.
 */

void
pmcs_tgt_event_recovery(pmcs_hw_t *pwp, pmcwork_t *pwrk)
{
    pmcs_phy_t *pptr = pwrk->phy;
    pmcs_cmd_t *sp = pwrk->arg;
    pmcs_lun_t *lun = sp->cmd_lun;
    pmcs_xscsi_t *tgt = pwrk->xp;
    uint32_t event;
    uint32_t htag;
    uint32_t status;
    uint8_t dstate;
    int rv;

    ASSERT(pwrk->arg != NULL);
    ASSERT(pwrk->xp != NULL);
    pmcs_prt(pwp, PMCS_PRT_DEBUG, pptr, tgt,
        "%s: event recovery for target 0x%p", __func__, (void *)pwrk->xp);
    htag = pwrk->htag;
    event = pwrk->ssp_event;
    pwrk->ssp_event = 0xffffffff;
    if (event == PMCOUT_STATUS_XFER_ERR_BREAK ||
        event == PMCOUT_STATUS_XFER_ERR_PHY_NOT_READY ||
        event == PMCOUT_STATUS_XFER_ERROR_CMD_ISSUE_ACK_NAK_TIMEOUT) {
        /* Command may be still pending on device */
        rv = pmcs_ssp_tmf(pwp, pptr, SAS_QUERY_TASK, htag,
            lun->lun_num, &status);
        if (rv != 0) {
            goto out;
        }
        if (status == SAS_RSP_TMF_COMPLETE) {
            /* Command NOT pending on a device */
            pmcs_prt(pwp, PMCS_PRT_DEBUG, pptr, tgt,
                "%s: No pending command for tgt 0x%p",
                __func__, (void *)tgt);
            /* Nothing more to do, just abort it on chip */
            htag = 0;
        }
    }
    /*
     * All other events left the command pending in the host
     * Send abort task and abort it on the chip
     */
    if (htag != 0) {
        if (pmcs_ssp_tmf(pwp, pptr, SAS_ABORT_TASK, htag,
            lun->lun_num, &status))
            goto out;
    }
    (void) pmcs_abort(pwp, pptr, pwrk->htag, 0, 1);
    /*
     * Abort either took care of work completion, or put device in
     * a recovery state
     */
    return;
out:
    /* Abort failed, do full device recovery */
    mutex_enter(&tgt->statlock);
    if (!pmcs_get_dev_state(pwp, pptr, tgt, &dstate))
        tgt->dev_state = dstate;

    if ((tgt->dev_state != PMCS_DEVICE_STATE_IN_RECOVERY) &&
        (tgt->dev_state != PMCS_DEVICE_STATE_NON_OPERATIONAL)) {
        pmcs_prt(pwp, PMCS_PRT_DEBUG, pptr, tgt,
            "%s: Setting IN_RECOVERY for tgt 0x%p",
            __func__, (void *)tgt);
        (void) pmcs_send_err_recovery_cmd(pwp,
            PMCS_DEVICE_STATE_IN_RECOVERY, pptr, tgt);
    }
    mutex_exit(&tgt->statlock);
}

/*
 * SSP event recovery task.
 */
void
pmcs_ssp_event_recovery(pmcs_hw_t *pwp)
{
    int idx;
    pmcs_xscsi_t *tgt;
    pmcs_cmd_t *cp;
    pmcwork_t *pwrk;
    pmcs_phy_t *pphy;
    int er_flag;
    uint32_t idxpwrk;

restart:
    for (idx = 0; idx < pwp->max_dev; idx++) {
        mutex_enter(&pwp->lock);
        tgt = pwp->targets[idx];
        mutex_exit(&pwp->lock);
        if (tgt != NULL) {
            mutex_enter(&tgt->statlock);
            if (!tgt->assigned) {
                mutex_exit(&tgt->statlock);
                continue;
            }
            pphy = tgt->phy;
            er_flag = tgt->event_recovery;
            mutex_exit(&tgt->statlock);
            if (pphy != NULL && er_flag != 0) {
                pmcs_lock_phy(pphy);
                mutex_enter(&tgt->statlock);
                pmcs_prt(pwp, PMCS_PRT_DEBUG, pphy, tgt,
                    "%s: found target(0x%p)", __func__,
                    (void *) tgt);

                /* Check what cmd expects recovery */
                mutex_enter(&tgt->aqlock);
                STAILQ_FOREACH(cp, &tgt->aq, cmd_next) {
                    /*
                     * Since work structure is on this
                     * target aq, and only this thread
                     * is accessing it now, we do not need
                     * to lock it
                     */
                    idxpwrk = PMCS_TAG_INDEX(cp->cmd_tag);
                    pwrk = &pwp->work[idxpwrk];
                    if (pwrk->htag != cp->cmd_tag) {
                        /*
                         * aq may contain TMF commands,
                         * so we may not find work
                         * structure with htag
                         */
                        break;
                    }
                    if (pwrk->ssp_event != 0 &&
                        pwrk->ssp_event !=
                        PMCS_REC_EVENT) {
                        pmcs_prt(pwp,
                            PMCS_PRT_DEBUG, pphy, tgt,
                            "%s: pwrk(%p) ctag(0x%x)",
                            __func__, (void *) pwrk,
                            cp->cmd_tag);
                        mutex_exit(&tgt->aqlock);
                        mutex_exit(&tgt->statlock);
                        pmcs_tgt_event_recovery(
                            pwp, pwrk);
                        /*
                         * We dropped statlock, so
                         * restart scanning from scratch
                         */
                        pmcs_unlock_phy(pphy);
                        goto restart;
                    }
                }
                mutex_exit(&tgt->aqlock);
                tgt->event_recovery = 0;
                pmcs_prt(pwp, PMCS_PRT_DEBUG, pphy, tgt,
                    "%s: end of SSP event recovery for "
                    "target(0x%p)", __func__, (void *) tgt);
                mutex_exit(&tgt->statlock);
                pmcs_unlock_phy(pphy);
            }
        }
    }
    pmcs_prt(pwp, PMCS_PRT_DEBUG, NULL, NULL,
        "%s: end of SSP event recovery for pwp(0x%p)", __func__,
        (void *) pwp);
}

void
pmcs_start_dev_state_recovery(pmcs_xscsi_t *xp, pmcs_phy_t *phyp)
{
    ASSERT(mutex_owned(&xp->statlock));
    ASSERT(xp->pwp != NULL);

    if (xp->recover_wait == 0) {
        pmcs_prt(xp->pwp, PMCS_PRT_DEBUG_DEV_STATE, phyp, xp,
            "%s: Start ds_recovery for tgt 0x%p/PHY 0x%p (%s)",
            __func__, (void *)xp, (void *)phyp, phyp->path);
        xp->recover_wait = 1;

        /*
         * Rather than waiting for the watchdog timer, we'll
         * kick it right now.
         */
        SCHEDULE_WORK(xp->pwp, PMCS_WORK_DS_ERR_RECOVERY);
        (void) ddi_taskq_dispatch(xp->pwp->tq, pmcs_worker, xp->pwp,
            DDI_NOSLEEP);
    }
}

/*
 * Increment the phy ds error retry count.
 * If too many retries, mark phy dead and restart discovery;
 * otherwise schedule ds recovery.
 */
static void
pmcs_handle_ds_recovery_error(pmcs_phy_t *phyp, pmcs_xscsi_t *tgt,
    pmcs_hw_t *pwp, const char *func_name, int line, char *reason_string)
{
    ASSERT(mutex_owned(&phyp->phy_lock));
    ASSERT((tgt == NULL) || mutex_owned(&tgt->statlock));

    phyp->ds_recovery_retries++;

    if (phyp->ds_recovery_retries > PMCS_MAX_DS_RECOVERY_RETRIES) {
        pmcs_prt(pwp, PMCS_PRT_DEBUG, phyp, tgt,
            "%s: retry limit reached after %s to PHY %s failed",
            func_name, reason_string, phyp->path);
        if (tgt != NULL) {
            tgt->recover_wait = 0;
        }
        phyp->dead = 1;
        PHY_CHANGED_AT_LOCATION(pwp, phyp, func_name, line);
        RESTART_DISCOVERY(pwp);
    } else if ((phyp->ds_prev_good_recoveries >
        PMCS_MAX_DS_RECOVERY_RETRIES) &&
        (phyp->last_good_recovery + drv_usectohz(PMCS_MAX_DS_RECOVERY_TIME)
        < ddi_get_lbolt())) {
        pmcs_prt(pwp, PMCS_PRT_DEBUG, phyp, tgt, "%s: max number of "
            "successful recoveries reached, declaring PHY %s dead",
            __func__, phyp->path);
        if (tgt != NULL) {
            tgt->recover_wait = 0;
        }
        phyp->dead = 1;
        PHY_CHANGED_AT_LOCATION(pwp, phyp, func_name, line);
        RESTART_DISCOVERY(pwp);
    } else {
        SCHEDULE_WORK(pwp, PMCS_WORK_DS_ERR_RECOVERY);
    }
}