xref: /kernel/linux/linux-5.10/drivers/scsi/esas2r/esas2r_int.c (revision 8c2ecf20)

/*
 *  linux/drivers/scsi/esas2r/esas2r_int.c
 *      esas2r interrupt handling
 *
 *  Copyright (c) 2001-2013 ATTO Technology, Inc.
 *  (mailto:linuxdrivers@attotech.com)
 */
/*=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=*/
/*
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; version 2 of the License.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  NO WARRANTY
 *  THE PROGRAM IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OR
 *  CONDITIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED INCLUDING, WITHOUT
 *  LIMITATION, ANY WARRANTIES OR CONDITIONS OF TITLE, NON-INFRINGEMENT,
 *  MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. Each Recipient is
 *  solely responsible for determining the appropriateness of using and
 *  distributing the Program and assumes all risks associated with its
 *  exercise of rights under this Agreement, including but not limited to
 *  the risks and costs of program errors, damage to or loss of data,
 *  programs or equipment, and unavailability or interruption of operations.
 *
 *  DISCLAIMER OF LIABILITY
 *  NEITHER RECIPIENT NOR ANY CONTRIBUTORS SHALL HAVE ANY LIABILITY FOR ANY
 *  DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 *  DAMAGES (INCLUDING WITHOUT LIMITATION LOST PROFITS), HOWEVER CAUSED AND
 *  ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
 *  TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
 *  USE OR DISTRIBUTION OF THE PROGRAM OR THE EXERCISE OF ANY RIGHTS GRANTED
 *  HEREUNDER, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGES
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
/*=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=*/

#include "esas2r.h"

/* Local function prototypes */
static void esas2r_doorbell_interrupt(struct esas2r_adapter *a, u32 doorbell);
static void esas2r_get_outbound_responses(struct esas2r_adapter *a);
static void esas2r_process_bus_reset(struct esas2r_adapter *a);

/*
 * Poll the adapter for interrupts and service them.
 * This function handles both legacy interrupts and MSI.
 */
void esas2r_polled_interrupt(struct esas2r_adapter *a)
{
	u32 intstat;
	u32 doorbell;

	esas2r_disable_chip_interrupts(a);

	intstat = esas2r_read_register_dword(a, MU_INT_STATUS_OUT);

	if (intstat & MU_INTSTAT_POST_OUT) {
		/* clear the interrupt */

		esas2r_write_register_dword(a, MU_OUT_LIST_INT_STAT,
					    MU_OLIS_INT);
		esas2r_flush_register_dword(a, MU_OUT_LIST_INT_STAT);

		esas2r_get_outbound_responses(a);
	}

	if (intstat & MU_INTSTAT_DRBL) {
		doorbell = esas2r_read_register_dword(a, MU_DOORBELL_OUT);
		if (doorbell != 0)
			esas2r_doorbell_interrupt(a, doorbell);
	}

	esas2r_enable_chip_interrupts(a);

	if (atomic_read(&a->disable_cnt) == 0)
		esas2r_do_deferred_processes(a);
}

/*
 * Legacy and MSI interrupt handlers.  Note that the legacy interrupt handler
 * schedules a TASKLET to process events, whereas the MSI handler just
 * processes interrupt events directly.
 */
irqreturn_t esas2r_interrupt(int irq, void *dev_id)
{
	struct esas2r_adapter *a = (struct esas2r_adapter *)dev_id;

	if (!esas2r_adapter_interrupt_pending(a))
		return IRQ_NONE;

	set_bit(AF2_INT_PENDING, &a->flags2);
	esas2r_schedule_tasklet(a);

	return IRQ_HANDLED;
}

void esas2r_adapter_interrupt(struct esas2r_adapter *a)
{
	u32 doorbell;

	if (likely(a->int_stat & MU_INTSTAT_POST_OUT)) {
		/* clear the interrupt */
		esas2r_write_register_dword(a, MU_OUT_LIST_INT_STAT,
					    MU_OLIS_INT);
		esas2r_flush_register_dword(a, MU_OUT_LIST_INT_STAT);
		esas2r_get_outbound_responses(a);
	}

	if (unlikely(a->int_stat & MU_INTSTAT_DRBL)) {
		doorbell = esas2r_read_register_dword(a, MU_DOORBELL_OUT);
		if (doorbell != 0)
			esas2r_doorbell_interrupt(a, doorbell);
	}

	a->int_mask = ESAS2R_INT_STS_MASK;

	esas2r_enable_chip_interrupts(a);

	if (likely(atomic_read(&a->disable_cnt) == 0))
		esas2r_do_deferred_processes(a);
}

irqreturn_t esas2r_msi_interrupt(int irq, void *dev_id)
{
	struct esas2r_adapter *a = (struct esas2r_adapter *)dev_id;
	u32 intstat;
	u32 doorbell;

	intstat = esas2r_read_register_dword(a, MU_INT_STATUS_OUT);

	if (likely(intstat & MU_INTSTAT_POST_OUT)) {
		/* clear the interrupt */

		esas2r_write_register_dword(a, MU_OUT_LIST_INT_STAT,
					    MU_OLIS_INT);
		esas2r_flush_register_dword(a, MU_OUT_LIST_INT_STAT);

		esas2r_get_outbound_responses(a);
	}

	if (unlikely(intstat & MU_INTSTAT_DRBL)) {
		doorbell = esas2r_read_register_dword(a, MU_DOORBELL_OUT);
		if (doorbell != 0)
			esas2r_doorbell_interrupt(a, doorbell);
	}

	/*
	 * Work around a chip bug and force a new MSI to be sent if one is
	 * still pending.
	 */
	esas2r_disable_chip_interrupts(a);
	esas2r_enable_chip_interrupts(a);

	if (likely(atomic_read(&a->disable_cnt) == 0))
		esas2r_do_deferred_processes(a);

	esas2r_do_tasklet_tasks(a);

	return 1;
}



static void esas2r_handle_outbound_rsp_err(struct esas2r_adapter *a,
					   struct esas2r_request *rq,
					   struct atto_vda_ob_rsp *rsp)
{

	/*
	 * For I/O requests, only copy the response if an error
	 * occurred and setup a callback to do error processing.
	 */
	if (unlikely(rq->req_stat != RS_SUCCESS)) {
		memcpy(&rq->func_rsp, &rsp->func_rsp, sizeof(rsp->func_rsp));

		if (rq->req_stat == RS_ABORTED) {
			if (rq->timeout > RQ_MAX_TIMEOUT)
				rq->req_stat = RS_TIMEOUT;
		} else if (rq->req_stat == RS_SCSI_ERROR) {
			u8 scsistatus = rq->func_rsp.scsi_rsp.scsi_stat;

			esas2r_trace("scsistatus: %x", scsistatus);

			/* Any of these are a good result. */
			if (scsistatus == SAM_STAT_GOOD || scsistatus ==
			    SAM_STAT_CONDITION_MET || scsistatus ==
			    SAM_STAT_INTERMEDIATE || scsistatus ==
			    SAM_STAT_INTERMEDIATE_CONDITION_MET) {
				rq->req_stat = RS_SUCCESS;
				rq->func_rsp.scsi_rsp.scsi_stat =
					SAM_STAT_GOOD;
			}
		}
	}
}

static void esas2r_get_outbound_responses(struct esas2r_adapter *a)
{
	struct atto_vda_ob_rsp *rsp;
	u32 rspput_ptr;
	u32 rspget_ptr;
	struct esas2r_request *rq;
	u32 handle;
	unsigned long flags;

	LIST_HEAD(comp_list);

	esas2r_trace_enter();

	spin_lock_irqsave(&a->queue_lock, flags);

	/* Get the outbound limit and pointers */
	rspput_ptr = le32_to_cpu(*a->outbound_copy) & MU_OLC_WRT_PTR;
	rspget_ptr = a->last_read;

	esas2r_trace("rspput_ptr: %x, rspget_ptr: %x", rspput_ptr, rspget_ptr);

	/* If we don't have anything to process, get out */
	if (unlikely(rspget_ptr == rspput_ptr)) {
		spin_unlock_irqrestore(&a->queue_lock, flags);
		esas2r_trace_exit();
		return;
	}

	/* Make sure the firmware is healthy */
	if (unlikely(rspput_ptr >= a->list_size)) {
		spin_unlock_irqrestore(&a->queue_lock, flags);
		esas2r_bugon();
		esas2r_local_reset_adapter(a);
		esas2r_trace_exit();
		return;
	}

	do {
		rspget_ptr++;

		if (rspget_ptr >= a->list_size)
			rspget_ptr = 0;

		rsp = (struct atto_vda_ob_rsp *)a->outbound_list_md.virt_addr
		      + rspget_ptr;

		handle = rsp->handle;

		/* Verify the handle range */
		if (unlikely(LOWORD(handle) == 0
			     || LOWORD(handle) > num_requests +
			     num_ae_requests + 1)) {
			esas2r_bugon();
			continue;
		}

		/* Get the request for this handle */
		rq = a->req_table[LOWORD(handle)];

		if (unlikely(rq == NULL || rq->vrq->scsi.handle != handle)) {
			esas2r_bugon();
			continue;
		}

		list_del(&rq->req_list);

		/* Get the completion status */
		rq->req_stat = rsp->req_stat;

		esas2r_trace("handle: %x", handle);
		esas2r_trace("rq: %p", rq);
		esas2r_trace("req_status: %x", rq->req_stat);

		if (likely(rq->vrq->scsi.function == VDA_FUNC_SCSI)) {
			esas2r_handle_outbound_rsp_err(a, rq, rsp);
		} else {
			/*
			 * Copy the outbound completion struct for non-I/O
			 * requests.
			 */
			memcpy(&rq->func_rsp, &rsp->func_rsp,
			       sizeof(rsp->func_rsp));
		}

		/* Queue the request for completion. */
		list_add_tail(&rq->comp_list, &comp_list);

	} while (rspget_ptr != rspput_ptr);

	a->last_read = rspget_ptr;
	spin_unlock_irqrestore(&a->queue_lock, flags);

	esas2r_comp_list_drain(a, &comp_list);
	esas2r_trace_exit();
}

/*
 * Perform all deferred processes for the adapter.  Deferred
 * processes can only be done while the current interrupt
 * disable_cnt for the adapter is zero.
 */
void esas2r_do_deferred_processes(struct esas2r_adapter *a)
{
	int startreqs = 2;
	struct esas2r_request *rq;
	unsigned long flags;

	/*
	 * startreqs is used to control starting requests
	 * that are on the deferred queue
	 *  = 0 - do not start any requests
	 *  = 1 - can start discovery requests
	 *  = 2 - can start any request
	 */

	if (test_bit(AF_CHPRST_PENDING, &a->flags) ||
	    test_bit(AF_FLASHING, &a->flags))
		startreqs = 0;
	else if (test_bit(AF_DISC_PENDING, &a->flags))
		startreqs = 1;

	atomic_inc(&a->disable_cnt);

	/* Clear off the completed list to be processed later. */

	if (esas2r_is_tasklet_pending(a)) {
		esas2r_schedule_tasklet(a);

		startreqs = 0;
	}

	/*
	 * If we can start requests then traverse the defer queue
	 * looking for requests to start or complete
	 */
	if (startreqs && !list_empty(&a->defer_list)) {
		LIST_HEAD(comp_list);
		struct list_head *element, *next;

		spin_lock_irqsave(&a->queue_lock, flags);

		list_for_each_safe(element, next, &a->defer_list) {
			rq = list_entry(element, struct esas2r_request,
					req_list);

			if (rq->req_stat != RS_PENDING) {
				list_del(element);
				list_add_tail(&rq->comp_list, &comp_list);
			}
			/*
			 * Process discovery and OS requests separately.  We
			 * can't hold up discovery requests when discovery is
			 * pending.  In general, there may be different sets of
			 * conditions for starting different types of requests.
			 */
			else if (rq->req_type == RT_DISC_REQ) {
				list_del(element);
				esas2r_disc_local_start_request(a, rq);
			} else if (startreqs == 2) {
				list_del(element);
				esas2r_local_start_request(a, rq);

				/*
				 * Flashing could have been set by last local
				 * start
				 */
				if (test_bit(AF_FLASHING, &a->flags))
					break;
			}
		}

		spin_unlock_irqrestore(&a->queue_lock, flags);
		esas2r_comp_list_drain(a, &comp_list);
	}

	atomic_dec(&a->disable_cnt);
}

/*
 * Process an adapter reset (or one that is about to happen)
 * by making sure all outstanding requests are completed that
 * haven't been already.
 */
void esas2r_process_adapter_reset(struct esas2r_adapter *a)
{
	struct esas2r_request *rq = &a->general_req;
	unsigned long flags;
	struct esas2r_disc_context *dc;

	LIST_HEAD(comp_list);
	struct list_head *element;

	esas2r_trace_enter();

	spin_lock_irqsave(&a->queue_lock, flags);

	/* abort the active discovery, if any.   */

	if (rq->interrupt_cx) {
		dc = (struct esas2r_disc_context *)rq->interrupt_cx;

		dc->disc_evt = 0;

		clear_bit(AF_DISC_IN_PROG, &a->flags);
	}

	/*
	 * just clear the interrupt callback for now.  it will be dequeued if
	 * and when we find it on the active queue and we don't want the
	 * callback called.  also set the dummy completion callback in case we
	 * were doing an I/O request.
	 */

	rq->interrupt_cx = NULL;
	rq->interrupt_cb = NULL;

	rq->comp_cb = esas2r_dummy_complete;

	/* Reset the read and write pointers */

	*a->outbound_copy =
		a->last_write =
			a->last_read = a->list_size - 1;

	set_bit(AF_COMM_LIST_TOGGLE, &a->flags);

	/* Kill all the requests on the active list */
	list_for_each(element, &a->defer_list) {
		rq = list_entry(element, struct esas2r_request, req_list);

		if (rq->req_stat == RS_STARTED)
			if (esas2r_ioreq_aborted(a, rq, RS_ABORTED))
				list_add_tail(&rq->comp_list, &comp_list);
	}

	spin_unlock_irqrestore(&a->queue_lock, flags);
	esas2r_comp_list_drain(a, &comp_list);
	esas2r_process_bus_reset(a);
	esas2r_trace_exit();
}

static void esas2r_process_bus_reset(struct esas2r_adapter *a)
{
	struct esas2r_request *rq;
	struct list_head *element;
	unsigned long flags;

	LIST_HEAD(comp_list);

	esas2r_trace_enter();

	esas2r_hdebug("reset detected");

	spin_lock_irqsave(&a->queue_lock, flags);

	/* kill all the requests on the deferred queue */
	list_for_each(element, &a->defer_list) {
		rq = list_entry(element, struct esas2r_request, req_list);
		if (esas2r_ioreq_aborted(a, rq, RS_ABORTED))
			list_add_tail(&rq->comp_list, &comp_list);
	}

	spin_unlock_irqrestore(&a->queue_lock, flags);

	esas2r_comp_list_drain(a, &comp_list);

	if (atomic_read(&a->disable_cnt) == 0)
		esas2r_do_deferred_processes(a);

	clear_bit(AF_OS_RESET, &a->flags);

	esas2r_trace_exit();
}

static void esas2r_chip_rst_needed_during_tasklet(struct esas2r_adapter *a)
{

	clear_bit(AF_CHPRST_NEEDED, &a->flags);
	clear_bit(AF_BUSRST_NEEDED, &a->flags);
	clear_bit(AF_BUSRST_DETECTED, &a->flags);
	clear_bit(AF_BUSRST_PENDING, &a->flags);
	/*
	 * Make sure we don't get attempt more than 3 resets
	 * when the uptime between resets does not exceed one
	 * minute.  This will stop any situation where there is
	 * really something wrong with the hardware.  The way
	 * this works is that we start with uptime ticks at 0.
	 * Each time we do a reset, we add 20 seconds worth to
	 * the count.  Each time a timer tick occurs, as long
	 * as a chip reset is not pending, we decrement the
	 * tick count.  If the uptime ticks ever gets to 60
	 * seconds worth, we disable the adapter from that
	 * point forward.  Three strikes, you're out.
	 */
	if (!esas2r_is_adapter_present(a) || (a->chip_uptime >=
					      ESAS2R_CHP_UPTIME_MAX)) {
		esas2r_hdebug("*** adapter disabled ***");

		/*
		 * Ok, some kind of hard failure.  Make sure we
		 * exit this loop with chip interrupts
		 * permanently disabled so we don't lock up the
		 * entire system.  Also flag degraded mode to
		 * prevent the heartbeat from trying to recover.
		 */

		set_bit(AF_DEGRADED_MODE, &a->flags);
		set_bit(AF_DISABLED, &a->flags);
		clear_bit(AF_CHPRST_PENDING, &a->flags);
		clear_bit(AF_DISC_PENDING, &a->flags);

		esas2r_disable_chip_interrupts(a);
		a->int_mask = 0;
		esas2r_process_adapter_reset(a);

		esas2r_log(ESAS2R_LOG_CRIT,
			   "Adapter disabled because of hardware failure");
	} else {
		bool alrdyrst = test_and_set_bit(AF_CHPRST_STARTED, &a->flags);

		if (!alrdyrst)
			/*
			 * Only disable interrupts if this is
			 * the first reset attempt.
			 */
			esas2r_disable_chip_interrupts(a);

		if ((test_bit(AF_POWER_MGT, &a->flags)) &&
		    !test_bit(AF_FIRST_INIT, &a->flags) && !alrdyrst) {
			/*
			 * Don't reset the chip on the first
			 * deferred power up attempt.
			 */
		} else {
			esas2r_hdebug("*** resetting chip ***");
			esas2r_reset_chip(a);
		}

		/* Kick off the reinitialization */
		a->chip_uptime += ESAS2R_CHP_UPTIME_CNT;
		a->chip_init_time = jiffies_to_msecs(jiffies);
		if (!test_bit(AF_POWER_MGT, &a->flags)) {
			esas2r_process_adapter_reset(a);

			if (!alrdyrst) {
				/* Remove devices now that I/O is cleaned up. */
				a->prev_dev_cnt =
					esas2r_targ_db_get_tgt_cnt(a);
				esas2r_targ_db_remove_all(a, false);
			}
		}

		a->int_mask = 0;
	}
}

static void esas2r_handle_chip_rst_during_tasklet(struct esas2r_adapter *a)
{
	while (test_bit(AF_CHPRST_DETECTED, &a->flags)) {
		/*
		 * Balance the enable in esas2r_initadapter_hw.
		 * Esas2r_power_down already took care of it for power
		 * management.
		 */
		if (!test_bit(AF_DEGRADED_MODE, &a->flags) &&
		    !test_bit(AF_POWER_MGT, &a->flags))
			esas2r_disable_chip_interrupts(a);

		/* Reinitialize the chip. */
		esas2r_check_adapter(a);
		esas2r_init_adapter_hw(a, 0);

		if (test_bit(AF_CHPRST_NEEDED, &a->flags))
			break;

		if (test_bit(AF_POWER_MGT, &a->flags)) {
			/* Recovery from power management. */
			if (test_bit(AF_FIRST_INIT, &a->flags)) {
				/* Chip reset during normal power up */
				esas2r_log(ESAS2R_LOG_CRIT,
					   "The firmware was reset during a normal power-up sequence");
			} else {
				/* Deferred power up complete. */
				clear_bit(AF_POWER_MGT, &a->flags);
				esas2r_send_reset_ae(a, true);
			}
		} else {
			/* Recovery from online chip reset. */
			if (test_bit(AF_FIRST_INIT, &a->flags)) {
				/* Chip reset during driver load */
			} else {
				/* Chip reset after driver load */
				esas2r_send_reset_ae(a, false);
			}

			esas2r_log(ESAS2R_LOG_CRIT,
				   "Recovering from a chip reset while the chip was online");
		}

		clear_bit(AF_CHPRST_STARTED, &a->flags);
		esas2r_enable_chip_interrupts(a);

		/*
		 * Clear this flag last!  this indicates that the chip has been
		 * reset already during initialization.
		 */
		clear_bit(AF_CHPRST_DETECTED, &a->flags);
	}
}


/* Perform deferred tasks when chip interrupts are disabled */
void esas2r_do_tasklet_tasks(struct esas2r_adapter *a)
{

	if (test_bit(AF_CHPRST_NEEDED, &a->flags) ||
	    test_bit(AF_CHPRST_DETECTED, &a->flags)) {
		if (test_bit(AF_CHPRST_NEEDED, &a->flags))
			esas2r_chip_rst_needed_during_tasklet(a);

		esas2r_handle_chip_rst_during_tasklet(a);
	}

	if (test_bit(AF_BUSRST_NEEDED, &a->flags)) {
		esas2r_hdebug("hard resetting bus");

		clear_bit(AF_BUSRST_NEEDED, &a->flags);

		if (test_bit(AF_FLASHING, &a->flags))
			set_bit(AF_BUSRST_DETECTED, &a->flags);
		else
			esas2r_write_register_dword(a, MU_DOORBELL_IN,
						    DRBL_RESET_BUS);
	}

	if (test_bit(AF_BUSRST_DETECTED, &a->flags)) {
		esas2r_process_bus_reset(a);

		esas2r_log_dev(ESAS2R_LOG_WARN,
			       &(a->host->shost_gendev),
			       "scsi_report_bus_reset() called");

		scsi_report_bus_reset(a->host, 0);

		clear_bit(AF_BUSRST_DETECTED, &a->flags);
		clear_bit(AF_BUSRST_PENDING, &a->flags);

		esas2r_log(ESAS2R_LOG_WARN, "Bus reset complete");
	}

	if (test_bit(AF_PORT_CHANGE, &a->flags)) {
		clear_bit(AF_PORT_CHANGE, &a->flags);

		esas2r_targ_db_report_changes(a);
	}

	if (atomic_read(&a->disable_cnt) == 0)
		esas2r_do_deferred_processes(a);
}

static void esas2r_doorbell_interrupt(struct esas2r_adapter *a, u32 doorbell)
{
	if (!(doorbell & DRBL_FORCE_INT)) {
		esas2r_trace_enter();
		esas2r_trace("doorbell: %x", doorbell);
	}

	/* First clear the doorbell bits */
	esas2r_write_register_dword(a, MU_DOORBELL_OUT, doorbell);

	if (doorbell & DRBL_RESET_BUS)
		set_bit(AF_BUSRST_DETECTED, &a->flags);

	if (doorbell & DRBL_FORCE_INT)
		clear_bit(AF_HEARTBEAT, &a->flags);

	if (doorbell & DRBL_PANIC_REASON_MASK) {
		esas2r_hdebug("*** Firmware Panic ***");
		esas2r_log(ESAS2R_LOG_CRIT, "The firmware has panicked");
	}

	if (doorbell & DRBL_FW_RESET) {
		set_bit(AF2_COREDUMP_AVAIL, &a->flags2);
		esas2r_local_reset_adapter(a);
	}

	if (!(doorbell & DRBL_FORCE_INT))
		esas2r_trace_exit();
}

void esas2r_force_interrupt(struct esas2r_adapter *a)
{
	esas2r_write_register_dword(a, MU_DOORBELL_IN, DRBL_FORCE_INT |
				    DRBL_DRV_VER);
}


static void esas2r_lun_event(struct esas2r_adapter *a, union atto_vda_ae *ae,
			     u16 target, u32 length)
{
	struct esas2r_target *t = a->targetdb + target;
	u32 cplen = length;
	unsigned long flags;

	if (cplen > sizeof(t->lu_event))
		cplen = sizeof(t->lu_event);

	esas2r_trace("ae->lu.dwevent: %x", ae->lu.dwevent);
	esas2r_trace("ae->lu.bystate: %x", ae->lu.bystate);

	spin_lock_irqsave(&a->mem_lock, flags);

	t->new_target_state = TS_INVALID;

	if (ae->lu.dwevent  & VDAAE_LU_LOST) {
		t->new_target_state = TS_NOT_PRESENT;
	} else {
		switch (ae->lu.bystate) {
		case VDAAE_LU_NOT_PRESENT:
		case VDAAE_LU_OFFLINE:
		case VDAAE_LU_DELETED:
		case VDAAE_LU_FACTORY_DISABLED:
			t->new_target_state = TS_NOT_PRESENT;
			break;

		case VDAAE_LU_ONLINE:
		case VDAAE_LU_DEGRADED:
			t->new_target_state = TS_PRESENT;
			break;
		}
	}

	if (t->new_target_state != TS_INVALID) {
		memcpy(&t->lu_event, &ae->lu, cplen);

		esas2r_disc_queue_event(a, DCDE_DEV_CHANGE);
	}

	spin_unlock_irqrestore(&a->mem_lock, flags);
}



void esas2r_ae_complete(struct esas2r_adapter *a, struct esas2r_request *rq)
{
	union atto_vda_ae *ae =
		(union atto_vda_ae *)rq->vda_rsp_data->ae_data.event_data;
	u32 length = le32_to_cpu(rq->func_rsp.ae_rsp.length);
	union atto_vda_ae *last =
		(union atto_vda_ae *)(rq->vda_rsp_data->ae_data.event_data
				      + length);

	esas2r_trace_enter();
	esas2r_trace("length: %d", length);

	if (length > sizeof(struct atto_vda_ae_data)
	    || (length & 3) != 0
	    || length == 0) {
		esas2r_log(ESAS2R_LOG_WARN,
			   "The AE request response length (%p) is too long: %d",
			   rq, length);

		esas2r_hdebug("aereq->length (0x%x) too long", length);
		esas2r_bugon();

		last = ae;
	}

	while (ae < last) {
		u16 target;

		esas2r_trace("ae: %p", ae);
		esas2r_trace("ae->hdr: %p", &(ae->hdr));

		length = ae->hdr.bylength;

		if (length > (u32)((u8 *)last - (u8 *)ae)
		    || (length & 3) != 0
		    || length == 0) {
			esas2r_log(ESAS2R_LOG_CRIT,
				   "the async event length is invalid (%p): %d",
				   ae, length);

			esas2r_hdebug("ae->hdr.length (0x%x) invalid", length);
			esas2r_bugon();

			break;
		}

		esas2r_nuxi_ae_data(ae);

		esas2r_queue_fw_event(a, fw_event_vda_ae, ae,
				      sizeof(union atto_vda_ae));

		switch (ae->hdr.bytype) {
		case VDAAE_HDR_TYPE_RAID:

			if (ae->raid.dwflags & (VDAAE_GROUP_STATE
						| VDAAE_RBLD_STATE
						| VDAAE_MEMBER_CHG
						| VDAAE_PART_CHG)) {
				esas2r_log(ESAS2R_LOG_INFO,
					   "RAID event received - name:%s rebuild_state:%d group_state:%d",
					   ae->raid.acname,
					   ae->raid.byrebuild_state,
					   ae->raid.bygroup_state);
			}

			break;

		case VDAAE_HDR_TYPE_LU:
			esas2r_log(ESAS2R_LOG_INFO,
				   "LUN event received: event:%d target_id:%d LUN:%d state:%d",
				   ae->lu.dwevent,
				   ae->lu.id.tgtlun.wtarget_id,
				   ae->lu.id.tgtlun.bylun,
				   ae->lu.bystate);

			target = ae->lu.id.tgtlun.wtarget_id;

			if (target < ESAS2R_MAX_TARGETS)
				esas2r_lun_event(a, ae, target, length);

			break;

		case VDAAE_HDR_TYPE_DISK:
			esas2r_log(ESAS2R_LOG_INFO, "Disk event received");
			break;

		default:

			/* Silently ignore the rest and let the apps deal with
			 * them.
			 */

			break;
		}

		ae = (union atto_vda_ae *)((u8 *)ae + length);
	}

	/* Now requeue it. */
	esas2r_start_ae_request(a, rq);
	esas2r_trace_exit();
}

/* Send an asynchronous event for a chip reset or power management. */
void esas2r_send_reset_ae(struct esas2r_adapter *a, bool pwr_mgt)
{
	struct atto_vda_ae_hdr ae;

	if (pwr_mgt)
		ae.bytype = VDAAE_HDR_TYPE_PWRMGT;
	else
		ae.bytype = VDAAE_HDR_TYPE_RESET;

	ae.byversion = VDAAE_HDR_VER_0;
	ae.byflags = 0;
	ae.bylength = (u8)sizeof(struct atto_vda_ae_hdr);

	if (pwr_mgt)
		esas2r_hdebug("*** sending power management AE ***");
	else
		esas2r_hdebug("*** sending reset AE ***");

	esas2r_queue_fw_event(a, fw_event_vda_ae, &ae,
			      sizeof(union atto_vda_ae));
}

void esas2r_dummy_complete(struct esas2r_adapter *a, struct esas2r_request *rq)
{}

static void esas2r_check_req_rsp_sense(struct esas2r_adapter *a,
				       struct esas2r_request *rq)
{
	u8 snslen, snslen2;

	snslen = snslen2 = rq->func_rsp.scsi_rsp.sense_len;

	if (snslen > rq->sense_len)
		snslen = rq->sense_len;

	if (snslen) {
		if (rq->sense_buf)
			memcpy(rq->sense_buf, rq->data_buf, snslen);
		else
			rq->sense_buf = (u8 *)rq->data_buf;

		/* See about possible sense data */
		if (snslen2 > 0x0c) {
			u8 *s = (u8 *)rq->data_buf;

			esas2r_trace_enter();

			/* Report LUNS data has changed */
			if (s[0x0c] == 0x3f && s[0x0d] == 0x0E) {
				esas2r_trace("rq->target_id: %d",
					     rq->target_id);
				esas2r_target_state_changed(a, rq->target_id,
							    TS_LUN_CHANGE);
			}

			esas2r_trace("add_sense_key=%x", s[0x0c]);
			esas2r_trace("add_sense_qual=%x", s[0x0d]);
			esas2r_trace_exit();
		}
	}

	rq->sense_len = snslen;
}


void esas2r_complete_request(struct esas2r_adapter *a,
			     struct esas2r_request *rq)
{
	if (rq->vrq->scsi.function == VDA_FUNC_FLASH
	    && rq->vrq->flash.sub_func == VDA_FLASH_COMMIT)
		clear_bit(AF_FLASHING, &a->flags);

	/* See if we setup a callback to do special processing */

	if (rq->interrupt_cb) {
		(*rq->interrupt_cb)(a, rq);

		if (rq->req_stat == RS_PENDING) {
			esas2r_start_request(a, rq);
			return;
		}
	}

	if (likely(rq->vrq->scsi.function == VDA_FUNC_SCSI)
	    && unlikely(rq->req_stat != RS_SUCCESS)) {
		esas2r_check_req_rsp_sense(a, rq);
		esas2r_log_request_failure(a, rq);
	}

	(*rq->comp_cb)(a, rq);
}