diff --git a/drivers/scsi/qla2xxx/qla_dbg.c b/drivers/scsi/qla2xxx/qla_dbg.c
index 26751d34bcf2..7b74973d5788 100644
--- a/drivers/scsi/qla2xxx/qla_dbg.c
+++ b/drivers/scsi/qla2xxx/qla_dbg.c
@@ -14,7 +14,7 @@
  * | Module Init and Probe        |       0x0193       | 0x0146         |
  * |                              |                    | 0x015b-0x0160	|
  * |                              |                    | 0x016e		|
- * | Mailbox commands             |       0x1199       | 0x1193		|
+ * | Mailbox commands             |       0x1205       | 0x11a2-0x11ff	|
  * | Device Discovery             |       0x2134       | 0x210e-0x2116  |
  * |				  | 		       | 0x211a         |
  * |                              |                    | 0x211c-0x2128  |
diff --git a/drivers/scsi/qla2xxx/qla_def.h b/drivers/scsi/qla2xxx/qla_def.h
index 799d25564ed6..015908f99e76 100644
--- a/drivers/scsi/qla2xxx/qla_def.h
+++ b/drivers/scsi/qla2xxx/qla_def.h
@@ -978,6 +978,7 @@ struct mbx_cmd_32 {
 #define MBC_ABORT_TARGET		0x17	/* Abort target (ID). */
 #define MBC_RESET			0x18	/* Reset. */
 #define MBC_GET_ADAPTER_LOOP_ID		0x20	/* Get loop id of ISP2200. */
+#define MBC_GET_SET_ZIO_THRESHOLD	0x21	/* Get/SET ZIO THRESHOLD. */
 #define MBC_GET_RETRY_COUNT		0x22	/* Get f/w retry cnt/delay. */
 #define MBC_DISABLE_VI			0x24	/* Disable VI operation. */
 #define MBC_ENABLE_VI			0x25	/* Enable VI operation. */
@@ -4018,6 +4019,9 @@ struct qla_hw_data {
 
 	struct qlt_hw_data tgt;
 	int	allow_cna_fw_dump;
+
+	atomic_t        nvme_active_aen_cnt;
+	uint16_t        nvme_last_rptd_aen;             /* Last recorded aen count */
 };
 
 /*
@@ -4090,6 +4094,7 @@ typedef struct scsi_qla_host {
 #define FX00_CRITEMP_RECOVERY	25
 #define FX00_HOST_INFO_RESEND	26
 #define QPAIR_ONLINE_CHECK_NEEDED	27
+#define SET_ZIO_THRESHOLD_NEEDED	28
 
 	unsigned long	pci_flags;
 #define PFLG_DISCONNECTED	0	/* PCI device removed */
diff --git a/drivers/scsi/qla2xxx/qla_gbl.h b/drivers/scsi/qla2xxx/qla_gbl.h
index 659cdf592678..67864d4492cd 100644
--- a/drivers/scsi/qla2xxx/qla_gbl.h
+++ b/drivers/scsi/qla2xxx/qla_gbl.h
@@ -484,6 +484,9 @@ int qla24xx_gidlist_wait(struct scsi_qla_host *, void *, dma_addr_t,
 int __qla24xx_parse_gpdb(struct scsi_qla_host *, fc_port_t *,
 	struct port_database_24xx *);
 
+extern int qla27xx_get_zio_threshold(scsi_qla_host_t *, uint16_t *);
+extern int qla27xx_set_zio_threshold(scsi_qla_host_t *, uint16_t );
+
 /*
  * Global Function Prototypes in qla_isr.c source file.
  */
diff --git a/drivers/scsi/qla2xxx/qla_isr.c b/drivers/scsi/qla2xxx/qla_isr.c
index 9127eee67478..317fe6026856 100644
--- a/drivers/scsi/qla2xxx/qla_isr.c
+++ b/drivers/scsi/qla2xxx/qla_isr.c
@@ -1823,7 +1823,7 @@ qla24xx_nvme_iocb_entry(scsi_qla_host_t *vha, struct req_que *req, void *tsk)
 	nvme = &sp->u.iocb_cmd;
 
 	if (unlikely(nvme->u.nvme.aen_op))
-		atomic_dec(&sp->vha->nvme_active_aen_cnt);
+		atomic_dec(&sp->vha->hw->nvme_active_aen_cnt);
 
 	/*
 	 * State flags: Bit 6 and 0.
diff --git a/drivers/scsi/qla2xxx/qla_mbx.c b/drivers/scsi/qla2xxx/qla_mbx.c
index 7c6d1a404011..b271c3f78c85 100644
--- a/drivers/scsi/qla2xxx/qla_mbx.c
+++ b/drivers/scsi/qla2xxx/qla_mbx.c
@@ -947,20 +947,12 @@ qla2x00_get_fw_version(scsi_qla_host_t *vha)
 			    "%s: Firmware supports Exchange Offload 0x%x\n",
 			    __func__, ha->fw_attributes_h);
 
-		/* bit 26 of fw_attributes */
-		if ((ha->fw_attributes_h & 0x400) && ql2xnvmeenable) {
-			struct init_cb_24xx *icb;
-
-			icb = (struct init_cb_24xx *)ha->init_cb;
-			/*
-			 * fw supports nvme and driver load
-			 * parameter requested nvme
-			 */
+		/*
+		 * fw supports nvme and driver load parameter requested nvme
+		 * bit 26 of fw_attributes indicates NVMe support
+		 */
+		if ((ha->fw_attributes_h & 0x400) && ql2xnvmeenable)
 			vha->flags.nvme_enabled = 1;
-			icb->firmware_options_2 &= cpu_to_le32(~0xf);
-			ha->zio_mode = 0;
-			ha->zio_timer = 0;
-		}
 
 	}
 
@@ -6085,3 +6077,61 @@ int qla24xx_gidlist_wait(struct scsi_qla_host *vha,
 done:
 	return rval;
 }
+
+int qla27xx_set_zio_threshold(scsi_qla_host_t *vha, uint16_t value)
+{
+	int rval;
+	mbx_cmd_t	mc;
+	mbx_cmd_t	*mcp = &mc;
+
+	ql_dbg(ql_dbg_mbx + ql_dbg_verbose, vha, 0x1200,
+	    "Entered %s\n", __func__);
+
+	memset(mcp->mb, 0 , sizeof(mcp->mb));
+	mcp->mb[0] = MBC_GET_SET_ZIO_THRESHOLD;
+	mcp->mb[1] = cpu_to_le16(1);
+	mcp->mb[2] = cpu_to_le16(value);
+	mcp->out_mb = MBX_2|MBX_1|MBX_0;
+	mcp->in_mb = MBX_2|MBX_0;
+	mcp->tov = MBX_TOV_SECONDS;
+	mcp->flags = 0;
+
+	rval = qla2x00_mailbox_command(vha, mcp);
+	if (rval != QLA_SUCCESS) {
+		ql_dbg(ql_dbg_mbx, vha, 0x1201, "Failed=%x.\n", rval);
+	} else {
+		ql_dbg(ql_dbg_mbx + ql_dbg_verbose, vha, 0x1202,
+		    "Done %s.\n", __func__);
+	}
+
+	return rval;
+}
+
+int qla27xx_get_zio_threshold(scsi_qla_host_t *vha, uint16_t *value)
+{
+	int rval;
+	mbx_cmd_t	mc;
+	mbx_cmd_t	*mcp = &mc;
+
+	ql_dbg(ql_dbg_mbx + ql_dbg_verbose, vha, 0x1203,
+	    "Entered %s\n", __func__);
+
+	memset(mcp->mb, 0 , sizeof(mcp->mb));
+	mcp->mb[0] = MBC_GET_SET_ZIO_THRESHOLD;
+	mcp->mb[1] = cpu_to_le16(0);
+	mcp->out_mb = MBX_1|MBX_0;
+	mcp->in_mb = MBX_2|MBX_0;
+	mcp->tov = MBX_TOV_SECONDS;
+	mcp->flags = 0;
+
+	rval = qla2x00_mailbox_command(vha, mcp);
+	if (rval != QLA_SUCCESS) {
+		ql_dbg(ql_dbg_mbx, vha, 0x1204, "Failed=%x.\n", rval);
+	} else {
+		*value = mc.mb[2];
+		ql_dbg(ql_dbg_mbx + ql_dbg_verbose, vha, 0x1205,
+		    "Done %s.\n", __func__);
+	}
+
+	return rval;
+}
diff --git a/drivers/scsi/qla2xxx/qla_nvme.c b/drivers/scsi/qla2xxx/qla_nvme.c
index 7543f533edfb..4cb5bd20065a 100644
--- a/drivers/scsi/qla2xxx/qla_nvme.c
+++ b/drivers/scsi/qla2xxx/qla_nvme.c
@@ -322,6 +322,7 @@ static int qla2x00_start_nvme_mq(srb_t *sp)
 	uint16_t	avail_dsds;
 	uint32_t	*cur_dsd;
 	struct req_que *req = NULL;
+	struct rsp_que *rsp = NULL;
 	struct scsi_qla_host *vha = sp->fcport->vha;
 	struct qla_hw_data *ha = vha->hw;
 	struct qla_qpair *qpair = sp->qpair;
@@ -330,13 +331,15 @@ static int qla2x00_start_nvme_mq(srb_t *sp)
 	struct nvmefc_fcp_req *fd = nvme->u.nvme.desc;
 	uint32_t        rval = QLA_SUCCESS;
 
-	/* Setup qpair pointers */
-	req = qpair->req;
 	tot_dsds = fd->sg_cnt;
 
 	/* Acquire qpair specific lock */
 	spin_lock_irqsave(&qpair->qp_lock, flags);
 
+	/* Setup qpair pointers */
+	req = qpair->req;
+	rsp = qpair->rsp;
+
 	/* Check for room in outstanding command list. */
 	handle = req->current_outstanding_cmd;
 	for (index = 1; index < req->num_outstanding_cmds; index++) {
@@ -371,7 +374,7 @@ static int qla2x00_start_nvme_mq(srb_t *sp)
 		struct nvme_fc_cmd_iu *cmd = fd->cmdaddr;
 		if (cmd->sqe.common.opcode == nvme_admin_async_event) {
 			nvme->u.nvme.aen_op = 1;
-			atomic_inc(&vha->nvme_active_aen_cnt);
+			atomic_inc(&vha->hw->nvme_active_aen_cnt);
 		}
 	}
 
@@ -484,6 +487,11 @@ static int qla2x00_start_nvme_mq(srb_t *sp)
 	/* Set chip new ring index. */
 	WRT_REG_DWORD(req->req_q_in, req->ring_index);
 
+	/* Manage unprocessed RIO/ZIO commands in response queue. */
+	if (vha->flags.process_response_queue &&
+	    rsp->ring_ptr->signature != RESPONSE_PROCESSED)
+		qla24xx_process_response_queue(vha, rsp);
+
 queuing_error:
 	spin_unlock_irqrestore(&qpair->qp_lock, flags);
 	return rval;
diff --git a/drivers/scsi/qla2xxx/qla_os.c b/drivers/scsi/qla2xxx/qla_os.c
index 3329512b4b35..256d3a34d4ee 100644
--- a/drivers/scsi/qla2xxx/qla_os.c
+++ b/drivers/scsi/qla2xxx/qla_os.c
@@ -2751,6 +2751,8 @@ qla2x00_probe_one(struct pci_dev *pdev, const struct pci_device_id *id)
 	spin_lock_init(&ha->tgt.sess_lock);
 	spin_lock_init(&ha->tgt.atio_lock);
 
+	atomic_set(&ha->nvme_active_aen_cnt, 0);
+
 	/* Clear our data area */
 	ha->bars = bars;
 	ha->mem_only = mem_only;
@@ -5836,6 +5838,17 @@ qla2x00_do_dpc(void *data)
 			mutex_unlock(&ha->mq_lock);
 		}
 
+		if (test_and_clear_bit(SET_ZIO_THRESHOLD_NEEDED, &base_vha->dpc_flags)) {
+			ql_log(ql_log_info, base_vha, 0xffffff,
+				"nvme: SET ZIO Activity exchange threshold to %d.\n",
+						ha->nvme_last_rptd_aen);
+			if (qla27xx_set_zio_threshold(base_vha, ha->nvme_last_rptd_aen)) {
+				ql_log(ql_log_info, base_vha, 0xffffff,
+					"nvme: Unable to SET ZIO Activity exchange threshold to %d.\n",
+						ha->nvme_last_rptd_aen);
+			}
+		}
+
 		if (!IS_QLAFX00(ha))
 			qla2x00_do_dpc_all_vps(base_vha);
 
@@ -6033,12 +6046,15 @@ qla2x00_timer(scsi_qla_host_t *vha)
 	 * FC-NVME
 	 * see if the active AEN count has changed from what was last reported.
 	 */
-	if (atomic_read(&vha->nvme_active_aen_cnt) != vha->nvme_last_rptd_aen) {
-		vha->nvme_last_rptd_aen =
-		    atomic_read(&vha->nvme_active_aen_cnt);
+	if (!vha->vp_idx &&
+		atomic_read(&ha->nvme_active_aen_cnt) != ha->nvme_last_rptd_aen &&
+		ha->zio_mode == QLA_ZIO_MODE_6) {
 		ql_log(ql_log_info, vha, 0x3002,
-		    "reporting new aen count of %d to the fw\n",
-		    vha->nvme_last_rptd_aen);
+			"nvme: Sched: Set ZIO exchange threshold to %d.\n",
+			ha->nvme_last_rptd_aen);
+		ha->nvme_last_rptd_aen = atomic_read(&ha->nvme_active_aen_cnt);
+		set_bit(SET_ZIO_THRESHOLD_NEEDED, &vha->dpc_flags);
+		start_dpc++;
 	}
 
 	/* Schedule the DPC routine if needed */
