return len;
 }
 
+static ssize_t
+qla2x00_zio_show(struct class_device *cdev, char *buf)
+{
+       scsi_qla_host_t *ha = to_qla_host(class_to_shost(cdev));
+       int len = 0;
+
+       switch (ha->zio_mode) {
+       case QLA_ZIO_MODE_5:
+               len += snprintf(buf + len, PAGE_SIZE-len, "Mode 5\n");
+               break;
+       case QLA_ZIO_MODE_6:
+               len += snprintf(buf + len, PAGE_SIZE-len, "Mode 6\n");
+               break;
+       case QLA_ZIO_DISABLED:
+               len += snprintf(buf + len, PAGE_SIZE-len, "Disabled\n");
+               break;
+       }
+       return len;
+}
+
+static ssize_t
+qla2x00_zio_store(struct class_device *cdev, const char *buf, size_t count)
+{
+       scsi_qla_host_t *ha = to_qla_host(class_to_shost(cdev));
+       int val = 0;
+       uint16_t zio_mode;
+
+       if (sscanf(buf, "%d", &val) != 1)
+               return -EINVAL;
+
+       switch (val) {
+       case 1:
+               zio_mode = QLA_ZIO_MODE_5;
+               break;
+       case 2:
+               zio_mode = QLA_ZIO_MODE_6;
+               break;
+       default:
+               zio_mode = QLA_ZIO_DISABLED;
+               break;
+       }
+
+       /* Update per-hba values and queue a reset. */
+       if (zio_mode != QLA_ZIO_DISABLED || ha->zio_mode != QLA_ZIO_DISABLED) {
+               ha->zio_mode = zio_mode;
+               set_bit(ISP_ABORT_NEEDED, &ha->dpc_flags);
+       }
+       return strlen(buf);
+}
+
+static ssize_t
+qla2x00_zio_timer_show(struct class_device *cdev, char *buf)
+{
+       scsi_qla_host_t *ha = to_qla_host(class_to_shost(cdev));
+
+       return snprintf(buf, PAGE_SIZE, "%d us\n", ha->zio_timer * 100);
+}
+
+static ssize_t
+qla2x00_zio_timer_store(struct class_device *cdev, const char *buf,
+    size_t count)
+{
+       scsi_qla_host_t *ha = to_qla_host(class_to_shost(cdev));
+       int val = 0;
+       uint16_t zio_timer;
+
+       if (sscanf(buf, "%d", &val) != 1)
+               return -EINVAL;
+       if (val > 25500 || val < 100)
+               return -ERANGE;
+
+       zio_timer = (uint16_t)(val / 100);
+       ha->zio_timer = zio_timer;
+
+       return strlen(buf);
+}
+
 static CLASS_DEVICE_ATTR(driver_version, S_IRUGO, qla2x00_drvr_version_show,
        NULL);
 static CLASS_DEVICE_ATTR(fw_version, S_IRUGO, qla2x00_fw_version_show, NULL);
 static CLASS_DEVICE_ATTR(model_desc, S_IRUGO, qla2x00_model_desc_show, NULL);
 static CLASS_DEVICE_ATTR(pci_info, S_IRUGO, qla2x00_pci_info_show, NULL);
 static CLASS_DEVICE_ATTR(state, S_IRUGO, qla2x00_state_show, NULL);
+static CLASS_DEVICE_ATTR(zio, S_IRUGO | S_IWUSR, qla2x00_zio_show,
+    qla2x00_zio_store);
+static CLASS_DEVICE_ATTR(zio_timer, S_IRUGO | S_IWUSR, qla2x00_zio_timer_show,
+    qla2x00_zio_timer_store);
 
 struct class_device_attribute *qla2x00_host_attrs[] = {
        &class_device_attr_driver_version,
        &class_device_attr_model_desc,
        &class_device_attr_pci_info,
        &class_device_attr_state,
+       &class_device_attr_zio,
+       &class_device_attr_zio_timer,
        NULL,
 };
 
 
 #define PD_STATE_WAIT_PORT_LOGOUT_ACK          11
 
 
+#define QLA_ZIO_MODE_5         (BIT_2 | BIT_0)
+#define QLA_ZIO_MODE_6         (BIT_2 | BIT_1)
+#define QLA_ZIO_DISABLED       0
+#define QLA_ZIO_DEFAULT_TIMER  2
+
 /*
  * ISP Initialization Control Block.
  * Little endian except where noted.
        /* Needed for BEACON */
        uint16_t        beacon_blink_led;
        uint16_t        beacon_green_on;
+
+       uint16_t        zio_mode;
+       uint16_t        zio_timer;
 } scsi_qla_host_t;
 
 
 
 extern int ql2xlogintimeout;
 extern int qlport_down_retry;
 extern int ql2xplogiabsentdevice;
-extern int ql2xenablezio;
-extern int ql2xintrdelaytimer;
 extern int ql2xloginretrycount;
 extern int ql2xfdmienable;
 
 extern irqreturn_t qla2300_intr_handler(int, void *, struct pt_regs *);
 extern irqreturn_t qla24xx_intr_handler(int, void *, struct pt_regs *);
 extern void qla2x00_process_response_queue(struct scsi_qla_host *);
+extern void qla24xx_process_response_queue(struct scsi_qla_host *);
 
 /*
  * Global Function Prototypes in qla_sup.c source file.
 
        nvram_t         *nv = (nvram_t *)ha->request_ring;
        uint8_t         *ptr = (uint8_t *)ha->request_ring;
        struct device_reg_2xxx __iomem *reg = &ha->iobase->isp;
-       uint8_t         timer_mode;
 
        rval = QLA_SUCCESS;
 
 
                ha->flags.process_response_queue = 1;
        } else {
-               /* Enable ZIO -- Support mode 5 only. */
-               timer_mode = icb->add_firmware_options[0] &
-                   (BIT_3 | BIT_2 | BIT_1 | BIT_0);
+               /* Enable ZIO. */
+               if (!ha->flags.init_done) {
+                       ha->zio_mode = icb->add_firmware_options[0] &
+                           (BIT_3 | BIT_2 | BIT_1 | BIT_0);
+                       ha->zio_timer = icb->interrupt_delay_timer ?
+                           icb->interrupt_delay_timer: 2;
+               }
                icb->add_firmware_options[0] &=
                    ~(BIT_3 | BIT_2 | BIT_1 | BIT_0);
-               if (ql2xenablezio)
-                       timer_mode = BIT_2 | BIT_0;
-               if (timer_mode == (BIT_2 | BIT_0)) {
-                       DEBUG2(printk("scsi(%ld): ZIO enabled; timer delay "
-                           "(%d).\n", ha->host_no, ql2xintrdelaytimer));
+               ha->flags.process_response_queue = 0;
+               if (ha->zio_mode != QLA_ZIO_DISABLED) {
+                       DEBUG2(printk("scsi(%ld): ZIO mode %d enabled; timer "
+                           "delay (%d us).\n", ha->host_no, ha->zio_mode,
+                           ha->zio_timer * 100));
                        qla_printk(KERN_INFO, ha,
-                           "ZIO enabled; timer delay (%d).\n",
-                           ql2xintrdelaytimer);
+                           "ZIO mode %d enabled; timer delay (%d us).\n",
+                           ha->zio_mode, ha->zio_timer * 100);
 
-                       icb->add_firmware_options[0] |= timer_mode;
-                       icb->interrupt_delay_timer = ql2xintrdelaytimer;
+                       icb->add_firmware_options[0] |= (uint8_t)ha->zio_mode;
+                       icb->interrupt_delay_timer = (uint8_t)ha->zio_timer;
                        ha->flags.process_response_queue = 1;
                }
        }
        if (ql2xloginretrycount)
                ha->login_retry_count = ql2xloginretrycount;
 
+       /* Enable ZIO. */
+       if (!ha->flags.init_done) {
+               ha->zio_mode = le32_to_cpu(icb->firmware_options_2) &
+                   (BIT_3 | BIT_2 | BIT_1 | BIT_0);
+               ha->zio_timer = le16_to_cpu(icb->interrupt_delay_timer) ?
+                   le16_to_cpu(icb->interrupt_delay_timer): 2;
+       }
+       icb->firmware_options_2 &= __constant_cpu_to_le32(
+           ~(BIT_3 | BIT_2 | BIT_1 | BIT_0));
+       ha->flags.process_response_queue = 0;
+       if (ha->zio_mode != QLA_ZIO_DISABLED) {
+               DEBUG2(printk("scsi(%ld): ZIO mode %d enabled; timer delay "
+                   "(%d us).\n", ha->host_no, ha->zio_mode,
+                   ha->zio_timer * 100));
+               qla_printk(KERN_INFO, ha,
+                   "ZIO mode %d enabled; timer delay (%d us).\n",
+                   ha->zio_mode, ha->zio_timer * 100);
+
+               icb->firmware_options_2 |= cpu_to_le32(
+                   (uint32_t)ha->zio_mode);
+               icb->interrupt_delay_timer = cpu_to_le16(ha->zio_timer);
+               ha->flags.process_response_queue = 1;
+       }
+
        if (rval) {
                DEBUG2_3(printk(KERN_WARNING
                    "scsi(%ld): NVRAM configuration failed!\n", ha->host_no));
 
        WRT_REG_WORD(ISP_REQ_Q_IN(ha, reg), ha->req_ring_index);
        RD_REG_WORD_RELAXED(ISP_REQ_Q_IN(ha, reg));     /* PCI Posting. */
 
+       /* Manage unprocessed RIO/ZIO commands in response queue. */
+       if (ha->flags.process_response_queue &&
+           ha->response_ring_ptr->signature != RESPONSE_PROCESSED)
+               qla2x00_process_response_queue(ha);
+
        spin_unlock_irqrestore(&ha->hardware_lock, flags);
        return (QLA_SUCCESS);
 
        WRT_REG_DWORD(®->req_q_in, ha->req_ring_index);
        RD_REG_DWORD_RELAXED(®->req_q_in);           /* PCI Posting. */
 
+       /* Manage unprocessed RIO/ZIO commands in response queue. */
+       if (ha->flags.process_response_queue &&
+           ha->response_ring_ptr->signature != RESPONSE_PROCESSED)
+               qla24xx_process_response_queue(ha);
+
        spin_unlock_irqrestore(&ha->hardware_lock, flags);
        return QLA_SUCCESS;
 
 
 static void qla2x00_mbx_completion(scsi_qla_host_t *, uint16_t);
 static void qla2x00_async_event(scsi_qla_host_t *, uint16_t *);
 static void qla2x00_process_completed_request(struct scsi_qla_host *, uint32_t);
-void qla2x00_process_response_queue(struct scsi_qla_host *);
 static void qla2x00_status_entry(scsi_qla_host_t *, void *);
 static void qla2x00_status_cont_entry(scsi_qla_host_t *, sts_cont_entry_t *);
 static void qla2x00_error_entry(scsi_qla_host_t *, sts_entry_t *);
 static void qla2x00_ms_entry(scsi_qla_host_t *, ms_iocb_entry_t *);
 
-void qla24xx_process_response_queue(scsi_qla_host_t *);
 static void qla24xx_ms_entry(scsi_qla_host_t *, struct ct_entry_24xx *);
 
 /**
                    "scsi(%ld): [R|Z]IO update completion.\n",
                    ha->host_no));
 
-               qla2x00_process_response_queue(ha);
+               if (IS_QLA24XX(ha) || IS_QLA25XX(ha))
+                       qla24xx_process_response_queue(ha);
+               else
+                       qla2x00_process_response_queue(ha);
                break;
 
        case MBA_DISCARD_RND_FRAME:
 
                "a Fabric scan.  This is needed for several broken switches."
                "Default is 0 - no PLOGI. 1 - perfom PLOGI.");
 
-int ql2xenablezio = 0;
-module_param(ql2xenablezio, int, S_IRUGO|S_IRUSR);
-MODULE_PARM_DESC(ql2xenablezio,
-               "Option to enable ZIO:If 1 then enable it otherwise"
-               " use the default set in the NVRAM."
-               " Default is 0 : disabled");
-
-int ql2xintrdelaytimer = 10;
-module_param(ql2xintrdelaytimer, int, S_IRUGO|S_IRUSR);
-MODULE_PARM_DESC(ql2xintrdelaytimer,
-               "ZIO: Waiting time for Firmware before it generates an "
-               "interrupt to the host to notify completion of request.");
-
 int ql2xloginretrycount = 0;
 module_param(ql2xloginretrycount, int, S_IRUGO|S_IRUSR);
 MODULE_PARM_DESC(ql2xloginretrycount,
        if (rval != QLA_SUCCESS)
                goto qc_host_busy_free_sp;
 
-       /* Manage unprocessed RIO/ZIO commands in response queue. */
-       if (ha->flags.online && ha->flags.process_response_queue &&
-           ha->response_ring_ptr->signature != RESPONSE_PROCESSED) {
-               unsigned long flags;
-
-               spin_lock_irqsave(&ha->hardware_lock, flags);
-               qla2x00_process_response_queue(ha);
-               spin_unlock_irqrestore(&ha->hardware_lock, flags);
-       }
-
        spin_lock_irq(ha->host->host_lock);
 
        return 0;