[SCSI] qla4xxx: Fix processing response queue during probe

Issue:
While booting with kdump kernel, driver receive IOCB interrupts
for which it is not ready which results in processing them
before init_firmware during driver probe

Fix:
Two steps solution
1. Make driver ready to process the interrupt before interupts
   handlers is registered.
2. Stop driver processing iocb interrupts if not generated as per
   firmware protocol i.e R2H bit set
Signed-off-by: Tej Parkash <tej.parkash@qlogic.com>
Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

drivers/scsi/qla4xxx/ql4_isr.c

@@ -1022,7 +1022,8 @@ void qla4_82xx_interrupt_service_routine(struct scsi_qla_host *ha,
     uint32_t intr_status)
 {
 	/* Process response queue interrupt. */
-	if (intr_status & HSRX_RISC_IOCB_INT)
+	if ((intr_status & HSRX_RISC_IOCB_INT) &&
+	    test_bit(AF_INIT_DONE, &ha->flags))
 		qla4xxx_process_response_queue(ha);
 
 	/* Process mailbox/asynch event interrupt.*/
@@ -1399,6 +1400,7 @@ qla4_8xxx_msix_rsp_q(int irq, void *dev_id)
 {
 	struct scsi_qla_host *ha = dev_id;
 	unsigned long flags;
+	int intr_status;
 	uint32_t ival = 0;
 
 	spin_lock_irqsave(&ha->hardware_lock, flags);
@@ -1412,8 +1414,15 @@ qla4_8xxx_msix_rsp_q(int irq, void *dev_id)
 		qla4xxx_process_response_queue(ha);
 		writel(0, &ha->qla4_83xx_reg->iocb_int_mask);
 	} else {
+		intr_status = readl(&ha->qla4_82xx_reg->host_status);
+		if (intr_status & HSRX_RISC_IOCB_INT) {
 			qla4xxx_process_response_queue(ha);
 			writel(0, &ha->qla4_82xx_reg->host_int);
+		} else {
+			ql4_printk(KERN_INFO, ha, "%s: spurious iocb interrupt...\n",
+				   __func__);
+			goto exit_msix_rsp_q;
+		}
 	}
 	ha->isr_count++;
 exit_msix_rsp_q:

drivers/scsi/qla4xxx/ql4_mbx.c

@@ -648,9 +648,6 @@ int qla4xxx_initialize_fw_cb(struct scsi_qla_host * ha)
 		goto exit_init_fw_cb;
 	}
 
-	/* Initialize request and response queues. */
-	qla4xxx_init_rings(ha);
-
 	/* Fill in the request and response queue information. */
 	init_fw_cb->rqq_consumer_idx = cpu_to_le16(ha->request_out);
 	init_fw_cb->compq_producer_idx = cpu_to_le16(ha->response_in);

drivers/scsi/qla4xxx/ql4_nx.c

@@ -3190,6 +3190,10 @@ int qla4_8xxx_load_risc(struct scsi_qla_host *ha)
 
 	retval = qla4_8xxx_device_state_handler(ha);
 
+	/* Initialize request and response queues. */
+	if (retval == QLA_SUCCESS)
+		qla4xxx_init_rings(ha);
+
 	if (retval == QLA_SUCCESS && !test_bit(AF_IRQ_ATTACHED, &ha->flags))
 		retval = qla4xxx_request_irqs(ha);