scsi: qla2xxx: Reinstate module parameter ql2xenablemsix

[mkp: fixed whitespace]
Signed-off-by: Himanshu Madhani <himanshu.madhani@cavium.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

drivers/scsi/qla2xxx/qla_gbl.h

@@ -145,6 +145,7 @@ extern int ql2xmvasynctoatio;
 extern int ql2xuctrlirq;
 extern int ql2xnvmeenable;
 extern int ql2xautodetectsfp;
+extern int ql2xenablemsix;
 
 extern int qla2x00_loop_reset(scsi_qla_host_t *);
 extern void qla2x00_abort_all_cmds(scsi_qla_host_t *, int);

drivers/scsi/qla2xxx/qla_isr.c

@@ -3486,11 +3486,14 @@ qla2x00_request_irqs(struct qla_hw_data *ha, struct rsp_que *rsp)
 	scsi_qla_host_t *vha = pci_get_drvdata(ha->pdev);
 
 	/* If possible, enable MSI-X. */
-	if (!IS_QLA2432(ha) && !IS_QLA2532(ha) && !IS_QLA8432(ha) &&
-	    !IS_CNA_CAPABLE(ha) && !IS_QLA2031(ha) && !IS_QLAFX00(ha) &&
-	    !IS_QLA27XX(ha))
+	if (ql2xenablemsix == 0 || (!IS_QLA2432(ha) && !IS_QLA2532(ha) &&
+	    !IS_QLA8432(ha) && !IS_CNA_CAPABLE(ha) && !IS_QLA2031(ha) &&
+	    !IS_QLAFX00(ha) && !IS_QLA27XX(ha)))
 		goto skip_msi;
 
+	if (ql2xenablemsix == 2)
+		goto skip_msix;
+
 	if (ha->pdev->subsystem_vendor == PCI_VENDOR_ID_HP &&
 		(ha->pdev->subsystem_device == 0x7040 ||
 		ha->pdev->subsystem_device == 0x7041 ||

drivers/scsi/qla2xxx/qla_os.c

@@ -268,6 +268,15 @@ MODULE_PARM_DESC(ql2xautodetectsfp,
 		 "Detect SFP range and set appropriate distance.\n"
 		 "1 (Default): Enable\n");
 
+int ql2xenablemsix = 1;
+module_param(ql2xenablemsix, int, 0444);
+MODULE_PARM_DESC(ql2xenablemsix,
+		 "Set to enable MSI or MSI-X interrupt mechanism.\n"
+		 " Default is 1, enable MSI-X interrupt mechanism.\n"
+		 " 0 -- enable traditional pin-based mechanism.\n"
+		 " 1 -- enable MSI-X interrupt mechanism.\n"
+		 " 2 -- enable MSI interrupt mechanism.\n");
+
 /*
  * SCSI host template entry points
  */