[SCSI] lpfc 8.2.5 : Add MSI-X single message support

Signed-off-by: James Smart <james.smart@emulex.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

3 files changed, 91 insertions, 22 deletions

diff --git a/drivers/scsi/lpfc/lpfc.h b/drivers/scsi/lpfc/lpfc.h
index cbe07d79bd12..10f983b479c6 100644
--- a/drivers/scsi/lpfc/lpfc.h
+++ b/drivers/scsi/lpfc/lpfc.h
@@ -392,6 +392,13 @@ enum hba_temp_state {
         HBA_OVER_TEMP
 };
 
+enum intr_type_t {
+        NONE = 0,
+        INTx,
+        MSI,
+        MSIX,
+};
+
 struct lpfc_hba {
         struct lpfc_sli sli;
         uint32_t sli_rev;               /* SLI2 or SLI3 */
@@ -555,7 +562,8 @@ struct lpfc_hba {
         mempool_t *nlp_mem_pool;
 
         struct fc_host_statistics link_stats;
-        uint8_t using_msi;
+        enum intr_type_t intr_type;
+        struct msix_entry msix_entries[1];
 
         struct list_head port_list;
         struct lpfc_vport *pport;       /* physical lpfc_vport pointer */
diff --git a/drivers/scsi/lpfc/lpfc_attr.c b/drivers/scsi/lpfc/lpfc_attr.c
index fc48e40c4d29..b12a841703ca 100644
--- a/drivers/scsi/lpfc/lpfc_attr.c
+++ b/drivers/scsi/lpfc/lpfc_attr.c
@@ -1592,9 +1592,11 @@ LPFC_ATTR_RW(poll_tmo, 10, 1, 255,
 #               support this feature
 #       0  = MSI disabled (default)
 #       1  = MSI enabled
-# Value range is [0,1]. Default value is 0.
+#       2  = MSI-X enabled
+# Value range is [0,2]. Default value is 0.
 */
-LPFC_ATTR_R(use_msi, 0, 0, 1, "Use Message Signaled Interrupts, if possible");
+LPFC_ATTR_R(use_msi, 0, 0, 2, "Use Message Signaled Interrupts (1) or "
+            "MSI-X (2), if possible");
 
 /*
 # lpfc_enable_hba_reset: Allow or prevent HBA resets to the hardware.
diff --git a/drivers/scsi/lpfc/lpfc_init.c b/drivers/scsi/lpfc/lpfc_init.c
index 99141545c25e..a087524acf41 100644
--- a/drivers/scsi/lpfc/lpfc_init.c
+++ b/drivers/scsi/lpfc/lpfc_init.c
@@ -1924,6 +1924,42 @@ void lpfc_host_attrib_init(struct Scsi_Host *shost)
         spin_unlock_irq(shost->host_lock);
 }
 
+static int
+lpfc_enable_msix(struct lpfc_hba *phba)
+{
+        int error;
+
+        phba->msix_entries[0].entry = 0;
+        phba->msix_entries[0].vector = 0;
+
+        error = pci_enable_msix(phba->pcidev, phba->msix_entries,
+                                ARRAY_SIZE(phba->msix_entries));
+        if (error) {
+                lpfc_printf_log(phba, KERN_INFO, LOG_INIT,
+                                "0420 Enable MSI-X failed (%d), continuing "
+                                "with MSI\n", error);
+                pci_disable_msix(phba->pcidev);
+                return error;
+        }
+
+        error = request_irq(phba->msix_entries[0].vector, lpfc_intr_handler, 0,
+                            LPFC_DRIVER_NAME, phba);
+        if (error) {
+                lpfc_printf_log(phba, KERN_ERR, LOG_INIT,
+                                "0421 MSI-X request_irq failed (%d), "
+                                "continuing with MSI\n", error);
+                pci_disable_msix(phba->pcidev);
+        }
+        return error;
+}
+
+static void
+lpfc_disable_msix(struct lpfc_hba *phba)
+{
+        free_irq(phba->msix_entries[0].vector, phba);
+        pci_disable_msix(phba->pcidev);
+}
+
 static int __devinit
 lpfc_pci_probe_one(struct pci_dev *pdev, const struct pci_device_id *pid)
 {
@@ -2125,24 +2161,36 @@ lpfc_pci_probe_one(struct pci_dev *pdev, const struct pci_device_id *pid)
         lpfc_debugfs_initialize(vport);
 
         pci_set_drvdata(pdev, shost);
+        phba->intr_type = NONE;
 
-        if (phba->cfg_use_msi) {
+        if (phba->cfg_use_msi == 2) {
+                error = lpfc_enable_msix(phba);
+                if (!error)
+                        phba->intr_type = MSIX;
+        }
+
+        /* Fallback to MSI if MSI-X initialization failed */
+        if (phba->cfg_use_msi >= 1 && phba->intr_type == NONE) {
                 retval = pci_enable_msi(phba->pcidev);
                 if (!retval)
-                        phba->using_msi = 1;
+                        phba->intr_type = MSI;
                 else
                         lpfc_printf_log(phba, KERN_INFO, LOG_INIT,
                                         "0452 Enable MSI failed, continuing "
                                         "with IRQ\n");
         }
 
-        retval = request_irq(phba->pcidev->irq, lpfc_intr_handler, IRQF_SHARED,
-                            LPFC_DRIVER_NAME, phba);
-        if (retval) {
-                lpfc_printf_log(phba, KERN_ERR, LOG_INIT,
-                        "0451 Enable interrupt handler failed\n");
-                error = retval;
-                goto out_disable_msi;
+        /* MSI-X is the only case the doesn't need to call request_irq */
+        if (phba->intr_type != MSIX) {
+                retval = request_irq(phba->pcidev->irq, lpfc_intr_handler,
+                                     IRQF_SHARED, LPFC_DRIVER_NAME, phba);
+                if (retval) {
+                        lpfc_printf_log(phba, KERN_ERR, LOG_INIT, "0451 Enable "
+                                        "interrupt handler failed\n");
+                        error = retval;
+                        goto out_disable_msi;
+                } else if (phba->intr_type != MSI)
+                        phba->intr_type = INTx;
         }
 
         phba->MBslimaddr = phba->slim_memmap_p;
@@ -2187,9 +2235,14 @@ out_remove_device:
 out_free_irq:
         lpfc_stop_phba_timers(phba);
         phba->pport->work_port_events = 0;
-        free_irq(phba->pcidev->irq, phba);
+
+        if (phba->intr_type == MSIX)
+                lpfc_disable_msix(phba);
+        else
+                free_irq(phba->pcidev->irq, phba);
+
 out_disable_msi:
-        if (phba->using_msi)
+        if (phba->intr_type == MSI)
                 pci_disable_msi(phba->pcidev);
         destroy_port(vport);
 out_kthread_stop:
@@ -2262,10 +2315,13 @@ lpfc_pci_remove_one(struct pci_dev *pdev)
 
         lpfc_debugfs_terminate(vport);
 
-        /* Release the irq reservation */
-        free_irq(phba->pcidev->irq, phba);
-        if (phba->using_msi)
-                pci_disable_msi(phba->pcidev);
+        if (phba->intr_type == MSIX)
+                lpfc_disable_msix(phba);
+        else {
+                free_irq(phba->pcidev->irq, phba);
+                if (phba->intr_type == MSI)
+                        pci_disable_msi(phba->pcidev);
+        }
 
         pci_set_drvdata(pdev, NULL);
         scsi_host_put(shost);
@@ -2324,10 +2380,13 @@ static pci_ers_result_t lpfc_io_error_detected(struct pci_dev *pdev,
         pring = &psli->ring[psli->fcp_ring];
         lpfc_sli_abort_iocb_ring(phba, pring);
 
-        /* Release the irq reservation */
-        free_irq(phba->pcidev->irq, phba);
-        if (phba->using_msi)
-                pci_disable_msi(phba->pcidev);
+        if (phba->intr_type == MSIX)
+                lpfc_disable_msix(phba);
+        else {
+                free_irq(phba->pcidev->irq, phba);
+                if (phba->intr_type == MSI)
+                        pci_disable_msi(phba->pcidev);
+        }
 
         /* Request a slot reset. */
         return PCI_ERS_RESULT_NEED_RESET;