[SCSI] pm80xx: MSI-X implementation for using 64 interrupts

Implementation of interrupt handlers and tasklets to support
upto 64 interrupt for the device.

Signed-off-by: Sakthivel K <Sakthivel.SaravananKamalRaju@pmcs.com>
Signed-off-by: Anand Kumar S <AnandKumar.Santhanam@pmcs.com>
Acked-by: Jack Wang <jack_wang@usish.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

2 files changed, 113 insertions, 30 deletions

diff --git a/drivers/scsi/pm8001/pm8001_init.c b/drivers/scsi/pm8001/pm8001_init.c
index 19fbd03b4190..75270ee1a7f0 100644
--- a/drivers/scsi/pm8001/pm8001_init.c
+++ b/drivers/scsi/pm8001/pm8001_init.c
@@ -159,33 +159,71 @@ static void pm8001_free(struct pm8001_hba_info *pm8001_ha)
 }
 
 #ifdef PM8001_USE_TASKLET
+
+/**
+ * tasklet for 64 msi-x interrupt handler
+ * @opaque: the passed general host adapter struct
+ * Note: pm8001_tasklet is common for pm8001 & pm80xx
+ */
 static void pm8001_tasklet(unsigned long opaque)
 {
         struct pm8001_hba_info *pm8001_ha;
+        u32 vec;
         pm8001_ha = (struct pm8001_hba_info *)opaque;
         if (unlikely(!pm8001_ha))
                 BUG_ON(1);
-        PM8001_CHIP_DISP->isr(pm8001_ha, 0);
+        vec = pm8001_ha->int_vector;
+        PM8001_CHIP_DISP->isr(pm8001_ha, vec);
+}
+#endif
+
+static struct  pm8001_hba_info *outq_to_hba(u8 *outq)
+{
+        return container_of((outq - *outq), struct pm8001_hba_info, outq[0]);
 }
+
+/**
+ * pm8001_interrupt_handler_msix - main MSIX interrupt handler.
+ * It obtains the vector number and calls the equivalent bottom
+ * half or services directly.
+ * @opaque: the passed outbound queue/vector. Host structure is
+ * retrieved from the same.
+ */
+static irqreturn_t pm8001_interrupt_handler_msix(int irq, void *opaque)
+{
+        struct pm8001_hba_info *pm8001_ha = outq_to_hba(opaque);
+        u8 outq = *(u8 *)opaque;
+        irqreturn_t ret = IRQ_HANDLED;
+        if (unlikely(!pm8001_ha))
+                return IRQ_NONE;
+        if (!PM8001_CHIP_DISP->is_our_interupt(pm8001_ha))
+                return IRQ_NONE;
+        pm8001_ha->int_vector = outq;
+#ifdef PM8001_USE_TASKLET
+        tasklet_schedule(&pm8001_ha->tasklet);
+#else
+        ret = PM8001_CHIP_DISP->isr(pm8001_ha, outq);
 #endif
+        return ret;
+}
 
+/**
+ * pm8001_interrupt_handler_intx - main INTx interrupt handler.
+ * @dev_id: sas_ha structure. The HBA is retrieved from sas_has structure.
+ */
 
- /**
-  * pm8001_interrupt - when HBA originate a interrupt,we should invoke this
-  * dispatcher to handle each case.
-  * @irq: irq number.
-  * @opaque: the passed general host adapter struct
-  */
-static irqreturn_t pm8001_interrupt(int irq, void *opaque)
+static irqreturn_t pm8001_interrupt_handler_intx(int irq, void *dev_id)
 {
         struct pm8001_hba_info *pm8001_ha;
         irqreturn_t ret = IRQ_HANDLED;
-        struct sas_ha_struct *sha = opaque;
+        struct sas_ha_struct *sha = dev_id;
         pm8001_ha = sha->lldd_ha;
         if (unlikely(!pm8001_ha))
                 return IRQ_NONE;
         if (!PM8001_CHIP_DISP->is_our_interupt(pm8001_ha))
                 return IRQ_NONE;
+
+        pm8001_ha->int_vector = 0;
 #ifdef PM8001_USE_TASKLET
         tasklet_schedule(&pm8001_ha->tasklet);
 #else
@@ -427,8 +465,12 @@ static struct pm8001_hba_info *pm8001_pci_alloc(struct pci_dev *pdev,
                 pm8001_ha->iomb_size = IOMB_SIZE_SPC;
 
 #ifdef PM8001_USE_TASKLET
+        /**
+        * default tasklet for non msi-x interrupt handler/first msi-x
+        * interrupt handler
+        **/
         tasklet_init(&pm8001_ha->tasklet, pm8001_tasklet,
-                (unsigned long)pm8001_ha);
+                        (unsigned long)pm8001_ha);
 #endif
         pm8001_ioremap(pm8001_ha);
         if (!pm8001_alloc(pm8001_ha, ent))
@@ -591,31 +633,50 @@ static void pm8001_init_sas_add(struct pm8001_hba_info *pm8001_ha)
  * @chip_info: our ha struct.
  * @irq_handler: irq_handler
  */
-static u32 pm8001_setup_msix(struct pm8001_hba_info *pm8001_ha,
-        irq_handler_t irq_handler)
+static u32 pm8001_setup_msix(struct pm8001_hba_info *pm8001_ha)
 {
         u32 i = 0, j = 0;
-        u32 number_of_intr = 1;
+        u32 number_of_intr;
         int flag = 0;
         u32 max_entry;
         int rc;
+        static char intr_drvname[PM8001_MAX_MSIX_VEC][sizeof(DRV_NAME)+3];
+
+        /* SPCv controllers supports 64 msi-x */
+        if (pm8001_ha->chip_id == chip_8001) {
+                number_of_intr = 1;
+                flag |= IRQF_DISABLED;
+        } else {
+                number_of_intr = PM8001_MAX_MSIX_VEC;
+                flag &= ~IRQF_SHARED;
+                flag |= IRQF_DISABLED;
+        }
+
         max_entry = sizeof(pm8001_ha->msix_entries) /
                 sizeof(pm8001_ha->msix_entries[0]);
-        flag |= IRQF_DISABLED;
         for (i = 0; i < max_entry ; i++)
                 pm8001_ha->msix_entries[i].entry = i;
         rc = pci_enable_msix(pm8001_ha->pdev, pm8001_ha->msix_entries,
                 number_of_intr);
         pm8001_ha->number_of_intr = number_of_intr;
         if (!rc) {
+                PM8001_INIT_DBG(pm8001_ha, pm8001_printk(
+                        "pci_enable_msix request ret:%d no of intr %d\n",
+                                        rc, pm8001_ha->number_of_intr));
+
+                for (i = 0; i < number_of_intr; i++)
+                        pm8001_ha->outq[i] = i;
+
                 for (i = 0; i < number_of_intr; i++) {
+                        snprintf(intr_drvname[i], sizeof(intr_drvname[0]),
+                                        DRV_NAME"%d", i);
                         if (request_irq(pm8001_ha->msix_entries[i].vector,
-                                irq_handler, flag, DRV_NAME,
-                                SHOST_TO_SAS_HA(pm8001_ha->shost))) {
+                                pm8001_interrupt_handler_msix, flag,
+                                intr_drvname[i], &pm8001_ha->outq[i])) {
                                 for (j = 0; j < i; j++)
                                         free_irq(
                                         pm8001_ha->msix_entries[j].vector,
-                                        SHOST_TO_SAS_HA(pm8001_ha->shost));
+                                        &pm8001_ha->outq[j]);
                                 pci_disable_msix(pm8001_ha->pdev);
                                 break;
                         }
@@ -632,22 +693,24 @@ static u32 pm8001_setup_msix(struct pm8001_hba_info *pm8001_ha,
 static u32 pm8001_request_irq(struct pm8001_hba_info *pm8001_ha)
 {
         struct pci_dev *pdev;
-        irq_handler_t irq_handler = pm8001_interrupt;
         int rc;
 
         pdev = pm8001_ha->pdev;
 
 #ifdef PM8001_USE_MSIX
         if (pci_find_capability(pdev, PCI_CAP_ID_MSIX))
-                return pm8001_setup_msix(pm8001_ha, irq_handler);
-        else
+                return pm8001_setup_msix(pm8001_ha);
+        else {
+                PM8001_INIT_DBG(pm8001_ha,
+                        pm8001_printk("MSIX not supported!!!\n"));
                 goto intx;
+        }
 #endif
 
 intx:
         /* initialize the INT-X interrupt */
-        rc = request_irq(pdev->irq, irq_handler, IRQF_SHARED, DRV_NAME,
-                SHOST_TO_SAS_HA(pm8001_ha->shost));
+        rc = request_irq(pdev->irq, pm8001_interrupt_handler_intx, IRQF_SHARED,
+                DRV_NAME, SHOST_TO_SAS_HA(pm8001_ha->shost));
         return rc;
 }
 
@@ -665,6 +728,7 @@ static int pm8001_pci_probe(struct pci_dev *pdev,
 {
         unsigned int rc;
         u32     pci_reg;
+        u8      i = 0;
         struct pm8001_hba_info *pm8001_ha;
         struct Scsi_Host *shost = NULL;
         const struct pm8001_chip_info *chip;
@@ -729,6 +793,11 @@ static int pm8001_pci_probe(struct pci_dev *pdev,
                 goto err_out_shost;
 
         PM8001_CHIP_DISP->interrupt_enable(pm8001_ha, 0);
+        if (pm8001_ha->chip_id != chip_8001) {
+                for (i = 1; i < pm8001_ha->number_of_intr; i++)
+                        PM8001_CHIP_DISP->interrupt_enable(pm8001_ha, i);
+        }
+
         pm8001_init_sas_add(pm8001_ha);
         pm8001_post_sas_ha_init(shost, chip);
         rc = sas_register_ha(SHOST_TO_SAS_HA(shost));
@@ -764,14 +833,15 @@ static void pm8001_pci_remove(struct pci_dev *pdev)
         sas_remove_host(pm8001_ha->shost);
         list_del(&pm8001_ha->list);
         scsi_remove_host(pm8001_ha->shost);
-        PM8001_CHIP_DISP->interrupt_disable(pm8001_ha, 0);
+        PM8001_CHIP_DISP->interrupt_disable(pm8001_ha, 0xFF);
         PM8001_CHIP_DISP->chip_soft_rst(pm8001_ha, 0x252acbcd);
 
 #ifdef PM8001_USE_MSIX
         for (i = 0; i < pm8001_ha->number_of_intr; i++)
                 synchronize_irq(pm8001_ha->msix_entries[i].vector);
         for (i = 0; i < pm8001_ha->number_of_intr; i++)
-                free_irq(pm8001_ha->msix_entries[i].vector, sha);
+                free_irq(pm8001_ha->msix_entries[i].vector,
+                                &pm8001_ha->outq[i]);
         pci_disable_msix(pdev);
 #else
         free_irq(pm8001_ha->irq, sha);
@@ -808,13 +878,14 @@ static int pm8001_pci_suspend(struct pci_dev *pdev, pm_message_t state)
                 printk(KERN_ERR " PCI PM not supported\n");
                 return -ENODEV;
         }
-        PM8001_CHIP_DISP->interrupt_disable(pm8001_ha, 0);
+        PM8001_CHIP_DISP->interrupt_disable(pm8001_ha, 0xFF);
         PM8001_CHIP_DISP->chip_soft_rst(pm8001_ha, 0x252acbcd);
 #ifdef PM8001_USE_MSIX
         for (i = 0; i < pm8001_ha->number_of_intr; i++)
                 synchronize_irq(pm8001_ha->msix_entries[i].vector);
         for (i = 0; i < pm8001_ha->number_of_intr; i++)
-                free_irq(pm8001_ha->msix_entries[i].vector, sha);
+                free_irq(pm8001_ha->msix_entries[i].vector,
+                                &pm8001_ha->outq[i]);
         pci_disable_msix(pdev);
 #else
         free_irq(pm8001_ha->irq, sha);
@@ -843,6 +914,7 @@ static int pm8001_pci_resume(struct pci_dev *pdev)
         struct sas_ha_struct *sha = pci_get_drvdata(pdev);
         struct pm8001_hba_info *pm8001_ha;
         int rc;
+        u8 i = 0;
         u32 device_state;
         pm8001_ha = sha->lldd_ha;
         device_state = pdev->current_state;
@@ -869,15 +941,24 @@ static int pm8001_pci_resume(struct pci_dev *pdev)
         rc = PM8001_CHIP_DISP->chip_init(pm8001_ha);
         if (rc)
                 goto err_out_disable;
-        PM8001_CHIP_DISP->interrupt_disable(pm8001_ha, 0);
+
+        /* disable all the interrupt bits */
+        PM8001_CHIP_DISP->interrupt_disable(pm8001_ha, 0xFF);
+
         rc = pm8001_request_irq(pm8001_ha);
         if (rc)
                 goto err_out_disable;
-        #ifdef PM8001_USE_TASKLET
+#ifdef PM8001_USE_TASKLET
+        /* default tasklet for non msi-x interrupt handler/first msi-x
+        * interrupt handler */
         tasklet_init(&pm8001_ha->tasklet, pm8001_tasklet,
-                    (unsigned long)pm8001_ha);
-        #endif
+                        (unsigned long)pm8001_ha);
+#endif
         PM8001_CHIP_DISP->interrupt_enable(pm8001_ha, 0);
+        if (pm8001_ha->chip_id != chip_8001) {
+                for (i = 1; i < pm8001_ha->number_of_intr; i++)
+                        PM8001_CHIP_DISP->interrupt_enable(pm8001_ha, i);
+        }
         scsi_unblock_requests(pm8001_ha->shost);
         return 0;
 
diff --git a/drivers/scsi/pm8001/pm8001_sas.h b/drivers/scsi/pm8001/pm8001_sas.h
index e0faa9597c26..8e281c8deff2 100644
--- a/drivers/scsi/pm8001/pm8001_sas.h
+++ b/drivers/scsi/pm8001/pm8001_sas.h
@@ -453,7 +453,9 @@ struct pm8001_hba_info {
 #endif
         u32                     logging_level;
         u32                     fw_status;
+        u32                     int_vector;
         const struct firmware   *fw_image;
+        u8                      outq[PM8001_MAX_MSIX_VEC];
 };
 
 struct pm8001_work {