[PATCH 4/4] vdpa/octeon_ep: add interrupt handler for virtio crypto device

[Shijith Thotton]

Introduced an interrupt handler for the virtio crypto device, as its
queue usage differs from that of network devices. While virtio network
device receives packets only on even-indexed queues, virtio crypto
device utilize all available queues for processing data.

Signed-off-by: Shijith Thotton <sthot...@marvell.com>
---
 drivers/vdpa/octeon_ep/octep_vdpa_main.c | 51 +++++++++++++++++++++++-
 1 file changed, 49 insertions(+), 2 deletions(-)

diff --git a/drivers/vdpa/octeon_ep/octep_vdpa_main.c 
b/drivers/vdpa/octeon_ep/octep_vdpa_main.c
index 6ead42d76415..1b65cb697fa5 100644
--- a/drivers/vdpa/octeon_ep/octep_vdpa_main.c
+++ b/drivers/vdpa/octeon_ep/octep_vdpa_main.c
@@ -44,7 +44,35 @@ static struct octep_hw *vdpa_to_octep_hw(struct vdpa_device 
*vdpa_dev)
        return oct_vdpa->oct_hw;
 }
 
-static irqreturn_t octep_vdpa_intr_handler(int irq, void *data)
+static irqreturn_t octep_vdpa_crypto_irq_handler(int irq, void *data)
+{
+       struct octep_hw *oct_hw = data;
+       int i;
+
+       /* Each device interrupt (nb_irqs) maps to specific receive rings
+        * (nr_vring) in a round-robin fashion.
+        *
+        * For example, if nb_irqs = 8 and nr_vring = 64:
+        * 0 -> 0, 8, 16, 24, 32, 40, 48, 56;
+        * 1 -> 1, 9, 17, 25, 33, 41, 49, 57;
+        * ...
+        * 7 -> 7, 15, 23, 31, 39, 47, 55, 63;
+        */
+       for (i = irq - oct_hw->irqs[0]; i < oct_hw->nr_vring; i += 
oct_hw->nb_irqs) {
+               if (ioread32(oct_hw->vqs[i].cb_notify_addr)) {
+                       /* Acknowledge the per ring notification to the device 
*/
+                       iowrite32(0, oct_hw->vqs[i].cb_notify_addr);
+
+                       if (likely(oct_hw->vqs[i].cb.callback))
+                               
oct_hw->vqs[i].cb.callback(oct_hw->vqs[i].cb.private);
+                       break;
+               }
+       }
+
+       return IRQ_HANDLED;
+}
+
+static irqreturn_t octep_vdpa_net_irq_handler(int irq, void *data)
 {
        struct octep_hw *oct_hw = data;
        int i, ring_start, ring_stride;
@@ -85,6 +113,18 @@ static irqreturn_t octep_vdpa_intr_handler(int irq, void 
*data)
        return IRQ_HANDLED;
 }
 
+static irqreturn_t (*octep_vdpa_get_irq_handler(u32 dev_id))(int, void *)
+{
+       switch (dev_id) {
+       case VIRTIO_ID_NET:
+               return octep_vdpa_net_irq_handler;
+       case VIRTIO_ID_CRYPTO:
+               return octep_vdpa_crypto_irq_handler;
+       default:
+               return NULL;
+       }
+}
+
 static void octep_free_irqs(struct octep_hw *oct_hw)
 {
        struct pci_dev *pdev = oct_hw->pdev;
@@ -103,6 +143,7 @@ static void octep_free_irqs(struct octep_hw *oct_hw)
 
 static int octep_request_irqs(struct octep_hw *oct_hw)
 {
+       irqreturn_t (*irq_handler)(int irq, void *data);
        struct pci_dev *pdev = oct_hw->pdev;
        int ret, irq, idx;
 
@@ -119,10 +160,16 @@ static int octep_request_irqs(struct octep_hw *oct_hw)
        }
 
        memset(oct_hw->irqs, -1, sizeof(oct_hw->irqs));
+       irq_handler = octep_vdpa_get_irq_handler(oct_hw->dev_id);
+       if (!irq_handler) {
+               dev_err(&pdev->dev, "Invalid device id %d\n", oct_hw->dev_id);
+               ret = -EINVAL;
+               goto free_irqs;
+       }
 
        for (idx = 0; idx < oct_hw->nb_irqs; idx++) {
                irq = pci_irq_vector(pdev, idx);
-               ret = devm_request_irq(&pdev->dev, irq, 
octep_vdpa_intr_handler, 0,
+               ret = devm_request_irq(&pdev->dev, irq, irq_handler, 0,
                                       dev_name(&pdev->dev), oct_hw);
                if (ret) {
                        dev_err(&pdev->dev, "Failed to register interrupt 
handler\n");
-- 
2.25.1