Subject: [PATCH 5/7] vDPA/ifcvf: irq request helpers for both shared and per_vq irq

From: Zhu Lingshan <[email-masked]>
Date: Mon, 10 Jan 2022 13:18:49 +0800

This commit implements new irq request helpers:
ifcvf_request_shared_vq_irq() for a shared irq, in this case,
all virtqueues would share one irq/vector. This can help the
device work on some platforms that can not provide enough
MSIX vectors

ifcvf_request_per_vq_irq() for per vq irqs, in this case,
every virtqueue has its own irq/vector

ifcvf_request_vq_irq() calls either of the above two, depends on
the number of allocated vectors.

Signed-off-by: Zhu Lingshan <[email-masked]>
---
 drivers/vdpa/ifcvf/ifcvf_base.c |  9 -----
 drivers/vdpa/ifcvf/ifcvf_main.c | 66 +++++++++++++++++++++++++++++++++
 2 files changed, 66 insertions(+), 9 deletions(-)

diff --git a/drivers/vdpa/ifcvf/ifcvf_base.c b/drivers/vdpa/ifcvf/ifcvf_base.c
index 696a41560eaa..fc496d10cf8d 100644
--- a/drivers/vdpa/ifcvf/ifcvf_base.c
+++ b/drivers/vdpa/ifcvf/ifcvf_base.c
@@ -349,15 +349,6 @@ static int ifcvf_hw_enable(struct ifcvf_hw *hw)
 		ifc_iowrite64_twopart(hw->vring[i].used, &cfg->queue_used_lo,
 				     &cfg->queue_used_hi);
 		ifc_iowrite16(hw->vring[i].size, &cfg->queue_size);
-		ifc_iowrite16(i + IFCVF_MSI_QUEUE_OFF, &cfg->queue_msix_vector);
-
-		if (ifc_ioread16(&cfg->queue_msix_vector) ==
-		    VIRTIO_MSI_NO_VECTOR) {
-			IFCVF_ERR(ifcvf->pdev,
-				  "No msix vector for queue %u\n", i);
-			return -EINVAL;
-		}
-
 		ifcvf_set_vq_state(hw, i, hw->vring[i].last_avail_idx);
 		ifc_iowrite16(1, &cfg->queue_enable);
 	}
diff --git a/drivers/vdpa/ifcvf/ifcvf_main.c b/drivers/vdpa/ifcvf/ifcvf_main.c
index 19e1d1cd71a3..ce2fbc429fbe 100644
--- a/drivers/vdpa/ifcvf/ifcvf_main.c
+++ b/drivers/vdpa/ifcvf/ifcvf_main.c
@@ -97,6 +97,72 @@ static int ifcvf_alloc_vectors(struct ifcvf_adapter *adapter)
 	return ret;
 }
 
+static int ifcvf_request_per_vq_irq(struct ifcvf_adapter *adapter)
+{
+	struct pci_dev *pdev = adapter->pdev;
+	struct ifcvf_hw *vf = &adapter->vf;
+	int i, vector, ret, irq;
+
+	for (i = 0; i < vf->nr_vring; i++) {
+		snprintf(vf->vring[i].msix_name, 256, "ifcvf[%s]-%d\n", pci_name(pdev), i);
+		vector = i;
+		irq = pci_irq_vector(pdev, vector);
+		ret = devm_request_irq(&pdev->dev, irq,
+				       ifcvf_intr_handler, 0,
+				       vf->vring[i].msix_name,
+				       &vf->vring[i]);
+		if (ret) {
+			IFCVF_ERR(pdev, "Failed to request irq for vq %d\n", i);
+			ifcvf_free_irq(adapter, i);
+		} else {
+			vf->vring[i].irq = irq;
+			ifcvf_set_vq_vector(vf, i, vector);
+		}
+	}
+
+	return 0;
+}
+
+static int ifcvf_request_shared_vq_irq(struct ifcvf_adapter *adapter)
+{
+	struct pci_dev *pdev = adapter->pdev;
+	struct ifcvf_hw *vf = &adapter->vf;
+	int i, vector, ret, irq;
+
+	vector = 0;
+	irq = pci_irq_vector(pdev, vector);
+	ret = devm_request_irq(&pdev->dev, irq,
+			       ifcvf_shared_intr_handler, 0,
+			       "ifcvf_shared_irq",
+			       vf);
+	if (ret) {
+		IFCVF_ERR(pdev, "Failed to request shared irq for vf\n");
+
+		return ret;
+	}
+
+	for (i = 0; i < vf->nr_vring; i++) {
+		vf->vring[i].irq = irq;
+		ifcvf_set_vq_vector(vf, i, vector);
+	}
+
+	return 0;
+
+}
+
+static int ifcvf_request_vq_irq(struct ifcvf_adapter *adapter, u8 vector_per_vq)
+{
+	int ret;
+
+	if (vector_per_vq)
+		ret = ifcvf_request_per_vq_irq(adapter);
+	else
+		ret = ifcvf_request_shared_vq_irq(adapter);
+
+	return ret;
+}
+
+
 static int ifcvf_request_irq(struct ifcvf_adapter *adapter)
 {
 	struct pci_dev *pdev = adapter->pdev;
-- 
2.27.0