+static irqreturn_t ntb_transport_isr(int irq, void *dev)
+{
+ struct ntb_transport_qp *qp = dev;
+
+ tasklet_schedule(&qp->rxc_db_work);
+
+ return IRQ_HANDLED;
+}
+
+static void ntb_transport_setup_qp_peer_msi(struct ntb_transport_ctx *nt,
+ unsigned int qp_num)
+{
+ struct ntb_transport_qp *qp = &nt->qp_vec[qp_num];
+ int spad = qp_num * 2 + nt->msi_spad_offset;
+
+ if (!nt->use_msi)
+ return;
+
+ if (spad >= ntb_spad_count(nt->ndev))
+ return;
+
+ qp->peer_msi_desc.addr_offset =
+ ntb_peer_spad_read(qp->ndev, PIDX, spad);
+ qp->peer_msi_desc.data =
+ ntb_peer_spad_read(qp->ndev, PIDX, spad + 1);
+
+ dev_dbg(&qp->ndev->pdev->dev, "QP%d Peer MSI addr=%x data=%x\n",
+ qp_num, qp->peer_msi_desc.addr_offset, qp->peer_msi_desc.data);
+
+ if (qp->peer_msi_desc.addr_offset) {
+ qp->use_msi = true;
+ dev_info(&qp->ndev->pdev->dev,
+ "Using MSI interrupts for QP%d\n", qp_num);
+ }
+}
+
+static void ntb_transport_setup_qp_msi(struct ntb_transport_ctx *nt,
+ unsigned int qp_num)
+{
+ struct ntb_transport_qp *qp = &nt->qp_vec[qp_num];
+ int spad = qp_num * 2 + nt->msi_spad_offset;
+ int rc;
+
+ if (!nt->use_msi)
+ return;
+
+ if (spad >= ntb_spad_count(nt->ndev)) {
+ dev_warn_once(&qp->ndev->pdev->dev,
+ "Not enough SPADS to use MSI interrupts\n");
+ return;
+ }
+
+ ntb_spad_write(qp->ndev, spad, 0);
+ ntb_spad_write(qp->ndev, spad + 1, 0);
+
+ if (!qp->msi_irq) {
+ qp->msi_irq = ntbm_msi_request_irq(qp->ndev, ntb_transport_isr,
+ KBUILD_MODNAME, qp,
+ &qp->msi_desc);
+ if (qp->msi_irq < 0) {
+ dev_warn(&qp->ndev->pdev->dev,
+ "Unable to allocate MSI interrupt for qp%d\n",
+ qp_num);
+ return;
+ }
+ }
+
+ rc = ntb_spad_write(qp->ndev, spad, qp->msi_desc.addr_offset);
+ if (rc)
+ goto err_free_interrupt;
+
+ rc = ntb_spad_write(qp->ndev, spad + 1, qp->msi_desc.data);
+ if (rc)
+ goto err_free_interrupt;
+
+ dev_dbg(&qp->ndev->pdev->dev, "QP%d MSI %d addr=%x data=%x\n",
+ qp_num, qp->msi_irq, qp->msi_desc.addr_offset,
+ qp->msi_desc.data);
+
+ return;
+
+err_free_interrupt:
+ devm_free_irq(&nt->ndev->dev, qp->msi_irq, qp);
+}
+
+static void ntb_transport_msi_peer_desc_changed(struct ntb_transport_ctx *nt)
+{
+ int i;
+
+ dev_dbg(&nt->ndev->pdev->dev, "Peer MSI descriptors changed");
+
+ for (i = 0; i < nt->qp_count; i++)
+ ntb_transport_setup_qp_peer_msi(nt, i);
+}
+
+static void ntb_transport_msi_desc_changed(void *data)
+{
+ struct ntb_transport_ctx *nt = data;
+ int i;
+
+ dev_dbg(&nt->ndev->pdev->dev, "MSI descriptors changed");
+
+ for (i = 0; i < nt->qp_count; i++)
+ ntb_transport_setup_qp_msi(nt, i);
+
+ ntb_peer_db_set(nt->ndev, nt->msi_db_mask);
+}
+