diff --git a/drivers/of/of_pci_irq.c b/drivers/of/of_pci_irq.c
index 3a05568f65df..d8194c0ca2d4 100644
--- a/drivers/of/of_pci_irq.c
+++ b/drivers/of/of_pci_irq.c
@@ -28,6 +28,7 @@ int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq
    dn = pci_device_to_OF_node(pdev);
    if (dn) {
        rc = of_irq_parse_one(dn, 0, out_irq);
+dev_dbg(&pdev->dev, "direct parse found irq %d:%d\n", out_irq->args[0], out_irq->args[1]);
        if (!rc)
            return rc;
    }
@@ -39,6 +40,7 @@ int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq
    rc = pci_read_config_byte(pdev, PCI_INTERRUPT_PIN, &pin);
    if (rc != 0)
        goto err;
+dev_dbg(&pdev->dev, "parse pin %d\n", pin);
    /* No pin, exit with no error message. */
    if (pin == 0)
        return -ENODEV;
@@ -62,6 +64,8 @@ int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq
            ppnode = pci_device_to_OF_node(ppdev);
        }

+dev_dbg(&ppdev->dev, "node %p pin %d\n", ppnode, pin);
+
        /* Ok, we have found a parent with a device-node, hand over to
         * the OF parsing code.
         * We build a unit address from the linux device to be used for
@@ -88,7 +92,9 @@ int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq
    out_irq->args[0] = pin;
    laddr[0] = cpu_to_be32((pdev->bus->number << 16) | (pdev->devfn << 8));
    laddr[1] = laddr[2] = cpu_to_be32(0);
+dev_dbg(&ppdev->dev, "parse node %p pin %d\n", ppnode, pin);
    rc = of_irq_parse_raw(laddr, out_irq);
+dev_dbg(&ppdev->dev, "parse node %p irq %d:%d\n", ppnode, out_irq->args[0], out_irq->args[1]);
    if (rc)
        goto err;
    return 0;
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 47f364d87fd1..c5b67189df46 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -3117,10 +3117,12 @@ u8 pci_common_swizzle(struct pci_dev *dev, u8 *pinp)
    u8 pin = *pinp;

    while (!pci_is_root_bus(dev->bus)) {
+dev_dbg(&dev->dev, "swizzle pin %d\n", pin);
        pin = pci_swizzle_interrupt_pin(dev, pin);
        dev = dev->bus->self;
    }
    *pinp = pin;
+dev_dbg(&dev->dev, "swizzle found slot %d pin %d\n", PCI_SLOT(dev->devfn), pin);
    return PCI_SLOT(dev->devfn);
 }
 EXPORT_SYMBOL_GPL(pci_common_swizzle);