[PATCH 4.14 10/21] PCI: dra7xx: Fix legacy INTD IRQ handling

From: Greg Kroah-Hartman
Date: Fri Sep 13 2019 - 09:09:59 EST


From: Vignesh R <vigneshr@xxxxxx>

commit 524d59f6e30aab5b618da55e604c802ccd83e708 upstream.

Legacy INTD IRQ handling is broken on dra7xx due to fact that driver
uses hwirq in range of 1-4 for INTA, INTD whereas IRQ domain is of size
4 which is numbered 0-3. Therefore when INTD IRQ line is used with
pci-dra7xx driver following warning is seen:

WARNING: CPU: 0 PID: 1 at kernel/irq/irqdomain.c:342 irq_domain_associate+0x12c/0x1c4
error: hwirq 0x4 is too large for dummy

Fix this by using pci_irqd_intx_xlate() helper to translate the INTx 1-4
range into the 0-3 as done in other PCIe drivers.

Suggested-by: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
Reported-by: Chris Welch <Chris.Welch@xxxxxxxxxxxxxxxxxx>
Signed-off-by: Vignesh R <vigneshr@xxxxxx>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@xxxxxxx>
Acked-by: Kishon Vijay Abraham I <kishon@xxxxxx>
Signed-off-by: Mathieu Poirier <mathieu.poirier@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/pci/dwc/pci-dra7xx.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/pci/dwc/pci-dra7xx.c
+++ b/drivers/pci/dwc/pci-dra7xx.c
@@ -227,6 +227,7 @@ static int dra7xx_pcie_intx_map(struct i

static const struct irq_domain_ops intx_domain_ops = {
.map = dra7xx_pcie_intx_map,
+ .xlate = pci_irqd_intx_xlate,
};

static int dra7xx_pcie_init_irq_domain(struct pcie_port *pp)
@@ -270,7 +271,7 @@ static irqreturn_t dra7xx_pcie_msi_irq_h
case INTC:
case INTD:
generic_handle_irq(irq_find_mapping(dra7xx->irq_domain,
- ffs(reg)));
+ ffs(reg) - 1));
break;
}