Re: [PATCH v2 1/2] PCI: dra7xx: Fix legacy INTD IRQ handling

From: Kishon Vijay Abraham I
Date: Thu Jan 04 2018 - 01:09:10 EST




On Friday 29 December 2017 05:11 PM, Vignesh R wrote:
> 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>

Acked-by: Kishon Vijay Abraham I <kishon@xxxxxx>
> ---
> drivers/pci/dwc/pci-dra7xx.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/pci/dwc/pci-dra7xx.c b/drivers/pci/dwc/pci-dra7xx.c
> index 58aed0896468..892f93910012 100644
> --- a/drivers/pci/dwc/pci-dra7xx.c
> +++ b/drivers/pci/dwc/pci-dra7xx.c
> @@ -226,6 +226,7 @@ static int dra7xx_pcie_intx_map(struct irq_domain *domain, unsigned int irq,
>
> 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)
> @@ -269,7 +270,7 @@ static irqreturn_t dra7xx_pcie_msi_irq_handler(int irq, void *arg)
> case INTC:
> case INTD:
> generic_handle_irq(irq_find_mapping(dra7xx->irq_domain,
> - ffs(reg)));
> + ffs(reg) - 1));
> break;
> }
>
>