Re: [PATCH v2 2/2] PCI: dra7xx: Iterate over INTx status bits

From: Kishon Vijay Abraham I
Date: Thu Jan 04 2018 - 01:09:50 EST




On Friday 29 December 2017 05:11 PM, Vignesh R wrote:
> It is possible that more than one legacy IRQ may be set at the same
> time, therefore iterate and handle all the pending INTx interrupts
> before clearing the status and exiting the IRQ handler. Otherwise, some
> interrupts would be lost.
>
> Signed-off-by: Vignesh R <vigneshr@xxxxxx>

Acked-by: Kishon Vijay Abraham I <kishon@xxxxxx>
> ---
> drivers/pci/dwc/pci-dra7xx.c | 10 +++++++---
> 1 file changed, 7 insertions(+), 3 deletions(-)
>
> diff --git a/drivers/pci/dwc/pci-dra7xx.c b/drivers/pci/dwc/pci-dra7xx.c
> index 892f93910012..48c6ae535847 100644
> --- a/drivers/pci/dwc/pci-dra7xx.c
> +++ b/drivers/pci/dwc/pci-dra7xx.c
> @@ -257,7 +257,8 @@ static irqreturn_t dra7xx_pcie_msi_irq_handler(int irq, void *arg)
> struct dra7xx_pcie *dra7xx = arg;
> struct dw_pcie *pci = dra7xx->pci;
> struct pcie_port *pp = &pci->pp;
> - u32 reg;
> + unsigned long reg;
> + u32 virq, bit;
>
> reg = dra7xx_pcie_readl(dra7xx, PCIECTRL_DRA7XX_CONF_IRQSTATUS_MSI);
>
> @@ -269,8 +270,11 @@ static irqreturn_t dra7xx_pcie_msi_irq_handler(int irq, void *arg)
> case INTB:
> case INTC:
> case INTD:
> - generic_handle_irq(irq_find_mapping(dra7xx->irq_domain,
> - ffs(reg) - 1));
> + for_each_set_bit(bit, &reg, PCI_NUM_INTX) {
> + virq = irq_find_mapping(dra7xx->irq_domain, bit);
> + if (virq)
> + generic_handle_irq(virq);
> + }
> break;
> }
>
>