2022-10-06 14:28:20

by Manivannan Sadhasivam

Subject: [PATCH v3 1/5] PCI: dra7xx: Use threaded IRQ handler for "dra7xx-pcie-main" IRQ

The "dra7xx-pcie-main" hard IRQ handler is just printing the IRQ status
and calling the dw_pcie_ep_linkup() API if LINK_UP status is set. But the
execution of dw_pcie_ep_linkup() depends on the EPF driver and may take
more time depending on the EPF implementation.

In general, hard IRQ handlers are supposed to return quickly and not block
for so long. Moreover, there is no real need of the current IRQ handler to
be a hard IRQ handler. So switch to the threaded IRQ handler for the
"dra7xx-pcie-main" IRQ.

Signed-off-by: Manivannan Sadhasivam <[email protected]>
---
drivers/pci/controller/dwc/pci-dra7xx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/pci/controller/dwc/pci-dra7xx.c b/drivers/pci/controller/dwc/pci-dra7xx.c
index 38462ed11d07..4ae807e7cf79 100644
--- a/drivers/pci/controller/dwc/pci-dra7xx.c
+++ b/drivers/pci/controller/dwc/pci-dra7xx.c
@@ -840,7 +840,7 @@ static int dra7xx_pcie_probe(struct platform_device *pdev)
}
dra7xx->mode = mode;

- ret = devm_request_irq(dev, irq, dra7xx_pcie_irq_handler,
+ ret = devm_request_threaded_irq(dev, irq, NULL, dra7xx_pcie_irq_handler,
IRQF_SHARED, "dra7xx-pcie-main", dra7xx);
if (ret) {
dev_err(dev, "failed to request irq\n");
--
2.25.1

2022-10-11 13:39:35

by Kishon Vijay Abraham I

Subject: Re: [PATCH v3 1/5] PCI: dra7xx: Use threaded IRQ handler for "dra7xx-pcie-main" IRQ

On 06/10/22 7:19 pm, Manivannan Sadhasivam wrote:
> The "dra7xx-pcie-main" hard IRQ handler is just printing the IRQ status
> and calling the dw_pcie_ep_linkup() API if LINK_UP status is set. But the
> execution of dw_pcie_ep_linkup() depends on the EPF driver and may take
> more time depending on the EPF implementation.
>
> In general, hard IRQ handlers are supposed to return quickly and not block
> for so long. Moreover, there is no real need of the current IRQ handler to
> be a hard IRQ handler. So switch to the threaded IRQ handler for the
> "dra7xx-pcie-main" IRQ.
>
> Signed-off-by: Manivannan Sadhasivam <[email protected]>

Acked-by: Kishon Vijay Abraham I <[email protected]>
> ---
> drivers/pci/controller/dwc/pci-dra7xx.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/pci/controller/dwc/pci-dra7xx.c b/drivers/pci/controller/dwc/pci-dra7xx.c
> index 38462ed11d07..4ae807e7cf79 100644
> --- a/drivers/pci/controller/dwc/pci-dra7xx.c
> +++ b/drivers/pci/controller/dwc/pci-dra7xx.c
> @@ -840,7 +840,7 @@ static int dra7xx_pcie_probe(struct platform_device *pdev)
> }
> dra7xx->mode = mode;
>
> - ret = devm_request_irq(dev, irq, dra7xx_pcie_irq_handler,
> + ret = devm_request_threaded_irq(dev, irq, NULL, dra7xx_pcie_irq_handler,
> IRQF_SHARED, "dra7xx-pcie-main", dra7xx);
> if (ret) {
> dev_err(dev, "failed to request irq\n");
>