Current DPC driver acknowledges the interrupt in deferred work, which works since MSI are edge triggered. But when MSI is disabled (e.g. pci=nomsi boot option) port service driver falls back to PCI legacy INT interrupt. With current code we do not acknowledge the interrupt back in dpc_irq() and we get dpc interrupt storm. This patch acknowledges the interrupt in interrupt handler. Signed-off-by: Oza Pawandeep <poza@xxxxxxxxxxxxxx> diff --git a/drivers/pci/pcie/pcie-dpc.c b/drivers/pci/pcie/pcie-dpc.c index 38e40c6..9c05120 100644 --- a/drivers/pci/pcie/pcie-dpc.c +++ b/drivers/pci/pcie/pcie-dpc.c @@ -112,7 +112,7 @@ static void dpc_work(struct work_struct *work) } pci_write_config_word(pdev, cap + PCI_EXP_DPC_STATUS, - PCI_EXP_DPC_STATUS_TRIGGER | PCI_EXP_DPC_STATUS_INTERRUPT); + PCI_EXP_DPC_STATUS_TRIGGER); pci_read_config_word(pdev, cap + PCI_EXP_DPC_CTL, &ctl); pci_write_config_word(pdev, cap + PCI_EXP_DPC_CTL, @@ -222,6 +222,9 @@ static irqreturn_t dpc_irq(int irq, void *context) if (dpc->rp_extensions && reason == 3 && ext_reason == 0) dpc_process_rp_pio_error(dpc); + pci_write_config_word(pdev, cap + PCI_EXP_DPC_STATUS, + PCI_EXP_DPC_STATUS_INTERRUPT); + schedule_work(&dpc->work); return IRQ_HANDLED; -- Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc., a Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.
