| Message ID | 1521042648-20522-1-git-send-email-poza@codeaurora.org |
|---|---|
| State | Superseded |
| Delegated to: | Bjorn Helgaas |
| Headers | show |
| Series | [v2] PCI/DPC: Fix PCI legacy interrupt acknowledgement | expand |
On Wed, Mar 14, 2018 at 09:20:48PM +0530, Oza Pawandeep wrote: > 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@codeaurora.org> Thanks, this looks good to me. Reviewed-by: Keith Busch <keith
On Wed, Mar 14, 2018 at 02:52:30PM -0600, Keith Busch wrote: > > Reviewed-by: Keith Busch <keith Whoops, I accidentally truncated my message. My correct tag: Reviewed-by: Keith Busch <keith.busch@intel.com>
On 2018-03-15 02:22, Keith Busch wrote: > On Wed, Mar 14, 2018 at 09:20:48PM +0530, Oza Pawandeep wrote: >> 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@codeaurora.org> > > Thanks, this looks good to me. > > Reviewed-by: Keith Busch <keith checkpatch script shows WARNING: 'acknowledgement' may be misspelled - perhaps 'acknowledgment'? but dictionaries shows acknowledgement. Regards, Oza.
On 2018-03-15 02:26, Keith Busch wrote: > On Wed, Mar 14, 2018 at 02:52:30PM -0600, Keith Busch wrote: >> >> Reviewed-by: Keith Busch <keith > > Whoops, I accidentally truncated my message. My correct tag: > > Reviewed-by: Keith Busch <keith.busch@intel.com> Hi Bjorn, Can this be merged ? Regards, Oza.
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;
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@codeaurora.org>