Hi, On 4/24/23 10:55 PM, Kai-Heng Feng wrote: > On Tue, Apr 25, 2023 at 7:47 AM Sathyanarayanan Kuppuswamy > <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> wrote: >> >> >> >> On 4/23/23 10:52 PM, Kai-Heng Feng wrote: >>> PCIe service that shares IRQ with PME may cause spurious wakeup on >>> system suspend. >>> >>> PCIe Base Spec 5.0, section 5.2 "Link State Power Management" states >>> that TLP and DLLP transmission is disabled for a Link in L2/L3 Ready >>> (D3hot), L2 (D3cold with aux power) and L3 (D3cold), so we don't lose >>> much here to disable AER during system suspend. >>> >>> This is very similar to previous attempts to suspend AER and DPC [1], >>> but with a different reason. >>> >>> [1] https://lore.kernel.org/linux-pci/20220408153159.106741-1-kai.heng.feng@xxxxxxxxxxxxx/ >>> Link: https://bugzilla.kernel.org/show_bug.cgi?id=216295 >>> >>> Reviewed-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> >>> Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> >>> --- >> >> IIUC, you encounter AER errors during the suspend/resume process, which >> results in AER IRQ. Because AER and PME share an IRQ, it is regarded as a >> spurious wake-up IRQ. So to fix it, you want to disable AER reporting, >> right? > > Yes. That's exactly what happened. > >> >> It looks like it is harmless to disable the AER during the suspend/resume >> path. But, I am wondering why we get these errors? Did you check what errors >> you get during the suspend/resume path? Are these errors valid? > > I really don't know. I think it's similar to the reasoning in commit > b07461a8e45b ("PCI/AER: Clear error status registers during > enumeration and restore"): "AER errors might be recorded when > powering-on devices. These errors can be ignored, ...". > For this case, it happens when powering-off the device (D3cold) via > turning off power resources. Got it. Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> > > Kai-Heng > >> >> >>> drivers/pci/pcie/aer.c | 22 ++++++++++++++++++++++ >>> 1 file changed, 22 insertions(+) >>> >>> diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c >>> index 1420e1f27105..9c07fdbeb52d 100644 >>> --- a/drivers/pci/pcie/aer.c >>> +++ b/drivers/pci/pcie/aer.c >>> @@ -1356,6 +1356,26 @@ static int aer_probe(struct pcie_device *dev) >>> return 0; >>> } >>> >>> +static int aer_suspend(struct pcie_device *dev) >>> +{ >>> + struct aer_rpc *rpc = get_service_data(dev); >>> + struct pci_dev *pdev = rpc->rpd; >>> + >>> + aer_disable_irq(pdev); >>> + >>> + return 0; >>> +} >>> + >>> +static int aer_resume(struct pcie_device *dev) >>> +{ >>> + struct aer_rpc *rpc = get_service_data(dev); >>> + struct pci_dev *pdev = rpc->rpd; >>> + >>> + aer_enable_irq(pdev); >>> + >>> + return 0; >>> +} >>> + >>> /** >>> * aer_root_reset - reset Root Port hierarchy, RCEC, or RCiEP >>> * @dev: pointer to Root Port, RCEC, or RCiEP >>> @@ -1420,6 +1440,8 @@ static struct pcie_port_service_driver aerdriver = { >>> .service = PCIE_PORT_SERVICE_AER, >>> >>> .probe = aer_probe, >>> + .suspend = aer_suspend, >>> + .resume = aer_resume, >>> .remove = aer_remove, >>> }; >>> >> >> -- >> Sathyanarayanan Kuppuswamy >> Linux Kernel Developer -- Sathyanarayanan Kuppuswamy Linux Kernel Developer
