On Thu, Sep 29, 2022 at 5:46 AM Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote: > > On Wed, Jul 27, 2022 at 09:32:51AM +0800, 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/ > > Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=216295 > > > > Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx> > > --- > > drivers/pci/pcie/aer.c | 23 ++++++++++++++++++++++- > > 1 file changed, 22 insertions(+), 1 deletion(-) > > > > diff --git a/drivers/pci/pcie/aer.c b/drivers/pci/pcie/aer.c > > index 7952e5efd6cf3..60cc373754af2 100644 > > --- a/drivers/pci/pcie/aer.c > > +++ b/drivers/pci/pcie/aer.c > > @@ -1372,6 +1372,26 @@ 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); > > + > > + if (dev->shared_pme_irq) > > + aer_disable_rootport(rpc); > > aer_disable_rootport() seems like it might be overkill. IIUC, what > we want to do here is disable AER interrupts, which should only > require clearing ROOT_PORT_INTR_ON_MESG_MASK in PCI_ERR_ROOT_COMMAND. > > In addition to clearing ROOT_PORT_INTR_ON_MESG_MASK, > aer_disable_rootport() traverses the whole hierarchy, clearing > PCI_EXP_AER_FLAGS (CERE | NFERE | FERE | URRE) in PCI_EXP_DEVCTL. > I don't think these DEVCTL bits control interrupt generation, so I > don't know why we need to touch them. > > aer_disable_rootport() also clears PCI_ERR_ROOT_STATUS, which I think > we should not do during suspend either. We might want to clear it > on resume (which we already do in pci_restore_state()), but I think > generally we should preserve error information as long as it doesn't > cause trouble. > > Your thoughts please :) Sorry for the belated response. Clearing ROOT_PORT_INTR_ON_MESG_MASK along to disable interrupt can solve the issue too. And I agree that the AER information should be preserved too. Kai-Heng > > > + > > + return 0; > > +} > > + > > +static int aer_resume(struct pcie_device *dev) > > +{ > > + struct aer_rpc *rpc = get_service_data(dev); > > + > > + if (dev->shared_pme_irq) > > + aer_enable_rootport(rpc); > > + > > + return 0; > > +} > > + > > /** > > * aer_root_reset - reset Root Port hierarchy, RCEC, or RCiEP > > * @dev: pointer to Root Port, RCEC, or RCiEP > > @@ -1441,8 +1461,9 @@ static struct pcie_port_service_driver aerdriver = { > > .name = "aer", > > .port_type = PCIE_ANY_PORT, > > .service = PCIE_PORT_SERVICE_AER, > > - > > .probe = aer_probe, > > + .suspend = aer_suspend, > > + .resume = aer_resume, > > .remove = aer_remove, > > }; > > > > -- > > 2.36.1 > >
