[cc += Mika] On Mon, Aug 09, 2021 at 12:24:12PM +0800, Kai-Heng Feng wrote: > Bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=213873 The last comment on this bugzilla says "BIOS will fix this." and the status is RESOLVED WILL_NOT_FIX. Why is the patch still necessary? > Some platforms cannot detect ethernet hotplug once its upstream port is > runtime suspended because PME isn't enabled in _OSC. If PME is not handled natively, why does the NIC runtime suspend? Shouldn't this be fixed in the NIC driver by keeping the device runtime active if PME cannot be used? > Disallow port runtime suspend when any child device requires wakeup, so > pci_pme_list_scan() can still read the PME status from the devices > behind the port. pci_pme_list_scan() is for broken devices which fail to signal PME. Is this NIC really among them or does PME fail merely because it's not granted to OSPM? > --- a/drivers/pci/pcie/portdrv_pci.c > +++ b/drivers/pci/pcie/portdrv_pci.c > @@ -59,14 +59,30 @@ static int pcie_port_runtime_suspend(struct device *dev) > return pcie_port_device_runtime_suspend(dev); > } > > +static int pcie_port_wakeup_check(struct device *dev, void *data) > +{ > + struct pci_dev *pdev = to_pci_dev(dev); > + > + if (!pdev) > + return 0; > + > + return pdev->wakeup_prepared; > +} > + > static int pcie_port_runtime_idle(struct device *dev) > { > + struct pci_dev *pdev = to_pci_dev(dev); > + > + if (!pcie_port_find_device(pdev, PCIE_PORT_SERVICE_PME) && > + device_for_each_child(dev, NULL, pcie_port_wakeup_check)) > + return -EBUSY; > + > /* > * Assume the PCI core has set bridge_d3 whenever it thinks the port > * should be good to go to D3. Everything else, including moving > * the port to D3, is handled by the PCI core. > */ > - return to_pci_dev(dev)->bridge_d3 ? 0 : -EBUSY; > + return pdev->bridge_d3 ? 0 : -EBUSY; If an additional check is necessary for this issue, it should be integrated into pci_dev_check_d3cold() instead of pcie_port_runtime_idle(). Thanks, Lukas
