On Wed, Sep 13, 2023 at 11:36:49AM -0500, Mario Limonciello wrote: > On 9/13/2023 09:31, Lukas Wunner wrote: > > If this only affects system sleep, not runtime PM, what you can do is > > define a DECLARE_PCI_FIXUP_SUSPEND_LATE() which calls pci_d3cold_disable() > > and also define a DECLARE_PCI_FIXUP_CLASS_RESUME_EARLY() which calls > > pci_d3cold_enable(). > > > > And I think you can make those calls conditional on pm_suspend_no_platform() > > to constrain to s2idle. > > > > User space should still be able to influence runtime PM via the > > d3cold_allowed flag (unless I'm missing something). > > The part you're missing is that D3hot is affected by this issue too, > otherwise it would be a good proposal. I recall that in an earlier version of the patch, you solved the issue by amending pci_bridge_d3_possible(). Changing the dev->no_d3cold flag indirectly influences the bridge_d3 flag (through pci_dev_check_d3cold() and pci_bridge_d3_update()). If dev->no_d3cold is set on a device below a port, that port is prevented from entring D3hot because it would result in the device effectively being in D3cold. So you might want to take a closer look at this approach despite the flag suggesting that it only influences D3cold. Thanks, Lukas
