On Fri, Apr 08, 2022 at 08:29:01PM +0200, Rafael J. Wysocki wrote: > From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> > Subject: [PATCH] PCI: PM: Power up all devices during runtime resume > > Currently, endpoint devices may not be powered up entirely during > runtime resume that follows a D3hot -> D0 transition of the parent > bridge. > > Namely, even if the power state of an endpoint device, as indicated > by its PCI_PM_CTRL register, is D0 after powering up its parent > bridge, it may be still necessary to bring its ACPI companion into > D0 and that should be done before accessing it. However, the current > code assumes that reading the PCI_PM_CTRL register is sufficient to > establish the endpoint device's power state, which may lead to > problems. > > Address that by forcing a power-up of all PCI devices, including the > platform firmware part of it, during runtime resume. > > Link: https://lore.kernel.org/linux-pm/11967527.O9o76ZdvQC@kreacher > Fixes: 5775b843a619 ("PCI: Restore config space on runtime resume despite being unbound") > Reported-by: Abhishek Sahu <abhsahu@xxxxxxxxxx> > Tested-by: Abhishek Sahu <abhsahu@xxxxxxxxxx> > Reviewed-by: Mika Westerberg <mika.westerberg@xxxxxxxxxxxxxxx> > Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx> I replaced the v1 patch with this one on pci/pm, thanks! > --- > > v1 -> v2: > * Move pci_pm_default_resume_early() away from #ifdef CONFIG_PM_SLEEP. > * Add R-by from Mika. > > --- > drivers/pci/pci-driver.c | 10 +++++----- > 1 file changed, 5 insertions(+), 5 deletions(-) > > Index: linux-pm/drivers/pci/pci-driver.c > =================================================================== > --- linux-pm.orig/drivers/pci/pci-driver.c > +++ linux-pm/drivers/pci/pci-driver.c > @@ -551,10 +551,6 @@ static void pci_pm_default_resume(struct > pci_enable_wake(pci_dev, PCI_D0, false); > } > > -#endif > - > -#ifdef CONFIG_PM_SLEEP > - > static void pci_pm_default_resume_early(struct pci_dev *pci_dev) > { > pci_power_up(pci_dev); > @@ -563,6 +559,10 @@ static void pci_pm_default_resume_early( > pci_pme_restore(pci_dev); > } > > +#endif > + > +#ifdef CONFIG_PM_SLEEP > + > /* > * Default "suspend" method for devices that have no driver provided suspend, > * or not even a driver at all (second part). > @@ -1312,7 +1312,7 @@ static int pci_pm_runtime_resume(struct > * to a driver because although we left it in D0, it may have gone to > * D3cold when the bridge above it runtime suspended. > */ > - pci_restore_standard_config(pci_dev); > + pci_pm_default_resume_early(pci_dev); > > if (!pci_dev->driver) > return 0; > > >
