On Mon, Oct 02, 2023 at 01:09:06PM -0500, Mario Limonciello wrote: > Iain reports that USB devices can't be used to wake a Lenovo Z13 from > suspend. This occurs because on some AMD platforms, even though the Root > Ports advertise PME_Support for D3hot and D3cold, they don't handle PME > messages and generate wakeup interrupts from those states when amd-pmc has > put the platform in a hardware sleep state. > > Iain reported this on an AMD Rembrandt platform, but it also affects > Phoenix SoCs. On Iain's system, a USB4 router below the affected Root Port > generates the PME. To avoid this issue, disable D3 for the root port > associated with USB4 controllers at suspend time. > > Restore D3 support at resume so that it can be used by runtime suspend. > The amd-pmc driver doesn't put the platform in a hardware sleep state for > runtime suspend, so PMEs work as advertised. > > Cc: stable@xxxxxxxxxxxxxxx # 6.1.y: 70b70a4: PCI/sysfs: Protect driver's D3cold preference from user space > Cc: stable@xxxxxxxxxxxxxxx # 6.5.y: 70b70a4: PCI/sysfs: Protect driver's D3cold preference from user space > Cc: stable@xxxxxxxxxxxxxxx # 6.6.y: 70b70a4: PCI/sysfs: Protect driver's D3cold preference from user space > Link: https://learn.microsoft.com/en-us/windows-hardware/design/device-experiences/platform-design-for-modern-standby#low-power-core-silicon-cpu-soc-dram [1] > Fixes: 9d26d3a8f1b0 ("PCI: Put PCIe ports into D3 during suspend") > Reported-by: Iain Lane <iain@xxxxxxxxxxxxxxxxxxx> > Closes: https://forums.lenovo.com/t5/Ubuntu/Z13-can-t-resume-from-suspend-with-external-USB-keyboard/m-p/5217121 > Signed-off-by: Mario Limonciello <mario.limonciello@xxxxxxx> > --- > v20-v21: > * Rewrite commit message, lifting most of what Bjorn clipped down to on v20. > * Use pci_d3cold_disable()/pci_d3cold_enable() instead > * Do the quirk on the USB4 controller instead of RP->USB->RP > --- > drivers/pci/quirks.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 44 insertions(+) > > diff --git a/drivers/pci/quirks.c b/drivers/pci/quirks.c > index eeec1d6f9023..5674065011e7 100644 > --- a/drivers/pci/quirks.c > +++ b/drivers/pci/quirks.c > @@ -6188,3 +6188,47 @@ DECLARE_PCI_FIXUP_HEADER(PCI_VENDOR_ID_INTEL, 0x9a31, dpc_log_size); > DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_XILINX, 0x5020, of_pci_make_dev_node); > DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_XILINX, 0x5021, of_pci_make_dev_node); > DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_REDHAT, 0x0005, of_pci_make_dev_node); > + > +#ifdef CONFIG_SUSPEND > +/* > + * Root Ports on some AMD SoCs advertise PME_Support for D3hot and D3cold, but > + * if the SoC is put into a hardware sleep state by the amd-pmc driver, the > + * Root Ports don't generate wakeup interrupts for USB devices. > + * > + * When suspending, disable D3 support for the Root Port so we don't use it. > + * Restore D3 support when resuming. > + */ > +static void quirk_enable_rp_d3cold(struct pci_dev *dev) > +{ > + pci_d3cold_enable(pcie_find_root_port(dev)); > +} > + > +static void quirk_disable_rp_d3cold_suspend(struct pci_dev *dev) > +{ > + struct pci_dev *rp; > + > + /* > + * PM_SUSPEND_ON means we're doing runtime suspend, which means > + * amd-pmc will not be involved so PMEs during D3 work as advertised. > + * > + * The PMEs *do* work if amd-pmc doesn't put the SoC in the hardware > + * sleep state, but we assume amd-pmc is always present. > + */ > + if (pm_suspend_target_state == PM_SUSPEND_ON) > + return; > + > + rp = pcie_find_root_port(dev); > + pci_d3cold_disable(rp); I think this prevents D3cold from being used at all, right? Two questions: - PME also doesn't work in D3hot, right? - Is it OK to use D3hot and D3cold if we don't have a wakeup device below the Root Port? I assume that scenario is possible? I like the fact that we don't have to walk the hierarchy with pci_walk_bus(). > + dev_info_once(&rp->dev, "quirk: disabling D3cold for suspend\n"); > +} > +/* Rembrandt (yellow_carp) */ > +DECLARE_PCI_FIXUP_SUSPEND(PCI_VENDOR_ID_AMD, 0x162e, quirk_disable_rp_d3cold_suspend); > +DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_AMD, 0x162e, quirk_enable_rp_d3cold); > +DECLARE_PCI_FIXUP_SUSPEND(PCI_VENDOR_ID_AMD, 0x162f, quirk_disable_rp_d3cold_suspend); > +DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_AMD, 0x162f, quirk_enable_rp_d3cold); > +/* Phoenix (pink_sardine) */ > +DECLARE_PCI_FIXUP_SUSPEND(PCI_VENDOR_ID_AMD, 0x1668, quirk_disable_rp_d3cold_suspend); > +DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_AMD, 0x1668, quirk_enable_rp_d3cold); > +DECLARE_PCI_FIXUP_SUSPEND(PCI_VENDOR_ID_AMD, 0x1669, quirk_disable_rp_d3cold_suspend); > +DECLARE_PCI_FIXUP_RESUME(PCI_VENDOR_ID_AMD, 0x1669, quirk_enable_rp_d3cold); > +#endif /* CONFIG_SUSPEND */ > -- > 2.34.1 >
