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SubjectRe: [PATCH v1 3/9] PCI/PM: Clear PCIe PME Status bit for Root Complex Event Collectors
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On Wednesday, March 7, 2018 7:13:40 AM CET Bjorn Helgaas wrote:
> From: Bjorn Helgaas <bhelgaas@google.com>
>
> Per PCIe r4.0, sec 6.1.6, Root Complex Event Collectors can generate PME
> interrupts on behalf of Root Complex Integrated Endpoints.
>
> Linux does not currently enable PME interrupts from RC Event Collectors,
> but fe31e69740ed ("PCI/PCIe: Clear Root PME Status bits early during system
> resume") suggests PME interrupts may be enabled by the platform for ACPI-
> based runtime wakeup.
>
> Clear the PCIe PME Status bit for Root Complex Event Collectors during
> resume, just like we already do for Root Ports.
>
> If the BIOS enables PME interrupts for an event collector and neglects to
> clear the status bit on resume, this change should fix the same bug as
> fe31e69740ed (PMEs not working after waking from a sleep state), but for
> Root Complex Integrated Endpoints.
>
> Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
> ---
> drivers/pci/pci-driver.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/drivers/pci/pci-driver.c b/drivers/pci/pci-driver.c
> index bf0704b75f79..38ee7c8b4d1a 100644
> --- a/drivers/pci/pci-driver.c
> +++ b/drivers/pci/pci-driver.c
> @@ -533,7 +533,8 @@ static void pcie_resume_early(struct pci_dev *pci_dev)
> * bits now just in case (shouldn't hurt).
> */
> if (pci_is_pcie(pci_dev) &&
> - pci_pcie_type(pci_dev) == PCI_EXP_TYPE_ROOT_PORT)
> + (pci_pcie_type(pci_dev) == PCI_EXP_TYPE_ROOT_PORT ||
> + pci_pcie_type(pci_dev) == PCI_EXP_TYPE_RC_EC))
> pcie_clear_root_pme_status(pci_dev);
> }
>
>
>

Reveiwed-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>


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