From 2d9c86774756193edff2a2a9077264f666c626de Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Mon, 30 Jul 2012 22:40:32 +0200 Subject: ACPI / PCI: Do not try to acquire _OSC control if that is hopeless If acpi_pci_osc_support() fails for the given flags, it doesn't make sense to call acpi_pci_osc_control_set() down the road for the same flags, because it will certainly fail too. Moreover, problem diagnostics is then harder, because it is not too easy to identify the reason of the _OSC failure in those cases. For this reason, check the status returned by acpi_pci_osc_support() for PCIe support flags and do not attempt to execute acpi_pci_osc_control_set() for those flags and print a message if it's "failure". For compatibility with the existing code, disable ASPM in that case too. Signed-off-by: Rafael J. Wysocki Signed-off-by: Len Brown diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c index 7aff631..c86b392 100644 --- a/drivers/acpi/pci_root.c +++ b/drivers/acpi/pci_root.c @@ -571,8 +571,15 @@ static int __devinit acpi_pci_root_add(struct acpi_device *device) OSC_CLOCK_PWR_CAPABILITY_SUPPORT; if (pci_msi_enabled()) flags |= OSC_MSI_SUPPORT; - if (flags != base_flags) - acpi_pci_osc_support(root, flags); + if (flags != base_flags) { + status = acpi_pci_osc_support(root, flags); + if (ACPI_FAILURE(status)) { + dev_info(root->bus->bridge, "ACPI _OSC support " + "notification failed, disabling PCIe ASPM\n"); + pcie_no_aspm(); + flags = base_flags; + } + } if (!pcie_ports_disabled && (flags & ACPI_PCIE_REQ_SUPPORT) == ACPI_PCIE_REQ_SUPPORT) { -- cgit v0.10.2