From andrew.patterson@hp.com Wed Jan 23 09:42:16 2008 From: Andrew Patterson Date: Tue, 22 Jan 2008 17:18:27 -0700 Subject: PCI: Run ACPI _OSC method on root bridges only To: linux-pci@vger.kernel.org Cc: linux-kernel@vger.kernel.org, lenb@kernel.org, gregkh@suse.de, matthew@wil.cx, tom.l.nguyen@intel.com, linux-acpi@vger.kernel.org, Andrew Patterson Message-ID: <20080123001827.28190.7908.stgit@bluto.andrew> From: Andrew Patterson According to the PCI Firmware Specification Revision 3.0 section 4.5, _OSC should only be called on a root brdige. Here is the relevant passage: "The _OSC interface defined in this section applies only to Host Bridge ACPI devices that originate PCI, PCI-X, or PCI Express hierarchies". Changed the code to find the parent root bridge of the device and call _OSC on that. Signed-off-by: Andrew Patterson Signed-off-by: Greg Kroah-Hartman --- drivers/pci/pcie/aer/aerdrv_acpi.c | 22 ++++++---------------- 1 file changed, 6 insertions(+), 16 deletions(-) --- a/drivers/pci/pcie/aer/aerdrv_acpi.c +++ b/drivers/pci/pcie/aer/aerdrv_acpi.c @@ -31,23 +31,13 @@ int aer_osc_setup(struct pcie_device *pc { acpi_status status = AE_NOT_FOUND; struct pci_dev *pdev = pciedev->port; - acpi_handle handle = DEVICE_ACPI_HANDLE(&pdev->dev); - struct pci_bus *parent; + acpi_handle handle = 0; - while (!handle) { - if (!pdev || !pdev->bus->parent) - break; - parent = pdev->bus->parent; - if (!parent->self) - /* Parent must be a host bridge */ - handle = acpi_get_pci_rootbridge_handle( - pci_domain_nr(parent), - parent->number); - else - handle = DEVICE_ACPI_HANDLE( - &(parent->self->dev)); - pdev = parent->self; - } + /* Find root host bridge */ + while (pdev->bus && pdev->bus->self) + pdev = pdev->bus->self; + handle = acpi_get_pci_rootbridge_handle( + pci_domain_nr(pdev->bus), pdev->bus->number); if (handle) { pcie_osc_support_set(OSC_EXT_PCI_CONFIG_SUPPORT);