PCI: Allow pcie_aspm=force even when FADT indicates it is unsupported

commit 9e16721498b0c3d3ebfa0b503c63d35c0a4c0642 upstream.

Right now using pcie_aspm=force will not enable ASPM if the FADT indicates
ASPM is unsupported.  However, the semantics of force should probably allow
for this, especially as they did before 3c076351c4 ("PCI: Rework ASPM
disable code")

This patch just skips the clearing of any ASPM setup that the firmware has
carried out on this bus if pcie_aspm=force is being used.

Reference: http://bugs.launchpad.net/bugs/962038
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 213753b283a6838174dd1fd409add971c7a363ae..449f257c8a827f65887cb1b31fd34b3c463f5cfa 100644 (file)
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -773,6 +773,9 @@ void pcie_clear_aspm(struct pci_bus *bus)
 {
        struct pci_dev *child;
 
+       if (aspm_force)
+               return;
+
        /*
         * Clear any ASPM setup that the firmware has carried out on this bus
         */