[PATCH 3.4 213/214] PCI/ASPM: Dont touch ASPM if forcibly disabled

Greg Kroah-Hartman
2014-06-05T04:23:17Z

From: Joe Lawrence <joe.lawrence@stratus.com>

commit a26d5ecb3201c11e03663a8f4a7dedc0c5f85c07 upstream.

Don't allocate and track PCIe ASPM state when "pcie_aspm=off" is specified
on the kernel command line.

Based-on-patch-from: Matthew Garrett <mjg59@srcf.ucam.org>
Signed-off-by: Joe Lawrence <joe.lawrence@stratus.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: David Bulkow <david.bulkow@stratus.com>
Acked-by: Myron Stowe <myron.stowe@redhat.com>
[wyj: Backported to 3.4: context adjust]
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/pci/pcie/aspm.c | 3 +++
1 file changed, 3 insertions(+)

--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -583,6 +583,9 @@ void pcie_aspm_init_link_state(struct pc
struct pcie_link_state *link;
int blacklist = !!pcie_aspm_sanity_check(pdev);

+ if (!aspm_support_enabled)
+ return;
+
if (!pci_is_pcie(pdev) || pdev->link_state)
return;
if (pdev->pcie_type != PCI_EXP_TYPE_ROOT_PORT &&