Merge branch 'pci/misc' into next

* pci/misc:
  PCI: Read capability list as dwords, not bytes
  PCI: Don't clear ASPM bits when the FADT declares it's unsupported
  PCI: Clarify policy for vendor IDs in pci.txt
  PCI/ACPI: Optimize device state transition delays
  PCI: Export pci_find_host_bridge() for use inside PCI core
  PCI: Make a shareable UUID for PCI firmware ACPI _DSM
  PCI: Fix typo in Thunderbolt kernel message

1 files changed, 8 insertions, 11 deletions

diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index 68a5f712cd19..1b5569c092c6 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -423,8 +423,7 @@ out:
 }
 EXPORT_SYMBOL(acpi_pci_osc_control_set);
 
-static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
-                                 int *clear_aspm)
+static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm)
 {
         u32 support, control, requested;
         acpi_status status;
@@ -495,10 +494,12 @@ static void negotiate_os_control(struct acpi_pci_root *root, int *no_aspm,
                 decode_osc_control(root, "OS now controls", control);
                 if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
                         /*
-                         * We have ASPM control, but the FADT indicates
-                         * that it's unsupported. Clear it.
+                         * We have ASPM control, but the FADT indicates that
+                         * it's unsupported. Leave existing configuration
+                         * intact and prevent the OS from touching it.
                          */
-                        *clear_aspm = 1;
+                        dev_info(&device->dev, "FADT indicates ASPM is unsupported, using BIOS configuration\n");
+                        *no_aspm = 1;
                 }
         } else {
                 decode_osc_control(root, "OS requested", requested);
@@ -525,7 +526,7 @@ static int acpi_pci_root_add(struct acpi_device *device,
         int result;
         struct acpi_pci_root *root;
         acpi_handle handle = device->handle;
-        int no_aspm = 0, clear_aspm = 0;
+        int no_aspm = 0;
         bool hotadd = system_state != SYSTEM_BOOTING;
 
         root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
@@ -584,7 +585,7 @@ static int acpi_pci_root_add(struct acpi_device *device,
 
         root->mcfg_addr = acpi_pci_root_get_mcfg_addr(handle);
 
-        negotiate_os_control(root, &no_aspm, &clear_aspm);
+        negotiate_os_control(root, &no_aspm);
 
         /*
          * TBD: Need PCI interface for enumeration/configuration of roots.
@@ -607,10 +608,6 @@ static int acpi_pci_root_add(struct acpi_device *device,
                 goto remove_dmar;
         }
 
-        if (clear_aspm) {
-                dev_info(&device->dev, "Disabling ASPM (FADT indicates it is unsupported)\n");
-                pcie_clear_aspm(root->bus);
-        }
         if (no_aspm)
                 pcie_no_aspm();