3 files changed, 8 insertions, 33 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();
 
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index 820740a22e94..7d4fcdc512aa 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -782,24 +782,6 @@ void pci_disable_link_state(struct pci_dev *pdev, int state)
 }
 EXPORT_SYMBOL(pci_disable_link_state);
 
-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
-         */
-        list_for_each_entry(child, &bus->devices, bus_list) {
-                __pci_disable_link_state(child, PCIE_LINK_STATE_L0S |
-                                         PCIE_LINK_STATE_L1 |
-                                         PCIE_LINK_STATE_CLKPM,
-                                         false, true);
-        }
-}
-
 static int pcie_aspm_set_policy(const char *val, struct kernel_param *kp)
 {
         int i;
diff --git a/include/linux/pci-aspm.h b/include/linux/pci-aspm.h
index 8af4610c2e41..207c561fb40e 100644
--- a/include/linux/pci-aspm.h
+++ b/include/linux/pci-aspm.h
@@ -29,7 +29,6 @@ void pcie_aspm_pm_state_change(struct pci_dev *pdev);
 void pcie_aspm_powersave_config_link(struct pci_dev *pdev);
 void pci_disable_link_state(struct pci_dev *pdev, int state);
 void pci_disable_link_state_locked(struct pci_dev *pdev, int state);
-void pcie_clear_aspm(struct pci_bus *bus);
 void pcie_no_aspm(void);
 #else
 static inline void pcie_aspm_init_link_state(struct pci_dev *pdev)
@@ -47,9 +46,6 @@ static inline void pcie_aspm_powersave_config_link(struct pci_dev *pdev)
 static inline void pci_disable_link_state(struct pci_dev *pdev, int state)
 {
 }
-static inline void pcie_clear_aspm(struct pci_bus *bus)
-{
-}
 static inline void pcie_no_aspm(void)
 {
 }