Merge remote-tracking branch 'pci/pri-changes' into x86/amd

10 files changed, 223 insertions, 87 deletions

diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c
index 2672c798272f..7aff6312ce7c 100644
--- a/drivers/acpi/pci_root.c
+++ b/drivers/acpi/pci_root.c
@@ -596,6 +596,13 @@ static int __devinit acpi_pci_root_add(struct acpi_device *device)
                 if (ACPI_SUCCESS(status)) {
                         dev_info(root->bus->bridge,
                                 "ACPI _OSC control (0x%02x) granted\n", flags);
+                        if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
+                                /*
+                                 * We have ASPM control, but the FADT indicates
+                                 * that it's unsupported. Clear it.
+                                 */
+                                pcie_clear_aspm(root->bus);
+                        }
                 } else {
                         dev_info(root->bus->bridge,
                                 "ACPI _OSC request failed (%s), "
diff --git a/drivers/pci/ats.c b/drivers/pci/ats.c
index 7ec56fb0bd78..2df49af6cc90 100644
--- a/drivers/pci/ats.c
+++ b/drivers/pci/ats.c
@@ -174,21 +174,22 @@ int pci_enable_pri(struct pci_dev *pdev, u32 reqs)
         u32 max_requests;
         int pos;
 
-        pos = pci_find_ext_capability(pdev, PCI_PRI_CAP);
+        pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
         if (!pos)
                 return -EINVAL;
 
-        pci_read_config_word(pdev, pos + PCI_PRI_CONTROL_OFF, &control);
-        pci_read_config_word(pdev, pos + PCI_PRI_STATUS_OFF,  &status);
-        if ((control & PCI_PRI_ENABLE) || !(status & PCI_PRI_STATUS_STOPPED))
+        pci_read_config_word(pdev, pos + PCI_PRI_CTRL, &control);
+        pci_read_config_word(pdev, pos + PCI_PRI_STATUS, &status);
+        if ((control & PCI_PRI_CTRL_ENABLE) ||
+            !(status & PCI_PRI_STATUS_STOPPED))
                 return -EBUSY;
 
-        pci_read_config_dword(pdev, pos + PCI_PRI_MAX_REQ_OFF, &max_requests);
+        pci_read_config_dword(pdev, pos + PCI_PRI_MAX_REQ, &max_requests);
         reqs = min(max_requests, reqs);
-        pci_write_config_dword(pdev, pos + PCI_PRI_ALLOC_REQ_OFF, reqs);
+        pci_write_config_dword(pdev, pos + PCI_PRI_ALLOC_REQ, reqs);
 
-        control |= PCI_PRI_ENABLE;
-        pci_write_config_word(pdev, pos + PCI_PRI_CONTROL_OFF, control);
+        control |= PCI_PRI_CTRL_ENABLE;
+        pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control);
 
         return 0;
 }
@@ -205,13 +206,13 @@ void pci_disable_pri(struct pci_dev *pdev)
         u16 control;
         int pos;
 
-        pos = pci_find_ext_capability(pdev, PCI_PRI_CAP);
+        pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
         if (!pos)
                 return;
 
-        pci_read_config_word(pdev, pos + PCI_PRI_CONTROL_OFF, &control);
-        control &= ~PCI_PRI_ENABLE;
-        pci_write_config_word(pdev, pos + PCI_PRI_CONTROL_OFF, control);
+        pci_read_config_word(pdev, pos + PCI_PRI_CTRL, &control);
+        control &= ~PCI_PRI_CTRL_ENABLE;
+        pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control);
 }
 EXPORT_SYMBOL_GPL(pci_disable_pri);
 
@@ -226,13 +227,13 @@ bool pci_pri_enabled(struct pci_dev *pdev)
         u16 control;
         int pos;
 
-        pos = pci_find_ext_capability(pdev, PCI_PRI_CAP);
+        pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
         if (!pos)
                 return false;
 
-        pci_read_config_word(pdev, pos + PCI_PRI_CONTROL_OFF, &control);
+        pci_read_config_word(pdev, pos + PCI_PRI_CTRL, &control);
 
-        return (control & PCI_PRI_ENABLE) ? true : false;
+        return (control & PCI_PRI_CTRL_ENABLE) ? true : false;
 }
 EXPORT_SYMBOL_GPL(pci_pri_enabled);
 
@@ -248,17 +249,17 @@ int pci_reset_pri(struct pci_dev *pdev)
         u16 control;
         int pos;
 
-        pos = pci_find_ext_capability(pdev, PCI_PRI_CAP);
+        pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
         if (!pos)
                 return -EINVAL;
 
-        pci_read_config_word(pdev, pos + PCI_PRI_CONTROL_OFF, &control);
-        if (control & PCI_PRI_ENABLE)
+        pci_read_config_word(pdev, pos + PCI_PRI_CTRL, &control);
+        if (control & PCI_PRI_CTRL_ENABLE)
                 return -EBUSY;
 
-        control |= PCI_PRI_RESET;
+        control |= PCI_PRI_CTRL_RESET;
 
-        pci_write_config_word(pdev, pos + PCI_PRI_CONTROL_OFF, control);
+        pci_write_config_word(pdev, pos + PCI_PRI_CTRL, control);
 
         return 0;
 }
@@ -281,14 +282,14 @@ bool pci_pri_stopped(struct pci_dev *pdev)
         u16 control, status;
         int pos;
 
-        pos = pci_find_ext_capability(pdev, PCI_PRI_CAP);
+        pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
         if (!pos)
                 return true;
 
-        pci_read_config_word(pdev, pos + PCI_PRI_CONTROL_OFF, &control);
-        pci_read_config_word(pdev, pos + PCI_PRI_STATUS_OFF,  &status);
+        pci_read_config_word(pdev, pos + PCI_PRI_CTRL, &control);
+        pci_read_config_word(pdev, pos + PCI_PRI_STATUS, &status);
 
-        if (control & PCI_PRI_ENABLE)
+        if (control & PCI_PRI_CTRL_ENABLE)
                 return false;
 
         return (status & PCI_PRI_STATUS_STOPPED) ? true : false;
@@ -310,15 +311,15 @@ int pci_pri_status(struct pci_dev *pdev)
         u16 status, control;
         int pos;
 
-        pos = pci_find_ext_capability(pdev, PCI_PRI_CAP);
+        pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PRI);
         if (!pos)
                 return -EINVAL;
 
-        pci_read_config_word(pdev, pos + PCI_PRI_CONTROL_OFF, &control);
-        pci_read_config_word(pdev, pos + PCI_PRI_STATUS_OFF,  &status);
+        pci_read_config_word(pdev, pos + PCI_PRI_CTRL, &control);
+        pci_read_config_word(pdev, pos + PCI_PRI_STATUS, &status);
 
         /* Stopped bit is undefined when enable == 1, so clear it */
-        if (control & PCI_PRI_ENABLE)
+        if (control & PCI_PRI_CTRL_ENABLE)
                 status &= ~PCI_PRI_STATUS_STOPPED;
 
         return status;
@@ -341,25 +342,25 @@ int pci_enable_pasid(struct pci_dev *pdev, int features)
         u16 control, supported;
         int pos;
 
-        pos = pci_find_ext_capability(pdev, PCI_PASID_CAP);
+        pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID);
         if (!pos)
                 return -EINVAL;
 
-        pci_read_config_word(pdev, pos + PCI_PASID_CONTROL_OFF, &control);
-        pci_read_config_word(pdev, pos + PCI_PASID_CAP_OFF,     &supported);
+        pci_read_config_word(pdev, pos + PCI_PASID_CTRL, &control);
+        pci_read_config_word(pdev, pos + PCI_PASID_CAP, &supported);
 
-        if (!(supported & PCI_PASID_ENABLE))
+        if (control & PCI_PASID_CTRL_ENABLE)
                 return -EINVAL;
 
-        supported &= PCI_PASID_EXEC | PCI_PASID_PRIV;
+        supported &= PCI_PASID_CAP_EXEC | PCI_PASID_CAP_PRIV;
 
         /* User wants to enable anything unsupported? */
         if ((supported & features) != features)
                 return -EINVAL;
 
-        control = PCI_PASID_ENABLE | features;
+        control = PCI_PASID_CTRL_ENABLE | features;
 
-        pci_write_config_word(pdev, pos + PCI_PASID_CONTROL_OFF, control);
+        pci_write_config_word(pdev, pos + PCI_PASID_CTRL, control);
 
         return 0;
 }
@@ -375,11 +376,11 @@ void pci_disable_pasid(struct pci_dev *pdev)
         u16 control = 0;
         int pos;
 
-        pos = pci_find_ext_capability(pdev, PCI_PASID_CAP);
+        pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID);
         if (!pos)
                 return;
 
-        pci_write_config_word(pdev, pos + PCI_PASID_CONTROL_OFF, control);
+        pci_write_config_word(pdev, pos + PCI_PASID_CTRL, control);
 }
 EXPORT_SYMBOL_GPL(pci_disable_pasid);
 
@@ -390,22 +391,21 @@ EXPORT_SYMBOL_GPL(pci_disable_pasid);
  * Returns a negative value when no PASI capability is present.
  * Otherwise is returns a bitmask with supported features. Current
  * features reported are:
- * PCI_PASID_ENABLE - PASID capability can be enabled
- * PCI_PASID_EXEC - Execute permission supported
- * PCI_PASID_PRIV - Priviledged mode supported
+ * PCI_PASID_CAP_EXEC - Execute permission supported
+ * PCI_PASID_CAP_PRIV - Priviledged mode supported
  */
 int pci_pasid_features(struct pci_dev *pdev)
 {
         u16 supported;
         int pos;
 
-        pos = pci_find_ext_capability(pdev, PCI_PASID_CAP);
+        pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID);
         if (!pos)
                 return -EINVAL;
 
-        pci_read_config_word(pdev, pos + PCI_PASID_CAP_OFF, &supported);
+        pci_read_config_word(pdev, pos + PCI_PASID_CAP, &supported);
 
-        supported &= PCI_PASID_ENABLE | PCI_PASID_EXEC | PCI_PASID_PRIV;
+        supported &= PCI_PASID_CAP_EXEC | PCI_PASID_CAP_PRIV;
 
         return supported;
 }
@@ -425,11 +425,11 @@ int pci_max_pasids(struct pci_dev *pdev)
         u16 supported;
         int pos;
 
-        pos = pci_find_ext_capability(pdev, PCI_PASID_CAP);
+        pos = pci_find_ext_capability(pdev, PCI_EXT_CAP_ID_PASID);
         if (!pos)
                 return -EINVAL;
 
-        pci_read_config_word(pdev, pos + PCI_PASID_CAP_OFF, &supported);
+        pci_read_config_word(pdev, pos + PCI_PASID_CAP, &supported);
 
         supported = (supported & PASID_NUMBER_MASK) >> PASID_NUMBER_SHIFT;
 
diff --git a/drivers/pci/hotplug/acpiphp_glue.c b/drivers/pci/hotplug/acpiphp_glue.c
index fce1c54a0c8d..ba43c037de80 100644
--- a/drivers/pci/hotplug/acpiphp_glue.c
+++ b/drivers/pci/hotplug/acpiphp_glue.c
@@ -467,7 +467,7 @@ static int add_bridge(acpi_handle handle)
          * granted by the BIOS for it.
          */
         root = acpi_pci_find_root(handle);
-        if (root && (root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL))
+        if (root && (root->osc_control_set & OSC_PCI_NATIVE_HOTPLUG))
                 return -ENODEV;
 
         /* if the bridge doesn't have _STA, we assume it is always there */
@@ -1395,7 +1395,7 @@ find_root_bridges(acpi_handle handle, u32 lvl, void *context, void **rv)
         if (!root)
                 return AE_OK;
 
-        if (root->osc_control_set & OSC_PCI_EXPRESS_NATIVE_HP_CONTROL)
+        if (root->osc_control_set & OSC_PCI_NATIVE_HOTPLUG)
                 return AE_OK;
 
         (*count)++;
diff --git a/drivers/pci/hotplug/pciehp.h b/drivers/pci/hotplug/pciehp.h
index 838f571027b7..9a33fdde2d16 100644
--- a/drivers/pci/hotplug/pciehp.h
+++ b/drivers/pci/hotplug/pciehp.h
@@ -45,7 +45,6 @@ extern int pciehp_poll_time;
 extern int pciehp_debug;
 extern int pciehp_force;
 extern struct workqueue_struct *pciehp_wq;
-extern struct workqueue_struct *pciehp_ordered_wq;
 
 #define dbg(format, arg...)                                             \
 do {                                                                    \
diff --git a/drivers/pci/hotplug/pciehp_core.c b/drivers/pci/hotplug/pciehp_core.c
index 7ac8358df8fd..b8c99d35ac97 100644
--- a/drivers/pci/hotplug/pciehp_core.c
+++ b/drivers/pci/hotplug/pciehp_core.c
@@ -43,7 +43,6 @@ int pciehp_poll_mode;
 int pciehp_poll_time;
 int pciehp_force;
 struct workqueue_struct *pciehp_wq;
-struct workqueue_struct *pciehp_ordered_wq;
 
 #define DRIVER_VERSION  "0.4"
 #define DRIVER_AUTHOR   "Dan Zink <dan.zink@compaq.com>, Greg Kroah-Hartman <greg@kroah.com>, Dely Sy <dely.l.sy@intel.com>"
@@ -345,18 +344,11 @@ static int __init pcied_init(void)
         if (!pciehp_wq)
                 return -ENOMEM;
 
-        pciehp_ordered_wq = alloc_ordered_workqueue("pciehp_ordered", 0);
-        if (!pciehp_ordered_wq) {
-                destroy_workqueue(pciehp_wq);
-                return -ENOMEM;
-        }
-
         pciehp_firmware_init();
         retval = pcie_port_service_register(&hpdriver_portdrv);
         dbg("pcie_port_service_register = %d\n", retval);
         info(DRIVER_DESC " version: " DRIVER_VERSION "\n");
         if (retval) {
-                destroy_workqueue(pciehp_ordered_wq);
                 destroy_workqueue(pciehp_wq);
                 dbg("Failure to register service\n");
         }
@@ -366,9 +358,8 @@ static int __init pcied_init(void)
 static void __exit pcied_cleanup(void)
 {
         dbg("unload_pciehpd()\n");
-        destroy_workqueue(pciehp_ordered_wq);
-        destroy_workqueue(pciehp_wq);
         pcie_port_service_unregister(&hpdriver_portdrv);
+        destroy_workqueue(pciehp_wq);
         info(DRIVER_DESC " version: " DRIVER_VERSION " unloaded\n");
 }
 
diff --git a/drivers/pci/hotplug/pciehp_ctrl.c b/drivers/pci/hotplug/pciehp_ctrl.c
index 085dbb5fc168..27f44295a657 100644
--- a/drivers/pci/hotplug/pciehp_ctrl.c
+++ b/drivers/pci/hotplug/pciehp_ctrl.c
@@ -344,7 +344,7 @@ void pciehp_queue_pushbutton_work(struct work_struct *work)
                 kfree(info);
                 goto out;
         }
-        queue_work(pciehp_ordered_wq, &info->work);
+        queue_work(pciehp_wq, &info->work);
  out:
         mutex_unlock(&p_slot->lock);
 }
@@ -439,7 +439,7 @@ static void handle_surprise_event(struct slot *p_slot)
         else
                 p_slot->state = POWERON_STATE;
 
-        queue_work(pciehp_ordered_wq, &info->work);
+        queue_work(pciehp_wq, &info->work);
 }
 
 static void interrupt_event_handler(struct work_struct *work)
diff --git a/drivers/pci/hotplug/pciehp_hpc.c b/drivers/pci/hotplug/pciehp_hpc.c
index 7b1414810ae3..bcdbb1643621 100644
--- a/drivers/pci/hotplug/pciehp_hpc.c
+++ b/drivers/pci/hotplug/pciehp_hpc.c
@@ -806,7 +806,6 @@ static void pcie_cleanup_slot(struct controller *ctrl)
         struct slot *slot = ctrl->slot;
         cancel_delayed_work(&slot->work);
         flush_workqueue(pciehp_wq);
-        flush_workqueue(pciehp_ordered_wq);
         kfree(slot);
 }
 
diff --git a/drivers/pci/msi.c b/drivers/pci/msi.c
index 0e6d04d7ba4f..337e16ab4a92 100644
--- a/drivers/pci/msi.c
+++ b/drivers/pci/msi.c
@@ -323,6 +323,8 @@ static void free_msi_irqs(struct pci_dev *dev)
                         if (list_is_last(&entry->list, &dev->msi_list))
                                 iounmap(entry->mask_base);
                 }
+                kobject_del(&entry->kobj);
+                kobject_put(&entry->kobj);
                 list_del(&entry->list);
                 kfree(entry);
         }
@@ -403,6 +405,98 @@ void pci_restore_msi_state(struct pci_dev *dev)
 }
 EXPORT_SYMBOL_GPL(pci_restore_msi_state);
 
+
+#define to_msi_attr(obj) container_of(obj, struct msi_attribute, attr)
+#define to_msi_desc(obj) container_of(obj, struct msi_desc, kobj)
+
+struct msi_attribute {
+        struct attribute        attr;
+        ssize_t (*show)(struct msi_desc *entry, struct msi_attribute *attr,
+                        char *buf);
+        ssize_t (*store)(struct msi_desc *entry, struct msi_attribute *attr,
+                         const char *buf, size_t count);
+};
+
+static ssize_t show_msi_mode(struct msi_desc *entry, struct msi_attribute *atr,
+                             char *buf)
+{
+        return sprintf(buf, "%s\n", entry->msi_attrib.is_msix ? "msix" : "msi");
+}
+
+static ssize_t msi_irq_attr_show(struct kobject *kobj,
+                                 struct attribute *attr, char *buf)
+{
+        struct msi_attribute *attribute = to_msi_attr(attr);
+        struct msi_desc *entry = to_msi_desc(kobj);
+
+        if (!attribute->show)
+                return -EIO;
+
+        return attribute->show(entry, attribute, buf);
+}
+
+static const struct sysfs_ops msi_irq_sysfs_ops = {
+        .show = msi_irq_attr_show,
+};
+
+static struct msi_attribute mode_attribute =
+        __ATTR(mode, S_IRUGO, show_msi_mode, NULL);
+
+
+struct attribute *msi_irq_default_attrs[] = {
+        &mode_attribute.attr,
+        NULL
+};
+
+void msi_kobj_release(struct kobject *kobj)
+{
+        struct msi_desc *entry = to_msi_desc(kobj);
+
+        pci_dev_put(entry->dev);
+}
+
+static struct kobj_type msi_irq_ktype = {
+        .release = msi_kobj_release,
+        .sysfs_ops = &msi_irq_sysfs_ops,
+        .default_attrs = msi_irq_default_attrs,
+};
+
+static int populate_msi_sysfs(struct pci_dev *pdev)
+{
+        struct msi_desc *entry;
+        struct kobject *kobj;
+        int ret;
+        int count = 0;
+
+        pdev->msi_kset = kset_create_and_add("msi_irqs", NULL, &pdev->dev.kobj);
+        if (!pdev->msi_kset)
+                return -ENOMEM;
+
+        list_for_each_entry(entry, &pdev->msi_list, list) {
+                kobj = &entry->kobj;
+                kobj->kset = pdev->msi_kset;
+                pci_dev_get(pdev);
+                ret = kobject_init_and_add(kobj, &msi_irq_ktype, NULL,
+                                     "%u", entry->irq);
+                if (ret)
+                        goto out_unroll;
+
+                count++;
+        }
+
+        return 0;
+
+out_unroll:
+        list_for_each_entry(entry, &pdev->msi_list, list) {
+                if (!count)
+                        break;
+                kobject_del(&entry->kobj);
+                kobject_put(&entry->kobj);
+                count--;
+        }
+        return ret;
+}
+
 /**
  * msi_capability_init - configure device's MSI capability structure
  * @dev: pointer to the pci_dev data structure of MSI device function
@@ -454,6 +548,13 @@ static int msi_capability_init(struct pci_dev *dev, int nvec)
                 return ret;
         }
 
+        ret = populate_msi_sysfs(dev);
+        if (ret) {
+                msi_mask_irq(entry, mask, ~mask);
+                free_msi_irqs(dev);
+                return ret;
+        }
+
         /* Set MSI enabled bits  */
         pci_intx_for_msi(dev, 0);
         msi_set_enable(dev, pos, 1);
@@ -574,6 +675,12 @@ static int msix_capability_init(struct pci_dev *dev,
 
         msix_program_entries(dev, entries);
 
+        ret = populate_msi_sysfs(dev);
+        if (ret) {
+                ret = 0;
+                goto error;
+        }
+
         /* Set MSI-X enabled bits and unmask the function */
         pci_intx_for_msi(dev, 0);
         dev->msix_enabled = 1;
@@ -732,6 +839,8 @@ void pci_disable_msi(struct pci_dev *dev)
 
         pci_msi_shutdown(dev);
         free_msi_irqs(dev);
+        kset_unregister(dev->msi_kset);
+        dev->msi_kset = NULL;
 }
 EXPORT_SYMBOL(pci_disable_msi);
 
@@ -830,6 +939,8 @@ void pci_disable_msix(struct pci_dev *dev)
 
         pci_msix_shutdown(dev);
         free_msi_irqs(dev);
+        kset_unregister(dev->msi_kset);
+        dev->msi_kset = NULL;
 }
 EXPORT_SYMBOL(pci_disable_msix);
 
@@ -870,5 +981,15 @@ EXPORT_SYMBOL(pci_msi_enabled);
 
 void pci_msi_init_pci_dev(struct pci_dev *dev)
 {
+        int pos;
         INIT_LIST_HEAD(&dev->msi_list);
+
+        /* Disable the msi hardware to avoid screaming interrupts
+         * during boot.  This is the power on reset default so
+         * usually this should be a noop.
+         */
+        pos = pci_find_capability(dev, PCI_CAP_ID_MSI);
+        if (pos)
+                msi_set_enable(dev, pos, 0);
+        msix_set_enable(dev, 0);
 }
diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index 4ecb6408b0d6..060fd22a1103 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -45,16 +45,20 @@ static void pci_acpi_wake_dev(acpi_handle handle, u32 event, void *context)
 {
         struct pci_dev *pci_dev = context;
 
-        if (event == ACPI_NOTIFY_DEVICE_WAKE && pci_dev) {
+        if (event != ACPI_NOTIFY_DEVICE_WAKE || !pci_dev)
+                return;
+
+        if (!pci_dev->pm_cap || !pci_dev->pme_support
+             || pci_check_pme_status(pci_dev)) {
                 if (pci_dev->pme_poll)
                         pci_dev->pme_poll = false;
 
                 pci_wakeup_event(pci_dev);
-                pci_check_pme_status(pci_dev);
                 pm_runtime_resume(&pci_dev->dev);
-                if (pci_dev->subordinate)
-                        pci_pme_wakeup_bus(pci_dev->subordinate);
         }
+
+        if (pci_dev->subordinate)
+                pci_pme_wakeup_bus(pci_dev->subordinate);
 }
 
 /**
@@ -395,7 +399,6 @@ static int __init acpi_pci_init(void)
 
         if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
                 printk(KERN_INFO"ACPI FADT declares the system doesn't support PCIe ASPM, so disable it\n");
-                pcie_clear_aspm();
                 pcie_no_aspm();
         }
 
diff --git a/drivers/pci/pcie/aspm.c b/drivers/pci/pcie/aspm.c
index cbfbab18be91..1cfbf228fbb1 100644
--- a/drivers/pci/pcie/aspm.c
+++ b/drivers/pci/pcie/aspm.c
@@ -68,7 +68,7 @@ struct pcie_link_state {
         struct aspm_latency acceptable[8];
 };
 
-static int aspm_disabled, aspm_force, aspm_clear_state;
+static int aspm_disabled, aspm_force;
 static bool aspm_support_enabled = true;
 static DEFINE_MUTEX(aspm_lock);
 static LIST_HEAD(link_list);
@@ -500,9 +500,6 @@ static int pcie_aspm_sanity_check(struct pci_dev *pdev)
         int pos;
         u32 reg32;
 
-        if (aspm_clear_state)
-                return -EINVAL;
-
         /*
          * Some functions in a slot might not all be PCIe functions,
          * very strange. Disable ASPM for the whole slot
@@ -574,9 +571,6 @@ void pcie_aspm_init_link_state(struct pci_dev *pdev)
             pdev->pcie_type != PCI_EXP_TYPE_DOWNSTREAM)
                 return;
 
-        if (aspm_disabled && !aspm_clear_state)
-                return;
-
         /* VIA has a strange chipset, root port is under a bridge */
         if (pdev->pcie_type == PCI_EXP_TYPE_ROOT_PORT &&
             pdev->bus->self)
@@ -608,7 +602,7 @@ void pcie_aspm_init_link_state(struct pci_dev *pdev)
          * the BIOS's expectation, we'll do so once pci_enable_device() is
          * called.
          */
-        if (aspm_policy != POLICY_POWERSAVE || aspm_clear_state) {
+        if (aspm_policy != POLICY_POWERSAVE) {
                 pcie_config_aspm_path(link);
                 pcie_set_clkpm(link, policy_to_clkpm_state(link));
         }
@@ -649,8 +643,7 @@ void pcie_aspm_exit_link_state(struct pci_dev *pdev)
         struct pci_dev *parent = pdev->bus->self;
         struct pcie_link_state *link, *root, *parent_link;
 
-        if ((aspm_disabled && !aspm_clear_state) || !pci_is_pcie(pdev) ||
-            !parent || !parent->link_state)
+        if (!pci_is_pcie(pdev) || !parent || !parent->link_state)
                 return;
         if ((parent->pcie_type != PCI_EXP_TYPE_ROOT_PORT) &&
             (parent->pcie_type != PCI_EXP_TYPE_DOWNSTREAM))
@@ -734,13 +727,18 @@ void pcie_aspm_powersave_config_link(struct pci_dev *pdev)
  * pci_disable_link_state - disable pci device's link state, so the link will
  * never enter specific states
  */
-static void __pci_disable_link_state(struct pci_dev *pdev, int state, bool sem)
+static void __pci_disable_link_state(struct pci_dev *pdev, int state, bool sem,
+                                     bool force)
 {
         struct pci_dev *parent = pdev->bus->self;
         struct pcie_link_state *link;
 
-        if (aspm_disabled || !pci_is_pcie(pdev))
+        if (aspm_disabled && !force)
+                return;
+
+        if (!pci_is_pcie(pdev))
                 return;
+
         if (pdev->pcie_type == PCI_EXP_TYPE_ROOT_PORT ||
             pdev->pcie_type == PCI_EXP_TYPE_DOWNSTREAM)
                 parent = pdev;
@@ -768,16 +766,31 @@ static void __pci_disable_link_state(struct pci_dev *pdev, int state, bool sem)
 
 void pci_disable_link_state_locked(struct pci_dev *pdev, int state)
 {
-        __pci_disable_link_state(pdev, state, false);
+        __pci_disable_link_state(pdev, state, false, false);
 }
 EXPORT_SYMBOL(pci_disable_link_state_locked);
 
 void pci_disable_link_state(struct pci_dev *pdev, int state)
 {
-        __pci_disable_link_state(pdev, state, true);
+        __pci_disable_link_state(pdev, state, true, false);
 }
 EXPORT_SYMBOL(pci_disable_link_state);
 
+void pcie_clear_aspm(struct pci_bus *bus)
+{
+        struct pci_dev *child;
+
+        /*
+         * 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;
@@ -935,6 +948,7 @@ void pcie_aspm_remove_sysfs_dev_files(struct pci_dev *pdev)
 static int __init pcie_aspm_disable(char *str)
 {
         if (!strcmp(str, "off")) {
+                aspm_policy = POLICY_DEFAULT;
                 aspm_disabled = 1;
                 aspm_support_enabled = false;
                 printk(KERN_INFO "PCIe ASPM is disabled\n");
@@ -947,16 +961,18 @@ static int __init pcie_aspm_disable(char *str)
 
 __setup("pcie_aspm=", pcie_aspm_disable);
 
-void pcie_clear_aspm(void)
-{
-        if (!aspm_force)
-                aspm_clear_state = 1;
-}
-
 void pcie_no_aspm(void)
 {
-        if (!aspm_force)
+        /*
+         * Disabling ASPM is intended to prevent the kernel from modifying
+         * existing hardware state, not to clear existing state. To that end:
+         * (a) set policy to POLICY_DEFAULT in order to avoid changing state
+         * (b) prevent userspace from changing policy
+         */
+        if (!aspm_force) {
+                aspm_policy = POLICY_DEFAULT;
                 aspm_disabled = 1;
+        }
 }
 
 /**