12 files changed, 118 insertions, 56 deletions

diff --git a/Documentation/PCI/pci.txt b/Documentation/PCI/pci.txt
index 9518006f6675..123881f62219 100644
--- a/Documentation/PCI/pci.txt
+++ b/Documentation/PCI/pci.txt
@@ -564,14 +564,14 @@ to be handled by platform and generic code, not individual drivers.
 8. Vendor and device identifications
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-One is not required to add new device ids to include/linux/pci_ids.h.
-Please add PCI_VENDOR_ID_xxx for vendors and a hex constant for device ids.
+Do not add new device or vendor IDs to include/linux/pci_ids.h unless they
+are shared across multiple drivers.  You can add private definitions in
+your driver if they're helpful, or just use plain hex constants.
 
-PCI_VENDOR_ID_xxx constants are re-used. The device ids are arbitrary
-hex numbers (vendor controlled) and normally used only in a single
-location, the pci_device_id table.
+The device IDs are arbitrary hex numbers (vendor controlled) and normally used
+only in a single location, the pci_device_id table.
 
-Please DO submit new vendor/device ids to pciids.sourceforge.net project.
+Please DO submit new vendor/device IDs to http://pciids.sourceforge.net/.
 
 
 
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/host-bridge.c b/drivers/pci/host-bridge.c
index 3e5bbf9e8889..5f4a2e04c8d7 100644
--- a/drivers/pci/host-bridge.c
+++ b/drivers/pci/host-bridge.c
@@ -16,7 +16,7 @@ static struct pci_bus *find_pci_root_bus(struct pci_bus *bus)
         return bus;
 }
 
-static struct pci_host_bridge *find_pci_host_bridge(struct pci_bus *bus)
+struct pci_host_bridge *pci_find_host_bridge(struct pci_bus *bus)
 {
         struct pci_bus *root_bus = find_pci_root_bus(bus);
 
@@ -48,7 +48,7 @@ void pci_set_host_bridge_release(struct pci_host_bridge *bridge,
 void pcibios_resource_to_bus(struct pci_bus *bus, struct pci_bus_region *region,
                              struct resource *res)
 {
-        struct pci_host_bridge *bridge = find_pci_host_bridge(bus);
+        struct pci_host_bridge *bridge = pci_find_host_bridge(bus);
         struct resource_entry *window;
         resource_size_t offset = 0;
 
@@ -73,7 +73,7 @@ static bool region_contains(struct pci_bus_region *region1,
 void pcibios_bus_to_resource(struct pci_bus *bus, struct resource *res,
                              struct pci_bus_region *region)
 {
-        struct pci_host_bridge *bridge = find_pci_host_bridge(bus);
+        struct pci_host_bridge *bridge = pci_find_host_bridge(bus);
         struct resource_entry *window;
         resource_size_t offset = 0;
 
diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
index 489063987325..5eba74716900 100644
--- a/drivers/pci/pci-acpi.c
+++ b/drivers/pci/pci-acpi.c
@@ -18,6 +18,15 @@
 #include <linux/pm_qos.h>
 #include "pci.h"
 
+/*
+ * The UUID is defined in the PCI Firmware Specification available here:
+ * https://www.pcisig.com/members/downloads/pcifw_r3_1_13Dec10.pdf
+ */
+const u8 pci_acpi_dsm_uuid[] = {
+        0xd0, 0x37, 0xc9, 0xe5, 0x53, 0x35, 0x7a, 0x4d,
+        0x91, 0x17, 0xea, 0x4d, 0x19, 0xc3, 0x43, 0x4d
+};
+
 phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle)
 {
         acpi_status status = AE_NOT_EXIST;
@@ -528,11 +537,32 @@ static struct pci_platform_pm_ops acpi_pci_platform_pm = {
 
 void acpi_pci_add_bus(struct pci_bus *bus)
 {
+        union acpi_object *obj;
+        struct pci_host_bridge *bridge;
+
         if (acpi_pci_disabled || !bus->bridge)
                 return;
 
         acpi_pci_slot_enumerate(bus);
         acpiphp_enumerate_slots(bus);
+
+        /*
+         * For a host bridge, check its _DSM for function 8 and if
+         * that is available, mark it in pci_host_bridge.
+         */
+        if (!pci_is_root_bus(bus))
+                return;
+
+        obj = acpi_evaluate_dsm(ACPI_HANDLE(bus->bridge), pci_acpi_dsm_uuid, 3,
+                                RESET_DELAY_DSM, NULL);
+        if (!obj)
+                return;
+
+        if (obj->type == ACPI_TYPE_INTEGER && obj->integer.value == 1) {
+                bridge = pci_find_host_bridge(bus);
+                bridge->ignore_reset_delay = 1;
+        }
+        ACPI_FREE(obj);
 }
 
 void acpi_pci_remove_bus(struct pci_bus *bus)
@@ -558,6 +588,57 @@ static struct acpi_device *acpi_pci_find_companion(struct device *dev)
                                       check_children);
 }
 
+/**
+ * pci_acpi_optimize_delay - optimize PCI D3 and D3cold delay from ACPI
+ * @pdev: the PCI device whose delay is to be updated
+ * @adev: the companion ACPI device of this PCI device
+ *
+ * Update the d3_delay and d3cold_delay of a PCI device from the ACPI _DSM
+ * control method of either the device itself or the PCI host bridge.
+ *
+ * Function 8, "Reset Delay," applies to the entire hierarchy below a PCI
+ * host bridge.  If it returns one, the OS may assume that all devices in
+ * the hierarchy have already completed power-on reset delays.
+ *
+ * Function 9, "Device Readiness Durations," applies only to the object
+ * where it is located.  It returns delay durations required after various
+ * events if the device requires less time than the spec requires.  Delays
+ * from this function take precedence over the Reset Delay function.
+ *
+ * These _DSM functions are defined by the draft ECN of January 28, 2014,
+ * titled "ACPI additions for FW latency optimizations."
+ */
+static void pci_acpi_optimize_delay(struct pci_dev *pdev,
+                                    acpi_handle handle)
+{
+        struct pci_host_bridge *bridge = pci_find_host_bridge(pdev->bus);
+        int value;
+        union acpi_object *obj, *elements;
+
+        if (bridge->ignore_reset_delay)
+                pdev->d3cold_delay = 0;
+
+        obj = acpi_evaluate_dsm(handle, pci_acpi_dsm_uuid, 3,
+                                FUNCTION_DELAY_DSM, NULL);
+        if (!obj)
+                return;
+
+        if (obj->type == ACPI_TYPE_PACKAGE && obj->package.count == 5) {
+                elements = obj->package.elements;
+                if (elements[0].type == ACPI_TYPE_INTEGER) {
+                        value = (int)elements[0].integer.value / 1000;
+                        if (value < PCI_PM_D3COLD_WAIT)
+                                pdev->d3cold_delay = value;
+                }
+                if (elements[3].type == ACPI_TYPE_INTEGER) {
+                        value = (int)elements[3].integer.value / 1000;
+                        if (value < PCI_PM_D3_WAIT)
+                                pdev->d3_delay = value;
+                }
+        }
+        ACPI_FREE(obj);
+}
+
 static void pci_acpi_setup(struct device *dev)
 {
         struct pci_dev *pci_dev = to_pci_dev(dev);
@@ -566,6 +647,8 @@ static void pci_acpi_setup(struct device *dev)
         if (!adev)
                 return;
 
+        pci_acpi_optimize_delay(pci_dev, adev->handle);
+
         pci_acpi_add_pm_notifier(adev, pci_dev);
         if (!adev->wakeup.flags.valid)
                 return;
diff --git a/drivers/pci/pci-label.c b/drivers/pci/pci-label.c
index 2ab1b47c7651..024b5c179348 100644
--- a/drivers/pci/pci-label.c
+++ b/drivers/pci/pci-label.c
@@ -31,8 +31,6 @@
 #include <linux/pci-acpi.h>
 #include "pci.h"
 
-#define DEVICE_LABEL_DSM        0x07
-
 #ifdef CONFIG_DMI
 enum smbios_attr_enum {
         SMBIOS_ATTR_NONE = 0,
@@ -148,11 +146,6 @@ static inline void pci_remove_smbiosname_file(struct pci_dev *pdev)
 #endif
 
 #ifdef CONFIG_ACPI
-static const char device_label_dsm_uuid[] = {
-        0xD0, 0x37, 0xC9, 0xE5, 0x53, 0x35, 0x7A, 0x4D,
-        0x91, 0x17, 0xEA, 0x4D, 0x19, 0xC3, 0x43, 0x4D
-};
-
 enum acpi_attr_enum {
         ACPI_ATTR_LABEL_SHOW,
         ACPI_ATTR_INDEX_SHOW,
@@ -179,7 +172,7 @@ static int dsm_get_label(struct device *dev, char *buf,
         if (!handle)
                 return -1;
 
-        obj = acpi_evaluate_dsm(handle, device_label_dsm_uuid, 0x2,
+        obj = acpi_evaluate_dsm(handle, pci_acpi_dsm_uuid, 0x2,
                                 DEVICE_LABEL_DSM, NULL);
         if (!obj)
                 return -1;
@@ -219,7 +212,7 @@ static bool device_has_dsm(struct device *dev)
         if (!handle)
                 return false;
 
-        return !!acpi_check_dsm(handle, device_label_dsm_uuid, 0x2,
+        return !!acpi_check_dsm(handle, pci_acpi_dsm_uuid, 0x2,
                                 1 << DEVICE_LABEL_DSM);
 }
 
diff --git a/drivers/pci/pci.c b/drivers/pci/pci.c
index 061fdce8f8e1..acc4b6ef78c4 100644
--- a/drivers/pci/pci.c
+++ b/drivers/pci/pci.c
@@ -146,19 +146,22 @@ static int __pci_find_next_cap_ttl(struct pci_bus *bus, unsigned int devfn,
                                    u8 pos, int cap, int *ttl)
 {
         u8 id;
+        u16 ent;
+
+        pci_bus_read_config_byte(bus, devfn, pos, &pos);
 
         while ((*ttl)--) {
-                pci_bus_read_config_byte(bus, devfn, pos, &pos);
                 if (pos < 0x40)
                         break;
                 pos &= ~3;
-                pci_bus_read_config_byte(bus, devfn, pos + PCI_CAP_LIST_ID,
-                                         &id);
+                pci_bus_read_config_word(bus, devfn, pos, &ent);
+
+                id = ent & 0xff;
                 if (id == 0xff)
                         break;
                 if (id == cap)
                         return pos;
-                pos += PCI_CAP_LIST_NEXT;
+                pos = (ent >> 8);
         }
         return 0;
 }
diff --git a/drivers/pci/pci.h b/drivers/pci/pci.h
index 4091f82239cd..d72f849174a4 100644
--- a/drivers/pci/pci.h
+++ b/drivers/pci/pci.h
@@ -321,4 +321,6 @@ static inline int pci_dev_specific_reset(struct pci_dev *dev, int probe)
 }
 #endif
 
+struct pci_host_bridge *pci_find_host_bridge(struct pci_bus *bus);
+
 #endif /* DRIVERS_PCI_H */
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/drivers/pci/quirks.c b/drivers/pci/quirks.c
index 1bde3972e318..c6dc1dfd25d5 100644
--- a/drivers/pci/quirks.c
+++ b/drivers/pci/quirks.c
@@ -3182,7 +3182,7 @@ static void quirk_apple_wait_for_thunderbolt(struct pci_dev *dev)
                         || nhi->subsystem_vendor != 0x2222
                         || nhi->subsystem_device != 0x1111)
                 goto out;
-        dev_info(&dev->dev, "quirk: wating for thunderbolt to reestablish pci tunnels...\n");
+        dev_info(&dev->dev, "quirk: waiting for thunderbolt to reestablish PCI tunnels...\n");
         device_pm_wait_for_dev(&dev->dev, &nhi->dev);
 out:
         pci_dev_put(nhi);
diff --git a/include/linux/pci-acpi.h b/include/linux/pci-acpi.h
index 24c7728ca681..a965efa52152 100644
--- a/include/linux/pci-acpi.h
+++ b/include/linux/pci-acpi.h
@@ -77,6 +77,11 @@ static inline void acpiphp_remove_slots(struct pci_bus *bus) { }
 static inline void acpiphp_check_host_bridge(struct acpi_device *adev) { }
 #endif
 
+extern const u8 pci_acpi_dsm_uuid[];
+#define DEVICE_LABEL_DSM        0x07
+#define RESET_DELAY_DSM         0x08
+#define FUNCTION_DELAY_DSM      0x09
+
 #else   /* CONFIG_ACPI */
 static inline void acpi_pci_add_bus(struct pci_bus *bus) { }
 static inline void acpi_pci_remove_bus(struct pci_bus *bus) { }
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)
 {
 }
diff --git a/include/linux/pci.h b/include/linux/pci.h
index a379513bddef..e63112fb55be 100644
--- a/include/linux/pci.h
+++ b/include/linux/pci.h
@@ -406,6 +406,7 @@ struct pci_host_bridge {
         struct list_head windows;       /* resource_entry */
         void (*release_fn)(struct pci_host_bridge *);
         void *release_data;
+        unsigned int ignore_reset_delay:1;      /* for entire hierarchy */
 };
 
 #define to_pci_host_bridge(n) container_of(n, struct pci_host_bridge, dev)