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-rw-r--r--drivers/pci/pci-acpi.c405
1 files changed, 405 insertions, 0 deletions
diff --git a/drivers/pci/pci-acpi.c b/drivers/pci/pci-acpi.c
new file mode 100644
index 00000000..56b04bc8
--- /dev/null
+++ b/drivers/pci/pci-acpi.c
@@ -0,0 +1,405 @@
+/*
+ * File: pci-acpi.c
+ * Purpose: Provide PCI support in ACPI
+ *
+ * Copyright (C) 2005 David Shaohua Li <shaohua.li@intel.com>
+ * Copyright (C) 2004 Tom Long Nguyen <tom.l.nguyen@intel.com>
+ * Copyright (C) 2004 Intel Corp.
+ */
+
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/pci.h>
+#include <linux/module.h>
+#include <linux/pci-aspm.h>
+#include <acpi/acpi.h>
+#include <acpi/acpi_bus.h>
+
+#include <linux/pci-acpi.h>
+#include <linux/pm_runtime.h>
+#include "pci.h"
+
+static DEFINE_MUTEX(pci_acpi_pm_notify_mtx);
+
+/**
+ * pci_acpi_wake_bus - Wake-up notification handler for root buses.
+ * @handle: ACPI handle of a device the notification is for.
+ * @event: Type of the signaled event.
+ * @context: PCI root bus to wake up devices on.
+ */
+static void pci_acpi_wake_bus(acpi_handle handle, u32 event, void *context)
+{
+ struct pci_bus *pci_bus = context;
+
+ if (event == ACPI_NOTIFY_DEVICE_WAKE && pci_bus)
+ pci_pme_wakeup_bus(pci_bus);
+}
+
+/**
+ * pci_acpi_wake_dev - Wake-up notification handler for PCI devices.
+ * @handle: ACPI handle of a device the notification is for.
+ * @event: Type of the signaled event.
+ * @context: PCI device object to wake up.
+ */
+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) {
+ 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);
+ }
+}
+
+/**
+ * add_pm_notifier - Register PM notifier for given ACPI device.
+ * @dev: ACPI device to add the notifier for.
+ * @context: PCI device or bus to check for PME status if an event is signaled.
+ *
+ * NOTE: @dev need not be a run-wake or wake-up device to be a valid source of
+ * PM wake-up events. For example, wake-up events may be generated for bridges
+ * if one of the devices below the bridge is signaling PME, even if the bridge
+ * itself doesn't have a wake-up GPE associated with it.
+ */
+static acpi_status add_pm_notifier(struct acpi_device *dev,
+ acpi_notify_handler handler,
+ void *context)
+{
+ acpi_status status = AE_ALREADY_EXISTS;
+
+ mutex_lock(&pci_acpi_pm_notify_mtx);
+
+ if (dev->wakeup.flags.notifier_present)
+ goto out;
+
+ status = acpi_install_notify_handler(dev->handle,
+ ACPI_SYSTEM_NOTIFY,
+ handler, context);
+ if (ACPI_FAILURE(status))
+ goto out;
+
+ dev->wakeup.flags.notifier_present = true;
+
+ out:
+ mutex_unlock(&pci_acpi_pm_notify_mtx);
+ return status;
+}
+
+/**
+ * remove_pm_notifier - Unregister PM notifier from given ACPI device.
+ * @dev: ACPI device to remove the notifier from.
+ */
+static acpi_status remove_pm_notifier(struct acpi_device *dev,
+ acpi_notify_handler handler)
+{
+ acpi_status status = AE_BAD_PARAMETER;
+
+ mutex_lock(&pci_acpi_pm_notify_mtx);
+
+ if (!dev->wakeup.flags.notifier_present)
+ goto out;
+
+ status = acpi_remove_notify_handler(dev->handle,
+ ACPI_SYSTEM_NOTIFY,
+ handler);
+ if (ACPI_FAILURE(status))
+ goto out;
+
+ dev->wakeup.flags.notifier_present = false;
+
+ out:
+ mutex_unlock(&pci_acpi_pm_notify_mtx);
+ return status;
+}
+
+/**
+ * pci_acpi_add_bus_pm_notifier - Register PM notifier for given PCI bus.
+ * @dev: ACPI device to add the notifier for.
+ * @pci_bus: PCI bus to walk checking for PME status if an event is signaled.
+ */
+acpi_status pci_acpi_add_bus_pm_notifier(struct acpi_device *dev,
+ struct pci_bus *pci_bus)
+{
+ return add_pm_notifier(dev, pci_acpi_wake_bus, pci_bus);
+}
+
+/**
+ * pci_acpi_remove_bus_pm_notifier - Unregister PCI bus PM notifier.
+ * @dev: ACPI device to remove the notifier from.
+ */
+acpi_status pci_acpi_remove_bus_pm_notifier(struct acpi_device *dev)
+{
+ return remove_pm_notifier(dev, pci_acpi_wake_bus);
+}
+
+/**
+ * pci_acpi_add_pm_notifier - Register PM notifier for given PCI device.
+ * @dev: ACPI device to add the notifier for.
+ * @pci_dev: PCI device to check for the PME status if an event is signaled.
+ */
+acpi_status pci_acpi_add_pm_notifier(struct acpi_device *dev,
+ struct pci_dev *pci_dev)
+{
+ return add_pm_notifier(dev, pci_acpi_wake_dev, pci_dev);
+}
+
+/**
+ * pci_acpi_remove_pm_notifier - Unregister PCI device PM notifier.
+ * @dev: ACPI device to remove the notifier from.
+ */
+acpi_status pci_acpi_remove_pm_notifier(struct acpi_device *dev)
+{
+ return remove_pm_notifier(dev, pci_acpi_wake_dev);
+}
+
+/*
+ * _SxD returns the D-state with the highest power
+ * (lowest D-state number) supported in the S-state "x".
+ *
+ * If the devices does not have a _PRW
+ * (Power Resources for Wake) supporting system wakeup from "x"
+ * then the OS is free to choose a lower power (higher number
+ * D-state) than the return value from _SxD.
+ *
+ * But if _PRW is enabled at S-state "x", the OS
+ * must not choose a power lower than _SxD --
+ * unless the device has an _SxW method specifying
+ * the lowest power (highest D-state number) the device
+ * may enter while still able to wake the system.
+ *
+ * ie. depending on global OS policy:
+ *
+ * if (_PRW at S-state x)
+ * choose from highest power _SxD to lowest power _SxW
+ * else // no _PRW at S-state x
+ * choose highest power _SxD or any lower power
+ */
+
+static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev)
+{
+ int acpi_state;
+
+ acpi_state = acpi_pm_device_sleep_state(&pdev->dev, NULL);
+ if (acpi_state < 0)
+ return PCI_POWER_ERROR;
+
+ switch (acpi_state) {
+ case ACPI_STATE_D0:
+ return PCI_D0;
+ case ACPI_STATE_D1:
+ return PCI_D1;
+ case ACPI_STATE_D2:
+ return PCI_D2;
+ case ACPI_STATE_D3:
+ return PCI_D3hot;
+ case ACPI_STATE_D3_COLD:
+ return PCI_D3cold;
+ }
+ return PCI_POWER_ERROR;
+}
+
+static bool acpi_pci_power_manageable(struct pci_dev *dev)
+{
+ acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
+
+ return handle ? acpi_bus_power_manageable(handle) : false;
+}
+
+static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
+{
+ acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
+ acpi_handle tmp;
+ static const u8 state_conv[] = {
+ [PCI_D0] = ACPI_STATE_D0,
+ [PCI_D1] = ACPI_STATE_D1,
+ [PCI_D2] = ACPI_STATE_D2,
+ [PCI_D3hot] = ACPI_STATE_D3,
+ [PCI_D3cold] = ACPI_STATE_D3
+ };
+ int error = -EINVAL;
+
+ /* If the ACPI device has _EJ0, ignore the device */
+ if (!handle || ACPI_SUCCESS(acpi_get_handle(handle, "_EJ0", &tmp)))
+ return -ENODEV;
+
+ switch (state) {
+ case PCI_D0:
+ case PCI_D1:
+ case PCI_D2:
+ case PCI_D3hot:
+ case PCI_D3cold:
+ error = acpi_bus_set_power(handle, state_conv[state]);
+ }
+
+ if (!error)
+ dev_printk(KERN_INFO, &dev->dev,
+ "power state changed by ACPI to D%d\n", state);
+
+ return error;
+}
+
+static bool acpi_pci_can_wakeup(struct pci_dev *dev)
+{
+ acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
+
+ return handle ? acpi_bus_can_wakeup(handle) : false;
+}
+
+static void acpi_pci_propagate_wakeup_enable(struct pci_bus *bus, bool enable)
+{
+ while (bus->parent) {
+ if (!acpi_pm_device_sleep_wake(&bus->self->dev, enable))
+ return;
+ bus = bus->parent;
+ }
+
+ /* We have reached the root bus. */
+ if (bus->bridge)
+ acpi_pm_device_sleep_wake(bus->bridge, enable);
+}
+
+static int acpi_pci_sleep_wake(struct pci_dev *dev, bool enable)
+{
+ if (acpi_pci_can_wakeup(dev))
+ return acpi_pm_device_sleep_wake(&dev->dev, enable);
+
+ acpi_pci_propagate_wakeup_enable(dev->bus, enable);
+ return 0;
+}
+
+/**
+ * acpi_dev_run_wake - Enable/disable wake-up for given device.
+ * @phys_dev: Device to enable/disable the platform to wake-up the system for.
+ * @enable: Whether enable or disable the wake-up functionality.
+ *
+ * Find the ACPI device object corresponding to @pci_dev and try to
+ * enable/disable the GPE associated with it.
+ */
+static int acpi_dev_run_wake(struct device *phys_dev, bool enable)
+{
+ struct acpi_device *dev;
+ acpi_handle handle;
+ int error = -ENODEV;
+
+ if (!device_run_wake(phys_dev))
+ return -EINVAL;
+
+ handle = DEVICE_ACPI_HANDLE(phys_dev);
+ if (!handle || ACPI_FAILURE(acpi_bus_get_device(handle, &dev))) {
+ dev_dbg(phys_dev, "ACPI handle has no context in %s!\n",
+ __func__);
+ return -ENODEV;
+ }
+
+ if (enable) {
+ acpi_enable_wakeup_device_power(dev, ACPI_STATE_S0);
+ acpi_enable_gpe(dev->wakeup.gpe_device, dev->wakeup.gpe_number);
+ } else {
+ acpi_disable_gpe(dev->wakeup.gpe_device, dev->wakeup.gpe_number);
+ acpi_disable_wakeup_device_power(dev);
+ }
+
+ return error;
+}
+
+static void acpi_pci_propagate_run_wake(struct pci_bus *bus, bool enable)
+{
+ while (bus->parent) {
+ struct pci_dev *bridge = bus->self;
+
+ if (bridge->pme_interrupt)
+ return;
+ if (!acpi_dev_run_wake(&bridge->dev, enable))
+ return;
+ bus = bus->parent;
+ }
+
+ /* We have reached the root bus. */
+ if (bus->bridge)
+ acpi_dev_run_wake(bus->bridge, enable);
+}
+
+static int acpi_pci_run_wake(struct pci_dev *dev, bool enable)
+{
+ if (dev->pme_interrupt)
+ return 0;
+
+ if (!acpi_dev_run_wake(&dev->dev, enable))
+ return 0;
+
+ acpi_pci_propagate_run_wake(dev->bus, enable);
+ return 0;
+}
+
+static struct pci_platform_pm_ops acpi_pci_platform_pm = {
+ .is_manageable = acpi_pci_power_manageable,
+ .set_state = acpi_pci_set_power_state,
+ .choose_state = acpi_pci_choose_state,
+ .can_wakeup = acpi_pci_can_wakeup,
+ .sleep_wake = acpi_pci_sleep_wake,
+ .run_wake = acpi_pci_run_wake,
+};
+
+/* ACPI bus type */
+static int acpi_pci_find_device(struct device *dev, acpi_handle *handle)
+{
+ struct pci_dev * pci_dev;
+ u64 addr;
+
+ pci_dev = to_pci_dev(dev);
+ /* Please ref to ACPI spec for the syntax of _ADR */
+ addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn);
+ *handle = acpi_get_child(DEVICE_ACPI_HANDLE(dev->parent), addr);
+ if (!*handle)
+ return -ENODEV;
+ return 0;
+}
+
+static int acpi_pci_find_root_bridge(struct device *dev, acpi_handle *handle)
+{
+ int num;
+ unsigned int seg, bus;
+
+ /*
+ * The string should be the same as root bridge's name
+ * Please look at 'pci_scan_bus_parented'
+ */
+ num = sscanf(dev_name(dev), "pci%04x:%02x", &seg, &bus);
+ if (num != 2)
+ return -ENODEV;
+ *handle = acpi_get_pci_rootbridge_handle(seg, bus);
+ if (!*handle)
+ return -ENODEV;
+ return 0;
+}
+
+static struct acpi_bus_type acpi_pci_bus = {
+ .bus = &pci_bus_type,
+ .find_device = acpi_pci_find_device,
+ .find_bridge = acpi_pci_find_root_bridge,
+};
+
+static int __init acpi_pci_init(void)
+{
+ int ret;
+
+ if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_MSI) {
+ printk(KERN_INFO"ACPI FADT declares the system doesn't support MSI, so disable it\n");
+ pci_no_msi();
+ }
+
+ 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_no_aspm();
+ }
+
+ ret = register_acpi_bus_type(&acpi_pci_bus);
+ if (ret)
+ return 0;
+ pci_set_platform_pm(&acpi_pci_platform_pm);
+ return 0;
+}
+arch_initcall(acpi_pci_init);