| /* |
| * 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_check_pme_status(pci_dev); |
| pm_runtime_resume(&pci_dev->dev); |
| pci_wakeup_event(pci_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; |
| } |
| 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) { |
| if (!dev->wakeup.run_wake_count++) { |
| acpi_enable_wakeup_device_power(dev, ACPI_STATE_S0); |
| acpi_enable_gpe(dev->wakeup.gpe_device, |
| dev->wakeup.gpe_number, |
| ACPI_GPE_TYPE_RUNTIME); |
| } |
| } else if (dev->wakeup.run_wake_count > 0) { |
| if (!--dev->wakeup.run_wake_count) { |
| acpi_disable_gpe(dev->wakeup.gpe_device, |
| dev->wakeup.gpe_number, |
| ACPI_GPE_TYPE_RUNTIME); |
| acpi_disable_wakeup_device_power(dev); |
| } |
| } else { |
| error = -EALREADY; |
| } |
| |
| 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); |