diff options
Diffstat (limited to 'drivers/pci/pci-acpi.c')
| -rw-r--r-- | drivers/pci/pci-acpi.c | 405 |
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..0eab3a3c --- /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 <linux/pm_qos.h> +#include "pci.h" + +/** + * 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) + return; + + if (pci_dev->pme_poll) + pci_dev->pme_poll = false; + + if (pci_dev->current_state == PCI_D3cold) { + pci_wakeup_event(pci_dev); + pm_runtime_resume(&pci_dev->dev); + return; + } + + /* Clear PME Status if set. */ + if (pci_dev->pme_support) + pci_check_pme_status(pci_dev); + + pci_wakeup_event(pci_dev); + pm_runtime_resume(&pci_dev->dev); + + if (pci_dev->subordinate) + pci_pme_wakeup_bus(pci_dev->subordinate); +} + +/** + * 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 acpi_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 acpi_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 acpi_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 acpi_remove_pm_notifier(dev, pci_acpi_wake_dev); +} + +phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle) +{ + acpi_status status = AE_NOT_EXIST; + unsigned long long mcfg_addr; + + if (handle) + status = acpi_evaluate_integer(handle, METHOD_NAME__CBA, + NULL, &mcfg_addr); + if (ACPI_FAILURE(status)) + return 0; + + return (phys_addr_t)mcfg_addr; +} + +/* + * _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, d_max; + + if (pdev->no_d3cold) + d_max = ACPI_STATE_D3_HOT; + else + d_max = ACPI_STATE_D3_COLD; + acpi_state = acpi_pm_device_sleep_state(&pdev->dev, NULL, d_max); + 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_HOT: + 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_D3cold: + if (dev_pm_qos_flags(&dev->dev, PM_QOS_FLAG_NO_POWER_OFF) == + PM_QOS_FLAGS_ALL) { + error = -EBUSY; + break; + } + case PCI_D0: + case PCI_D1: + case PCI_D2: + case PCI_D3hot: + error = acpi_bus_set_power(handle, state_conv[state]); + } + + if (!error) + dev_info(&dev->dev, "power state changed by ACPI to %s\n", + pci_power_name(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; +} + +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_pm_device_run_wake(&bridge->dev, enable)) + return; + bus = bus->parent; + } + + /* We have reached the root bus. */ + if (bus->bridge) + acpi_pm_device_run_wake(bus->bridge, enable); +} + +static int acpi_pci_run_wake(struct pci_dev *dev, bool enable) +{ + /* + * Per PCI Express Base Specification Revision 2.0 section + * 5.3.3.2 Link Wakeup, platform support is needed for D3cold + * waking up to power on the main link even if there is PME + * support for D3cold + */ + if (dev->pme_interrupt && !dev->runtime_d3cold) + return 0; + + if (!acpi_pm_device_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, + .sleep_wake = acpi_pci_sleep_wake, + .run_wake = acpi_pci_run_wake, +}; + +void acpi_pci_add_bus(struct pci_bus *bus) +{ + acpi_handle handle = NULL; + + if (bus->bridge) + handle = ACPI_HANDLE(bus->bridge); + if (acpi_pci_disabled || handle == NULL) + return; + + acpi_pci_slot_enumerate(bus, handle); + acpiphp_enumerate_slots(bus, handle); +} + +void acpi_pci_remove_bus(struct pci_bus *bus) +{ + /* + * bus->bridge->acpi_node.handle has already been reset to NULL + * when acpi_pci_remove_bus() is called, so don't check ACPI handle. + */ + if (acpi_pci_disabled) + return; + + acpiphp_remove_slots(bus); + acpi_pci_slot_remove(bus); +} + +/* ACPI bus type */ +static int acpi_pci_find_device(struct device *dev, acpi_handle *handle) +{ + struct pci_dev *pci_dev = to_pci_dev(dev); + bool is_bridge; + u64 addr; + + /* + * pci_is_bridge() is not suitable here, because pci_dev->subordinate + * is set only after acpi_pci_find_device() has been called for the + * given device. + */ + is_bridge = pci_dev->hdr_type == PCI_HEADER_TYPE_BRIDGE + || pci_dev->hdr_type == PCI_HEADER_TYPE_CARDBUS; + /* Please ref to ACPI spec for the syntax of _ADR */ + addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn); + *handle = acpi_find_child(ACPI_HANDLE(dev->parent), addr, is_bridge); + if (!*handle) + return -ENODEV; + return 0; +} + +static void pci_acpi_setup(struct device *dev) +{ + struct pci_dev *pci_dev = to_pci_dev(dev); + acpi_handle handle = ACPI_HANDLE(dev); + struct acpi_device *adev; + + if (acpi_bus_get_device(handle, &adev) || !adev->wakeup.flags.valid) + return; + + device_set_wakeup_capable(dev, true); + acpi_pci_sleep_wake(pci_dev, false); + + pci_acpi_add_pm_notifier(adev, pci_dev); + if (adev->wakeup.flags.run_wake) + device_set_run_wake(dev, true); +} + +static void pci_acpi_cleanup(struct device *dev) +{ + acpi_handle handle = ACPI_HANDLE(dev); + struct acpi_device *adev; + + if (!acpi_bus_get_device(handle, &adev) && adev->wakeup.flags.valid) { + device_set_wakeup_capable(dev, false); + device_set_run_wake(dev, false); + pci_acpi_remove_pm_notifier(adev); + } +} + +static bool pci_acpi_bus_match(struct device *dev) +{ + return dev->bus == &pci_bus_type; +} + +static struct acpi_bus_type acpi_pci_bus = { + .name = "PCI", + .match = pci_acpi_bus_match, + .find_device = acpi_pci_find_device, + .setup = pci_acpi_setup, + .cleanup = pci_acpi_cleanup, +}; + +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); + acpi_pci_slot_init(); + acpiphp_init(); + + return 0; +} +arch_initcall(acpi_pci_init); |
