/*
* 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 = 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 = ACPI_HANDLE(&dev->dev);
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_COLD,
[PCI_D3cold] = ACPI_STATE_D3_COLD,
};
int error = -EINVAL;
/* If the ACPI device has _EJ0, ignore the device */
if (!handle || acpi_has_method(handle, "_EJ0"))
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_dbg(&dev->dev, "power state changed by ACPI to %s\n",
acpi_power_state_string(state_conv[state]));
return error;
}
static bool acpi_pci_can_wakeup(struct pci_dev *dev)
{
acpi_handle handle = 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)
{
if (acpi_pci_disabled || !bus->bridge)
return;
acpi_pci_slot_enumerate(bus);
acpiphp_enumerate_slots(bus);
}
void acpi_pci_remove_bus(struct pci_bus *bus)
{
if (acpi_pci_disabled || !bus->bridge)
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) {
pr_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) {
pr_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);
