3 * Purpose: Provide PCI support in ACPI
5 * Copyright (C) 2005 David Shaohua Li <shaohua.li@intel.com>
6 * Copyright (C) 2004 Tom Long Nguyen <tom.l.nguyen@intel.com>
7 * Copyright (C) 2004 Intel Corp.
10 #include <linux/delay.h>
11 #include <linux/init.h>
12 #include <linux/pci.h>
13 #include <linux/module.h>
14 #include <linux/pci-aspm.h>
15 #include <linux/pci-acpi.h>
16 #include <linux/pm_runtime.h>
17 #include <linux/pm_qos.h>
21 * pci_acpi_wake_bus - Wake-up notification handler for root buses.
22 * @handle: ACPI handle of a device the notification is for.
23 * @event: Type of the signaled event.
24 * @context: PCI root bus to wake up devices on.
26 static void pci_acpi_wake_bus(acpi_handle handle, u32 event, void *context)
28 struct pci_bus *pci_bus = context;
30 if (event == ACPI_NOTIFY_DEVICE_WAKE && pci_bus)
31 pci_pme_wakeup_bus(pci_bus);
35 * pci_acpi_wake_dev - Wake-up notification handler for PCI devices.
36 * @handle: ACPI handle of a device the notification is for.
37 * @event: Type of the signaled event.
38 * @context: PCI device object to wake up.
40 static void pci_acpi_wake_dev(acpi_handle handle, u32 event, void *context)
42 struct pci_dev *pci_dev = context;
44 if (event != ACPI_NOTIFY_DEVICE_WAKE || !pci_dev)
47 if (pci_dev->pme_poll)
48 pci_dev->pme_poll = false;
50 if (pci_dev->current_state == PCI_D3cold) {
51 pci_wakeup_event(pci_dev);
52 pm_runtime_resume(&pci_dev->dev);
56 /* Clear PME Status if set. */
57 if (pci_dev->pme_support)
58 pci_check_pme_status(pci_dev);
60 pci_wakeup_event(pci_dev);
61 pm_runtime_resume(&pci_dev->dev);
63 if (pci_dev->subordinate)
64 pci_pme_wakeup_bus(pci_dev->subordinate);
68 * pci_acpi_add_bus_pm_notifier - Register PM notifier for given PCI bus.
69 * @dev: ACPI device to add the notifier for.
70 * @pci_bus: PCI bus to walk checking for PME status if an event is signaled.
72 acpi_status pci_acpi_add_bus_pm_notifier(struct acpi_device *dev,
73 struct pci_bus *pci_bus)
75 return acpi_add_pm_notifier(dev, pci_acpi_wake_bus, pci_bus);
79 * pci_acpi_remove_bus_pm_notifier - Unregister PCI bus PM notifier.
80 * @dev: ACPI device to remove the notifier from.
82 acpi_status pci_acpi_remove_bus_pm_notifier(struct acpi_device *dev)
84 return acpi_remove_pm_notifier(dev, pci_acpi_wake_bus);
88 * pci_acpi_add_pm_notifier - Register PM notifier for given PCI device.
89 * @dev: ACPI device to add the notifier for.
90 * @pci_dev: PCI device to check for the PME status if an event is signaled.
92 acpi_status pci_acpi_add_pm_notifier(struct acpi_device *dev,
93 struct pci_dev *pci_dev)
95 return acpi_add_pm_notifier(dev, pci_acpi_wake_dev, pci_dev);
99 * pci_acpi_remove_pm_notifier - Unregister PCI device PM notifier.
100 * @dev: ACPI device to remove the notifier from.
102 acpi_status pci_acpi_remove_pm_notifier(struct acpi_device *dev)
104 return acpi_remove_pm_notifier(dev, pci_acpi_wake_dev);
107 phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle)
109 acpi_status status = AE_NOT_EXIST;
110 unsigned long long mcfg_addr;
113 status = acpi_evaluate_integer(handle, METHOD_NAME__CBA,
115 if (ACPI_FAILURE(status))
118 return (phys_addr_t)mcfg_addr;
122 * _SxD returns the D-state with the highest power
123 * (lowest D-state number) supported in the S-state "x".
125 * If the devices does not have a _PRW
126 * (Power Resources for Wake) supporting system wakeup from "x"
127 * then the OS is free to choose a lower power (higher number
128 * D-state) than the return value from _SxD.
130 * But if _PRW is enabled at S-state "x", the OS
131 * must not choose a power lower than _SxD --
132 * unless the device has an _SxW method specifying
133 * the lowest power (highest D-state number) the device
134 * may enter while still able to wake the system.
136 * ie. depending on global OS policy:
138 * if (_PRW at S-state x)
139 * choose from highest power _SxD to lowest power _SxW
140 * else // no _PRW at S-state x
141 * choose highest power _SxD or any lower power
144 static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev)
146 int acpi_state, d_max;
149 d_max = ACPI_STATE_D3_HOT;
151 d_max = ACPI_STATE_D3_COLD;
152 acpi_state = acpi_pm_device_sleep_state(&pdev->dev, NULL, d_max);
154 return PCI_POWER_ERROR;
156 switch (acpi_state) {
163 case ACPI_STATE_D3_HOT:
165 case ACPI_STATE_D3_COLD:
168 return PCI_POWER_ERROR;
171 static bool acpi_pci_power_manageable(struct pci_dev *dev)
173 struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
174 return adev ? acpi_device_power_manageable(adev) : false;
177 static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
179 struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
180 static const u8 state_conv[] = {
181 [PCI_D0] = ACPI_STATE_D0,
182 [PCI_D1] = ACPI_STATE_D1,
183 [PCI_D2] = ACPI_STATE_D2,
184 [PCI_D3hot] = ACPI_STATE_D3_COLD,
185 [PCI_D3cold] = ACPI_STATE_D3_COLD,
189 /* If the ACPI device has _EJ0, ignore the device */
190 if (!adev || acpi_has_method(adev->handle, "_EJ0"))
195 if (dev_pm_qos_flags(&dev->dev, PM_QOS_FLAG_NO_POWER_OFF) ==
204 error = acpi_device_set_power(adev, state_conv[state]);
208 dev_dbg(&dev->dev, "power state changed by ACPI to %s\n",
209 acpi_power_state_string(state_conv[state]));
214 static bool acpi_pci_can_wakeup(struct pci_dev *dev)
216 struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
217 return adev ? acpi_device_can_wakeup(adev) : false;
220 static void acpi_pci_propagate_wakeup_enable(struct pci_bus *bus, bool enable)
222 while (bus->parent) {
223 if (!acpi_pm_device_sleep_wake(&bus->self->dev, enable))
228 /* We have reached the root bus. */
230 acpi_pm_device_sleep_wake(bus->bridge, enable);
233 static int acpi_pci_sleep_wake(struct pci_dev *dev, bool enable)
235 if (acpi_pci_can_wakeup(dev))
236 return acpi_pm_device_sleep_wake(&dev->dev, enable);
238 acpi_pci_propagate_wakeup_enable(dev->bus, enable);
242 static void acpi_pci_propagate_run_wake(struct pci_bus *bus, bool enable)
244 while (bus->parent) {
245 struct pci_dev *bridge = bus->self;
247 if (bridge->pme_interrupt)
249 if (!acpi_pm_device_run_wake(&bridge->dev, enable))
254 /* We have reached the root bus. */
256 acpi_pm_device_run_wake(bus->bridge, enable);
259 static int acpi_pci_run_wake(struct pci_dev *dev, bool enable)
262 * Per PCI Express Base Specification Revision 2.0 section
263 * 5.3.3.2 Link Wakeup, platform support is needed for D3cold
264 * waking up to power on the main link even if there is PME
267 if (dev->pme_interrupt && !dev->runtime_d3cold)
270 if (!acpi_pm_device_run_wake(&dev->dev, enable))
273 acpi_pci_propagate_run_wake(dev->bus, enable);
277 static struct pci_platform_pm_ops acpi_pci_platform_pm = {
278 .is_manageable = acpi_pci_power_manageable,
279 .set_state = acpi_pci_set_power_state,
280 .choose_state = acpi_pci_choose_state,
281 .sleep_wake = acpi_pci_sleep_wake,
282 .run_wake = acpi_pci_run_wake,
285 void acpi_pci_add_bus(struct pci_bus *bus)
287 if (acpi_pci_disabled || !bus->bridge)
290 acpi_pci_slot_enumerate(bus);
291 acpiphp_enumerate_slots(bus);
294 void acpi_pci_remove_bus(struct pci_bus *bus)
296 if (acpi_pci_disabled || !bus->bridge)
299 acpiphp_remove_slots(bus);
300 acpi_pci_slot_remove(bus);
304 static struct acpi_device *acpi_pci_find_companion(struct device *dev)
306 struct pci_dev *pci_dev = to_pci_dev(dev);
310 check_children = pci_is_bridge(pci_dev);
311 /* Please ref to ACPI spec for the syntax of _ADR */
312 addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn);
313 return acpi_find_child_device(ACPI_COMPANION(dev->parent), addr,
317 static void pci_acpi_setup(struct device *dev)
319 struct pci_dev *pci_dev = to_pci_dev(dev);
320 struct acpi_device *adev = ACPI_COMPANION(dev);
325 pci_acpi_add_pm_notifier(adev, pci_dev);
326 if (!adev->wakeup.flags.valid)
329 device_set_wakeup_capable(dev, true);
330 acpi_pci_sleep_wake(pci_dev, false);
331 if (adev->wakeup.flags.run_wake)
332 device_set_run_wake(dev, true);
335 static void pci_acpi_cleanup(struct device *dev)
337 struct acpi_device *adev = ACPI_COMPANION(dev);
342 pci_acpi_remove_pm_notifier(adev);
343 if (adev->wakeup.flags.valid) {
344 device_set_wakeup_capable(dev, false);
345 device_set_run_wake(dev, false);
349 static bool pci_acpi_bus_match(struct device *dev)
351 return dev_is_pci(dev);
354 static struct acpi_bus_type acpi_pci_bus = {
356 .match = pci_acpi_bus_match,
357 .find_companion = acpi_pci_find_companion,
358 .setup = pci_acpi_setup,
359 .cleanup = pci_acpi_cleanup,
362 static int __init acpi_pci_init(void)
366 if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_MSI) {
367 pr_info("ACPI FADT declares the system doesn't support MSI, so disable it\n");
371 if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
372 pr_info("ACPI FADT declares the system doesn't support PCIe ASPM, so disable it\n");
376 ret = register_acpi_bus_type(&acpi_pci_bus);
380 pci_set_platform_pm(&acpi_pci_platform_pm);
381 acpi_pci_slot_init();
386 arch_initcall(acpi_pci_init);