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 - Root bus wakeup notification fork function.
22 * @work: Work item to handle.
24 static void pci_acpi_wake_bus(struct work_struct *work)
26 struct acpi_device *adev;
27 struct acpi_pci_root *root;
29 adev = container_of(work, struct acpi_device, wakeup.context.work);
30 root = acpi_driver_data(adev);
31 pci_pme_wakeup_bus(root->bus);
35 * pci_acpi_wake_dev - PCI device wakeup notification work function.
36 * @handle: ACPI handle of a device the notification is for.
37 * @work: Work item to handle.
39 static void pci_acpi_wake_dev(struct work_struct *work)
41 struct acpi_device_wakeup_context *context;
42 struct pci_dev *pci_dev;
44 context = container_of(work, struct acpi_device_wakeup_context, work);
45 pci_dev = to_pci_dev(context->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 root PCI bus.
69 * @dev: PCI root bridge ACPI device.
71 acpi_status pci_acpi_add_bus_pm_notifier(struct acpi_device *dev)
73 return acpi_add_pm_notifier(dev, NULL, pci_acpi_wake_bus);
77 * pci_acpi_add_pm_notifier - Register PM notifier for given PCI device.
78 * @dev: ACPI device to add the notifier for.
79 * @pci_dev: PCI device to check for the PME status if an event is signaled.
81 acpi_status pci_acpi_add_pm_notifier(struct acpi_device *dev,
82 struct pci_dev *pci_dev)
84 return acpi_add_pm_notifier(dev, &pci_dev->dev, pci_acpi_wake_dev);
87 phys_addr_t acpi_pci_root_get_mcfg_addr(acpi_handle handle)
89 acpi_status status = AE_NOT_EXIST;
90 unsigned long long mcfg_addr;
93 status = acpi_evaluate_integer(handle, METHOD_NAME__CBA,
95 if (ACPI_FAILURE(status))
98 return (phys_addr_t)mcfg_addr;
102 * _SxD returns the D-state with the highest power
103 * (lowest D-state number) supported in the S-state "x".
105 * If the devices does not have a _PRW
106 * (Power Resources for Wake) supporting system wakeup from "x"
107 * then the OS is free to choose a lower power (higher number
108 * D-state) than the return value from _SxD.
110 * But if _PRW is enabled at S-state "x", the OS
111 * must not choose a power lower than _SxD --
112 * unless the device has an _SxW method specifying
113 * the lowest power (highest D-state number) the device
114 * may enter while still able to wake the system.
116 * ie. depending on global OS policy:
118 * if (_PRW at S-state x)
119 * choose from highest power _SxD to lowest power _SxW
120 * else // no _PRW at S-state x
121 * choose highest power _SxD or any lower power
124 static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev)
126 int acpi_state, d_max;
129 d_max = ACPI_STATE_D3_HOT;
131 d_max = ACPI_STATE_D3_COLD;
132 acpi_state = acpi_pm_device_sleep_state(&pdev->dev, NULL, d_max);
134 return PCI_POWER_ERROR;
136 switch (acpi_state) {
143 case ACPI_STATE_D3_HOT:
145 case ACPI_STATE_D3_COLD:
148 return PCI_POWER_ERROR;
151 static bool acpi_pci_power_manageable(struct pci_dev *dev)
153 struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
154 return adev ? acpi_device_power_manageable(adev) : false;
157 static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
159 struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
160 static const u8 state_conv[] = {
161 [PCI_D0] = ACPI_STATE_D0,
162 [PCI_D1] = ACPI_STATE_D1,
163 [PCI_D2] = ACPI_STATE_D2,
164 [PCI_D3hot] = ACPI_STATE_D3_COLD,
165 [PCI_D3cold] = ACPI_STATE_D3_COLD,
169 /* If the ACPI device has _EJ0, ignore the device */
170 if (!adev || acpi_has_method(adev->handle, "_EJ0"))
175 if (dev_pm_qos_flags(&dev->dev, PM_QOS_FLAG_NO_POWER_OFF) ==
184 error = acpi_device_set_power(adev, state_conv[state]);
188 dev_dbg(&dev->dev, "power state changed by ACPI to %s\n",
189 acpi_power_state_string(state_conv[state]));
194 static bool acpi_pci_can_wakeup(struct pci_dev *dev)
196 struct acpi_device *adev = ACPI_COMPANION(&dev->dev);
197 return adev ? acpi_device_can_wakeup(adev) : false;
200 static void acpi_pci_propagate_wakeup_enable(struct pci_bus *bus, bool enable)
202 while (bus->parent) {
203 if (!acpi_pm_device_sleep_wake(&bus->self->dev, enable))
208 /* We have reached the root bus. */
210 acpi_pm_device_sleep_wake(bus->bridge, enable);
213 static int acpi_pci_sleep_wake(struct pci_dev *dev, bool enable)
215 if (acpi_pci_can_wakeup(dev))
216 return acpi_pm_device_sleep_wake(&dev->dev, enable);
218 acpi_pci_propagate_wakeup_enable(dev->bus, enable);
222 static void acpi_pci_propagate_run_wake(struct pci_bus *bus, bool enable)
224 while (bus->parent) {
225 struct pci_dev *bridge = bus->self;
227 if (bridge->pme_interrupt)
229 if (!acpi_pm_device_run_wake(&bridge->dev, enable))
234 /* We have reached the root bus. */
236 acpi_pm_device_run_wake(bus->bridge, enable);
239 static int acpi_pci_run_wake(struct pci_dev *dev, bool enable)
242 * Per PCI Express Base Specification Revision 2.0 section
243 * 5.3.3.2 Link Wakeup, platform support is needed for D3cold
244 * waking up to power on the main link even if there is PME
247 if (dev->pme_interrupt && !dev->runtime_d3cold)
250 if (!acpi_pm_device_run_wake(&dev->dev, enable))
253 acpi_pci_propagate_run_wake(dev->bus, enable);
257 static struct pci_platform_pm_ops acpi_pci_platform_pm = {
258 .is_manageable = acpi_pci_power_manageable,
259 .set_state = acpi_pci_set_power_state,
260 .choose_state = acpi_pci_choose_state,
261 .sleep_wake = acpi_pci_sleep_wake,
262 .run_wake = acpi_pci_run_wake,
265 void acpi_pci_add_bus(struct pci_bus *bus)
267 if (acpi_pci_disabled || !bus->bridge)
270 acpi_pci_slot_enumerate(bus);
271 acpiphp_enumerate_slots(bus);
274 void acpi_pci_remove_bus(struct pci_bus *bus)
276 if (acpi_pci_disabled || !bus->bridge)
279 acpiphp_remove_slots(bus);
280 acpi_pci_slot_remove(bus);
284 static struct acpi_device *acpi_pci_find_companion(struct device *dev)
286 struct pci_dev *pci_dev = to_pci_dev(dev);
290 check_children = pci_is_bridge(pci_dev);
291 /* Please ref to ACPI spec for the syntax of _ADR */
292 addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn);
293 return acpi_find_child_device(ACPI_COMPANION(dev->parent), addr,
297 static void pci_acpi_setup(struct device *dev)
299 struct pci_dev *pci_dev = to_pci_dev(dev);
300 struct acpi_device *adev = ACPI_COMPANION(dev);
305 pci_acpi_add_pm_notifier(adev, pci_dev);
306 if (!adev->wakeup.flags.valid)
309 device_set_wakeup_capable(dev, true);
310 acpi_pci_sleep_wake(pci_dev, false);
311 if (adev->wakeup.flags.run_wake)
312 device_set_run_wake(dev, true);
315 static void pci_acpi_cleanup(struct device *dev)
317 struct acpi_device *adev = ACPI_COMPANION(dev);
322 pci_acpi_remove_pm_notifier(adev);
323 if (adev->wakeup.flags.valid) {
324 device_set_wakeup_capable(dev, false);
325 device_set_run_wake(dev, false);
329 static bool pci_acpi_bus_match(struct device *dev)
331 return dev_is_pci(dev);
334 static struct acpi_bus_type acpi_pci_bus = {
336 .match = pci_acpi_bus_match,
337 .find_companion = acpi_pci_find_companion,
338 .setup = pci_acpi_setup,
339 .cleanup = pci_acpi_cleanup,
342 static int __init acpi_pci_init(void)
346 if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_MSI) {
347 pr_info("ACPI FADT declares the system doesn't support MSI, so disable it\n");
351 if (acpi_gbl_FADT.boot_flags & ACPI_FADT_NO_ASPM) {
352 pr_info("ACPI FADT declares the system doesn't support PCIe ASPM, so disable it\n");
356 ret = register_acpi_bus_type(&acpi_pci_bus);
360 pci_set_platform_pm(&acpi_pci_platform_pm);
361 acpi_pci_slot_init();
366 arch_initcall(acpi_pci_init);