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 <acpi/acpi.h>
16 #include <acpi/acpi_bus.h>
18 #include <linux/pci-acpi.h>
19 #include <linux/pm_runtime.h>
20 #include <linux/pm_qos.h>
23 static DEFINE_MUTEX(pci_acpi_pm_notify_mtx
);
26 * pci_acpi_wake_bus - Wake-up notification handler for root buses.
27 * @handle: ACPI handle of a device the notification is for.
28 * @event: Type of the signaled event.
29 * @context: PCI root bus to wake up devices on.
31 static void pci_acpi_wake_bus(acpi_handle handle
, u32 event
, void *context
)
33 struct pci_bus
*pci_bus
= context
;
35 if (event
== ACPI_NOTIFY_DEVICE_WAKE
&& pci_bus
)
36 pci_pme_wakeup_bus(pci_bus
);
40 * pci_acpi_wake_dev - Wake-up notification handler for PCI devices.
41 * @handle: ACPI handle of a device the notification is for.
42 * @event: Type of the signaled event.
43 * @context: PCI device object to wake up.
45 static void pci_acpi_wake_dev(acpi_handle handle
, u32 event
, void *context
)
47 struct pci_dev
*pci_dev
= context
;
49 if (event
!= ACPI_NOTIFY_DEVICE_WAKE
|| !pci_dev
)
52 if (pci_dev
->current_state
== PCI_D3cold
) {
53 pci_wakeup_event(pci_dev
);
54 pm_runtime_resume(&pci_dev
->dev
);
58 if (!pci_dev
->pm_cap
|| !pci_dev
->pme_support
59 || pci_check_pme_status(pci_dev
)) {
60 if (pci_dev
->pme_poll
)
61 pci_dev
->pme_poll
= false;
63 pci_wakeup_event(pci_dev
);
64 pm_runtime_resume(&pci_dev
->dev
);
67 if (pci_dev
->subordinate
)
68 pci_pme_wakeup_bus(pci_dev
->subordinate
);
72 * add_pm_notifier - Register PM notifier for given ACPI device.
73 * @dev: ACPI device to add the notifier for.
74 * @context: PCI device or bus to check for PME status if an event is signaled.
76 * NOTE: @dev need not be a run-wake or wake-up device to be a valid source of
77 * PM wake-up events. For example, wake-up events may be generated for bridges
78 * if one of the devices below the bridge is signaling PME, even if the bridge
79 * itself doesn't have a wake-up GPE associated with it.
81 static acpi_status
add_pm_notifier(struct acpi_device
*dev
,
82 acpi_notify_handler handler
,
85 acpi_status status
= AE_ALREADY_EXISTS
;
87 mutex_lock(&pci_acpi_pm_notify_mtx
);
89 if (dev
->wakeup
.flags
.notifier_present
)
92 status
= acpi_install_notify_handler(dev
->handle
,
95 if (ACPI_FAILURE(status
))
98 dev
->wakeup
.flags
.notifier_present
= true;
101 mutex_unlock(&pci_acpi_pm_notify_mtx
);
106 * remove_pm_notifier - Unregister PM notifier from given ACPI device.
107 * @dev: ACPI device to remove the notifier from.
109 static acpi_status
remove_pm_notifier(struct acpi_device
*dev
,
110 acpi_notify_handler handler
)
112 acpi_status status
= AE_BAD_PARAMETER
;
114 mutex_lock(&pci_acpi_pm_notify_mtx
);
116 if (!dev
->wakeup
.flags
.notifier_present
)
119 status
= acpi_remove_notify_handler(dev
->handle
,
122 if (ACPI_FAILURE(status
))
125 dev
->wakeup
.flags
.notifier_present
= false;
128 mutex_unlock(&pci_acpi_pm_notify_mtx
);
133 * pci_acpi_add_bus_pm_notifier - Register PM notifier for given PCI bus.
134 * @dev: ACPI device to add the notifier for.
135 * @pci_bus: PCI bus to walk checking for PME status if an event is signaled.
137 acpi_status
pci_acpi_add_bus_pm_notifier(struct acpi_device
*dev
,
138 struct pci_bus
*pci_bus
)
140 return add_pm_notifier(dev
, pci_acpi_wake_bus
, pci_bus
);
144 * pci_acpi_remove_bus_pm_notifier - Unregister PCI bus PM notifier.
145 * @dev: ACPI device to remove the notifier from.
147 acpi_status
pci_acpi_remove_bus_pm_notifier(struct acpi_device
*dev
)
149 return remove_pm_notifier(dev
, pci_acpi_wake_bus
);
153 * pci_acpi_add_pm_notifier - Register PM notifier for given PCI device.
154 * @dev: ACPI device to add the notifier for.
155 * @pci_dev: PCI device to check for the PME status if an event is signaled.
157 acpi_status
pci_acpi_add_pm_notifier(struct acpi_device
*dev
,
158 struct pci_dev
*pci_dev
)
160 return add_pm_notifier(dev
, pci_acpi_wake_dev
, pci_dev
);
164 * pci_acpi_remove_pm_notifier - Unregister PCI device PM notifier.
165 * @dev: ACPI device to remove the notifier from.
167 acpi_status
pci_acpi_remove_pm_notifier(struct acpi_device
*dev
)
169 return remove_pm_notifier(dev
, pci_acpi_wake_dev
);
172 phys_addr_t
acpi_pci_root_get_mcfg_addr(acpi_handle handle
)
174 acpi_status status
= AE_NOT_EXIST
;
175 unsigned long long mcfg_addr
;
178 status
= acpi_evaluate_integer(handle
, METHOD_NAME__CBA
,
180 if (ACPI_FAILURE(status
))
183 return (phys_addr_t
)mcfg_addr
;
187 * _SxD returns the D-state with the highest power
188 * (lowest D-state number) supported in the S-state "x".
190 * If the devices does not have a _PRW
191 * (Power Resources for Wake) supporting system wakeup from "x"
192 * then the OS is free to choose a lower power (higher number
193 * D-state) than the return value from _SxD.
195 * But if _PRW is enabled at S-state "x", the OS
196 * must not choose a power lower than _SxD --
197 * unless the device has an _SxW method specifying
198 * the lowest power (highest D-state number) the device
199 * may enter while still able to wake the system.
201 * ie. depending on global OS policy:
203 * if (_PRW at S-state x)
204 * choose from highest power _SxD to lowest power _SxW
205 * else // no _PRW at S-state x
206 * choose highest power _SxD or any lower power
209 static pci_power_t
acpi_pci_choose_state(struct pci_dev
*pdev
)
211 int acpi_state
, d_max
;
214 d_max
= ACPI_STATE_D3_HOT
;
216 d_max
= ACPI_STATE_D3_COLD
;
217 acpi_state
= acpi_pm_device_sleep_state(&pdev
->dev
, NULL
, d_max
);
219 return PCI_POWER_ERROR
;
221 switch (acpi_state
) {
228 case ACPI_STATE_D3_HOT
:
230 case ACPI_STATE_D3_COLD
:
233 return PCI_POWER_ERROR
;
236 static bool acpi_pci_power_manageable(struct pci_dev
*dev
)
238 acpi_handle handle
= DEVICE_ACPI_HANDLE(&dev
->dev
);
240 return handle
? acpi_bus_power_manageable(handle
) : false;
243 static int acpi_pci_set_power_state(struct pci_dev
*dev
, pci_power_t state
)
245 acpi_handle handle
= DEVICE_ACPI_HANDLE(&dev
->dev
);
247 static const u8 state_conv
[] = {
248 [PCI_D0
] = ACPI_STATE_D0
,
249 [PCI_D1
] = ACPI_STATE_D1
,
250 [PCI_D2
] = ACPI_STATE_D2
,
251 [PCI_D3hot
] = ACPI_STATE_D3
,
252 [PCI_D3cold
] = ACPI_STATE_D3
256 /* If the ACPI device has _EJ0, ignore the device */
257 if (!handle
|| ACPI_SUCCESS(acpi_get_handle(handle
, "_EJ0", &tmp
)))
262 if (dev_pm_qos_flags(&dev
->dev
, PM_QOS_FLAG_NO_POWER_OFF
) ==
271 error
= acpi_bus_set_power(handle
, state_conv
[state
]);
275 dev_info(&dev
->dev
, "power state changed by ACPI to %s\n",
276 pci_power_name(state
));
281 static bool acpi_pci_can_wakeup(struct pci_dev
*dev
)
283 acpi_handle handle
= DEVICE_ACPI_HANDLE(&dev
->dev
);
285 return handle
? acpi_bus_can_wakeup(handle
) : false;
288 static void acpi_pci_propagate_wakeup_enable(struct pci_bus
*bus
, bool enable
)
290 while (bus
->parent
) {
291 if (!acpi_pm_device_sleep_wake(&bus
->self
->dev
, enable
))
296 /* We have reached the root bus. */
298 acpi_pm_device_sleep_wake(bus
->bridge
, enable
);
301 static int acpi_pci_sleep_wake(struct pci_dev
*dev
, bool enable
)
303 if (acpi_pci_can_wakeup(dev
))
304 return acpi_pm_device_sleep_wake(&dev
->dev
, enable
);
306 acpi_pci_propagate_wakeup_enable(dev
->bus
, enable
);
310 static void acpi_pci_propagate_run_wake(struct pci_bus
*bus
, bool enable
)
312 while (bus
->parent
) {
313 struct pci_dev
*bridge
= bus
->self
;
315 if (bridge
->pme_interrupt
)
317 if (!acpi_pm_device_run_wake(&bridge
->dev
, enable
))
322 /* We have reached the root bus. */
324 acpi_pm_device_run_wake(bus
->bridge
, enable
);
327 static int acpi_pci_run_wake(struct pci_dev
*dev
, bool enable
)
330 * Per PCI Express Base Specification Revision 2.0 section
331 * 5.3.3.2 Link Wakeup, platform support is needed for D3cold
332 * waking up to power on the main link even if there is PME
335 if (dev
->pme_interrupt
&& !dev
->runtime_d3cold
)
338 if (!acpi_pm_device_run_wake(&dev
->dev
, enable
))
341 acpi_pci_propagate_run_wake(dev
->bus
, enable
);
345 static struct pci_platform_pm_ops acpi_pci_platform_pm
= {
346 .is_manageable
= acpi_pci_power_manageable
,
347 .set_state
= acpi_pci_set_power_state
,
348 .choose_state
= acpi_pci_choose_state
,
349 .can_wakeup
= acpi_pci_can_wakeup
,
350 .sleep_wake
= acpi_pci_sleep_wake
,
351 .run_wake
= acpi_pci_run_wake
,
355 static int acpi_pci_find_device(struct device
*dev
, acpi_handle
*handle
)
357 struct pci_dev
* pci_dev
;
360 pci_dev
= to_pci_dev(dev
);
361 /* Please ref to ACPI spec for the syntax of _ADR */
362 addr
= (PCI_SLOT(pci_dev
->devfn
) << 16) | PCI_FUNC(pci_dev
->devfn
);
363 *handle
= acpi_get_child(DEVICE_ACPI_HANDLE(dev
->parent
), addr
);
369 static int acpi_pci_find_root_bridge(struct device
*dev
, acpi_handle
*handle
)
372 unsigned int seg
, bus
;
375 * The string should be the same as root bridge's name
376 * Please look at 'pci_scan_bus_parented'
378 num
= sscanf(dev_name(dev
), "pci%04x:%02x", &seg
, &bus
);
381 *handle
= acpi_get_pci_rootbridge_handle(seg
, bus
);
387 static struct acpi_bus_type acpi_pci_bus
= {
388 .bus
= &pci_bus_type
,
389 .find_device
= acpi_pci_find_device
,
390 .find_bridge
= acpi_pci_find_root_bridge
,
393 static int __init
acpi_pci_init(void)
397 if (acpi_gbl_FADT
.boot_flags
& ACPI_FADT_NO_MSI
) {
398 printk(KERN_INFO
"ACPI FADT declares the system doesn't support MSI, so disable it\n");
402 if (acpi_gbl_FADT
.boot_flags
& ACPI_FADT_NO_ASPM
) {
403 printk(KERN_INFO
"ACPI FADT declares the system doesn't support PCIe ASPM, so disable it\n");
407 ret
= register_acpi_bus_type(&acpi_pci_bus
);
410 pci_set_platform_pm(&acpi_pci_platform_pm
);
413 arch_initcall(acpi_pci_init
);