PCI: disable ASPM per ACPI FADT setting
[linux-2.6/mini2440.git] / drivers / pci / pci-acpi.c
blob89a2f0fa10f91d79b216bc78da9d19eb0fbd3941
1 /*
2 * File: pci-acpi.c
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.
8 */
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/acnamesp.h>
17 #include <acpi/acresrc.h>
18 #include <acpi/acpi_bus.h>
20 #include <linux/pci-acpi.h>
21 #include "pci.h"
23 struct acpi_osc_data {
24 acpi_handle handle;
25 u32 support_set;
26 u32 control_set;
27 int is_queried;
28 u32 query_result;
29 struct list_head sibiling;
31 static LIST_HEAD(acpi_osc_data_list);
33 struct acpi_osc_args {
34 u32 capbuf[3];
35 u32 query_result;
38 static struct acpi_osc_data *acpi_get_osc_data(acpi_handle handle)
40 struct acpi_osc_data *data;
42 list_for_each_entry(data, &acpi_osc_data_list, sibiling) {
43 if (data->handle == handle)
44 return data;
46 data = kzalloc(sizeof(*data), GFP_KERNEL);
47 if (!data)
48 return NULL;
49 INIT_LIST_HEAD(&data->sibiling);
50 data->handle = handle;
51 list_add_tail(&data->sibiling, &acpi_osc_data_list);
52 return data;
55 static u8 OSC_UUID[16] = {0x5B, 0x4D, 0xDB, 0x33, 0xF7, 0x1F, 0x1C, 0x40,
56 0x96, 0x57, 0x74, 0x41, 0xC0, 0x3D, 0xD7, 0x66};
58 static acpi_status acpi_run_osc(acpi_handle handle,
59 struct acpi_osc_args *osc_args)
61 acpi_status status;
62 struct acpi_object_list input;
63 union acpi_object in_params[4];
64 struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
65 union acpi_object *out_obj;
66 u32 osc_dw0, flags = osc_args->capbuf[OSC_QUERY_TYPE];
68 /* Setting up input parameters */
69 input.count = 4;
70 input.pointer = in_params;
71 in_params[0].type = ACPI_TYPE_BUFFER;
72 in_params[0].buffer.length = 16;
73 in_params[0].buffer.pointer = OSC_UUID;
74 in_params[1].type = ACPI_TYPE_INTEGER;
75 in_params[1].integer.value = 1;
76 in_params[2].type = ACPI_TYPE_INTEGER;
77 in_params[2].integer.value = 3;
78 in_params[3].type = ACPI_TYPE_BUFFER;
79 in_params[3].buffer.length = 12;
80 in_params[3].buffer.pointer = (u8 *)osc_args->capbuf;
82 status = acpi_evaluate_object(handle, "_OSC", &input, &output);
83 if (ACPI_FAILURE(status))
84 return status;
86 out_obj = output.pointer;
87 if (out_obj->type != ACPI_TYPE_BUFFER) {
88 printk(KERN_DEBUG "Evaluate _OSC returns wrong type\n");
89 status = AE_TYPE;
90 goto out_kfree;
92 osc_dw0 = *((u32 *)out_obj->buffer.pointer);
93 if (osc_dw0) {
94 if (osc_dw0 & OSC_REQUEST_ERROR)
95 printk(KERN_DEBUG "_OSC request fails\n");
96 if (osc_dw0 & OSC_INVALID_UUID_ERROR)
97 printk(KERN_DEBUG "_OSC invalid UUID\n");
98 if (osc_dw0 & OSC_INVALID_REVISION_ERROR)
99 printk(KERN_DEBUG "_OSC invalid revision\n");
100 if (osc_dw0 & OSC_CAPABILITIES_MASK_ERROR) {
101 if (flags & OSC_QUERY_ENABLE)
102 goto out_success;
103 printk(KERN_DEBUG "_OSC FW not grant req. control\n");
104 status = AE_SUPPORT;
105 goto out_kfree;
107 status = AE_ERROR;
108 goto out_kfree;
110 out_success:
111 if (flags & OSC_QUERY_ENABLE)
112 osc_args->query_result =
113 *((u32 *)(out_obj->buffer.pointer + 8));
114 status = AE_OK;
116 out_kfree:
117 kfree(output.pointer);
118 return status;
121 static acpi_status acpi_query_osc(acpi_handle handle,
122 u32 level, void *context, void **retval)
124 acpi_status status;
125 struct acpi_osc_data *osc_data;
126 u32 flags = (unsigned long)context, support_set;
127 acpi_handle tmp;
128 struct acpi_osc_args osc_args;
130 status = acpi_get_handle(handle, "_OSC", &tmp);
131 if (ACPI_FAILURE(status))
132 return status;
134 osc_data = acpi_get_osc_data(handle);
135 if (!osc_data) {
136 printk(KERN_ERR "acpi osc data array is full\n");
137 return AE_ERROR;
140 /* do _OSC query for all possible controls */
141 support_set = osc_data->support_set | (flags & OSC_SUPPORT_MASKS);
142 osc_args.capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
143 osc_args.capbuf[OSC_SUPPORT_TYPE] = support_set;
144 osc_args.capbuf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
146 status = acpi_run_osc(handle, &osc_args);
147 if (ACPI_SUCCESS(status)) {
148 osc_data->support_set = support_set;
149 osc_data->query_result = osc_args.query_result;
150 osc_data->is_queried = 1;
153 return status;
157 * __pci_osc_support_set - register OS support to Firmware
158 * @flags: OS support bits
159 * @hid: hardware ID
161 * Update OS support fields and doing a _OSC Query to obtain an update
162 * from Firmware on supported control bits.
164 acpi_status __pci_osc_support_set(u32 flags, const char *hid)
166 if (!(flags & OSC_SUPPORT_MASKS))
167 return AE_TYPE;
169 acpi_get_devices(hid, acpi_query_osc,
170 (void *)(unsigned long)flags, NULL);
171 return AE_OK;
175 * pci_osc_control_set - commit requested control to Firmware
176 * @handle: acpi_handle for the target ACPI object
177 * @flags: driver's requested control bits
179 * Attempt to take control from Firmware on requested control bits.
181 acpi_status pci_osc_control_set(acpi_handle handle, u32 flags)
183 acpi_status status;
184 u32 ctrlset, control_set;
185 acpi_handle tmp;
186 struct acpi_osc_data *osc_data;
187 struct acpi_osc_args osc_args;
189 status = acpi_get_handle(handle, "_OSC", &tmp);
190 if (ACPI_FAILURE(status))
191 return status;
193 osc_data = acpi_get_osc_data(handle);
194 if (!osc_data) {
195 printk(KERN_ERR "acpi osc data array is full\n");
196 return AE_ERROR;
199 ctrlset = (flags & OSC_CONTROL_MASKS);
200 if (!ctrlset)
201 return AE_TYPE;
203 if (osc_data->is_queried &&
204 ((osc_data->query_result & ctrlset) != ctrlset))
205 return AE_SUPPORT;
207 control_set = osc_data->control_set | ctrlset;
208 osc_args.capbuf[OSC_QUERY_TYPE] = 0;
209 osc_args.capbuf[OSC_SUPPORT_TYPE] = osc_data->support_set;
210 osc_args.capbuf[OSC_CONTROL_TYPE] = control_set;
211 status = acpi_run_osc(handle, &osc_args);
212 if (ACPI_SUCCESS(status))
213 osc_data->control_set = control_set;
215 return status;
217 EXPORT_SYMBOL(pci_osc_control_set);
220 * _SxD returns the D-state with the highest power
221 * (lowest D-state number) supported in the S-state "x".
223 * If the devices does not have a _PRW
224 * (Power Resources for Wake) supporting system wakeup from "x"
225 * then the OS is free to choose a lower power (higher number
226 * D-state) than the return value from _SxD.
228 * But if _PRW is enabled at S-state "x", the OS
229 * must not choose a power lower than _SxD --
230 * unless the device has an _SxW method specifying
231 * the lowest power (highest D-state number) the device
232 * may enter while still able to wake the system.
234 * ie. depending on global OS policy:
236 * if (_PRW at S-state x)
237 * choose from highest power _SxD to lowest power _SxW
238 * else // no _PRW at S-state x
239 * choose highest power _SxD or any lower power
242 static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev)
244 int acpi_state;
246 acpi_state = acpi_pm_device_sleep_state(&pdev->dev, NULL);
247 if (acpi_state < 0)
248 return PCI_POWER_ERROR;
250 switch (acpi_state) {
251 case ACPI_STATE_D0:
252 return PCI_D0;
253 case ACPI_STATE_D1:
254 return PCI_D1;
255 case ACPI_STATE_D2:
256 return PCI_D2;
257 case ACPI_STATE_D3:
258 return PCI_D3hot;
260 return PCI_POWER_ERROR;
263 static bool acpi_pci_power_manageable(struct pci_dev *dev)
265 acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
267 return handle ? acpi_bus_power_manageable(handle) : false;
270 static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
272 acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
273 acpi_handle tmp;
274 static const u8 state_conv[] = {
275 [PCI_D0] = ACPI_STATE_D0,
276 [PCI_D1] = ACPI_STATE_D1,
277 [PCI_D2] = ACPI_STATE_D2,
278 [PCI_D3hot] = ACPI_STATE_D3,
279 [PCI_D3cold] = ACPI_STATE_D3
281 int error = -EINVAL;
283 /* If the ACPI device has _EJ0, ignore the device */
284 if (!handle || ACPI_SUCCESS(acpi_get_handle(handle, "_EJ0", &tmp)))
285 return -ENODEV;
287 switch (state) {
288 case PCI_D0:
289 case PCI_D1:
290 case PCI_D2:
291 case PCI_D3hot:
292 case PCI_D3cold:
293 error = acpi_bus_set_power(handle, state_conv[state]);
296 if (!error)
297 dev_printk(KERN_INFO, &dev->dev,
298 "power state changed by ACPI to D%d\n", state);
300 return error;
303 static bool acpi_pci_can_wakeup(struct pci_dev *dev)
305 acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
307 return handle ? acpi_bus_can_wakeup(handle) : false;
310 static int acpi_pci_sleep_wake(struct pci_dev *dev, bool enable)
312 int error = acpi_pm_device_sleep_wake(&dev->dev, enable);
314 if (!error)
315 dev_printk(KERN_INFO, &dev->dev,
316 "wake-up capability %s by ACPI\n",
317 enable ? "enabled" : "disabled");
318 return error;
321 static struct pci_platform_pm_ops acpi_pci_platform_pm = {
322 .is_manageable = acpi_pci_power_manageable,
323 .set_state = acpi_pci_set_power_state,
324 .choose_state = acpi_pci_choose_state,
325 .can_wakeup = acpi_pci_can_wakeup,
326 .sleep_wake = acpi_pci_sleep_wake,
329 /* ACPI bus type */
330 static int acpi_pci_find_device(struct device *dev, acpi_handle *handle)
332 struct pci_dev * pci_dev;
333 acpi_integer addr;
335 pci_dev = to_pci_dev(dev);
336 /* Please ref to ACPI spec for the syntax of _ADR */
337 addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn);
338 *handle = acpi_get_child(DEVICE_ACPI_HANDLE(dev->parent), addr);
339 if (!*handle)
340 return -ENODEV;
341 return 0;
344 static int acpi_pci_find_root_bridge(struct device *dev, acpi_handle *handle)
346 int num;
347 unsigned int seg, bus;
350 * The string should be the same as root bridge's name
351 * Please look at 'pci_scan_bus_parented'
353 num = sscanf(dev->bus_id, "pci%04x:%02x", &seg, &bus);
354 if (num != 2)
355 return -ENODEV;
356 *handle = acpi_get_pci_rootbridge_handle(seg, bus);
357 if (!*handle)
358 return -ENODEV;
359 return 0;
362 static struct acpi_bus_type acpi_pci_bus = {
363 .bus = &pci_bus_type,
364 .find_device = acpi_pci_find_device,
365 .find_bridge = acpi_pci_find_root_bridge,
368 static int __init acpi_pci_init(void)
370 int ret;
372 if (acpi_gbl_FADT.boot_flags & BAF_MSI_NOT_SUPPORTED) {
373 printk(KERN_INFO"ACPI FADT declares the system doesn't support MSI, so disable it\n");
374 pci_no_msi();
377 if (acpi_gbl_FADT.boot_flags & BAF_PCIE_ASPM_CONTROL) {
378 printk(KERN_INFO"ACPI FADT declares the system doesn't support PCIe ASPM, so disable it\n");
379 pcie_no_aspm();
382 ret = register_acpi_bus_type(&acpi_pci_bus);
383 if (ret)
384 return 0;
385 pci_set_platform_pm(&acpi_pci_platform_pm);
386 return 0;
388 arch_initcall(acpi_pci_init);