xref: /openbmc/linux/drivers/pci/pci-acpi.c (revision 22246614)
1 /*
2  * File:	pci-acpi.c
3  * Purpose:	Provide PCI support in ACPI
4  *
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  */
9 
10 #include <linux/delay.h>
11 #include <linux/init.h>
12 #include <linux/pci.h>
13 #include <linux/module.h>
14 #include <acpi/acpi.h>
15 #include <acpi/acnamesp.h>
16 #include <acpi/acresrc.h>
17 #include <acpi/acpi_bus.h>
18 
19 #include <linux/pci-acpi.h>
20 #include "pci.h"
21 
22 struct acpi_osc_data {
23 	acpi_handle handle;
24 	u32 ctrlset_buf[3];
25 	u32 global_ctrlsets;
26 	struct list_head sibiling;
27 };
28 static LIST_HEAD(acpi_osc_data_list);
29 
30 static struct acpi_osc_data *acpi_get_osc_data(acpi_handle handle)
31 {
32 	struct acpi_osc_data *data;
33 
34 	list_for_each_entry(data, &acpi_osc_data_list, sibiling) {
35 		if (data->handle == handle)
36 			return data;
37 	}
38 	data = kzalloc(sizeof(*data), GFP_KERNEL);
39 	if (!data)
40 		return NULL;
41 	INIT_LIST_HEAD(&data->sibiling);
42 	data->handle = handle;
43 	list_add_tail(&data->sibiling, &acpi_osc_data_list);
44 	return data;
45 }
46 
47 static u8 OSC_UUID[16] = {0x5B, 0x4D, 0xDB, 0x33, 0xF7, 0x1F, 0x1C, 0x40, 0x96, 0x57, 0x74, 0x41, 0xC0, 0x3D, 0xD7, 0x66};
48 
49 static acpi_status
50 acpi_query_osc (
51 	acpi_handle	handle,
52 	u32		level,
53 	void		*context,
54 	void		**retval )
55 {
56 	acpi_status		status;
57 	struct acpi_object_list	input;
58 	union acpi_object 	in_params[4];
59 	struct acpi_buffer	output = {ACPI_ALLOCATE_BUFFER, NULL};
60 	union acpi_object 	*out_obj;
61 	u32			osc_dw0;
62 	acpi_status *ret_status = (acpi_status *)retval;
63 	struct acpi_osc_data *osc_data;
64 	u32 flags = (unsigned long)context, temp;
65 	acpi_handle tmp;
66 
67 	status = acpi_get_handle(handle, "_OSC", &tmp);
68 	if (ACPI_FAILURE(status))
69 		return status;
70 
71 	osc_data = acpi_get_osc_data(handle);
72 	if (!osc_data) {
73 		printk(KERN_ERR "acpi osc data array is full\n");
74 		return AE_ERROR;
75 	}
76 
77 	osc_data->ctrlset_buf[OSC_SUPPORT_TYPE] |= (flags & OSC_SUPPORT_MASKS);
78 
79 	/* do _OSC query for all possible controls */
80 	temp = osc_data->ctrlset_buf[OSC_CONTROL_TYPE];
81 	osc_data->ctrlset_buf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
82 	osc_data->ctrlset_buf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
83 
84 	/* Setting up input parameters */
85 	input.count = 4;
86 	input.pointer = in_params;
87 	in_params[0].type 		= ACPI_TYPE_BUFFER;
88 	in_params[0].buffer.length 	= 16;
89 	in_params[0].buffer.pointer	= OSC_UUID;
90 	in_params[1].type 		= ACPI_TYPE_INTEGER;
91 	in_params[1].integer.value 	= 1;
92 	in_params[2].type 		= ACPI_TYPE_INTEGER;
93 	in_params[2].integer.value	= 3;
94 	in_params[3].type		= ACPI_TYPE_BUFFER;
95 	in_params[3].buffer.length 	= 12;
96 	in_params[3].buffer.pointer 	= (u8 *)osc_data->ctrlset_buf;
97 
98 	status = acpi_evaluate_object(handle, "_OSC", &input, &output);
99 	if (ACPI_FAILURE(status))
100 		goto out_nofree;
101 	out_obj = output.pointer;
102 
103 	if (out_obj->type != ACPI_TYPE_BUFFER) {
104 		printk(KERN_DEBUG
105 			"Evaluate _OSC returns wrong type\n");
106 		status = AE_TYPE;
107 		goto query_osc_out;
108 	}
109 	osc_dw0 = *((u32 *) out_obj->buffer.pointer);
110 	if (osc_dw0) {
111 		if (osc_dw0 & OSC_REQUEST_ERROR)
112 			printk(KERN_DEBUG "_OSC request fails\n");
113 		if (osc_dw0 & OSC_INVALID_UUID_ERROR)
114 			printk(KERN_DEBUG "_OSC invalid UUID\n");
115 		if (osc_dw0 & OSC_INVALID_REVISION_ERROR)
116 			printk(KERN_DEBUG "_OSC invalid revision\n");
117 		if (osc_dw0 & OSC_CAPABILITIES_MASK_ERROR) {
118 			/* Update Global Control Set */
119 			osc_data->global_ctrlsets =
120 				*((u32 *)(out_obj->buffer.pointer + 8));
121 			status = AE_OK;
122 			goto query_osc_out;
123 		}
124 		status = AE_ERROR;
125 		goto query_osc_out;
126 	}
127 
128 	/* Update Global Control Set */
129 	osc_data->global_ctrlsets = *((u32 *)(out_obj->buffer.pointer + 8));
130 	status = AE_OK;
131 
132 query_osc_out:
133 	kfree(output.pointer);
134 out_nofree:
135 	*ret_status = status;
136 
137 	osc_data->ctrlset_buf[OSC_QUERY_TYPE] = !OSC_QUERY_ENABLE;
138 	osc_data->ctrlset_buf[OSC_CONTROL_TYPE] = temp;
139 	if (ACPI_FAILURE(status)) {
140 		/* no osc support at all */
141 		osc_data->ctrlset_buf[OSC_SUPPORT_TYPE] = 0;
142 	}
143 
144 	return status;
145 }
146 
147 
148 static acpi_status
149 acpi_run_osc (
150 	acpi_handle	handle,
151 	void		*context)
152 {
153 	acpi_status		status;
154 	struct acpi_object_list	input;
155 	union acpi_object 	in_params[4];
156 	struct acpi_buffer	output = {ACPI_ALLOCATE_BUFFER, NULL};
157 	union acpi_object 	*out_obj;
158 	u32			osc_dw0;
159 
160 	/* Setting up input parameters */
161 	input.count = 4;
162 	input.pointer = in_params;
163 	in_params[0].type 		= ACPI_TYPE_BUFFER;
164 	in_params[0].buffer.length 	= 16;
165 	in_params[0].buffer.pointer	= OSC_UUID;
166 	in_params[1].type 		= ACPI_TYPE_INTEGER;
167 	in_params[1].integer.value 	= 1;
168 	in_params[2].type 		= ACPI_TYPE_INTEGER;
169 	in_params[2].integer.value	= 3;
170 	in_params[3].type		= ACPI_TYPE_BUFFER;
171 	in_params[3].buffer.length 	= 12;
172 	in_params[3].buffer.pointer 	= (u8 *)context;
173 
174 	status = acpi_evaluate_object(handle, "_OSC", &input, &output);
175 	if (ACPI_FAILURE (status))
176 		return status;
177 
178 	out_obj = output.pointer;
179 	if (out_obj->type != ACPI_TYPE_BUFFER) {
180 		printk(KERN_DEBUG
181 			"Evaluate _OSC returns wrong type\n");
182 		status = AE_TYPE;
183 		goto run_osc_out;
184 	}
185 	osc_dw0 = *((u32 *) out_obj->buffer.pointer);
186 	if (osc_dw0) {
187 		if (osc_dw0 & OSC_REQUEST_ERROR)
188 			printk(KERN_DEBUG "_OSC request fails\n");
189 		if (osc_dw0 & OSC_INVALID_UUID_ERROR)
190 			printk(KERN_DEBUG "_OSC invalid UUID\n");
191 		if (osc_dw0 & OSC_INVALID_REVISION_ERROR)
192 			printk(KERN_DEBUG "_OSC invalid revision\n");
193 		if (osc_dw0 & OSC_CAPABILITIES_MASK_ERROR) {
194 			printk(KERN_DEBUG "_OSC FW not grant req. control\n");
195 			status = AE_SUPPORT;
196 			goto run_osc_out;
197 		}
198 		status = AE_ERROR;
199 		goto run_osc_out;
200 	}
201 	status = AE_OK;
202 
203 run_osc_out:
204 	kfree(output.pointer);
205 	return status;
206 }
207 
208 /**
209  * __pci_osc_support_set - register OS support to Firmware
210  * @flags: OS support bits
211  * @hid: hardware ID
212  *
213  * Update OS support fields and doing a _OSC Query to obtain an update
214  * from Firmware on supported control bits.
215  **/
216 acpi_status __pci_osc_support_set(u32 flags, const char *hid)
217 {
218 	acpi_status retval = AE_NOT_FOUND;
219 
220 	if (!(flags & OSC_SUPPORT_MASKS)) {
221 		return AE_TYPE;
222 	}
223 	acpi_get_devices(hid,
224 			acpi_query_osc,
225 			(void *)(unsigned long)flags,
226 			(void **) &retval );
227 	return AE_OK;
228 }
229 
230 /**
231  * pci_osc_control_set - commit requested control to Firmware
232  * @handle: acpi_handle for the target ACPI object
233  * @flags: driver's requested control bits
234  *
235  * Attempt to take control from Firmware on requested control bits.
236  **/
237 acpi_status pci_osc_control_set(acpi_handle handle, u32 flags)
238 {
239 	acpi_status	status;
240 	u32		ctrlset;
241 	acpi_handle tmp;
242 	struct acpi_osc_data *osc_data;
243 
244 	status = acpi_get_handle(handle, "_OSC", &tmp);
245 	if (ACPI_FAILURE(status))
246 		return status;
247 
248 	osc_data = acpi_get_osc_data(handle);
249 	if (!osc_data) {
250 		printk(KERN_ERR "acpi osc data array is full\n");
251 		return AE_ERROR;
252 	}
253 
254 	ctrlset = (flags & OSC_CONTROL_MASKS);
255 	if (!ctrlset) {
256 		return AE_TYPE;
257 	}
258 	if (osc_data->ctrlset_buf[OSC_SUPPORT_TYPE] &&
259 		((osc_data->global_ctrlsets & ctrlset) != ctrlset)) {
260 		return AE_SUPPORT;
261 	}
262 	osc_data->ctrlset_buf[OSC_CONTROL_TYPE] |= ctrlset;
263 	status = acpi_run_osc(handle, osc_data->ctrlset_buf);
264 	if (ACPI_FAILURE (status)) {
265 		osc_data->ctrlset_buf[OSC_CONTROL_TYPE] &= ~ctrlset;
266 	}
267 
268 	return status;
269 }
270 EXPORT_SYMBOL(pci_osc_control_set);
271 
272 #ifdef CONFIG_ACPI_SLEEP
273 /*
274  * _SxD returns the D-state with the highest power
275  * (lowest D-state number) supported in the S-state "x".
276  *
277  * If the devices does not have a _PRW
278  * (Power Resources for Wake) supporting system wakeup from "x"
279  * then the OS is free to choose a lower power (higher number
280  * D-state) than the return value from _SxD.
281  *
282  * But if _PRW is enabled at S-state "x", the OS
283  * must not choose a power lower than _SxD --
284  * unless the device has an _SxW method specifying
285  * the lowest power (highest D-state number) the device
286  * may enter while still able to wake the system.
287  *
288  * ie. depending on global OS policy:
289  *
290  * if (_PRW at S-state x)
291  *	choose from highest power _SxD to lowest power _SxW
292  * else // no _PRW at S-state x
293  * 	choose highest power _SxD or any lower power
294  */
295 
296 static pci_power_t acpi_pci_choose_state(struct pci_dev *pdev,
297 	pm_message_t state)
298 {
299 	int acpi_state;
300 
301 	acpi_state = acpi_pm_device_sleep_state(&pdev->dev,
302 		device_may_wakeup(&pdev->dev), NULL);
303 	if (acpi_state < 0)
304 		return PCI_POWER_ERROR;
305 
306 	switch (acpi_state) {
307 	case ACPI_STATE_D0:
308 		return PCI_D0;
309 	case ACPI_STATE_D1:
310 		return PCI_D1;
311 	case ACPI_STATE_D2:
312 		return PCI_D2;
313 	case ACPI_STATE_D3:
314 		return PCI_D3hot;
315 	}
316 	return PCI_POWER_ERROR;
317 }
318 #endif
319 
320 static int acpi_pci_set_power_state(struct pci_dev *dev, pci_power_t state)
321 {
322 	acpi_handle handle = DEVICE_ACPI_HANDLE(&dev->dev);
323 	acpi_handle tmp;
324 	static const u8 state_conv[] = {
325 		[PCI_D0] = ACPI_STATE_D0,
326 		[PCI_D1] = ACPI_STATE_D1,
327 		[PCI_D2] = ACPI_STATE_D2,
328 		[PCI_D3hot] = ACPI_STATE_D3,
329 		[PCI_D3cold] = ACPI_STATE_D3
330 	};
331 
332 	if (!handle)
333 		return -ENODEV;
334 	/* If the ACPI device has _EJ0, ignore the device */
335 	if (ACPI_SUCCESS(acpi_get_handle(handle, "_EJ0", &tmp)))
336 		return 0;
337 
338 	switch (state) {
339 	case PCI_D0:
340 	case PCI_D1:
341 	case PCI_D2:
342 	case PCI_D3hot:
343 	case PCI_D3cold:
344 		return acpi_bus_set_power(handle, state_conv[state]);
345 	}
346 	return -EINVAL;
347 }
348 
349 
350 /* ACPI bus type */
351 static int acpi_pci_find_device(struct device *dev, acpi_handle *handle)
352 {
353 	struct pci_dev * pci_dev;
354 	acpi_integer	addr;
355 
356 	pci_dev = to_pci_dev(dev);
357 	/* Please ref to ACPI spec for the syntax of _ADR */
358 	addr = (PCI_SLOT(pci_dev->devfn) << 16) | PCI_FUNC(pci_dev->devfn);
359 	*handle = acpi_get_child(DEVICE_ACPI_HANDLE(dev->parent), addr);
360 	if (!*handle)
361 		return -ENODEV;
362 	return 0;
363 }
364 
365 static int acpi_pci_find_root_bridge(struct device *dev, acpi_handle *handle)
366 {
367 	int num;
368 	unsigned int seg, bus;
369 
370 	/*
371 	 * The string should be the same as root bridge's name
372 	 * Please look at 'pci_scan_bus_parented'
373 	 */
374 	num = sscanf(dev->bus_id, "pci%04x:%02x", &seg, &bus);
375 	if (num != 2)
376 		return -ENODEV;
377 	*handle = acpi_get_pci_rootbridge_handle(seg, bus);
378 	if (!*handle)
379 		return -ENODEV;
380 	return 0;
381 }
382 
383 static struct acpi_bus_type acpi_pci_bus = {
384 	.bus = &pci_bus_type,
385 	.find_device = acpi_pci_find_device,
386 	.find_bridge = acpi_pci_find_root_bridge,
387 };
388 
389 static int __init acpi_pci_init(void)
390 {
391 	int ret;
392 
393 	if (acpi_gbl_FADT.boot_flags & BAF_MSI_NOT_SUPPORTED) {
394 		printk(KERN_INFO"ACPI FADT declares the system doesn't support MSI, so disable it\n");
395 		pci_no_msi();
396 	}
397 	ret = register_acpi_bus_type(&acpi_pci_bus);
398 	if (ret)
399 		return 0;
400 #ifdef	CONFIG_ACPI_SLEEP
401 	platform_pci_choose_state = acpi_pci_choose_state;
402 #endif
403 	platform_pci_set_power_state = acpi_pci_set_power_state;
404 	return 0;
405 }
406 arch_initcall(acpi_pci_init);
407