pci_root.c revision 63f10f0f6df4e4e860b790d64bebfde85b540b0a 
1/*
2 *  pci_root.c - ACPI PCI Root Bridge Driver ($Revision: 40 $)
3 *
4 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
5 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
6 *
7 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
8 *
9 *  This program is free software; you can redistribute it and/or modify
10 *  it under the terms of the GNU General Public License as published by
11 *  the Free Software Foundation; either version 2 of the License, or (at
12 *  your option) any later version.
13 *
14 *  This program is distributed in the hope that it will be useful, but
15 *  WITHOUT ANY WARRANTY; without even the implied warranty of
16 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17 *  General Public License for more details.
18 *
19 *  You should have received a copy of the GNU General Public License along
20 *  with this program; if not, write to the Free Software Foundation, Inc.,
21 *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
22 *
23 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
24 */
25
26#include <linux/kernel.h>
27#include <linux/module.h>
28#include <linux/init.h>
29#include <linux/types.h>
30#include <linux/proc_fs.h>
31#include <linux/spinlock.h>
32#include <linux/pm.h>
33#include <linux/pci.h>
34#include <linux/pci-acpi.h>
35#include <linux/acpi.h>
36#include <acpi/acpi_bus.h>
37#include <acpi/acpi_drivers.h>
38
39#define _COMPONENT		ACPI_PCI_COMPONENT
40ACPI_MODULE_NAME("pci_root");
41#define ACPI_PCI_ROOT_CLASS		"pci_bridge"
42#define ACPI_PCI_ROOT_DEVICE_NAME	"PCI Root Bridge"
43static int acpi_pci_root_add(struct acpi_device *device);
44static int acpi_pci_root_remove(struct acpi_device *device, int type);
45static int acpi_pci_root_start(struct acpi_device *device);
46
47static struct acpi_device_id root_device_ids[] = {
48	{"PNP0A03", 0},
49	{"", 0},
50};
51MODULE_DEVICE_TABLE(acpi, root_device_ids);
52
53static struct acpi_driver acpi_pci_root_driver = {
54	.name = "pci_root",
55	.class = ACPI_PCI_ROOT_CLASS,
56	.ids = root_device_ids,
57	.ops = {
58		.add = acpi_pci_root_add,
59		.remove = acpi_pci_root_remove,
60		.start = acpi_pci_root_start,
61		},
62};
63
64struct acpi_pci_root {
65	struct list_head node;
66	struct acpi_device * device;
67	struct acpi_pci_id id;
68	struct pci_bus *bus;
69
70	u32 osc_support_set;	/* _OSC state of support bits */
71	u32 osc_control_set;	/* _OSC state of control bits */
72	u32 osc_control_qry;	/* the latest _OSC query result */
73
74	u32 osc_queried:1;	/* has _OSC control been queried? */
75};
76
77static LIST_HEAD(acpi_pci_roots);
78
79static struct acpi_pci_driver *sub_driver;
80static DEFINE_MUTEX(osc_lock);
81
82int acpi_pci_register_driver(struct acpi_pci_driver *driver)
83{
84	int n = 0;
85	struct list_head *entry;
86
87	struct acpi_pci_driver **pptr = &sub_driver;
88	while (*pptr)
89		pptr = &(*pptr)->next;
90	*pptr = driver;
91
92	if (!driver->add)
93		return 0;
94
95	list_for_each(entry, &acpi_pci_roots) {
96		struct acpi_pci_root *root;
97		root = list_entry(entry, struct acpi_pci_root, node);
98		driver->add(root->device->handle);
99		n++;
100	}
101
102	return n;
103}
104
105EXPORT_SYMBOL(acpi_pci_register_driver);
106
107void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
108{
109	struct list_head *entry;
110
111	struct acpi_pci_driver **pptr = &sub_driver;
112	while (*pptr) {
113		if (*pptr == driver)
114			break;
115		pptr = &(*pptr)->next;
116	}
117	BUG_ON(!*pptr);
118	*pptr = (*pptr)->next;
119
120	if (!driver->remove)
121		return;
122
123	list_for_each(entry, &acpi_pci_roots) {
124		struct acpi_pci_root *root;
125		root = list_entry(entry, struct acpi_pci_root, node);
126		driver->remove(root->device->handle);
127	}
128}
129
130EXPORT_SYMBOL(acpi_pci_unregister_driver);
131
132acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
133{
134	struct acpi_pci_root *tmp;
135
136	list_for_each_entry(tmp, &acpi_pci_roots, node) {
137		if ((tmp->id.segment == (u16) seg) && (tmp->id.bus == (u16) bus))
138			return tmp->device->handle;
139	}
140	return NULL;
141}
142
143EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
144
145static acpi_status
146get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
147{
148	int *busnr = data;
149	struct acpi_resource_address64 address;
150
151	if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
152	    resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
153	    resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
154		return AE_OK;
155
156	acpi_resource_to_address64(resource, &address);
157	if ((address.address_length > 0) &&
158	    (address.resource_type == ACPI_BUS_NUMBER_RANGE))
159		*busnr = address.minimum;
160
161	return AE_OK;
162}
163
164static acpi_status try_get_root_bridge_busnr(acpi_handle handle, int *busnum)
165{
166	acpi_status status;
167
168	*busnum = -1;
169	status =
170	    acpi_walk_resources(handle, METHOD_NAME__CRS,
171				get_root_bridge_busnr_callback, busnum);
172	if (ACPI_FAILURE(status))
173		return status;
174	/* Check if we really get a bus number from _CRS */
175	if (*busnum == -1)
176		return AE_ERROR;
177	return AE_OK;
178}
179
180static void acpi_pci_bridge_scan(struct acpi_device *device)
181{
182	int status;
183	struct acpi_device *child = NULL;
184
185	if (device->flags.bus_address)
186		if (device->parent && device->parent->ops.bind) {
187			status = device->parent->ops.bind(device);
188			if (!status) {
189				list_for_each_entry(child, &device->children, node)
190					acpi_pci_bridge_scan(child);
191			}
192		}
193}
194
195static u8 OSC_UUID[16] = {0x5B, 0x4D, 0xDB, 0x33, 0xF7, 0x1F, 0x1C, 0x40,
196			  0x96, 0x57, 0x74, 0x41, 0xC0, 0x3D, 0xD7, 0x66};
197
198static acpi_status acpi_pci_run_osc(acpi_handle handle,
199				    const u32 *capbuf, u32 *retval)
200{
201	acpi_status status;
202	struct acpi_object_list input;
203	union acpi_object in_params[4];
204	struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
205	union acpi_object *out_obj;
206	u32 errors;
207
208	/* Setting up input parameters */
209	input.count = 4;
210	input.pointer = in_params;
211	in_params[0].type 		= ACPI_TYPE_BUFFER;
212	in_params[0].buffer.length 	= 16;
213	in_params[0].buffer.pointer	= OSC_UUID;
214	in_params[1].type 		= ACPI_TYPE_INTEGER;
215	in_params[1].integer.value 	= 1;
216	in_params[2].type 		= ACPI_TYPE_INTEGER;
217	in_params[2].integer.value	= 3;
218	in_params[3].type		= ACPI_TYPE_BUFFER;
219	in_params[3].buffer.length 	= 12;
220	in_params[3].buffer.pointer 	= (u8 *)capbuf;
221
222	status = acpi_evaluate_object(handle, "_OSC", &input, &output);
223	if (ACPI_FAILURE(status))
224		return status;
225
226	if (!output.length)
227		return AE_NULL_OBJECT;
228
229	out_obj = output.pointer;
230	if (out_obj->type != ACPI_TYPE_BUFFER) {
231		printk(KERN_DEBUG "_OSC evaluation returned wrong type\n");
232		status = AE_TYPE;
233		goto out_kfree;
234	}
235	/* Need to ignore the bit0 in result code */
236	errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
237	if (errors) {
238		if (errors & OSC_REQUEST_ERROR)
239			printk(KERN_DEBUG "_OSC request failed\n");
240		if (errors & OSC_INVALID_UUID_ERROR)
241			printk(KERN_DEBUG "_OSC invalid UUID\n");
242		if (errors & OSC_INVALID_REVISION_ERROR)
243			printk(KERN_DEBUG "_OSC invalid revision\n");
244		if (errors & OSC_CAPABILITIES_MASK_ERROR) {
245			if (capbuf[OSC_QUERY_TYPE] & OSC_QUERY_ENABLE)
246				goto out_success;
247			printk(KERN_DEBUG
248			       "Firmware did not grant requested _OSC control\n");
249			status = AE_SUPPORT;
250			goto out_kfree;
251		}
252		status = AE_ERROR;
253		goto out_kfree;
254	}
255out_success:
256	*retval = *((u32 *)(out_obj->buffer.pointer + 8));
257	status = AE_OK;
258
259out_kfree:
260	kfree(output.pointer);
261	return status;
262}
263
264static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root, u32 flags)
265{
266	acpi_status status;
267	u32 support_set, result, capbuf[3];
268
269	/* do _OSC query for all possible controls */
270	support_set = root->osc_support_set | (flags & OSC_SUPPORT_MASKS);
271	capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
272	capbuf[OSC_SUPPORT_TYPE] = support_set;
273	capbuf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
274
275	status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
276	if (ACPI_SUCCESS(status)) {
277		root->osc_support_set = support_set;
278		root->osc_control_qry = result;
279		root->osc_queried = 1;
280	}
281	return status;
282}
283
284static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
285{
286	acpi_status status;
287	acpi_handle tmp;
288
289	status = acpi_get_handle(root->device->handle, "_OSC", &tmp);
290	if (ACPI_FAILURE(status))
291		return status;
292	mutex_lock(&osc_lock);
293	status = acpi_pci_query_osc(root, flags);
294	mutex_unlock(&osc_lock);
295	return status;
296}
297
298static struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
299{
300	struct acpi_pci_root *root;
301	list_for_each_entry(root, &acpi_pci_roots, node) {
302		if (root->device->handle == handle)
303			return root;
304	}
305	return NULL;
306}
307
308/**
309 * pci_osc_control_set - commit requested control to Firmware
310 * @handle: acpi_handle for the target ACPI object
311 * @flags: driver's requested control bits
312 *
313 * Attempt to take control from Firmware on requested control bits.
314 **/
315acpi_status pci_osc_control_set(acpi_handle handle, u32 flags)
316{
317	acpi_status status;
318	u32 control_req, result, capbuf[3];
319	acpi_handle tmp;
320	struct acpi_pci_root *root;
321
322	status = acpi_get_handle(handle, "_OSC", &tmp);
323	if (ACPI_FAILURE(status))
324		return status;
325
326	control_req = (flags & OSC_CONTROL_MASKS);
327	if (!control_req)
328		return AE_TYPE;
329
330	root = acpi_pci_find_root(handle);
331	if (!root)
332		return AE_NOT_EXIST;
333
334	mutex_lock(&osc_lock);
335	/* No need to evaluate _OSC if the control was already granted. */
336	if ((root->osc_control_set & control_req) == control_req)
337		goto out;
338
339	/* Need to query controls first before requesting them */
340	if (!root->osc_queried) {
341		status = acpi_pci_query_osc(root, root->osc_support_set);
342		if (ACPI_FAILURE(status))
343			goto out;
344	}
345	if ((root->osc_control_qry & control_req) != control_req) {
346		printk(KERN_DEBUG
347		       "Firmware did not grant requested _OSC control\n");
348		status = AE_SUPPORT;
349		goto out;
350	}
351
352	capbuf[OSC_QUERY_TYPE] = 0;
353	capbuf[OSC_SUPPORT_TYPE] = root->osc_support_set;
354	capbuf[OSC_CONTROL_TYPE] = root->osc_control_set | control_req;
355	status = acpi_pci_run_osc(handle, capbuf, &result);
356	if (ACPI_SUCCESS(status))
357		root->osc_control_set = result;
358out:
359	mutex_unlock(&osc_lock);
360	return status;
361}
362EXPORT_SYMBOL(pci_osc_control_set);
363
364static int __devinit acpi_pci_root_add(struct acpi_device *device)
365{
366	int result = 0;
367	struct acpi_pci_root *root = NULL;
368	struct acpi_pci_root *tmp;
369	acpi_status status = AE_OK;
370	unsigned long long value = 0;
371	acpi_handle handle = NULL;
372	struct acpi_device *child;
373	u32 flags, base_flags;
374
375
376	if (!device)
377		return -EINVAL;
378
379	root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
380	if (!root)
381		return -ENOMEM;
382	INIT_LIST_HEAD(&root->node);
383
384	root->device = device;
385	strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
386	strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
387	device->driver_data = root;
388
389	device->ops.bind = acpi_pci_bind;
390
391	/*
392	 * All supported architectures that use ACPI have support for
393	 * PCI domains, so we indicate this in _OSC support capabilities.
394	 */
395	flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
396	acpi_pci_osc_support(root, flags);
397
398	/*
399	 * Segment
400	 * -------
401	 * Obtained via _SEG, if exists, otherwise assumed to be zero (0).
402	 */
403	status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
404				       &value);
405	switch (status) {
406	case AE_OK:
407		root->id.segment = (u16) value;
408		break;
409	case AE_NOT_FOUND:
410		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
411				  "Assuming segment 0 (no _SEG)\n"));
412		root->id.segment = 0;
413		break;
414	default:
415		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _SEG"));
416		result = -ENODEV;
417		goto end;
418	}
419
420	/*
421	 * Bus
422	 * ---
423	 * Obtained via _BBN, if exists, otherwise assumed to be zero (0).
424	 */
425	status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN, NULL,
426				       &value);
427	switch (status) {
428	case AE_OK:
429		root->id.bus = (u16) value;
430		break;
431	case AE_NOT_FOUND:
432		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Assuming bus 0 (no _BBN)\n"));
433		root->id.bus = 0;
434		break;
435	default:
436		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BBN"));
437		result = -ENODEV;
438		goto end;
439	}
440
441	/* Some systems have wrong _BBN */
442	list_for_each_entry(tmp, &acpi_pci_roots, node) {
443		if ((tmp->id.segment == root->id.segment)
444		    && (tmp->id.bus == root->id.bus)) {
445			int bus = 0;
446			acpi_status status;
447
448			printk(KERN_ERR PREFIX
449				    "Wrong _BBN value, reboot"
450				    " and use option 'pci=noacpi'\n");
451
452			status = try_get_root_bridge_busnr(device->handle, &bus);
453			if (ACPI_FAILURE(status))
454				break;
455			if (bus != root->id.bus) {
456				printk(KERN_INFO PREFIX
457				       "PCI _CRS %d overrides _BBN 0\n", bus);
458				root->id.bus = bus;
459			}
460			break;
461		}
462	}
463	/*
464	 * Device & Function
465	 * -----------------
466	 * Obtained from _ADR (which has already been evaluated for us).
467	 */
468	root->id.device = device->pnp.bus_address >> 16;
469	root->id.function = device->pnp.bus_address & 0xFFFF;
470
471	/*
472	 * TBD: Need PCI interface for enumeration/configuration of roots.
473	 */
474
475	/* TBD: Locking */
476	list_add_tail(&root->node, &acpi_pci_roots);
477
478	printk(KERN_INFO PREFIX "%s [%s] (%04x:%02x)\n",
479	       acpi_device_name(device), acpi_device_bid(device),
480	       root->id.segment, root->id.bus);
481
482	/*
483	 * Scan the Root Bridge
484	 * --------------------
485	 * Must do this prior to any attempt to bind the root device, as the
486	 * PCI namespace does not get created until this call is made (and
487	 * thus the root bridge's pci_dev does not exist).
488	 */
489	root->bus = pci_acpi_scan_root(device, root->id.segment, root->id.bus);
490	if (!root->bus) {
491		printk(KERN_ERR PREFIX
492			    "Bus %04x:%02x not present in PCI namespace\n",
493			    root->id.segment, root->id.bus);
494		result = -ENODEV;
495		goto end;
496	}
497
498	/*
499	 * Attach ACPI-PCI Context
500	 * -----------------------
501	 * Thus binding the ACPI and PCI devices.
502	 */
503	result = acpi_pci_bind_root(device, &root->id, root->bus);
504	if (result)
505		goto end;
506
507	/*
508	 * PCI Routing Table
509	 * -----------------
510	 * Evaluate and parse _PRT, if exists.
511	 */
512	status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
513	if (ACPI_SUCCESS(status))
514		result = acpi_pci_irq_add_prt(device->handle, root->id.segment,
515					      root->id.bus);
516
517	/*
518	 * Scan and bind all _ADR-Based Devices
519	 */
520	list_for_each_entry(child, &device->children, node)
521		acpi_pci_bridge_scan(child);
522
523	/* Indicate support for various _OSC capabilities. */
524	if (pci_ext_cfg_avail(root->bus->self))
525		flags |= OSC_EXT_PCI_CONFIG_SUPPORT;
526	if (pcie_aspm_enabled())
527		flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
528			OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
529	if (pci_msi_enabled())
530		flags |= OSC_MSI_SUPPORT;
531	if (flags != base_flags)
532		acpi_pci_osc_support(root, flags);
533
534      end:
535	if (result) {
536		if (!list_empty(&root->node))
537			list_del(&root->node);
538		kfree(root);
539	}
540
541	return result;
542}
543
544static int acpi_pci_root_start(struct acpi_device *device)
545{
546	struct acpi_pci_root *root;
547
548
549	list_for_each_entry(root, &acpi_pci_roots, node) {
550		if (root->device == device) {
551			pci_bus_add_devices(root->bus);
552			return 0;
553		}
554	}
555	return -ENODEV;
556}
557
558static int acpi_pci_root_remove(struct acpi_device *device, int type)
559{
560	struct acpi_pci_root *root = NULL;
561
562
563	if (!device || !acpi_driver_data(device))
564		return -EINVAL;
565
566	root = acpi_driver_data(device);
567
568	kfree(root);
569
570	return 0;
571}
572
573static int __init acpi_pci_root_init(void)
574{
575	if (acpi_pci_disabled)
576		return 0;
577
578	if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
579		return -ENODEV;
580
581	return 0;
582}
583
584subsys_initcall(acpi_pci_root_init);
585