pci_root.c revision 003d6a38ce1a59e0053a02fd9e9a65b588bc8e33 
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 PREFIX "ACPI: "
40
41#define _COMPONENT		ACPI_PCI_COMPONENT
42ACPI_MODULE_NAME("pci_root");
43#define ACPI_PCI_ROOT_CLASS		"pci_bridge"
44#define ACPI_PCI_ROOT_DEVICE_NAME	"PCI Root Bridge"
45static int acpi_pci_root_add(struct acpi_device *device);
46static int acpi_pci_root_remove(struct acpi_device *device, int type);
47static int acpi_pci_root_start(struct acpi_device *device);
48
49static struct acpi_device_id root_device_ids[] = {
50	{"PNP0A03", 0},
51	{"", 0},
52};
53MODULE_DEVICE_TABLE(acpi, root_device_ids);
54
55static struct acpi_driver acpi_pci_root_driver = {
56	.name = "pci_root",
57	.class = ACPI_PCI_ROOT_CLASS,
58	.ids = root_device_ids,
59	.ops = {
60		.add = acpi_pci_root_add,
61		.remove = acpi_pci_root_remove,
62		.start = acpi_pci_root_start,
63		},
64};
65
66static LIST_HEAD(acpi_pci_roots);
67
68static struct acpi_pci_driver *sub_driver;
69static DEFINE_MUTEX(osc_lock);
70
71int acpi_pci_register_driver(struct acpi_pci_driver *driver)
72{
73	int n = 0;
74	struct acpi_pci_root *root;
75
76	struct acpi_pci_driver **pptr = &sub_driver;
77	while (*pptr)
78		pptr = &(*pptr)->next;
79	*pptr = driver;
80
81	if (!driver->add)
82		return 0;
83
84	list_for_each_entry(root, &acpi_pci_roots, node) {
85		driver->add(root->device->handle);
86		n++;
87	}
88
89	return n;
90}
91
92EXPORT_SYMBOL(acpi_pci_register_driver);
93
94void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
95{
96	struct acpi_pci_root *root;
97
98	struct acpi_pci_driver **pptr = &sub_driver;
99	while (*pptr) {
100		if (*pptr == driver)
101			break;
102		pptr = &(*pptr)->next;
103	}
104	BUG_ON(!*pptr);
105	*pptr = (*pptr)->next;
106
107	if (!driver->remove)
108		return;
109
110	list_for_each_entry(root, &acpi_pci_roots, node)
111		driver->remove(root->device->handle);
112}
113
114EXPORT_SYMBOL(acpi_pci_unregister_driver);
115
116acpi_handle acpi_get_pci_rootbridge_handle(unsigned int seg, unsigned int bus)
117{
118	struct acpi_pci_root *root;
119
120	list_for_each_entry(root, &acpi_pci_roots, node)
121		if ((root->segment == (u16) seg) && (root->bus_nr == (u16) bus))
122			return root->device->handle;
123	return NULL;
124}
125
126EXPORT_SYMBOL_GPL(acpi_get_pci_rootbridge_handle);
127
128/**
129 * acpi_is_root_bridge - determine whether an ACPI CA node is a PCI root bridge
130 * @handle - the ACPI CA node in question.
131 *
132 * Note: we could make this API take a struct acpi_device * instead, but
133 * for now, it's more convenient to operate on an acpi_handle.
134 */
135int acpi_is_root_bridge(acpi_handle handle)
136{
137	int ret;
138	struct acpi_device *device;
139
140	ret = acpi_bus_get_device(handle, &device);
141	if (ret)
142		return 0;
143
144	ret = acpi_match_device_ids(device, root_device_ids);
145	if (ret)
146		return 0;
147	else
148		return 1;
149}
150EXPORT_SYMBOL_GPL(acpi_is_root_bridge);
151
152static acpi_status
153get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
154{
155	int *busnr = data;
156	struct acpi_resource_address64 address;
157
158	if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
159	    resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
160	    resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
161		return AE_OK;
162
163	acpi_resource_to_address64(resource, &address);
164	if ((address.address_length > 0) &&
165	    (address.resource_type == ACPI_BUS_NUMBER_RANGE))
166		*busnr = address.minimum;
167
168	return AE_OK;
169}
170
171static acpi_status try_get_root_bridge_busnr(acpi_handle handle,
172					     unsigned long long *bus)
173{
174	acpi_status status;
175	int busnum;
176
177	busnum = -1;
178	status =
179	    acpi_walk_resources(handle, METHOD_NAME__CRS,
180				get_root_bridge_busnr_callback, &busnum);
181	if (ACPI_FAILURE(status))
182		return status;
183	/* Check if we really get a bus number from _CRS */
184	if (busnum == -1)
185		return AE_ERROR;
186	*bus = busnum;
187	return AE_OK;
188}
189
190static void acpi_pci_bridge_scan(struct acpi_device *device)
191{
192	int status;
193	struct acpi_device *child = NULL;
194
195	if (device->flags.bus_address)
196		if (device->parent && device->parent->ops.bind) {
197			status = device->parent->ops.bind(device);
198			if (!status) {
199				list_for_each_entry(child, &device->children, node)
200					acpi_pci_bridge_scan(child);
201			}
202		}
203}
204
205static u8 OSC_UUID[16] = {0x5B, 0x4D, 0xDB, 0x33, 0xF7, 0x1F, 0x1C, 0x40,
206			  0x96, 0x57, 0x74, 0x41, 0xC0, 0x3D, 0xD7, 0x66};
207
208static acpi_status acpi_pci_run_osc(acpi_handle handle,
209				    const u32 *capbuf, u32 *retval)
210{
211	acpi_status status;
212	struct acpi_object_list input;
213	union acpi_object in_params[4];
214	struct acpi_buffer output = {ACPI_ALLOCATE_BUFFER, NULL};
215	union acpi_object *out_obj;
216	u32 errors;
217
218	/* Setting up input parameters */
219	input.count = 4;
220	input.pointer = in_params;
221	in_params[0].type 		= ACPI_TYPE_BUFFER;
222	in_params[0].buffer.length 	= 16;
223	in_params[0].buffer.pointer	= OSC_UUID;
224	in_params[1].type 		= ACPI_TYPE_INTEGER;
225	in_params[1].integer.value 	= 1;
226	in_params[2].type 		= ACPI_TYPE_INTEGER;
227	in_params[2].integer.value	= 3;
228	in_params[3].type		= ACPI_TYPE_BUFFER;
229	in_params[3].buffer.length 	= 12;
230	in_params[3].buffer.pointer 	= (u8 *)capbuf;
231
232	status = acpi_evaluate_object(handle, "_OSC", &input, &output);
233	if (ACPI_FAILURE(status))
234		return status;
235
236	if (!output.length)
237		return AE_NULL_OBJECT;
238
239	out_obj = output.pointer;
240	if (out_obj->type != ACPI_TYPE_BUFFER) {
241		printk(KERN_DEBUG "_OSC evaluation returned wrong type\n");
242		status = AE_TYPE;
243		goto out_kfree;
244	}
245	/* Need to ignore the bit0 in result code */
246	errors = *((u32 *)out_obj->buffer.pointer) & ~(1 << 0);
247	if (errors) {
248		if (errors & OSC_REQUEST_ERROR)
249			printk(KERN_DEBUG "_OSC request failed\n");
250		if (errors & OSC_INVALID_UUID_ERROR)
251			printk(KERN_DEBUG "_OSC invalid UUID\n");
252		if (errors & OSC_INVALID_REVISION_ERROR)
253			printk(KERN_DEBUG "_OSC invalid revision\n");
254		if (errors & OSC_CAPABILITIES_MASK_ERROR) {
255			if (capbuf[OSC_QUERY_TYPE] & OSC_QUERY_ENABLE)
256				goto out_success;
257			printk(KERN_DEBUG
258			       "Firmware did not grant requested _OSC control\n");
259			status = AE_SUPPORT;
260			goto out_kfree;
261		}
262		status = AE_ERROR;
263		goto out_kfree;
264	}
265out_success:
266	*retval = *((u32 *)(out_obj->buffer.pointer + 8));
267	status = AE_OK;
268
269out_kfree:
270	kfree(output.pointer);
271	return status;
272}
273
274static acpi_status acpi_pci_query_osc(struct acpi_pci_root *root, u32 flags)
275{
276	acpi_status status;
277	u32 support_set, result, capbuf[3];
278
279	/* do _OSC query for all possible controls */
280	support_set = root->osc_support_set | (flags & OSC_SUPPORT_MASKS);
281	capbuf[OSC_QUERY_TYPE] = OSC_QUERY_ENABLE;
282	capbuf[OSC_SUPPORT_TYPE] = support_set;
283	capbuf[OSC_CONTROL_TYPE] = OSC_CONTROL_MASKS;
284
285	status = acpi_pci_run_osc(root->device->handle, capbuf, &result);
286	if (ACPI_SUCCESS(status)) {
287		root->osc_support_set = support_set;
288		root->osc_control_qry = result;
289		root->osc_queried = 1;
290	}
291	return status;
292}
293
294static acpi_status acpi_pci_osc_support(struct acpi_pci_root *root, u32 flags)
295{
296	acpi_status status;
297	acpi_handle tmp;
298
299	status = acpi_get_handle(root->device->handle, "_OSC", &tmp);
300	if (ACPI_FAILURE(status))
301		return status;
302	mutex_lock(&osc_lock);
303	status = acpi_pci_query_osc(root, flags);
304	mutex_unlock(&osc_lock);
305	return status;
306}
307
308struct acpi_pci_root *acpi_pci_find_root(acpi_handle handle)
309{
310	struct acpi_pci_root *root;
311
312	list_for_each_entry(root, &acpi_pci_roots, node) {
313		if (root->device->handle == handle)
314			return root;
315	}
316	return NULL;
317}
318EXPORT_SYMBOL_GPL(acpi_pci_find_root);
319
320struct acpi_handle_node {
321	struct list_head node;
322	acpi_handle handle;
323};
324
325/**
326 * acpi_get_pci_dev - convert ACPI CA handle to struct pci_dev
327 * @handle: the handle in question
328 *
329 * Given an ACPI CA handle, the desired PCI device is located in the
330 * list of PCI devices.
331 *
332 * If the device is found, its reference count is increased and this
333 * function returns a pointer to its data structure.  The caller must
334 * decrement the reference count by calling pci_dev_put().
335 * If no device is found, %NULL is returned.
336 */
337struct pci_dev *acpi_get_pci_dev(acpi_handle handle)
338{
339	int dev, fn;
340	unsigned long long adr;
341	acpi_status status;
342	acpi_handle phandle;
343	struct pci_bus *pbus;
344	struct pci_dev *pdev = NULL;
345	struct acpi_handle_node *node, *tmp;
346	struct acpi_pci_root *root;
347	LIST_HEAD(device_list);
348
349	/*
350	 * Walk up the ACPI CA namespace until we reach a PCI root bridge.
351	 */
352	phandle = handle;
353	while (!acpi_is_root_bridge(phandle)) {
354		node = kzalloc(sizeof(struct acpi_handle_node), GFP_KERNEL);
355		if (!node)
356			goto out;
357
358		INIT_LIST_HEAD(&node->node);
359		node->handle = phandle;
360		list_add(&node->node, &device_list);
361
362		status = acpi_get_parent(phandle, &phandle);
363		if (ACPI_FAILURE(status))
364			goto out;
365	}
366
367	root = acpi_pci_find_root(phandle);
368	if (!root)
369		goto out;
370
371	pbus = root->bus;
372
373	/*
374	 * Now, walk back down the PCI device tree until we return to our
375	 * original handle. Assumes that everything between the PCI root
376	 * bridge and the device we're looking for must be a P2P bridge.
377	 */
378	list_for_each_entry(node, &device_list, node) {
379		acpi_handle hnd = node->handle;
380		status = acpi_evaluate_integer(hnd, "_ADR", NULL, &adr);
381		if (ACPI_FAILURE(status))
382			goto out;
383		dev = (adr >> 16) & 0xffff;
384		fn  = adr & 0xffff;
385
386		pdev = pci_get_slot(pbus, PCI_DEVFN(dev, fn));
387		if (!pdev || hnd == handle)
388			break;
389
390		pbus = pdev->subordinate;
391		pci_dev_put(pdev);
392	}
393out:
394	list_for_each_entry_safe(node, tmp, &device_list, node)
395		kfree(node);
396
397	return pdev;
398}
399EXPORT_SYMBOL_GPL(acpi_get_pci_dev);
400
401/**
402 * acpi_pci_osc_control_set - commit requested control to Firmware
403 * @handle: acpi_handle for the target ACPI object
404 * @flags: driver's requested control bits
405 *
406 * Attempt to take control from Firmware on requested control bits.
407 **/
408acpi_status acpi_pci_osc_control_set(acpi_handle handle, u32 flags)
409{
410	acpi_status status;
411	u32 control_req, result, capbuf[3];
412	acpi_handle tmp;
413	struct acpi_pci_root *root;
414
415	status = acpi_get_handle(handle, "_OSC", &tmp);
416	if (ACPI_FAILURE(status))
417		return status;
418
419	control_req = (flags & OSC_CONTROL_MASKS);
420	if (!control_req)
421		return AE_TYPE;
422
423	root = acpi_pci_find_root(handle);
424	if (!root)
425		return AE_NOT_EXIST;
426
427	mutex_lock(&osc_lock);
428	/* No need to evaluate _OSC if the control was already granted. */
429	if ((root->osc_control_set & control_req) == control_req)
430		goto out;
431
432	/* Need to query controls first before requesting them */
433	if (!root->osc_queried) {
434		status = acpi_pci_query_osc(root, root->osc_support_set);
435		if (ACPI_FAILURE(status))
436			goto out;
437	}
438	if ((root->osc_control_qry & control_req) != control_req) {
439		printk(KERN_DEBUG
440		       "Firmware did not grant requested _OSC control\n");
441		status = AE_SUPPORT;
442		goto out;
443	}
444
445	capbuf[OSC_QUERY_TYPE] = 0;
446	capbuf[OSC_SUPPORT_TYPE] = root->osc_support_set;
447	capbuf[OSC_CONTROL_TYPE] = root->osc_control_set | control_req;
448	status = acpi_pci_run_osc(handle, capbuf, &result);
449	if (ACPI_SUCCESS(status))
450		root->osc_control_set = result;
451out:
452	mutex_unlock(&osc_lock);
453	return status;
454}
455EXPORT_SYMBOL(acpi_pci_osc_control_set);
456
457static int __devinit acpi_pci_root_add(struct acpi_device *device)
458{
459	unsigned long long segment, bus;
460	acpi_status status;
461	int result;
462	struct acpi_pci_root *root;
463	acpi_handle handle;
464	struct acpi_device *child;
465	u32 flags, base_flags;
466
467	segment = 0;
468	status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
469				       &segment);
470	if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
471		printk(KERN_ERR PREFIX "can't evaluate _SEG\n");
472		return -ENODEV;
473	}
474
475	/* Check _CRS first, then _BBN.  If no _BBN, default to zero. */
476	bus = 0;
477	status = try_get_root_bridge_busnr(device->handle, &bus);
478	if (ACPI_FAILURE(status)) {
479		status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN,					       NULL, &bus);
480		if (ACPI_FAILURE(status) && status != AE_NOT_FOUND) {
481			printk(KERN_ERR PREFIX
482			     "no bus number in _CRS and can't evaluate _BBN\n");
483			return -ENODEV;
484		}
485	}
486
487	root = kzalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
488	if (!root)
489		return -ENOMEM;
490
491	INIT_LIST_HEAD(&root->node);
492	root->device = device;
493	root->segment = segment & 0xFFFF;
494	root->bus_nr = bus & 0xFF;
495	strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
496	strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
497	device->driver_data = root;
498
499	/*
500	 * All supported architectures that use ACPI have support for
501	 * PCI domains, so we indicate this in _OSC support capabilities.
502	 */
503	flags = base_flags = OSC_PCI_SEGMENT_GROUPS_SUPPORT;
504	acpi_pci_osc_support(root, flags);
505
506	/*
507	 * TBD: Need PCI interface for enumeration/configuration of roots.
508	 */
509
510	/* TBD: Locking */
511	list_add_tail(&root->node, &acpi_pci_roots);
512
513	printk(KERN_INFO PREFIX "%s [%s] (%04x:%02x)\n",
514	       acpi_device_name(device), acpi_device_bid(device),
515	       root->segment, root->bus_nr);
516
517	/*
518	 * Scan the Root Bridge
519	 * --------------------
520	 * Must do this prior to any attempt to bind the root device, as the
521	 * PCI namespace does not get created until this call is made (and
522	 * thus the root bridge's pci_dev does not exist).
523	 */
524	root->bus = pci_acpi_scan_root(device, segment, bus);
525	if (!root->bus) {
526		printk(KERN_ERR PREFIX
527			    "Bus %04x:%02x not present in PCI namespace\n",
528			    root->segment, root->bus_nr);
529		result = -ENODEV;
530		goto end;
531	}
532
533	/*
534	 * Attach ACPI-PCI Context
535	 * -----------------------
536	 * Thus binding the ACPI and PCI devices.
537	 */
538	result = acpi_pci_bind_root(device);
539	if (result)
540		goto end;
541
542	/*
543	 * PCI Routing Table
544	 * -----------------
545	 * Evaluate and parse _PRT, if exists.
546	 */
547	status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
548	if (ACPI_SUCCESS(status))
549		result = acpi_pci_irq_add_prt(device->handle, root->bus);
550
551	/*
552	 * Scan and bind all _ADR-Based Devices
553	 */
554	list_for_each_entry(child, &device->children, node)
555		acpi_pci_bridge_scan(child);
556
557	/* Indicate support for various _OSC capabilities. */
558	if (pci_ext_cfg_avail(root->bus->self))
559		flags |= OSC_EXT_PCI_CONFIG_SUPPORT;
560	if (pcie_aspm_enabled())
561		flags |= OSC_ACTIVE_STATE_PWR_SUPPORT |
562			OSC_CLOCK_PWR_CAPABILITY_SUPPORT;
563	if (pci_msi_enabled())
564		flags |= OSC_MSI_SUPPORT;
565	if (flags != base_flags)
566		acpi_pci_osc_support(root, flags);
567
568	return 0;
569
570end:
571	if (!list_empty(&root->node))
572		list_del(&root->node);
573	kfree(root);
574	return result;
575}
576
577static int acpi_pci_root_start(struct acpi_device *device)
578{
579	struct acpi_pci_root *root = acpi_driver_data(device);
580
581	pci_bus_add_devices(root->bus);
582	return 0;
583}
584
585static int acpi_pci_root_remove(struct acpi_device *device, int type)
586{
587	struct acpi_pci_root *root = acpi_driver_data(device);
588
589	kfree(root);
590	return 0;
591}
592
593static int __init acpi_pci_root_init(void)
594{
595	if (acpi_pci_disabled)
596		return 0;
597
598	if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
599		return -ENODEV;
600
601	return 0;
602}
603
604subsys_initcall(acpi_pci_root_init);
605