pci_root.c revision f10bb2544bab75b3e8df15a7b51a833c78cbd77f 
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/acpi.h>
35#include <acpi/acpi_bus.h>
36#include <acpi/acpi_drivers.h>
37
38#define _COMPONENT		ACPI_PCI_COMPONENT
39ACPI_MODULE_NAME("pci_root")
40#define ACPI_PCI_ROOT_CLASS		"pci_bridge"
41#define ACPI_PCI_ROOT_HID		"PNP0A03"
42#define ACPI_PCI_ROOT_DRIVER_NAME	"ACPI PCI Root Bridge Driver"
43#define ACPI_PCI_ROOT_DEVICE_NAME	"PCI Root Bridge"
44static int acpi_pci_root_add(struct acpi_device *device);
45static int acpi_pci_root_remove(struct acpi_device *device, int type);
46static int acpi_pci_root_start(struct acpi_device *device);
47
48static struct acpi_driver acpi_pci_root_driver = {
49	.name = ACPI_PCI_ROOT_DRIVER_NAME,
50	.class = ACPI_PCI_ROOT_CLASS,
51	.ids = ACPI_PCI_ROOT_HID,
52	.ops = {
53		.add = acpi_pci_root_add,
54		.remove = acpi_pci_root_remove,
55		.start = acpi_pci_root_start,
56		},
57};
58
59struct acpi_pci_root {
60	struct list_head node;
61	struct acpi_device * device;
62	struct acpi_pci_id id;
63	struct pci_bus *bus;
64};
65
66static LIST_HEAD(acpi_pci_roots);
67
68static struct acpi_pci_driver *sub_driver;
69
70int acpi_pci_register_driver(struct acpi_pci_driver *driver)
71{
72	int n = 0;
73	struct list_head *entry;
74
75	struct acpi_pci_driver **pptr = &sub_driver;
76	while (*pptr)
77		pptr = &(*pptr)->next;
78	*pptr = driver;
79
80	if (!driver->add)
81		return 0;
82
83	list_for_each(entry, &acpi_pci_roots) {
84		struct acpi_pci_root *root;
85		root = list_entry(entry, struct acpi_pci_root, node);
86		driver->add(root->device->handle);
87		n++;
88	}
89
90	return n;
91}
92
93EXPORT_SYMBOL(acpi_pci_register_driver);
94
95void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
96{
97	struct list_head *entry;
98
99	struct acpi_pci_driver **pptr = &sub_driver;
100	while (*pptr) {
101		if (*pptr == driver)
102			break;
103		pptr = &(*pptr)->next;
104	}
105	BUG_ON(!*pptr);
106	*pptr = (*pptr)->next;
107
108	if (!driver->remove)
109		return;
110
111	list_for_each(entry, &acpi_pci_roots) {
112		struct acpi_pci_root *root;
113		root = list_entry(entry, struct acpi_pci_root, node);
114		driver->remove(root->device->handle);
115	}
116}
117
118EXPORT_SYMBOL(acpi_pci_unregister_driver);
119
120static acpi_status
121get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
122{
123	int *busnr = (int *)data;
124	struct acpi_resource_address64 address;
125
126	if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
127	    resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
128	    resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
129		return AE_OK;
130
131	acpi_resource_to_address64(resource, &address);
132	if ((address.address_length > 0) &&
133	    (address.resource_type == ACPI_BUS_NUMBER_RANGE))
134		*busnr = address.minimum;
135
136	return AE_OK;
137}
138
139static acpi_status try_get_root_bridge_busnr(acpi_handle handle, int *busnum)
140{
141	acpi_status status;
142
143	*busnum = -1;
144	status =
145	    acpi_walk_resources(handle, METHOD_NAME__CRS,
146				get_root_bridge_busnr_callback, busnum);
147	if (ACPI_FAILURE(status))
148		return status;
149	/* Check if we really get a bus number from _CRS */
150	if (*busnum == -1)
151		return AE_ERROR;
152	return AE_OK;
153}
154
155static int acpi_pci_root_add(struct acpi_device *device)
156{
157	int result = 0;
158	struct acpi_pci_root *root = NULL;
159	struct acpi_pci_root *tmp;
160	acpi_status status = AE_OK;
161	unsigned long value = 0;
162	acpi_handle handle = NULL;
163
164
165	if (!device)
166		return -EINVAL;
167
168	root = kmalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
169	if (!root)
170		return -ENOMEM;
171	memset(root, 0, sizeof(struct acpi_pci_root));
172	INIT_LIST_HEAD(&root->node);
173
174	root->device = device;
175	strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
176	strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
177	acpi_driver_data(device) = root;
178
179	/*
180	 * TBD: Doesn't the bus driver automatically set this?
181	 */
182	device->ops.bind = acpi_pci_bind;
183
184	/*
185	 * Segment
186	 * -------
187	 * Obtained via _SEG, if exists, otherwise assumed to be zero (0).
188	 */
189	status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
190				       &value);
191	switch (status) {
192	case AE_OK:
193		root->id.segment = (u16) value;
194		break;
195	case AE_NOT_FOUND:
196		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
197				  "Assuming segment 0 (no _SEG)\n"));
198		root->id.segment = 0;
199		break;
200	default:
201		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _SEG"));
202		result = -ENODEV;
203		goto end;
204	}
205
206	/*
207	 * Bus
208	 * ---
209	 * Obtained via _BBN, if exists, otherwise assumed to be zero (0).
210	 */
211	status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN, NULL,
212				       &value);
213	switch (status) {
214	case AE_OK:
215		root->id.bus = (u16) value;
216		break;
217	case AE_NOT_FOUND:
218		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Assuming bus 0 (no _BBN)\n"));
219		root->id.bus = 0;
220		break;
221	default:
222		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BBN"));
223		result = -ENODEV;
224		goto end;
225	}
226
227	/* Some systems have wrong _BBN */
228	list_for_each_entry(tmp, &acpi_pci_roots, node) {
229		if ((tmp->id.segment == root->id.segment)
230		    && (tmp->id.bus == root->id.bus)) {
231			int bus = 0;
232			acpi_status status;
233
234			printk(KERN_ERR PREFIX
235				    "Wrong _BBN value, reboot"
236				    " and use option 'pci=noacpi'\n");
237
238			status = try_get_root_bridge_busnr(device->handle, &bus);
239			if (ACPI_FAILURE(status))
240				break;
241			if (bus != root->id.bus) {
242				printk(KERN_INFO PREFIX
243				       "PCI _CRS %d overrides _BBN 0\n", bus);
244				root->id.bus = bus;
245			}
246			break;
247		}
248	}
249	/*
250	 * Device & Function
251	 * -----------------
252	 * Obtained from _ADR (which has already been evaluated for us).
253	 */
254	root->id.device = device->pnp.bus_address >> 16;
255	root->id.function = device->pnp.bus_address & 0xFFFF;
256
257	/*
258	 * TBD: Need PCI interface for enumeration/configuration of roots.
259	 */
260
261	/* TBD: Locking */
262	list_add_tail(&root->node, &acpi_pci_roots);
263
264	printk(KERN_INFO PREFIX "%s [%s] (%04x:%02x)\n",
265	       acpi_device_name(device), acpi_device_bid(device),
266	       root->id.segment, root->id.bus);
267
268	/*
269	 * Scan the Root Bridge
270	 * --------------------
271	 * Must do this prior to any attempt to bind the root device, as the
272	 * PCI namespace does not get created until this call is made (and
273	 * thus the root bridge's pci_dev does not exist).
274	 */
275	root->bus = pci_acpi_scan_root(device, root->id.segment, root->id.bus);
276	if (!root->bus) {
277		printk(KERN_ERR PREFIX
278			    "Bus %04x:%02x not present in PCI namespace\n",
279			    root->id.segment, root->id.bus);
280		result = -ENODEV;
281		goto end;
282	}
283
284	/*
285	 * Attach ACPI-PCI Context
286	 * -----------------------
287	 * Thus binding the ACPI and PCI devices.
288	 */
289	result = acpi_pci_bind_root(device, &root->id, root->bus);
290	if (result)
291		goto end;
292
293	/*
294	 * PCI Routing Table
295	 * -----------------
296	 * Evaluate and parse _PRT, if exists.
297	 */
298	status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
299	if (ACPI_SUCCESS(status))
300		result = acpi_pci_irq_add_prt(device->handle, root->id.segment,
301					      root->id.bus);
302
303      end:
304	if (result) {
305		if (!list_empty(&root->node))
306			list_del(&root->node);
307		kfree(root);
308	}
309
310	return result;
311}
312
313static int acpi_pci_root_start(struct acpi_device *device)
314{
315	struct acpi_pci_root *root;
316
317
318	list_for_each_entry(root, &acpi_pci_roots, node) {
319		if (root->device == device) {
320			pci_bus_add_devices(root->bus);
321			return 0;
322		}
323	}
324	return -ENODEV;
325}
326
327static int acpi_pci_root_remove(struct acpi_device *device, int type)
328{
329	struct acpi_pci_root *root = NULL;
330
331
332	if (!device || !acpi_driver_data(device))
333		return -EINVAL;
334
335	root = (struct acpi_pci_root *)acpi_driver_data(device);
336
337	kfree(root);
338
339	return 0;
340}
341
342static int __init acpi_pci_root_init(void)
343{
344
345	if (acpi_pci_disabled)
346		return 0;
347
348	/* DEBUG:
349	   acpi_dbg_layer = ACPI_PCI_COMPONENT;
350	   acpi_dbg_level = 0xFFFFFFFF;
351	 */
352
353	if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
354		return -ENODEV;
355
356	return 0;
357}
358
359subsys_initcall(acpi_pci_root_init);
360