xref: /linux/drivers/acpi/pci_root.c (revision 14b42963f64b98ab61fa9723c03d71aa5ef4f862)
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
39 ACPI_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"
44 static int acpi_pci_root_add(struct acpi_device *device);
45 static int acpi_pci_root_remove(struct acpi_device *device, int type);
46 static int acpi_pci_root_start(struct acpi_device *device);
47 
48 static 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 
59 struct 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 
66 static LIST_HEAD(acpi_pci_roots);
67 
68 static struct acpi_pci_driver *sub_driver;
69 
70 int 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 
93 EXPORT_SYMBOL(acpi_pci_register_driver);
94 
95 void 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 			continue;
103 		*pptr = (*pptr)->next;
104 		break;
105 	}
106 
107 	if (!driver->remove)
108 		return;
109 
110 	list_for_each(entry, &acpi_pci_roots) {
111 		struct acpi_pci_root *root;
112 		root = list_entry(entry, struct acpi_pci_root, node);
113 		driver->remove(root->device->handle);
114 	}
115 }
116 
117 EXPORT_SYMBOL(acpi_pci_unregister_driver);
118 
119 static acpi_status
120 get_root_bridge_busnr_callback(struct acpi_resource *resource, void *data)
121 {
122 	int *busnr = (int *)data;
123 	struct acpi_resource_address64 address;
124 
125 	if (resource->type != ACPI_RESOURCE_TYPE_ADDRESS16 &&
126 	    resource->type != ACPI_RESOURCE_TYPE_ADDRESS32 &&
127 	    resource->type != ACPI_RESOURCE_TYPE_ADDRESS64)
128 		return AE_OK;
129 
130 	acpi_resource_to_address64(resource, &address);
131 	if ((address.address_length > 0) &&
132 	    (address.resource_type == ACPI_BUS_NUMBER_RANGE))
133 		*busnr = address.minimum;
134 
135 	return AE_OK;
136 }
137 
138 static acpi_status try_get_root_bridge_busnr(acpi_handle handle, int *busnum)
139 {
140 	acpi_status status;
141 
142 	*busnum = -1;
143 	status =
144 	    acpi_walk_resources(handle, METHOD_NAME__CRS,
145 				get_root_bridge_busnr_callback, busnum);
146 	if (ACPI_FAILURE(status))
147 		return status;
148 	/* Check if we really get a bus number from _CRS */
149 	if (*busnum == -1)
150 		return AE_ERROR;
151 	return AE_OK;
152 }
153 
154 static int acpi_pci_root_add(struct acpi_device *device)
155 {
156 	int result = 0;
157 	struct acpi_pci_root *root = NULL;
158 	struct acpi_pci_root *tmp;
159 	acpi_status status = AE_OK;
160 	unsigned long value = 0;
161 	acpi_handle handle = NULL;
162 
163 
164 	if (!device)
165 		return -EINVAL;
166 
167 	root = kmalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
168 	if (!root)
169 		return -ENOMEM;
170 	memset(root, 0, sizeof(struct acpi_pci_root));
171 	INIT_LIST_HEAD(&root->node);
172 
173 	root->device = device;
174 	strcpy(acpi_device_name(device), ACPI_PCI_ROOT_DEVICE_NAME);
175 	strcpy(acpi_device_class(device), ACPI_PCI_ROOT_CLASS);
176 	acpi_driver_data(device) = root;
177 
178 	/*
179 	 * TBD: Doesn't the bus driver automatically set this?
180 	 */
181 	device->ops.bind = acpi_pci_bind;
182 
183 	/*
184 	 * Segment
185 	 * -------
186 	 * Obtained via _SEG, if exists, otherwise assumed to be zero (0).
187 	 */
188 	status = acpi_evaluate_integer(device->handle, METHOD_NAME__SEG, NULL,
189 				       &value);
190 	switch (status) {
191 	case AE_OK:
192 		root->id.segment = (u16) value;
193 		break;
194 	case AE_NOT_FOUND:
195 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
196 				  "Assuming segment 0 (no _SEG)\n"));
197 		root->id.segment = 0;
198 		break;
199 	default:
200 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _SEG"));
201 		result = -ENODEV;
202 		goto end;
203 	}
204 
205 	/*
206 	 * Bus
207 	 * ---
208 	 * Obtained via _BBN, if exists, otherwise assumed to be zero (0).
209 	 */
210 	status = acpi_evaluate_integer(device->handle, METHOD_NAME__BBN, NULL,
211 				       &value);
212 	switch (status) {
213 	case AE_OK:
214 		root->id.bus = (u16) value;
215 		break;
216 	case AE_NOT_FOUND:
217 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Assuming bus 0 (no _BBN)\n"));
218 		root->id.bus = 0;
219 		break;
220 	default:
221 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _BBN"));
222 		result = -ENODEV;
223 		goto end;
224 	}
225 
226 	/* Some systems have wrong _BBN */
227 	list_for_each_entry(tmp, &acpi_pci_roots, node) {
228 		if ((tmp->id.segment == root->id.segment)
229 		    && (tmp->id.bus == root->id.bus)) {
230 			int bus = 0;
231 			acpi_status status;
232 
233 			printk(KERN_ERR PREFIX
234 				    "Wrong _BBN value, reboot"
235 				    " and use option 'pci=noacpi'\n");
236 
237 			status = try_get_root_bridge_busnr(device->handle, &bus);
238 			if (ACPI_FAILURE(status))
239 				break;
240 			if (bus != root->id.bus) {
241 				printk(KERN_INFO PREFIX
242 				       "PCI _CRS %d overrides _BBN 0\n", bus);
243 				root->id.bus = bus;
244 			}
245 			break;
246 		}
247 	}
248 	/*
249 	 * Device & Function
250 	 * -----------------
251 	 * Obtained from _ADR (which has already been evaluated for us).
252 	 */
253 	root->id.device = device->pnp.bus_address >> 16;
254 	root->id.function = device->pnp.bus_address & 0xFFFF;
255 
256 	/*
257 	 * TBD: Need PCI interface for enumeration/configuration of roots.
258 	 */
259 
260 	/* TBD: Locking */
261 	list_add_tail(&root->node, &acpi_pci_roots);
262 
263 	printk(KERN_INFO PREFIX "%s [%s] (%04x:%02x)\n",
264 	       acpi_device_name(device), acpi_device_bid(device),
265 	       root->id.segment, root->id.bus);
266 
267 	/*
268 	 * Scan the Root Bridge
269 	 * --------------------
270 	 * Must do this prior to any attempt to bind the root device, as the
271 	 * PCI namespace does not get created until this call is made (and
272 	 * thus the root bridge's pci_dev does not exist).
273 	 */
274 	root->bus = pci_acpi_scan_root(device, root->id.segment, root->id.bus);
275 	if (!root->bus) {
276 		printk(KERN_ERR PREFIX
277 			    "Bus %04x:%02x not present in PCI namespace\n",
278 			    root->id.segment, root->id.bus);
279 		result = -ENODEV;
280 		goto end;
281 	}
282 
283 	/*
284 	 * Attach ACPI-PCI Context
285 	 * -----------------------
286 	 * Thus binding the ACPI and PCI devices.
287 	 */
288 	result = acpi_pci_bind_root(device, &root->id, root->bus);
289 	if (result)
290 		goto end;
291 
292 	/*
293 	 * PCI Routing Table
294 	 * -----------------
295 	 * Evaluate and parse _PRT, if exists.
296 	 */
297 	status = acpi_get_handle(device->handle, METHOD_NAME__PRT, &handle);
298 	if (ACPI_SUCCESS(status))
299 		result = acpi_pci_irq_add_prt(device->handle, root->id.segment,
300 					      root->id.bus);
301 
302       end:
303 	if (result) {
304 		if (!list_empty(&root->node))
305 			list_del(&root->node);
306 		kfree(root);
307 	}
308 
309 	return result;
310 }
311 
312 static int acpi_pci_root_start(struct acpi_device *device)
313 {
314 	struct acpi_pci_root *root;
315 
316 
317 	list_for_each_entry(root, &acpi_pci_roots, node) {
318 		if (root->device == device) {
319 			pci_bus_add_devices(root->bus);
320 			return 0;
321 		}
322 	}
323 	return -ENODEV;
324 }
325 
326 static int acpi_pci_root_remove(struct acpi_device *device, int type)
327 {
328 	struct acpi_pci_root *root = NULL;
329 
330 
331 	if (!device || !acpi_driver_data(device))
332 		return -EINVAL;
333 
334 	root = (struct acpi_pci_root *)acpi_driver_data(device);
335 
336 	kfree(root);
337 
338 	return 0;
339 }
340 
341 static int __init acpi_pci_root_init(void)
342 {
343 
344 	if (acpi_pci_disabled)
345 		return 0;
346 
347 	/* DEBUG:
348 	   acpi_dbg_layer = ACPI_PCI_COMPONENT;
349 	   acpi_dbg_level = 0xFFFFFFFF;
350 	 */
351 
352 	if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
353 		return -ENODEV;
354 
355 	return 0;
356 }
357 
358 subsys_initcall(acpi_pci_root_init);
359