1 /*
2  *  pci_root.c - ACPI PCI Root Bridge Driver ($Revision: 41 $)
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 
39 #define _COMPONENT		ACPI_PCI_COMPONENT
40 ACPI_MODULE_NAME		("pci_root")
41 
42 extern struct pci_ops *pci_root_ops;
43 
44 #define PREFIX			"ACPI: "
45 
46 static int acpi_pci_root_add (struct acpi_device *device);
47 static int acpi_pci_root_remove (struct acpi_device *device, int type);
48 
49 static struct acpi_driver acpi_pci_root_driver = {
50 	.name =		ACPI_PCI_ROOT_DRIVER_NAME,
51 	.class =	ACPI_PCI_ROOT_CLASS,
52 	.ids =		ACPI_PCI_ROOT_HID,
53 	.ops =		{
54 				.add =    acpi_pci_root_add,
55 				.remove = acpi_pci_root_remove,
56 			},
57 };
58 
59 struct acpi_pci_root {
60 	struct list_head	node;
61 	acpi_handle		handle;
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 
acpi_pci_register_driver(struct acpi_pci_driver * driver)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->handle);
87 		n++;
88 	}
89 
90 	return n;
91 }
92 
acpi_pci_unregister_driver(struct acpi_pci_driver * driver)93 void acpi_pci_unregister_driver(struct acpi_pci_driver *driver)
94 {
95 	struct list_head *entry;
96 
97 	struct acpi_pci_driver **pptr = &sub_driver;
98 	while (*pptr) {
99 		if (*pptr != driver)
100 			continue;
101 		*pptr = (*pptr)->next;
102 		break;
103 	}
104 
105 	if (!driver->remove)
106 		return;
107 
108 	list_for_each(entry, &acpi_pci_roots) {
109 		struct acpi_pci_root *root;
110 		root = list_entry(entry, struct acpi_pci_root, node);
111 		driver->remove(root->handle);
112 	}
113 }
114 
115 static acpi_status
get_root_bridge_busnr_callback(struct acpi_resource * resource,void * data)116 get_root_bridge_busnr_callback (struct acpi_resource *resource, void *data)
117 {
118 	int *busnr = (int *)data;
119 	struct acpi_resource_address64 address;
120 
121 	if (resource->id != ACPI_RSTYPE_ADDRESS16 &&
122 	    resource->id != ACPI_RSTYPE_ADDRESS32 &&
123 	    resource->id != ACPI_RSTYPE_ADDRESS64)
124 		return AE_OK;
125 
126 	acpi_resource_to_address64(resource, &address);
127 	if ((address.address_length > 0) &&
128 	   (address.resource_type == ACPI_BUS_NUMBER_RANGE))
129 		*busnr = address.min_address_range;
130 
131 	return AE_OK;
132 }
133 
134 static acpi_status
try_get_root_bridge_busnr(acpi_handle handle,int * busnum)135 try_get_root_bridge_busnr(acpi_handle handle, int *busnum)
136 {
137 	acpi_status status;
138 
139 	*busnum = -1;
140 	status = acpi_walk_resources(handle, METHOD_NAME__CRS, get_root_bridge_busnr_callback, busnum);
141 	if (ACPI_FAILURE(status))
142 		return status;
143 	/* Check if we really get a bus number from _CRS */
144 	if (*busnum == -1)
145 		return AE_ERROR;
146 	return AE_OK;
147 }
148 
149 static int
acpi_pci_root_add(struct acpi_device * device)150 acpi_pci_root_add (
151 	struct acpi_device	*device)
152 {
153 	int			result = 0;
154 	struct acpi_pci_root	*root = NULL;
155 	struct acpi_pci_root	*tmp;
156 	acpi_status		status = AE_OK;
157 	unsigned long		value = 0;
158 	acpi_handle		handle = NULL;
159 
160 	ACPI_FUNCTION_TRACE("acpi_pci_root_add");
161 
162 	if (!device)
163 		return_VALUE(-EINVAL);
164 
165 	root = kmalloc(sizeof(struct acpi_pci_root), GFP_KERNEL);
166 	if (!root)
167 		return_VALUE(-ENOMEM);
168 	memset(root, 0, sizeof(struct acpi_pci_root));
169 
170 	root->handle = device->handle;
171 	sprintf(acpi_device_name(device), "%s", ACPI_PCI_ROOT_DEVICE_NAME);
172 	sprintf(acpi_device_class(device), "%s", ACPI_PCI_ROOT_CLASS);
173 	acpi_driver_data(device) = root;
174 
175 	/*
176 	 * TBD: Doesn't the bus driver automatically set this?
177 	 */
178 	device->ops.bind = acpi_pci_bind;
179 
180 	/*
181 	 * Segment
182 	 * -------
183 	 * Obtained via _SEG, if exists, otherwise assumed to be zero (0).
184 	 */
185 	status = acpi_evaluate_integer(root->handle, METHOD_NAME__SEG, NULL,
186 		&value);
187 	switch (status) {
188 	case AE_OK:
189 		root->id.segment = (u16) value;
190 		break;
191 	case AE_NOT_FOUND:
192 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
193 			"Assuming segment 0 (no _SEG)\n"));
194 		root->id.segment = 0;
195 		break;
196 	default:
197 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _SEG\n"));
198 		result = -ENODEV;
199 		goto end;
200 	}
201 
202 	/*
203 	 * Bus
204 	 * ---
205 	 * Obtained via _BBN, if exists, otherwise assumed to be zero (0).
206 	 */
207 	status = acpi_evaluate_integer(root->handle, METHOD_NAME__BBN, NULL,
208 		&value);
209 	switch (status) {
210 	case AE_OK:
211 		root->id.bus = (u16) value;
212 		break;
213 	case AE_NOT_FOUND:
214 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Assuming bus 0 (no _BBN)\n"));
215 		root->id.bus = 0;
216 		break;
217 	default:
218 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _BBN\n"));
219 		result = -ENODEV;
220 		goto end;
221 	}
222 
223 	/* Some systems have wrong _BBN */
224 	list_for_each_entry(tmp, &acpi_pci_roots, node) {
225 		if ((tmp->id.segment == root->id.segment)
226 				&& (tmp->id.bus == root->id.bus)) {
227 			int bus = 0;
228 			acpi_status status;
229 
230 			ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
231 				"Wrong _BBN value, please reboot and using option 'pci=noacpi'\n"));
232 
233 			status = try_get_root_bridge_busnr(root->handle, &bus);
234 			if (ACPI_FAILURE(status))
235 				break;
236 			if (bus != root->id.bus) {
237 				printk(KERN_INFO PREFIX "PCI _CRS %d overrides _BBN 0\n", bus);
238 				root->id.bus = bus;
239 			}
240 			break;
241 		}
242 	}
243 
244 	/*
245 	 * Device & Function
246 	 * -----------------
247 	 * Obtained from _ADR (which has already been evaluated for us).
248 	 */
249 	root->id.device = device->pnp.bus_address >> 16;
250 	root->id.function = device->pnp.bus_address & 0xFFFF;
251 
252 	/*
253 	 * TBD: Need PCI interface for enumeration/configuration of roots.
254 	 */
255 
256  	/* TBD: Locking */
257  	list_add_tail(&root->node, &acpi_pci_roots);
258 
259 	printk(KERN_INFO PREFIX "%s [%s] (%02x:%02x)\n",
260 		acpi_device_name(device), acpi_device_bid(device),
261 		root->id.segment, root->id.bus);
262 
263 	/*
264 	 * Scan the Root Bridge
265 	 * --------------------
266 	 * Must do this prior to any attempt to bind the root device, as the
267 	 * PCI namespace does not get created until this call is made (and
268 	 * thus the root bridge's pci_dev does not exist).
269 	 */
270 #ifdef CONFIG_X86
271 	root->bus = pcibios_scan_root(root->id.bus);
272 #else
273 	root->bus = pcibios_scan_root(root->handle,
274 				      root->id.segment, root->id.bus);
275 #endif
276 	if (!root->bus) {
277 		ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
278 			"Bus %02x:%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(root->handle, METHOD_NAME__PRT, &handle);
299 	if (ACPI_SUCCESS(status))
300 		result = acpi_pci_irq_add_prt(root->handle, root->id.segment,
301 			root->id.bus);
302 
303 end:
304 	if (result)
305 		kfree(root);
306 
307 	return_VALUE(result);
308 }
309 
310 
311 static int
acpi_pci_root_remove(struct acpi_device * device,int type)312 acpi_pci_root_remove (
313 	struct acpi_device	*device,
314 	int			type)
315 {
316 	struct acpi_pci_root	*root = NULL;
317 
318 	ACPI_FUNCTION_TRACE("acpi_pci_root_remove");
319 
320 	if (!device || !acpi_driver_data(device))
321 		return_VALUE(-EINVAL);
322 
323 	root = (struct acpi_pci_root *) acpi_driver_data(device);
324 
325 	kfree(root);
326 
327 	return_VALUE(0);
328 }
329 
330 
331 int __init
acpi_pci_root_init(void)332 acpi_pci_root_init (void)
333 {
334 	ACPI_FUNCTION_TRACE("acpi_pci_root_init");
335 
336 	/* DEBUG:
337 	acpi_dbg_layer = ACPI_PCI_COMPONENT;
338 	acpi_dbg_level = 0xFFFFFFFF;
339 	 */
340 
341 	if (acpi_bus_register_driver(&acpi_pci_root_driver) < 0)
342 		return_VALUE(-ENODEV);
343 
344 	return_VALUE(0);
345 }
346 
347 
348 void __exit
acpi_pci_root_exit(void)349 acpi_pci_root_exit (void)
350 {
351 	ACPI_FUNCTION_TRACE("acpi_pci_root_exit");
352 
353 	acpi_bus_unregister_driver(&acpi_pci_root_driver);
354 
355 	return_VOID;
356 }
357