Merge branch 'upstream-fixes'
[linux-2.6] / drivers / acpi / pci_irq.c
1 /*
2  *  pci_irq.c - ACPI PCI Interrupt Routing ($Revision: 11 $)
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  *  Copyright (C) 2002       Dominik Brodowski <devel@brodo.de>
7  *
8  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
9  *
10  *  This program is free software; you can redistribute it and/or modify
11  *  it under the terms of the GNU General Public License as published by
12  *  the Free Software Foundation; either version 2 of the License, or (at
13  *  your option) any later version.
14  *
15  *  This program is distributed in the hope that it will be useful, but
16  *  WITHOUT ANY WARRANTY; without even the implied warranty of
17  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18  *  General Public License for more details.
19  *
20  *  You should have received a copy of the GNU General Public License along
21  *  with this program; if not, write to the Free Software Foundation, Inc.,
22  *  59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
23  *
24  * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
25  */
26
27 #include <linux/config.h>
28
29 #include <linux/kernel.h>
30 #include <linux/module.h>
31 #include <linux/init.h>
32 #include <linux/types.h>
33 #include <linux/proc_fs.h>
34 #include <linux/spinlock.h>
35 #include <linux/pm.h>
36 #include <linux/pci.h>
37 #include <linux/acpi.h>
38 #include <acpi/acpi_bus.h>
39 #include <acpi/acpi_drivers.h>
40
41 #define _COMPONENT              ACPI_PCI_COMPONENT
42 ACPI_MODULE_NAME("pci_irq")
43
44 static struct acpi_prt_list acpi_prt;
45 static DEFINE_SPINLOCK(acpi_prt_lock);
46
47 /* --------------------------------------------------------------------------
48                          PCI IRQ Routing Table (PRT) Support
49    -------------------------------------------------------------------------- */
50
51 static struct acpi_prt_entry *acpi_pci_irq_find_prt_entry(int segment,
52                                                           int bus,
53                                                           int device, int pin)
54 {
55         struct list_head *node = NULL;
56         struct acpi_prt_entry *entry = NULL;
57
58         ACPI_FUNCTION_TRACE("acpi_pci_irq_find_prt_entry");
59
60         if (!acpi_prt.count)
61                 return_PTR(NULL);
62
63         /*
64          * Parse through all PRT entries looking for a match on the specified
65          * PCI device's segment, bus, device, and pin (don't care about func).
66          *
67          */
68         spin_lock(&acpi_prt_lock);
69         list_for_each(node, &acpi_prt.entries) {
70                 entry = list_entry(node, struct acpi_prt_entry, node);
71                 if ((segment == entry->id.segment)
72                     && (bus == entry->id.bus)
73                     && (device == entry->id.device)
74                     && (pin == entry->pin)) {
75                         spin_unlock(&acpi_prt_lock);
76                         return_PTR(entry);
77                 }
78         }
79
80         spin_unlock(&acpi_prt_lock);
81         return_PTR(NULL);
82 }
83
84 static int
85 acpi_pci_irq_add_entry(acpi_handle handle,
86                        int segment, int bus, struct acpi_pci_routing_table *prt)
87 {
88         struct acpi_prt_entry *entry = NULL;
89
90         ACPI_FUNCTION_TRACE("acpi_pci_irq_add_entry");
91
92         if (!prt)
93                 return_VALUE(-EINVAL);
94
95         entry = kmalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL);
96         if (!entry)
97                 return_VALUE(-ENOMEM);
98         memset(entry, 0, sizeof(struct acpi_prt_entry));
99
100         entry->id.segment = segment;
101         entry->id.bus = bus;
102         entry->id.device = (prt->address >> 16) & 0xFFFF;
103         entry->id.function = prt->address & 0xFFFF;
104         entry->pin = prt->pin;
105
106         /*
107          * Type 1: Dynamic
108          * ---------------
109          * The 'source' field specifies the PCI interrupt link device used to
110          * configure the IRQ assigned to this slot|dev|pin.  The 'source_index'
111          * indicates which resource descriptor in the resource template (of
112          * the link device) this interrupt is allocated from.
113          * 
114          * NOTE: Don't query the Link Device for IRQ information at this time
115          *       because Link Device enumeration may not have occurred yet
116          *       (e.g. exists somewhere 'below' this _PRT entry in the ACPI
117          *       namespace).
118          */
119         if (prt->source[0]) {
120                 acpi_get_handle(handle, prt->source, &entry->link.handle);
121                 entry->link.index = prt->source_index;
122         }
123         /*
124          * Type 2: Static
125          * --------------
126          * The 'source' field is NULL, and the 'source_index' field specifies
127          * the IRQ value, which is hardwired to specific interrupt inputs on
128          * the interrupt controller.
129          */
130         else
131                 entry->link.index = prt->source_index;
132
133         ACPI_DEBUG_PRINT_RAW((ACPI_DB_INFO,
134                               "      %02X:%02X:%02X[%c] -> %s[%d]\n",
135                               entry->id.segment, entry->id.bus,
136                               entry->id.device, ('A' + entry->pin), prt->source,
137                               entry->link.index));
138
139         spin_lock(&acpi_prt_lock);
140         list_add_tail(&entry->node, &acpi_prt.entries);
141         acpi_prt.count++;
142         spin_unlock(&acpi_prt_lock);
143
144         return_VALUE(0);
145 }
146
147 static void
148 acpi_pci_irq_del_entry(int segment, int bus, struct acpi_prt_entry *entry)
149 {
150         if (segment == entry->id.segment && bus == entry->id.bus) {
151                 acpi_prt.count--;
152                 list_del(&entry->node);
153                 kfree(entry);
154         }
155 }
156
157 int acpi_pci_irq_add_prt(acpi_handle handle, int segment, int bus)
158 {
159         acpi_status status = AE_OK;
160         char *pathname = NULL;
161         struct acpi_buffer buffer = { 0, NULL };
162         struct acpi_pci_routing_table *prt = NULL;
163         struct acpi_pci_routing_table *entry = NULL;
164         static int first_time = 1;
165
166         ACPI_FUNCTION_TRACE("acpi_pci_irq_add_prt");
167
168         pathname = (char *)kmalloc(ACPI_PATHNAME_MAX, GFP_KERNEL);
169         if (!pathname)
170                 return_VALUE(-ENOMEM);
171         memset(pathname, 0, ACPI_PATHNAME_MAX);
172
173         if (first_time) {
174                 acpi_prt.count = 0;
175                 INIT_LIST_HEAD(&acpi_prt.entries);
176                 first_time = 0;
177         }
178
179         /* 
180          * NOTE: We're given a 'handle' to the _PRT object's parent device
181          *       (either a PCI root bridge or PCI-PCI bridge).
182          */
183
184         buffer.length = ACPI_PATHNAME_MAX;
185         buffer.pointer = pathname;
186         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
187
188         printk(KERN_DEBUG "ACPI: PCI Interrupt Routing Table [%s._PRT]\n",
189                pathname);
190
191         /* 
192          * Evaluate this _PRT and add its entries to our global list (acpi_prt).
193          */
194
195         buffer.length = 0;
196         buffer.pointer = NULL;
197         kfree(pathname);
198         status = acpi_get_irq_routing_table(handle, &buffer);
199         if (status != AE_BUFFER_OVERFLOW) {
200                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PRT [%s]\n",
201                                   acpi_format_exception(status)));
202                 return_VALUE(-ENODEV);
203         }
204
205         prt = kmalloc(buffer.length, GFP_KERNEL);
206         if (!prt) {
207                 return_VALUE(-ENOMEM);
208         }
209         memset(prt, 0, buffer.length);
210         buffer.pointer = prt;
211
212         status = acpi_get_irq_routing_table(handle, &buffer);
213         if (ACPI_FAILURE(status)) {
214                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PRT [%s]\n",
215                                   acpi_format_exception(status)));
216                 kfree(buffer.pointer);
217                 return_VALUE(-ENODEV);
218         }
219
220         entry = prt;
221
222         while (entry && (entry->length > 0)) {
223                 acpi_pci_irq_add_entry(handle, segment, bus, entry);
224                 entry = (struct acpi_pci_routing_table *)
225                     ((unsigned long)entry + entry->length);
226         }
227
228         kfree(prt);
229
230         return_VALUE(0);
231 }
232
233 void acpi_pci_irq_del_prt(int segment, int bus)
234 {
235         struct list_head *node = NULL, *n = NULL;
236         struct acpi_prt_entry *entry = NULL;
237
238         if (!acpi_prt.count) {
239                 return;
240         }
241
242         printk(KERN_DEBUG
243                "ACPI: Delete PCI Interrupt Routing Table for %x:%x\n", segment,
244                bus);
245         spin_lock(&acpi_prt_lock);
246         list_for_each_safe(node, n, &acpi_prt.entries) {
247                 entry = list_entry(node, struct acpi_prt_entry, node);
248
249                 acpi_pci_irq_del_entry(segment, bus, entry);
250         }
251         spin_unlock(&acpi_prt_lock);
252 }
253
254 /* --------------------------------------------------------------------------
255                           PCI Interrupt Routing Support
256    -------------------------------------------------------------------------- */
257 typedef int (*irq_lookup_func) (struct acpi_prt_entry *, int *, int *, char **);
258
259 static int
260 acpi_pci_allocate_irq(struct acpi_prt_entry *entry,
261                       int *edge_level, int *active_high_low, char **link)
262 {
263         int irq;
264
265         ACPI_FUNCTION_TRACE("acpi_pci_allocate_irq");
266
267         if (entry->link.handle) {
268                 irq = acpi_pci_link_allocate_irq(entry->link.handle,
269                                                  entry->link.index, edge_level,
270                                                  active_high_low, link);
271                 if (irq < 0) {
272                         ACPI_DEBUG_PRINT((ACPI_DB_WARN,
273                                           "Invalid IRQ link routing entry\n"));
274                         return_VALUE(-1);
275                 }
276         } else {
277                 irq = entry->link.index;
278                 *edge_level = ACPI_LEVEL_SENSITIVE;
279                 *active_high_low = ACPI_ACTIVE_LOW;
280         }
281
282         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found IRQ %d\n", irq));
283         return_VALUE(irq);
284 }
285
286 static int
287 acpi_pci_free_irq(struct acpi_prt_entry *entry,
288                   int *edge_level, int *active_high_low, char **link)
289 {
290         int irq;
291
292         ACPI_FUNCTION_TRACE("acpi_pci_free_irq");
293         if (entry->link.handle) {
294                 irq = acpi_pci_link_free_irq(entry->link.handle);
295         } else {
296                 irq = entry->link.index;
297         }
298         return_VALUE(irq);
299 }
300
301 /*
302  * acpi_pci_irq_lookup
303  * success: return IRQ >= 0
304  * failure: return -1
305  */
306 static int
307 acpi_pci_irq_lookup(struct pci_bus *bus,
308                     int device,
309                     int pin,
310                     int *edge_level,
311                     int *active_high_low, char **link, irq_lookup_func func)
312 {
313         struct acpi_prt_entry *entry = NULL;
314         int segment = pci_domain_nr(bus);
315         int bus_nr = bus->number;
316         int ret;
317
318         ACPI_FUNCTION_TRACE("acpi_pci_irq_lookup");
319
320         ACPI_DEBUG_PRINT((ACPI_DB_INFO,
321                           "Searching for PRT entry for %02x:%02x:%02x[%c]\n",
322                           segment, bus_nr, device, ('A' + pin)));
323
324         entry = acpi_pci_irq_find_prt_entry(segment, bus_nr, device, pin);
325         if (!entry) {
326                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PRT entry not found\n"));
327                 return_VALUE(-1);
328         }
329
330         ret = func(entry, edge_level, active_high_low, link);
331         return_VALUE(ret);
332 }
333
334 /*
335  * acpi_pci_irq_derive
336  * success: return IRQ >= 0
337  * failure: return < 0
338  */
339 static int
340 acpi_pci_irq_derive(struct pci_dev *dev,
341                     int pin,
342                     int *edge_level,
343                     int *active_high_low, char **link, irq_lookup_func func)
344 {
345         struct pci_dev *bridge = dev;
346         int irq = -1;
347         u8 bridge_pin = 0;
348
349         ACPI_FUNCTION_TRACE("acpi_pci_irq_derive");
350
351         if (!dev)
352                 return_VALUE(-EINVAL);
353
354         /* 
355          * Attempt to derive an IRQ for this device from a parent bridge's
356          * PCI interrupt routing entry (eg. yenta bridge and add-in card bridge).
357          */
358         while (irq < 0 && bridge->bus->self) {
359                 pin = (pin + PCI_SLOT(bridge->devfn)) % 4;
360                 bridge = bridge->bus->self;
361
362                 if ((bridge->class >> 8) == PCI_CLASS_BRIDGE_CARDBUS) {
363                         /* PC card has the same IRQ as its cardbridge */
364                         pci_read_config_byte(bridge, PCI_INTERRUPT_PIN,
365                                              &bridge_pin);
366                         if (!bridge_pin) {
367                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
368                                                   "No interrupt pin configured for device %s\n",
369                                                   pci_name(bridge)));
370                                 return_VALUE(-1);
371                         }
372                         /* Pin is from 0 to 3 */
373                         bridge_pin--;
374                         pin = bridge_pin;
375                 }
376
377                 irq = acpi_pci_irq_lookup(bridge->bus, PCI_SLOT(bridge->devfn),
378                                           pin, edge_level, active_high_low,
379                                           link, func);
380         }
381
382         if (irq < 0) {
383                 ACPI_DEBUG_PRINT((ACPI_DB_WARN,
384                                   "Unable to derive IRQ for device %s\n",
385                                   pci_name(dev)));
386                 return_VALUE(-1);
387         }
388
389         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Derive IRQ %d for device %s from %s\n",
390                           irq, pci_name(dev), pci_name(bridge)));
391
392         return_VALUE(irq);
393 }
394
395 /*
396  * acpi_pci_irq_enable
397  * success: return 0
398  * failure: return < 0
399  */
400
401 int acpi_pci_irq_enable(struct pci_dev *dev)
402 {
403         int irq = 0;
404         u8 pin = 0;
405         int edge_level = ACPI_LEVEL_SENSITIVE;
406         int active_high_low = ACPI_ACTIVE_LOW;
407         char *link = NULL;
408         int rc;
409
410         ACPI_FUNCTION_TRACE("acpi_pci_irq_enable");
411
412         if (!dev)
413                 return_VALUE(-EINVAL);
414
415         pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
416         if (!pin) {
417                 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
418                                   "No interrupt pin configured for device %s\n",
419                                   pci_name(dev)));
420                 return_VALUE(0);
421         }
422         pin--;
423
424         if (!dev->bus) {
425                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR,
426                                   "Invalid (NULL) 'bus' field\n"));
427                 return_VALUE(-ENODEV);
428         }
429
430         /* 
431          * First we check the PCI IRQ routing table (PRT) for an IRQ.  PRT
432          * values override any BIOS-assigned IRQs set during boot.
433          */
434         irq = acpi_pci_irq_lookup(dev->bus, PCI_SLOT(dev->devfn), pin,
435                                   &edge_level, &active_high_low, &link,
436                                   acpi_pci_allocate_irq);
437
438         /*
439          * If no PRT entry was found, we'll try to derive an IRQ from the
440          * device's parent bridge.
441          */
442         if (irq < 0)
443                 irq = acpi_pci_irq_derive(dev, pin, &edge_level,
444                                           &active_high_low, &link,
445                                           acpi_pci_allocate_irq);
446
447         /*
448          * No IRQ known to the ACPI subsystem - maybe the BIOS / 
449          * driver reported one, then use it. Exit in any case.
450          */
451         if (irq < 0) {
452                 printk(KERN_WARNING PREFIX "PCI Interrupt %s[%c]: no GSI",
453                        pci_name(dev), ('A' + pin));
454                 /* Interrupt Line values above 0xF are forbidden */
455                 if (dev->irq > 0 && (dev->irq <= 0xF)) {
456                         printk(" - using IRQ %d\n", dev->irq);
457                         acpi_register_gsi(dev->irq, ACPI_LEVEL_SENSITIVE,
458                                           ACPI_ACTIVE_LOW);
459                         return_VALUE(0);
460                 } else {
461                         printk("\n");
462                         return_VALUE(0);
463                 }
464         }
465
466         rc = acpi_register_gsi(irq, edge_level, active_high_low);
467         if (rc < 0) {
468                 printk(KERN_WARNING PREFIX "PCI Interrupt %s[%c]: failed "
469                        "to register GSI\n", pci_name(dev), ('A' + pin));
470                 return_VALUE(rc);
471         }
472         dev->irq = rc;
473
474         printk(KERN_INFO PREFIX "PCI Interrupt %s[%c] -> ",
475                pci_name(dev), 'A' + pin);
476
477         if (link)
478                 printk("Link [%s] -> ", link);
479
480         printk("GSI %u (%s, %s) -> IRQ %d\n", irq,
481                (edge_level == ACPI_LEVEL_SENSITIVE) ? "level" : "edge",
482                (active_high_low == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq);
483
484         return_VALUE(0);
485 }
486
487 EXPORT_SYMBOL(acpi_pci_irq_enable);
488
489 /* FIXME: implement x86/x86_64 version */
490 void __attribute__ ((weak)) acpi_unregister_gsi(u32 i)
491 {
492 }
493
494 void acpi_pci_irq_disable(struct pci_dev *dev)
495 {
496         int gsi = 0;
497         u8 pin = 0;
498         int edge_level = ACPI_LEVEL_SENSITIVE;
499         int active_high_low = ACPI_ACTIVE_LOW;
500
501         ACPI_FUNCTION_TRACE("acpi_pci_irq_disable");
502
503         if (!dev || !dev->bus)
504                 return_VOID;
505
506         pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
507         if (!pin)
508                 return_VOID;
509         pin--;
510
511         /*
512          * First we check the PCI IRQ routing table (PRT) for an IRQ.
513          */
514         gsi = acpi_pci_irq_lookup(dev->bus, PCI_SLOT(dev->devfn), pin,
515                                   &edge_level, &active_high_low, NULL,
516                                   acpi_pci_free_irq);
517         /*
518          * If no PRT entry was found, we'll try to derive an IRQ from the
519          * device's parent bridge.
520          */
521         if (gsi < 0)
522                 gsi = acpi_pci_irq_derive(dev, pin,
523                                           &edge_level, &active_high_low, NULL,
524                                           acpi_pci_free_irq);
525         if (gsi < 0)
526                 return_VOID;
527
528         /*
529          * TBD: It might be worth clearing dev->irq by magic constant
530          * (e.g. PCI_UNDEFINED_IRQ).
531          */
532
533         printk(KERN_INFO PREFIX "PCI interrupt for device %s disabled\n",
534                pci_name(dev));
535
536         acpi_unregister_gsi(gsi);
537
538         return_VOID;
539 }