[PATCH] VIA IRQ quirk
[linux-3.10.git] / 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
42 #define _COMPONENT              ACPI_PCI_COMPONENT
43 ACPI_MODULE_NAME                ("pci_irq")
44
45 static struct acpi_prt_list     acpi_prt;
46 static DEFINE_SPINLOCK(acpi_prt_lock);
47
48 /* --------------------------------------------------------------------------
49                          PCI IRQ Routing Table (PRT) Support
50    -------------------------------------------------------------------------- */
51
52 static struct acpi_prt_entry *
53 acpi_pci_irq_find_prt_entry (
54         int                     segment,
55         int                     bus,
56         int                     device,
57         int                     pin)
58 {
59         struct list_head        *node = NULL;
60         struct acpi_prt_entry   *entry = NULL;
61
62         ACPI_FUNCTION_TRACE("acpi_pci_irq_find_prt_entry");
63
64         if (!acpi_prt.count)
65                 return_PTR(NULL);
66
67         /*
68          * Parse through all PRT entries looking for a match on the specified
69          * PCI device's segment, bus, device, and pin (don't care about func).
70          *
71          */
72         spin_lock(&acpi_prt_lock);
73         list_for_each(node, &acpi_prt.entries) {
74                 entry = list_entry(node, struct acpi_prt_entry, node);
75                 if ((segment == entry->id.segment) 
76                         && (bus == entry->id.bus) 
77                         && (device == entry->id.device)
78                         && (pin == entry->pin)) {
79                         spin_unlock(&acpi_prt_lock);
80                         return_PTR(entry);
81                 }
82         }
83
84         spin_unlock(&acpi_prt_lock);
85         return_PTR(NULL);
86 }
87
88
89 static int
90 acpi_pci_irq_add_entry (
91         acpi_handle                     handle,
92         int                             segment,
93         int                             bus,
94         struct acpi_pci_routing_table   *prt)
95 {
96         struct acpi_prt_entry   *entry = NULL;
97
98         ACPI_FUNCTION_TRACE("acpi_pci_irq_add_entry");
99
100         if (!prt)
101                 return_VALUE(-EINVAL);
102
103         entry = kmalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL);
104         if (!entry)
105                 return_VALUE(-ENOMEM);
106         memset(entry, 0, sizeof(struct acpi_prt_entry));
107
108         entry->id.segment = segment;
109         entry->id.bus = bus;
110         entry->id.device = (prt->address >> 16) & 0xFFFF;
111         entry->id.function = prt->address & 0xFFFF;
112         entry->pin = prt->pin;
113
114         /*
115          * Type 1: Dynamic
116          * ---------------
117          * The 'source' field specifies the PCI interrupt link device used to
118          * configure the IRQ assigned to this slot|dev|pin.  The 'source_index'
119          * indicates which resource descriptor in the resource template (of
120          * the link device) this interrupt is allocated from.
121          * 
122          * NOTE: Don't query the Link Device for IRQ information at this time
123          *       because Link Device enumeration may not have occurred yet
124          *       (e.g. exists somewhere 'below' this _PRT entry in the ACPI
125          *       namespace).
126          */
127         if (prt->source[0]) {
128                 acpi_get_handle(handle, prt->source, &entry->link.handle);
129                 entry->link.index = prt->source_index;
130         }
131         /*
132          * Type 2: Static
133          * --------------
134          * The 'source' field is NULL, and the 'source_index' field specifies
135          * the IRQ value, which is hardwired to specific interrupt inputs on
136          * the interrupt controller.
137          */
138         else
139                 entry->link.index = prt->source_index;
140
141         ACPI_DEBUG_PRINT_RAW((ACPI_DB_INFO,
142                 "      %02X:%02X:%02X[%c] -> %s[%d]\n", 
143                 entry->id.segment, entry->id.bus, entry->id.device, 
144                 ('A' + entry->pin), prt->source, entry->link.index));
145
146         spin_lock(&acpi_prt_lock);
147         list_add_tail(&entry->node, &acpi_prt.entries);
148         acpi_prt.count++;
149         spin_unlock(&acpi_prt_lock);
150
151         return_VALUE(0);
152 }
153
154
155 static void
156 acpi_pci_irq_del_entry (
157         int                             segment,
158         int                             bus,
159         struct acpi_prt_entry           *entry)
160 {
161         if (segment == entry->id.segment && bus == entry->id.bus){
162                 acpi_prt.count--;
163                 list_del(&entry->node);
164                 kfree(entry);
165         }
166 }
167
168
169 int
170 acpi_pci_irq_add_prt (
171         acpi_handle             handle,
172         int                     segment,
173         int                     bus)
174 {
175         acpi_status                     status = AE_OK;
176         char                            *pathname = NULL;
177         struct acpi_buffer              buffer = {0, NULL};
178         struct acpi_pci_routing_table   *prt = NULL;
179         struct acpi_pci_routing_table   *entry = NULL;
180         static int                      first_time = 1;
181
182         ACPI_FUNCTION_TRACE("acpi_pci_irq_add_prt");
183
184         pathname = (char *) kmalloc(ACPI_PATHNAME_MAX, GFP_KERNEL);
185         if(!pathname)
186                 return_VALUE(-ENOMEM);
187         memset(pathname, 0, ACPI_PATHNAME_MAX);
188
189         if (first_time) {
190                 acpi_prt.count = 0;
191                 INIT_LIST_HEAD(&acpi_prt.entries);
192                 first_time = 0;
193         }
194
195         /* 
196          * NOTE: We're given a 'handle' to the _PRT object's parent device
197          *       (either a PCI root bridge or PCI-PCI bridge).
198          */
199
200         buffer.length = ACPI_PATHNAME_MAX;
201         buffer.pointer = pathname;
202         acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
203
204         printk(KERN_DEBUG "ACPI: PCI Interrupt Routing Table [%s._PRT]\n",
205                 pathname);
206
207         /* 
208          * Evaluate this _PRT and add its entries to our global list (acpi_prt).
209          */
210
211         buffer.length = 0;
212         buffer.pointer = NULL;
213         kfree(pathname);
214         status = acpi_get_irq_routing_table(handle, &buffer);
215         if (status != AE_BUFFER_OVERFLOW) {
216                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PRT [%s]\n",
217                         acpi_format_exception(status)));
218                 return_VALUE(-ENODEV);
219         }
220
221         prt = kmalloc(buffer.length, GFP_KERNEL);
222         if (!prt){
223                 return_VALUE(-ENOMEM);
224         }
225         memset(prt, 0, buffer.length);
226         buffer.pointer = prt;
227
228         status = acpi_get_irq_routing_table(handle, &buffer);
229         if (ACPI_FAILURE(status)) {
230                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Error evaluating _PRT [%s]\n",
231                         acpi_format_exception(status)));
232                 kfree(buffer.pointer);
233                 return_VALUE(-ENODEV);
234         }
235
236         entry = prt;
237
238         while (entry && (entry->length > 0)) {
239                 acpi_pci_irq_add_entry(handle, segment, bus, entry);
240                 entry = (struct acpi_pci_routing_table *)
241                         ((unsigned long) entry + entry->length);
242         }
243
244         kfree(prt);
245
246         return_VALUE(0);
247 }
248
249 void
250 acpi_pci_irq_del_prt (int segment, int bus)
251 {
252         struct list_head        *node = NULL, *n = NULL;
253         struct acpi_prt_entry   *entry = NULL;
254
255         if (!acpi_prt.count)    {
256                 return;
257         }
258
259         printk(KERN_DEBUG "ACPI: Delete PCI Interrupt Routing Table for %x:%x\n",
260                 segment, bus);
261         spin_lock(&acpi_prt_lock);
262         list_for_each_safe(node, n, &acpi_prt.entries) {
263                 entry = list_entry(node, struct acpi_prt_entry, node);
264
265                 acpi_pci_irq_del_entry(segment, bus, entry);
266         }
267         spin_unlock(&acpi_prt_lock);
268 }
269 /* --------------------------------------------------------------------------
270                           PCI Interrupt Routing Support
271    -------------------------------------------------------------------------- */
272
273 /*
274  * acpi_pci_irq_lookup
275  * success: return IRQ >= 0
276  * failure: return -1
277  */
278 static int
279 acpi_pci_irq_lookup (
280         struct pci_bus          *bus,
281         int                     device,
282         int                     pin,
283         int                     *edge_level,
284         int                     *active_high_low,
285         char                    **link)
286 {
287         struct acpi_prt_entry   *entry = NULL;
288         int segment = pci_domain_nr(bus);
289         int bus_nr = bus->number;
290         int irq;
291
292         ACPI_FUNCTION_TRACE("acpi_pci_irq_lookup");
293
294         ACPI_DEBUG_PRINT((ACPI_DB_INFO, 
295                 "Searching for PRT entry for %02x:%02x:%02x[%c]\n", 
296                 segment, bus_nr, device, ('A' + pin)));
297
298         entry = acpi_pci_irq_find_prt_entry(segment, bus_nr, device, pin); 
299         if (!entry) {
300                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PRT entry not found\n"));
301                 return_VALUE(-1);
302         }
303         
304         if (entry->link.handle) {
305                 irq = acpi_pci_link_get_irq(entry->link.handle,
306                         entry->link.index, edge_level, active_high_low, link);
307                 if (irq < 0) {
308                         ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Invalid IRQ link routing entry\n"));
309                         return_VALUE(-1);
310                 }
311         } else {
312                 irq = entry->link.index;
313                 *edge_level = ACPI_LEVEL_SENSITIVE;
314                 *active_high_low = ACPI_ACTIVE_LOW;
315         }
316
317         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found IRQ %d\n", irq));
318
319         return_VALUE(irq);
320 }
321
322 /*
323  * acpi_pci_irq_derive
324  * success: return IRQ >= 0
325  * failure: return < 0
326  */
327 static int
328 acpi_pci_irq_derive (
329         struct pci_dev          *dev,
330         int                     pin,
331         int                     *edge_level,
332         int                     *active_high_low,
333         char                    **link)
334 {
335         struct pci_dev          *bridge = dev;
336         int                     irq = -1;
337         u8                      bridge_pin = 0;
338
339         ACPI_FUNCTION_TRACE("acpi_pci_irq_derive");
340
341         if (!dev)
342                 return_VALUE(-EINVAL);
343
344         /* 
345          * Attempt to derive an IRQ for this device from a parent bridge's
346          * PCI interrupt routing entry (eg. yenta bridge and add-in card bridge).
347          */
348         while (irq < 0 && bridge->bus->self) {
349                 pin = (pin + PCI_SLOT(bridge->devfn)) % 4;
350                 bridge = bridge->bus->self;
351
352                 if ((bridge->class >> 8) == PCI_CLASS_BRIDGE_CARDBUS) {
353                         /* PC card has the same IRQ as its cardbridge */
354                         pci_read_config_byte(bridge, PCI_INTERRUPT_PIN, &bridge_pin);
355                         if (!bridge_pin) {
356                                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, 
357                                         "No interrupt pin configured for device %s\n", pci_name(bridge)));
358                                 return_VALUE(-1);
359                         }
360                         /* Pin is from 0 to 3 */
361                         bridge_pin --;
362                         pin = bridge_pin;
363                 }
364
365                 irq = acpi_pci_irq_lookup(bridge->bus, PCI_SLOT(bridge->devfn),
366                         pin, edge_level, active_high_low, link);
367         }
368
369         if (irq < 0) {
370                 ACPI_DEBUG_PRINT((ACPI_DB_WARN, "Unable to derive IRQ for device %s\n", pci_name(dev)));
371                 return_VALUE(-1);
372         }
373
374         ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Derive IRQ %d for device %s from %s\n",
375                 irq, pci_name(dev), pci_name(bridge)));
376
377         return_VALUE(irq);
378 }
379
380 /*
381  * acpi_pci_irq_enable
382  * success: return 0
383  * failure: return < 0
384  */
385
386 int
387 acpi_pci_irq_enable (
388         struct pci_dev          *dev)
389 {
390         int                     irq = 0;
391         u8                      pin = 0;
392         int                     edge_level = ACPI_LEVEL_SENSITIVE;
393         int                     active_high_low = ACPI_ACTIVE_LOW;
394         char                    *link = NULL;
395
396         ACPI_FUNCTION_TRACE("acpi_pci_irq_enable");
397
398         if (!dev)
399                 return_VALUE(-EINVAL);
400         
401         pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
402         if (!pin) {
403                 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "No interrupt pin configured for device %s\n", pci_name(dev)));
404                 return_VALUE(0);
405         }
406         pin--;
407
408         if (!dev->bus) {
409                 ACPI_DEBUG_PRINT((ACPI_DB_ERROR, "Invalid (NULL) 'bus' field\n"));
410                 return_VALUE(-ENODEV);
411         }
412
413         /* 
414          * First we check the PCI IRQ routing table (PRT) for an IRQ.  PRT
415          * values override any BIOS-assigned IRQs set during boot.
416          */
417         irq = acpi_pci_irq_lookup(dev->bus, PCI_SLOT(dev->devfn), pin,
418                 &edge_level, &active_high_low, &link);
419
420         /*
421          * If no PRT entry was found, we'll try to derive an IRQ from the
422          * device's parent bridge.
423          */
424         if (irq < 0)
425                 irq = acpi_pci_irq_derive(dev, pin, &edge_level,
426                         &active_high_low, &link);
427  
428         /*
429          * No IRQ known to the ACPI subsystem - maybe the BIOS / 
430          * driver reported one, then use it. Exit in any case.
431          */
432         if (irq < 0) {
433                 printk(KERN_WARNING PREFIX "PCI Interrupt %s[%c]: no GSI",
434                         pci_name(dev), ('A' + pin));
435                 /* Interrupt Line values above 0xF are forbidden */
436                 if (dev->irq >= 0 && (dev->irq <= 0xF)) {
437                         printk(" - using IRQ %d\n", dev->irq);
438                         return_VALUE(0);
439                 }
440                 else {
441                         printk("\n");
442                         return_VALUE(0);
443                 }
444         }
445
446         dev->irq = acpi_register_gsi(irq, edge_level, active_high_low);
447
448         printk(KERN_INFO PREFIX "PCI Interrupt %s[%c] -> ",
449                 pci_name(dev), 'A' + pin);
450
451         if (link)
452                 printk("Link [%s] -> ", link);
453
454         printk("GSI %u (%s, %s) -> IRQ %d\n", irq,
455                 (edge_level == ACPI_LEVEL_SENSITIVE) ? "level" : "edge",
456                 (active_high_low == ACPI_ACTIVE_LOW) ? "low" : "high",
457                 dev->irq);
458
459         return_VALUE(0);
460 }
461 EXPORT_SYMBOL(acpi_pci_irq_enable);
462
463
464 #ifdef CONFIG_ACPI_DEALLOCATE_IRQ
465 void
466 acpi_pci_irq_disable (
467         struct pci_dev          *dev)
468 {
469         int                     gsi = 0;
470         u8                      pin = 0;
471         int                     edge_level = ACPI_LEVEL_SENSITIVE;
472         int                     active_high_low = ACPI_ACTIVE_LOW;
473
474         ACPI_FUNCTION_TRACE("acpi_pci_irq_disable");
475
476         if (!dev)
477                 return_VOID;
478
479         pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
480         if (!pin)
481                 return_VOID;
482         pin--;
483
484         if (!dev->bus)
485                 return_VOID;
486
487         /*
488          * First we check the PCI IRQ routing table (PRT) for an IRQ.
489          */
490         gsi = acpi_pci_irq_lookup(dev->bus, PCI_SLOT(dev->devfn), pin,
491                                   &edge_level, &active_high_low, NULL);
492         /*
493          * If no PRT entry was found, we'll try to derive an IRQ from the
494          * device's parent bridge.
495          */
496         if (gsi < 0)
497                 gsi = acpi_pci_irq_derive(dev, pin,
498                                           &edge_level, &active_high_low, NULL);
499         if (gsi < 0)
500                 return_VOID;
501
502         /*
503          * TBD: It might be worth clearing dev->irq by magic constant
504          * (e.g. PCI_UNDEFINED_IRQ).
505          */
506
507         printk(KERN_INFO PREFIX "PCI interrupt for device %s disabled\n",
508                pci_name(dev));
509
510         acpi_unregister_gsi(gsi);
511
512         return_VOID;
513 }
514 #endif /* CONFIG_ACPI_DEALLOCATE_IRQ */