ia64/linux-2.6.18-xen.hg

view drivers/acpi/pci_irq.c @ 912:dd42cdb0ab89

[IA64] Build blktap2 driver by default in x86 builds.

add CONFIG_XEN_BLKDEV_TAP2=y to buildconfigs/linux-defconfig_xen_ia64.

Signed-off-by: Isaku Yamahata <yamahata@valinux.co.jp>
author Isaku Yamahata <yamahata@valinux.co.jp>
date Mon Jun 29 12:09:16 2009 +0900 (2009-06-29)
parents 831230e53067
children
line source
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 */
28 #include <linux/kernel.h>
29 #include <linux/module.h>
30 #include <linux/init.h>
31 #include <linux/types.h>
32 #include <linux/proc_fs.h>
33 #include <linux/spinlock.h>
34 #include <linux/pm.h>
35 #include <linux/pci.h>
36 #include <linux/acpi.h>
37 #include <acpi/acpi_bus.h>
38 #include <acpi/acpi_drivers.h>
40 #define _COMPONENT ACPI_PCI_COMPONENT
41 ACPI_MODULE_NAME("pci_irq")
43 static struct acpi_prt_list acpi_prt;
44 static DEFINE_SPINLOCK(acpi_prt_lock);
46 /* --------------------------------------------------------------------------
47 PCI IRQ Routing Table (PRT) Support
48 -------------------------------------------------------------------------- */
50 static struct acpi_prt_entry *acpi_pci_irq_find_prt_entry(int segment,
51 int bus,
52 int device, int pin)
53 {
54 struct list_head *node = NULL;
55 struct acpi_prt_entry *entry = NULL;
58 if (!acpi_prt.count)
59 return NULL;
61 /*
62 * Parse through all PRT entries looking for a match on the specified
63 * PCI device's segment, bus, device, and pin (don't care about func).
64 *
65 */
66 spin_lock(&acpi_prt_lock);
67 list_for_each(node, &acpi_prt.entries) {
68 entry = list_entry(node, struct acpi_prt_entry, node);
69 if ((segment == entry->id.segment)
70 && (bus == entry->id.bus)
71 && (device == entry->id.device)
72 && (pin == entry->pin)) {
73 spin_unlock(&acpi_prt_lock);
74 return entry;
75 }
76 }
78 spin_unlock(&acpi_prt_lock);
79 return NULL;
80 }
82 static int
83 acpi_pci_irq_add_entry(acpi_handle handle,
84 int segment, int bus, struct acpi_pci_routing_table *prt)
85 {
86 struct acpi_prt_entry *entry = NULL;
89 if (!prt)
90 return -EINVAL;
92 entry = kmalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL);
93 if (!entry)
94 return -ENOMEM;
95 memset(entry, 0, sizeof(struct acpi_prt_entry));
97 entry->id.segment = segment;
98 entry->id.bus = bus;
99 entry->id.device = (prt->address >> 16) & 0xFFFF;
100 entry->id.function = prt->address & 0xFFFF;
101 entry->pin = prt->pin;
103 /*
104 * Type 1: Dynamic
105 * ---------------
106 * The 'source' field specifies the PCI interrupt link device used to
107 * configure the IRQ assigned to this slot|dev|pin. The 'source_index'
108 * indicates which resource descriptor in the resource template (of
109 * the link device) this interrupt is allocated from.
110 *
111 * NOTE: Don't query the Link Device for IRQ information at this time
112 * because Link Device enumeration may not have occurred yet
113 * (e.g. exists somewhere 'below' this _PRT entry in the ACPI
114 * namespace).
115 */
116 if (prt->source[0]) {
117 acpi_get_handle(handle, prt->source, &entry->link.handle);
118 entry->link.index = prt->source_index;
119 }
120 /*
121 * Type 2: Static
122 * --------------
123 * The 'source' field is NULL, and the 'source_index' field specifies
124 * the IRQ value, which is hardwired to specific interrupt inputs on
125 * the interrupt controller.
126 */
127 else
128 entry->link.index = prt->source_index;
130 ACPI_DEBUG_PRINT_RAW((ACPI_DB_INFO,
131 " %02X:%02X:%02X[%c] -> %s[%d]\n",
132 entry->id.segment, entry->id.bus,
133 entry->id.device, ('A' + entry->pin), prt->source,
134 entry->link.index));
136 spin_lock(&acpi_prt_lock);
137 list_add_tail(&entry->node, &acpi_prt.entries);
138 acpi_prt.count++;
139 spin_unlock(&acpi_prt_lock);
141 return 0;
142 }
144 static void
145 acpi_pci_irq_del_entry(int segment, int bus, struct acpi_prt_entry *entry)
146 {
147 if (segment == entry->id.segment && bus == entry->id.bus) {
148 acpi_prt.count--;
149 list_del(&entry->node);
150 kfree(entry);
151 }
152 }
154 int acpi_pci_irq_add_prt(acpi_handle handle, int segment, int bus)
155 {
156 acpi_status status = AE_OK;
157 char *pathname = NULL;
158 struct acpi_buffer buffer = { 0, NULL };
159 struct acpi_pci_routing_table *prt = NULL;
160 struct acpi_pci_routing_table *entry = NULL;
161 static int first_time = 1;
164 pathname = (char *)kmalloc(ACPI_PATHNAME_MAX, GFP_KERNEL);
165 if (!pathname)
166 return -ENOMEM;
167 memset(pathname, 0, ACPI_PATHNAME_MAX);
169 if (first_time) {
170 acpi_prt.count = 0;
171 INIT_LIST_HEAD(&acpi_prt.entries);
172 first_time = 0;
173 }
175 /*
176 * NOTE: We're given a 'handle' to the _PRT object's parent device
177 * (either a PCI root bridge or PCI-PCI bridge).
178 */
180 buffer.length = ACPI_PATHNAME_MAX;
181 buffer.pointer = pathname;
182 acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
184 printk(KERN_DEBUG "ACPI: PCI Interrupt Routing Table [%s._PRT]\n",
185 pathname);
187 /*
188 * Evaluate this _PRT and add its entries to our global list (acpi_prt).
189 */
191 buffer.length = 0;
192 buffer.pointer = NULL;
193 kfree(pathname);
194 status = acpi_get_irq_routing_table(handle, &buffer);
195 if (status != AE_BUFFER_OVERFLOW) {
196 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRT [%s]",
197 acpi_format_exception(status)));
198 return -ENODEV;
199 }
201 prt = kmalloc(buffer.length, GFP_KERNEL);
202 if (!prt) {
203 return -ENOMEM;
204 }
205 memset(prt, 0, buffer.length);
206 buffer.pointer = prt;
208 status = acpi_get_irq_routing_table(handle, &buffer);
209 if (ACPI_FAILURE(status)) {
210 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRT [%s]",
211 acpi_format_exception(status)));
212 kfree(buffer.pointer);
213 return -ENODEV;
214 }
216 entry = prt;
218 while (entry && (entry->length > 0)) {
219 acpi_pci_irq_add_entry(handle, segment, bus, entry);
220 entry = (struct acpi_pci_routing_table *)
221 ((unsigned long)entry + entry->length);
222 }
224 kfree(prt);
226 return 0;
227 }
229 void acpi_pci_irq_del_prt(int segment, int bus)
230 {
231 struct list_head *node = NULL, *n = NULL;
232 struct acpi_prt_entry *entry = NULL;
234 if (!acpi_prt.count) {
235 return;
236 }
238 printk(KERN_DEBUG
239 "ACPI: Delete PCI Interrupt Routing Table for %x:%x\n", segment,
240 bus);
241 spin_lock(&acpi_prt_lock);
242 list_for_each_safe(node, n, &acpi_prt.entries) {
243 entry = list_entry(node, struct acpi_prt_entry, node);
245 acpi_pci_irq_del_entry(segment, bus, entry);
246 }
247 spin_unlock(&acpi_prt_lock);
248 }
250 /* --------------------------------------------------------------------------
251 PCI Interrupt Routing Support
252 -------------------------------------------------------------------------- */
253 typedef int (*irq_lookup_func) (struct acpi_prt_entry *, int *, int *, char **);
255 static int
256 acpi_pci_allocate_irq(struct acpi_prt_entry *entry,
257 int *triggering, int *polarity, char **link)
258 {
259 int irq;
262 if (entry->link.handle) {
263 irq = acpi_pci_link_allocate_irq(entry->link.handle,
264 entry->link.index, triggering,
265 polarity, link);
266 if (irq < 0) {
267 printk(KERN_WARNING PREFIX
268 "Invalid IRQ link routing entry\n");
269 return -1;
270 }
271 } else {
272 irq = entry->link.index;
273 *triggering = ACPI_LEVEL_SENSITIVE;
274 *polarity = ACPI_ACTIVE_LOW;
275 }
277 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found IRQ %d\n", irq));
278 return irq;
279 }
281 static int
282 acpi_pci_free_irq(struct acpi_prt_entry *entry,
283 int *triggering, int *polarity, char **link)
284 {
285 int irq;
287 if (entry->link.handle) {
288 irq = acpi_pci_link_free_irq(entry->link.handle);
289 } else {
290 irq = entry->link.index;
291 }
292 return irq;
293 }
295 /*
296 * acpi_pci_irq_lookup
297 * success: return IRQ >= 0
298 * failure: return -1
299 */
300 static int
301 acpi_pci_irq_lookup(struct pci_bus *bus,
302 int device,
303 int pin,
304 int *triggering,
305 int *polarity, char **link, irq_lookup_func func)
306 {
307 struct acpi_prt_entry *entry = NULL;
308 int segment = pci_domain_nr(bus);
309 int bus_nr = bus->number;
310 int ret;
313 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
314 "Searching for PRT entry for %02x:%02x:%02x[%c]\n",
315 segment, bus_nr, device, ('A' + pin)));
317 entry = acpi_pci_irq_find_prt_entry(segment, bus_nr, device, pin);
318 if (!entry) {
319 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "PRT entry not found\n"));
320 return -1;
321 }
323 ret = func(entry, triggering, polarity, link);
324 return ret;
325 }
327 /*
328 * acpi_pci_irq_derive
329 * success: return IRQ >= 0
330 * failure: return < 0
331 */
332 static int
333 acpi_pci_irq_derive(struct pci_dev *dev,
334 int pin,
335 int *triggering,
336 int *polarity, char **link, irq_lookup_func func)
337 {
338 struct pci_dev *bridge = dev;
339 int irq = -1;
340 u8 bridge_pin = 0;
343 if (!dev)
344 return -EINVAL;
346 /*
347 * Attempt to derive an IRQ for this device from a parent bridge's
348 * PCI interrupt routing entry (eg. yenta bridge and add-in card bridge).
349 */
350 while (irq < 0 && bridge->bus->self) {
351 pin = (pin + PCI_SLOT(bridge->devfn)) % 4;
352 bridge = bridge->bus->self;
354 if ((bridge->class >> 8) == PCI_CLASS_BRIDGE_CARDBUS) {
355 /* PC card has the same IRQ as its cardbridge */
356 bridge_pin = bridge->pin;
357 if (!bridge_pin) {
358 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
359 "No interrupt pin configured for device %s\n",
360 pci_name(bridge)));
361 return -1;
362 }
363 /* Pin is from 0 to 3 */
364 bridge_pin--;
365 pin = bridge_pin;
366 }
368 irq = acpi_pci_irq_lookup(bridge->bus, PCI_SLOT(bridge->devfn),
369 pin, triggering, polarity,
370 link, func);
371 }
373 if (irq < 0) {
374 printk(KERN_WARNING PREFIX "Unable to derive IRQ for device %s\n",
375 pci_name(dev));
376 return -1;
377 }
379 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Derive IRQ %d for device %s from %s\n",
380 irq, pci_name(dev), pci_name(bridge)));
382 return irq;
383 }
385 /*
386 * acpi_pci_irq_enable
387 * success: return 0
388 * failure: return < 0
389 */
391 int acpi_pci_irq_enable(struct pci_dev *dev)
392 {
393 int irq = 0;
394 u8 pin = 0;
395 int triggering = ACPI_LEVEL_SENSITIVE;
396 int polarity = ACPI_ACTIVE_LOW;
397 char *link = NULL;
398 int rc;
401 if (!dev)
402 return -EINVAL;
404 pin = dev->pin;
405 if (!pin) {
406 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
407 "No interrupt pin configured for device %s\n",
408 pci_name(dev)));
409 return 0;
410 }
411 pin--;
413 if (!dev->bus) {
414 printk(KERN_ERR PREFIX "Invalid (NULL) 'bus' field\n");
415 return -ENODEV;
416 }
418 /*
419 * First we check the PCI IRQ routing table (PRT) for an IRQ. PRT
420 * values override any BIOS-assigned IRQs set during boot.
421 */
422 irq = acpi_pci_irq_lookup(dev->bus, PCI_SLOT(dev->devfn), pin,
423 &triggering, &polarity, &link,
424 acpi_pci_allocate_irq);
426 /*
427 * If no PRT entry was found, we'll try to derive an IRQ from the
428 * device's parent bridge.
429 */
430 if (irq < 0)
431 irq = acpi_pci_irq_derive(dev, pin, &triggering,
432 &polarity, &link,
433 acpi_pci_allocate_irq);
435 /*
436 * No IRQ known to the ACPI subsystem - maybe the BIOS /
437 * driver reported one, then use it. Exit in any case.
438 */
439 if (irq < 0) {
440 printk(KERN_WARNING PREFIX "PCI Interrupt %s[%c]: no GSI",
441 pci_name(dev), ('A' + pin));
442 /* Interrupt Line values above 0xF are forbidden */
443 if (dev->irq > 0 && (dev->irq <= 0xF)) {
444 printk(" - using IRQ %d\n", dev->irq);
445 acpi_register_gsi(dev->irq, ACPI_LEVEL_SENSITIVE,
446 ACPI_ACTIVE_LOW);
447 return 0;
448 } else {
449 printk("\n");
450 return 0;
451 }
452 }
454 rc = acpi_register_gsi(irq, triggering, polarity);
455 if (rc < 0) {
456 printk(KERN_WARNING PREFIX "PCI Interrupt %s[%c]: failed "
457 "to register GSI\n", pci_name(dev), ('A' + pin));
458 return rc;
459 }
460 dev->irq = rc;
462 printk(KERN_INFO PREFIX "PCI Interrupt %s[%c] -> ",
463 pci_name(dev), 'A' + pin);
465 if (link)
466 printk("Link [%s] -> ", link);
468 printk("GSI %u (%s, %s) -> IRQ %d\n", irq,
469 (triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge",
470 (polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq);
472 return 0;
473 }
475 EXPORT_SYMBOL(acpi_pci_irq_enable);
477 /* FIXME: implement x86/x86_64 version */
478 void __attribute__ ((weak)) acpi_unregister_gsi(u32 i)
479 {
480 }
482 void acpi_pci_irq_disable(struct pci_dev *dev)
483 {
484 int gsi = 0;
485 u8 pin = 0;
486 int triggering = ACPI_LEVEL_SENSITIVE;
487 int polarity = ACPI_ACTIVE_LOW;
490 if (!dev || !dev->bus)
491 return;
493 pin = dev->pin;
494 if (!pin)
495 return;
496 pin--;
498 /*
499 * First we check the PCI IRQ routing table (PRT) for an IRQ.
500 */
501 gsi = acpi_pci_irq_lookup(dev->bus, PCI_SLOT(dev->devfn), pin,
502 &triggering, &polarity, NULL,
503 acpi_pci_free_irq);
504 /*
505 * If no PRT entry was found, we'll try to derive an IRQ from the
506 * device's parent bridge.
507 */
508 if (gsi < 0)
509 gsi = acpi_pci_irq_derive(dev, pin,
510 &triggering, &polarity, NULL,
511 acpi_pci_free_irq);
512 if (gsi < 0)
513 return;
515 /*
516 * TBD: It might be worth clearing dev->irq by magic constant
517 * (e.g. PCI_UNDEFINED_IRQ).
518 */
520 printk(KERN_INFO PREFIX "PCI interrupt for device %s disabled\n",
521 pci_name(dev));
523 acpi_unregister_gsi(gsi);
525 return;
526 }