2 * pci_irq.c - ACPI PCI Interrupt Routing ($Revision: 11 $)
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>
8 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
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.
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.
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.
24 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
27 #include <linux/config.h>
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>
36 #include <linux/pci.h>
37 #include <linux/acpi.h>
38 #include <acpi/acpi_bus.h>
39 #include <acpi/acpi_drivers.h>
41 #define _COMPONENT ACPI_PCI_COMPONENT
42 ACPI_MODULE_NAME("pci_irq")
44 static struct acpi_prt_list acpi_prt
;
45 static DEFINE_SPINLOCK(acpi_prt_lock
);
47 /* --------------------------------------------------------------------------
48 PCI IRQ Routing Table (PRT) Support
49 -------------------------------------------------------------------------- */
51 static struct acpi_prt_entry
*acpi_pci_irq_find_prt_entry(int segment
,
55 struct list_head
*node
= NULL
;
56 struct acpi_prt_entry
*entry
= NULL
;
58 ACPI_FUNCTION_TRACE("acpi_pci_irq_find_prt_entry");
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).
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
);
80 spin_unlock(&acpi_prt_lock
);
85 acpi_pci_irq_add_entry(acpi_handle handle
,
86 int segment
, int bus
, struct acpi_pci_routing_table
*prt
)
88 struct acpi_prt_entry
*entry
= NULL
;
90 ACPI_FUNCTION_TRACE("acpi_pci_irq_add_entry");
93 return_VALUE(-EINVAL
);
95 entry
= kmalloc(sizeof(struct acpi_prt_entry
), GFP_KERNEL
);
97 return_VALUE(-ENOMEM
);
98 memset(entry
, 0, sizeof(struct acpi_prt_entry
));
100 entry
->id
.segment
= segment
;
102 entry
->id
.device
= (prt
->address
>> 16) & 0xFFFF;
103 entry
->id
.function
= prt
->address
& 0xFFFF;
104 entry
->pin
= prt
->pin
;
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.
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
119 if (prt
->source
[0]) {
120 acpi_get_handle(handle
, prt
->source
, &entry
->link
.handle
);
121 entry
->link
.index
= prt
->source_index
;
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.
131 entry
->link
.index
= prt
->source_index
;
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
,
139 spin_lock(&acpi_prt_lock
);
140 list_add_tail(&entry
->node
, &acpi_prt
.entries
);
142 spin_unlock(&acpi_prt_lock
);
148 acpi_pci_irq_del_entry(int segment
, int bus
, struct acpi_prt_entry
*entry
)
150 if (segment
== entry
->id
.segment
&& bus
== entry
->id
.bus
) {
152 list_del(&entry
->node
);
157 int acpi_pci_irq_add_prt(acpi_handle handle
, int segment
, int bus
)
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;
166 ACPI_FUNCTION_TRACE("acpi_pci_irq_add_prt");
168 pathname
= (char *)kmalloc(ACPI_PATHNAME_MAX
, GFP_KERNEL
);
170 return_VALUE(-ENOMEM
);
171 memset(pathname
, 0, ACPI_PATHNAME_MAX
);
175 INIT_LIST_HEAD(&acpi_prt
.entries
);
180 * NOTE: We're given a 'handle' to the _PRT object's parent device
181 * (either a PCI root bridge or PCI-PCI bridge).
184 buffer
.length
= ACPI_PATHNAME_MAX
;
185 buffer
.pointer
= pathname
;
186 acpi_get_name(handle
, ACPI_FULL_PATHNAME
, &buffer
);
188 printk(KERN_DEBUG
"ACPI: PCI Interrupt Routing Table [%s._PRT]\n",
192 * Evaluate this _PRT and add its entries to our global list (acpi_prt).
196 buffer
.pointer
= NULL
;
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
);
205 prt
= kmalloc(buffer
.length
, GFP_KERNEL
);
207 return_VALUE(-ENOMEM
);
209 memset(prt
, 0, buffer
.length
);
210 buffer
.pointer
= prt
;
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
);
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
);
233 void acpi_pci_irq_del_prt(int segment
, int bus
)
235 struct list_head
*node
= NULL
, *n
= NULL
;
236 struct acpi_prt_entry
*entry
= NULL
;
238 if (!acpi_prt
.count
) {
243 "ACPI: Delete PCI Interrupt Routing Table for %x:%x\n", segment
,
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
);
249 acpi_pci_irq_del_entry(segment
, bus
, entry
);
251 spin_unlock(&acpi_prt_lock
);
254 /* --------------------------------------------------------------------------
255 PCI Interrupt Routing Support
256 -------------------------------------------------------------------------- */
257 typedef int (*irq_lookup_func
) (struct acpi_prt_entry
*, int *, int *, char **);
260 acpi_pci_allocate_irq(struct acpi_prt_entry
*entry
,
261 int *edge_level
, int *active_high_low
, char **link
)
265 ACPI_FUNCTION_TRACE("acpi_pci_allocate_irq");
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
);
272 ACPI_DEBUG_PRINT((ACPI_DB_WARN
,
273 "Invalid IRQ link routing entry\n"));
277 irq
= entry
->link
.index
;
278 *edge_level
= ACPI_LEVEL_SENSITIVE
;
279 *active_high_low
= ACPI_ACTIVE_LOW
;
282 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Found IRQ %d\n", irq
));
287 acpi_pci_free_irq(struct acpi_prt_entry
*entry
,
288 int *edge_level
, int *active_high_low
, char **link
)
292 ACPI_FUNCTION_TRACE("acpi_pci_free_irq");
293 if (entry
->link
.handle
) {
294 irq
= acpi_pci_link_free_irq(entry
->link
.handle
);
296 irq
= entry
->link
.index
;
302 * acpi_pci_irq_lookup
303 * success: return IRQ >= 0
307 acpi_pci_irq_lookup(struct pci_bus
*bus
,
311 int *active_high_low
, char **link
, irq_lookup_func func
)
313 struct acpi_prt_entry
*entry
= NULL
;
314 int segment
= pci_domain_nr(bus
);
315 int bus_nr
= bus
->number
;
318 ACPI_FUNCTION_TRACE("acpi_pci_irq_lookup");
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
)));
324 entry
= acpi_pci_irq_find_prt_entry(segment
, bus_nr
, device
, pin
);
326 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "PRT entry not found\n"));
330 ret
= func(entry
, edge_level
, active_high_low
, link
);
335 * acpi_pci_irq_derive
336 * success: return IRQ >= 0
337 * failure: return < 0
340 acpi_pci_irq_derive(struct pci_dev
*dev
,
343 int *active_high_low
, char **link
, irq_lookup_func func
)
345 struct pci_dev
*bridge
= dev
;
349 ACPI_FUNCTION_TRACE("acpi_pci_irq_derive");
352 return_VALUE(-EINVAL
);
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).
358 while (irq
< 0 && bridge
->bus
->self
) {
359 pin
= (pin
+ PCI_SLOT(bridge
->devfn
)) % 4;
360 bridge
= bridge
->bus
->self
;
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
,
367 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
368 "No interrupt pin configured for device %s\n",
372 /* Pin is from 0 to 3 */
377 irq
= acpi_pci_irq_lookup(bridge
->bus
, PCI_SLOT(bridge
->devfn
),
378 pin
, edge_level
, active_high_low
,
383 ACPI_DEBUG_PRINT((ACPI_DB_WARN
,
384 "Unable to derive IRQ for device %s\n",
389 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Derive IRQ %d for device %s from %s\n",
390 irq
, pci_name(dev
), pci_name(bridge
)));
396 * acpi_pci_irq_enable
398 * failure: return < 0
401 int acpi_pci_irq_enable(struct pci_dev
*dev
)
405 int edge_level
= ACPI_LEVEL_SENSITIVE
;
406 int active_high_low
= ACPI_ACTIVE_LOW
;
410 ACPI_FUNCTION_TRACE("acpi_pci_irq_enable");
413 return_VALUE(-EINVAL
);
415 pci_read_config_byte(dev
, PCI_INTERRUPT_PIN
, &pin
);
417 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
418 "No interrupt pin configured for device %s\n",
425 ACPI_DEBUG_PRINT((ACPI_DB_ERROR
,
426 "Invalid (NULL) 'bus' field\n"));
427 return_VALUE(-ENODEV
);
431 * First we check the PCI IRQ routing table (PRT) for an IRQ. PRT
432 * values override any BIOS-assigned IRQs set during boot.
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
);
439 * If no PRT entry was found, we'll try to derive an IRQ from the
440 * device's parent bridge.
443 irq
= acpi_pci_irq_derive(dev
, pin
, &edge_level
,
444 &active_high_low
, &link
,
445 acpi_pci_allocate_irq
);
448 * No IRQ known to the ACPI subsystem - maybe the BIOS /
449 * driver reported one, then use it. Exit in any case.
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
,
466 rc
= acpi_register_gsi(irq
, edge_level
, active_high_low
);
468 printk(KERN_WARNING PREFIX
"PCI Interrupt %s[%c]: failed "
469 "to register GSI\n", pci_name(dev
), ('A' + pin
));
474 printk(KERN_INFO PREFIX
"PCI Interrupt %s[%c] -> ",
475 pci_name(dev
), 'A' + pin
);
478 printk("Link [%s] -> ", link
);
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
);
487 EXPORT_SYMBOL(acpi_pci_irq_enable
);
489 /* FIXME: implement x86/x86_64 version */
490 void __attribute__ ((weak
)) acpi_unregister_gsi(u32 i
)
494 void acpi_pci_irq_disable(struct pci_dev
*dev
)
498 int edge_level
= ACPI_LEVEL_SENSITIVE
;
499 int active_high_low
= ACPI_ACTIVE_LOW
;
501 ACPI_FUNCTION_TRACE("acpi_pci_irq_disable");
503 if (!dev
|| !dev
->bus
)
506 pci_read_config_byte(dev
, PCI_INTERRUPT_PIN
, &pin
);
512 * First we check the PCI IRQ routing table (PRT) for an IRQ.
514 gsi
= acpi_pci_irq_lookup(dev
->bus
, PCI_SLOT(dev
->devfn
), pin
,
515 &edge_level
, &active_high_low
, NULL
,
518 * If no PRT entry was found, we'll try to derive an IRQ from the
519 * device's parent bridge.
522 gsi
= acpi_pci_irq_derive(dev
, pin
,
523 &edge_level
, &active_high_low
, NULL
,
529 * TBD: It might be worth clearing dev->irq by magic constant
530 * (e.g. PCI_UNDEFINED_IRQ).
533 printk(KERN_INFO PREFIX
"PCI interrupt for device %s disabled\n",
536 acpi_unregister_gsi(gsi
);