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>
7 * (c) Copyright 2008 Hewlett-Packard Development Company, L.P.
8 * Bjorn Helgaas <bjorn.helgaas@hp.com>
10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU General Public License as published by
14 * the Free Software Foundation; either version 2 of the License, or (at
15 * your option) any later version.
17 * This program is distributed in the hope that it will be useful, but
18 * WITHOUT ANY WARRANTY; without even the implied warranty of
19 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
20 * General Public License for more details.
22 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
26 #include <linux/dmi.h>
27 #include <linux/kernel.h>
28 #include <linux/module.h>
29 #include <linux/init.h>
30 #include <linux/types.h>
31 #include <linux/spinlock.h>
33 #include <linux/pci.h>
34 #include <linux/acpi.h>
35 #include <linux/slab.h>
36 #include <linux/interrupt.h>
38 #define PREFIX "ACPI: "
40 #define _COMPONENT ACPI_PCI_COMPONENT
41 ACPI_MODULE_NAME("pci_irq");
43 struct acpi_prt_entry
{
44 struct acpi_pci_id id
;
47 u32 index
; /* GSI, or link _CRS index */
50 static inline char pin_name(int pin
)
55 /* --------------------------------------------------------------------------
56 PCI IRQ Routing Table (PRT) Support
57 -------------------------------------------------------------------------- */
59 /* http://bugzilla.kernel.org/show_bug.cgi?id=4773 */
60 static const struct dmi_system_id medion_md9580
[] = {
62 .ident
= "Medion MD9580-F laptop",
64 DMI_MATCH(DMI_SYS_VENDOR
, "MEDIONNB"),
65 DMI_MATCH(DMI_PRODUCT_NAME
, "A555"),
71 /* http://bugzilla.kernel.org/show_bug.cgi?id=5044 */
72 static const struct dmi_system_id dell_optiplex
[] = {
74 .ident
= "Dell Optiplex GX1",
76 DMI_MATCH(DMI_SYS_VENDOR
, "Dell Computer Corporation"),
77 DMI_MATCH(DMI_PRODUCT_NAME
, "OptiPlex GX1 600S+"),
83 /* http://bugzilla.kernel.org/show_bug.cgi?id=10138 */
84 static const struct dmi_system_id hp_t5710
[] = {
88 DMI_MATCH(DMI_SYS_VENDOR
, "Hewlett-Packard"),
89 DMI_MATCH(DMI_PRODUCT_NAME
, "hp t5000 series"),
90 DMI_MATCH(DMI_BOARD_NAME
, "098Ch"),
97 const struct dmi_system_id
*system
;
102 const char *source
; /* according to BIOS */
103 const char *actual_source
;
106 #define PCI_INTX_PIN(c) (c - 'A' + 1)
109 * These systems have incorrect _PRT entries. The BIOS claims the PCI
110 * interrupt at the listed segment/bus/device/pin is connected to the first
111 * link device, but it is actually connected to the second.
113 static const struct prt_quirk prt_quirks
[] = {
114 { medion_md9580
, 0, 0, 9, PCI_INTX_PIN('A'),
115 "\\_SB_.PCI0.ISA_.LNKA",
116 "\\_SB_.PCI0.ISA_.LNKB"},
117 { dell_optiplex
, 0, 0, 0xd, PCI_INTX_PIN('A'),
120 { hp_t5710
, 0, 0, 1, PCI_INTX_PIN('A'),
125 static void do_prt_fixups(struct acpi_prt_entry
*entry
,
126 struct acpi_pci_routing_table
*prt
)
129 const struct prt_quirk
*quirk
;
131 for (i
= 0; i
< ARRAY_SIZE(prt_quirks
); i
++) {
132 quirk
= &prt_quirks
[i
];
134 /* All current quirks involve link devices, not GSIs */
135 if (dmi_check_system(quirk
->system
) &&
136 entry
->id
.segment
== quirk
->segment
&&
137 entry
->id
.bus
== quirk
->bus
&&
138 entry
->id
.device
== quirk
->device
&&
139 entry
->pin
== quirk
->pin
&&
140 !strcmp(prt
->source
, quirk
->source
) &&
141 strlen(prt
->source
) >= strlen(quirk
->actual_source
)) {
142 printk(KERN_WARNING PREFIX
"firmware reports "
143 "%04x:%02x:%02x PCI INT %c connected to %s; "
145 entry
->id
.segment
, entry
->id
.bus
,
146 entry
->id
.device
, pin_name(entry
->pin
),
147 prt
->source
, quirk
->actual_source
);
148 strcpy(prt
->source
, quirk
->actual_source
);
153 static int acpi_pci_irq_check_entry(acpi_handle handle
, struct pci_dev
*dev
,
154 int pin
, struct acpi_pci_routing_table
*prt
,
155 struct acpi_prt_entry
**entry_ptr
)
157 int segment
= pci_domain_nr(dev
->bus
);
158 int bus
= dev
->bus
->number
;
159 int device
= pci_ari_enabled(dev
->bus
) ? 0 : PCI_SLOT(dev
->devfn
);
160 struct acpi_prt_entry
*entry
;
162 if (((prt
->address
>> 16) & 0xffff) != device
||
166 entry
= kzalloc(sizeof(struct acpi_prt_entry
), GFP_KERNEL
);
171 * Note that the _PRT uses 0=INTA, 1=INTB, etc, while PCI uses
172 * 1=INTA, 2=INTB. We use the PCI encoding throughout, so convert
175 entry
->id
.segment
= segment
;
177 entry
->id
.device
= (prt
->address
>> 16) & 0xFFFF;
178 entry
->pin
= prt
->pin
+ 1;
180 do_prt_fixups(entry
, prt
);
182 entry
->index
= prt
->source_index
;
187 * The 'source' field specifies the PCI interrupt link device used to
188 * configure the IRQ assigned to this slot|dev|pin. The 'source_index'
189 * indicates which resource descriptor in the resource template (of
190 * the link device) this interrupt is allocated from.
192 * NOTE: Don't query the Link Device for IRQ information at this time
193 * because Link Device enumeration may not have occurred yet
194 * (e.g. exists somewhere 'below' this _PRT entry in the ACPI
198 acpi_get_handle(handle
, prt
->source
, &entry
->link
);
203 * The 'source' field is NULL, and the 'source_index' field specifies
204 * the IRQ value, which is hardwired to specific interrupt inputs on
205 * the interrupt controller.
208 ACPI_DEBUG_PRINT_RAW((ACPI_DB_INFO
,
209 " %04x:%02x:%02x[%c] -> %s[%d]\n",
210 entry
->id
.segment
, entry
->id
.bus
,
211 entry
->id
.device
, pin_name(entry
->pin
),
212 prt
->source
, entry
->index
));
219 static int acpi_pci_irq_find_prt_entry(struct pci_dev
*dev
,
220 int pin
, struct acpi_prt_entry
**entry_ptr
)
223 struct acpi_buffer buffer
= { ACPI_ALLOCATE_BUFFER
, NULL
};
224 struct acpi_pci_routing_table
*entry
;
225 acpi_handle handle
= NULL
;
227 if (dev
->bus
->bridge
)
228 handle
= ACPI_HANDLE(dev
->bus
->bridge
);
233 /* 'handle' is the _PRT's parent (root bridge or PCI-PCI bridge) */
234 status
= acpi_get_irq_routing_table(handle
, &buffer
);
235 if (ACPI_FAILURE(status
)) {
236 kfree(buffer
.pointer
);
240 entry
= buffer
.pointer
;
241 while (entry
&& (entry
->length
> 0)) {
242 if (!acpi_pci_irq_check_entry(handle
, dev
, pin
,
245 entry
= (struct acpi_pci_routing_table
*)
246 ((unsigned long)entry
+ entry
->length
);
249 kfree(buffer
.pointer
);
253 /* --------------------------------------------------------------------------
254 PCI Interrupt Routing Support
255 -------------------------------------------------------------------------- */
256 #ifdef CONFIG_X86_IO_APIC
257 extern int noioapicquirk
;
258 extern int noioapicreroute
;
260 static int bridge_has_boot_interrupt_variant(struct pci_bus
*bus
)
262 struct pci_bus
*bus_it
;
264 for (bus_it
= bus
; bus_it
; bus_it
= bus_it
->parent
) {
267 if (bus_it
->self
->irq_reroute_variant
)
268 return bus_it
->self
->irq_reroute_variant
;
274 * Some chipsets (e.g. Intel 6700PXH) generate a legacy INTx when the IRQ
275 * entry in the chipset's IO-APIC is masked (as, e.g. the RT kernel does
276 * during interrupt handling). When this INTx generation cannot be disabled,
277 * we reroute these interrupts to their legacy equivalent to get rid of
278 * spurious interrupts.
280 static int acpi_reroute_boot_interrupt(struct pci_dev
*dev
,
281 struct acpi_prt_entry
*entry
)
283 if (noioapicquirk
|| noioapicreroute
) {
286 switch (bridge_has_boot_interrupt_variant(dev
->bus
)) {
288 /* no rerouting necessary */
290 case INTEL_IRQ_REROUTE_VARIANT
:
292 * Remap according to INTx routing table in 6700PXH
293 * specs, intel order number 302628-002, section
294 * 2.15.2. Other chipsets (80332, ...) have the same
295 * mapping and are handled here as well.
297 dev_info(&dev
->dev
, "PCI IRQ %d -> rerouted to legacy "
298 "IRQ %d\n", entry
->index
,
299 (entry
->index
% 4) + 16);
300 entry
->index
= (entry
->index
% 4) + 16;
303 dev_warn(&dev
->dev
, "Cannot reroute IRQ %d to legacy "
304 "IRQ: unknown mapping\n", entry
->index
);
309 #endif /* CONFIG_X86_IO_APIC */
311 static struct acpi_prt_entry
*acpi_pci_irq_lookup(struct pci_dev
*dev
, int pin
)
313 struct acpi_prt_entry
*entry
= NULL
;
314 struct pci_dev
*bridge
;
315 u8 bridge_pin
, orig_pin
= pin
;
318 ret
= acpi_pci_irq_find_prt_entry(dev
, pin
, &entry
);
320 #ifdef CONFIG_X86_IO_APIC
321 acpi_reroute_boot_interrupt(dev
, entry
);
322 #endif /* CONFIG_X86_IO_APIC */
323 ACPI_DEBUG_PRINT((ACPI_DB_INFO
, "Found %s[%c] _PRT entry\n",
324 pci_name(dev
), pin_name(pin
)));
329 * Attempt to derive an IRQ for this device from a parent bridge's
330 * PCI interrupt routing entry (eg. yenta bridge and add-in card bridge).
332 bridge
= dev
->bus
->self
;
334 pin
= pci_swizzle_interrupt_pin(dev
, pin
);
336 if ((bridge
->class >> 8) == PCI_CLASS_BRIDGE_CARDBUS
) {
337 /* PC card has the same IRQ as its cardbridge */
338 bridge_pin
= bridge
->pin
;
340 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
341 "No interrupt pin configured for device %s\n",
348 ret
= acpi_pci_irq_find_prt_entry(bridge
, pin
, &entry
);
350 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
351 "Derived GSI for %s INT %c from %s\n",
352 pci_name(dev
), pin_name(orig_pin
),
358 bridge
= dev
->bus
->self
;
361 dev_warn(&dev
->dev
, "can't derive routing for PCI INT %c\n",
366 #if IS_ENABLED(CONFIG_ISA) || IS_ENABLED(CONFIG_EISA)
367 static int acpi_isa_register_gsi(struct pci_dev
*dev
)
371 /* Interrupt Line values above 0xF are forbidden */
372 if (dev
->irq
> 0 && (dev
->irq
<= 0xF) &&
373 acpi_isa_irq_available(dev
->irq
) &&
374 (acpi_isa_irq_to_gsi(dev
->irq
, &dev_gsi
) == 0)) {
375 dev_warn(&dev
->dev
, "PCI INT %c: no GSI - using ISA IRQ %d\n",
376 pin_name(dev
->pin
), dev
->irq
);
377 acpi_register_gsi(&dev
->dev
, dev_gsi
,
378 ACPI_LEVEL_SENSITIVE
,
385 static inline int acpi_isa_register_gsi(struct pci_dev
*dev
)
391 static inline bool acpi_pci_irq_valid(struct pci_dev
*dev
, u8 pin
)
395 * On x86 irq line 0xff means "unknown" or "no connection"
396 * (PCI 3.0, Section 6.2.4, footnote on page 223).
398 if (dev
->irq
== 0xff) {
399 dev
->irq
= IRQ_NOTCONNECTED
;
400 dev_warn(&dev
->dev
, "PCI INT %c: not connected\n",
408 int acpi_pci_irq_enable(struct pci_dev
*dev
)
410 struct acpi_prt_entry
*entry
;
413 int triggering
= ACPI_LEVEL_SENSITIVE
;
415 * On ARM systems with the GIC interrupt model, level interrupts
416 * are always polarity high by specification; PCI legacy
417 * IRQs lines are inverted before reaching the interrupt
418 * controller and must therefore be considered active high
421 int polarity
= acpi_irq_model
== ACPI_IRQ_MODEL_GIC
?
422 ACPI_ACTIVE_HIGH
: ACPI_ACTIVE_LOW
;
429 ACPI_DEBUG_PRINT((ACPI_DB_INFO
,
430 "No interrupt pin configured for device %s\n",
435 if (dev
->irq_managed
&& dev
->irq
> 0)
438 entry
= acpi_pci_irq_lookup(dev
, pin
);
441 * IDE legacy mode controller IRQs are magic. Why do compat
442 * extensions always make such a nasty mess.
444 if (dev
->class >> 8 == PCI_CLASS_STORAGE_IDE
&&
445 (dev
->class & 0x05) == 0)
451 gsi
= acpi_pci_link_allocate_irq(entry
->link
,
453 &triggering
, &polarity
,
462 * No IRQ known to the ACPI subsystem - maybe the BIOS /
463 * driver reported one, then use it. Exit in any case.
465 if (!acpi_pci_irq_valid(dev
, pin
))
468 if (acpi_isa_register_gsi(dev
))
469 dev_warn(&dev
->dev
, "PCI INT %c: no GSI\n",
476 rc
= acpi_register_gsi(&dev
->dev
, gsi
, triggering
, polarity
);
478 dev_warn(&dev
->dev
, "PCI INT %c: failed to register GSI\n",
484 dev
->irq_managed
= 1;
487 snprintf(link_desc
, sizeof(link_desc
), " -> Link[%s]", link
);
491 dev_dbg(&dev
->dev
, "PCI INT %c%s -> GSI %u (%s, %s) -> IRQ %d\n",
492 pin_name(pin
), link_desc
, gsi
,
493 (triggering
== ACPI_LEVEL_SENSITIVE
) ? "level" : "edge",
494 (polarity
== ACPI_ACTIVE_LOW
) ? "low" : "high", dev
->irq
);
500 void acpi_pci_irq_disable(struct pci_dev
*dev
)
502 struct acpi_prt_entry
*entry
;
507 if (!pin
|| !dev
->irq_managed
|| dev
->irq
<= 0)
510 /* Keep IOAPIC pin configuration when suspending */
511 if (dev
->dev
.power
.is_prepared
)
514 if (dev
->dev
.power
.runtime_status
== RPM_SUSPENDING
)
518 entry
= acpi_pci_irq_lookup(dev
, pin
);
523 gsi
= acpi_pci_link_free_irq(entry
->link
);
530 * TBD: It might be worth clearing dev->irq by magic constant
531 * (e.g. PCI_UNDEFINED_IRQ).
534 dev_dbg(&dev
->dev
, "PCI INT %c disabled\n", pin_name(pin
));
536 acpi_unregister_gsi(gsi
);
537 dev
->irq_managed
= 0;