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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * pci_irq.c - ACPI PCI Interrupt Routing ($Revision: 11 $)
4 *
5 * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
6 * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
7 * Copyright (C) 2002 Dominik Brodowski <devel@brodo.de>
8 * (c) Copyright 2008 Hewlett-Packard Development Company, L.P.
9 * Bjorn Helgaas <bjorn.helgaas@hp.com>
10 */
11
12#define pr_fmt(fmt) "ACPI: PCI: " fmt
13
14#include <linux/dmi.h>
15#include <linux/kernel.h>
16#include <linux/module.h>
17#include <linux/init.h>
18#include <linux/types.h>
19#include <linux/spinlock.h>
20#include <linux/pm.h>
21#include <linux/pci.h>
22#include <linux/acpi.h>
23#include <linux/slab.h>
24#include <linux/interrupt.h>
25
26struct acpi_prt_entry {
27 struct acpi_pci_id id;
28 u8 pin;
29 acpi_handle link;
30 u32 index; /* GSI, or link _CRS index */
31};
32
33static inline char pin_name(int pin)
34{
35 return 'A' + pin - 1;
36}
37
38/* --------------------------------------------------------------------------
39 PCI IRQ Routing Table (PRT) Support
40 -------------------------------------------------------------------------- */
41
42/* http://bugzilla.kernel.org/show_bug.cgi?id=4773 */
43static const struct dmi_system_id medion_md9580[] = {
44 {
45 .ident = "Medion MD9580-F laptop",
46 .matches = {
47 DMI_MATCH(DMI_SYS_VENDOR, "MEDIONNB"),
48 DMI_MATCH(DMI_PRODUCT_NAME, "A555"),
49 },
50 },
51 { }
52};
53
54/* http://bugzilla.kernel.org/show_bug.cgi?id=5044 */
55static const struct dmi_system_id dell_optiplex[] = {
56 {
57 .ident = "Dell Optiplex GX1",
58 .matches = {
59 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
60 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex GX1 600S+"),
61 },
62 },
63 { }
64};
65
66/* http://bugzilla.kernel.org/show_bug.cgi?id=10138 */
67static const struct dmi_system_id hp_t5710[] = {
68 {
69 .ident = "HP t5710",
70 .matches = {
71 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
72 DMI_MATCH(DMI_PRODUCT_NAME, "hp t5000 series"),
73 DMI_MATCH(DMI_BOARD_NAME, "098Ch"),
74 },
75 },
76 { }
77};
78
79struct prt_quirk {
80 const struct dmi_system_id *system;
81 unsigned int segment;
82 unsigned int bus;
83 unsigned int device;
84 unsigned char pin;
85 const char *source; /* according to BIOS */
86 const char *actual_source;
87};
88
89#define PCI_INTX_PIN(c) (c - 'A' + 1)
90
91/*
92 * These systems have incorrect _PRT entries. The BIOS claims the PCI
93 * interrupt at the listed segment/bus/device/pin is connected to the first
94 * link device, but it is actually connected to the second.
95 */
96static const struct prt_quirk prt_quirks[] = {
97 { medion_md9580, 0, 0, 9, PCI_INTX_PIN('A'),
98 "\\_SB_.PCI0.ISA_.LNKA",
99 "\\_SB_.PCI0.ISA_.LNKB"},
100 { dell_optiplex, 0, 0, 0xd, PCI_INTX_PIN('A'),
101 "\\_SB_.LNKB",
102 "\\_SB_.LNKA"},
103 { hp_t5710, 0, 0, 1, PCI_INTX_PIN('A'),
104 "\\_SB_.PCI0.LNK1",
105 "\\_SB_.PCI0.LNK3"},
106};
107
108static void do_prt_fixups(struct acpi_prt_entry *entry,
109 struct acpi_pci_routing_table *prt)
110{
111 int i;
112 const struct prt_quirk *quirk;
113
114 for (i = 0; i < ARRAY_SIZE(prt_quirks); i++) {
115 quirk = &prt_quirks[i];
116
117 /* All current quirks involve link devices, not GSIs */
118 if (dmi_check_system(quirk->system) &&
119 entry->id.segment == quirk->segment &&
120 entry->id.bus == quirk->bus &&
121 entry->id.device == quirk->device &&
122 entry->pin == quirk->pin &&
123 !strcmp(prt->source, quirk->source) &&
124 strlen(prt->source) >= strlen(quirk->actual_source)) {
125 pr_warn("Firmware reports "
126 "%04x:%02x:%02x PCI INT %c connected to %s; "
127 "changing to %s\n",
128 entry->id.segment, entry->id.bus,
129 entry->id.device, pin_name(entry->pin),
130 prt->source, quirk->actual_source);
131 strcpy(prt->source, quirk->actual_source);
132 }
133 }
134}
135
136static int acpi_pci_irq_check_entry(acpi_handle handle, struct pci_dev *dev,
137 int pin, struct acpi_pci_routing_table *prt,
138 struct acpi_prt_entry **entry_ptr)
139{
140 int segment = pci_domain_nr(dev->bus);
141 int bus = dev->bus->number;
142 int device = pci_ari_enabled(dev->bus) ? 0 : PCI_SLOT(dev->devfn);
143 struct acpi_prt_entry *entry;
144
145 if (((prt->address >> 16) & 0xffff) != device ||
146 prt->pin + 1 != pin)
147 return -ENODEV;
148
149 entry = kzalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL);
150 if (!entry)
151 return -ENOMEM;
152
153 /*
154 * Note that the _PRT uses 0=INTA, 1=INTB, etc, while PCI uses
155 * 1=INTA, 2=INTB. We use the PCI encoding throughout, so convert
156 * it here.
157 */
158 entry->id.segment = segment;
159 entry->id.bus = bus;
160 entry->id.device = (prt->address >> 16) & 0xFFFF;
161 entry->pin = prt->pin + 1;
162
163 do_prt_fixups(entry, prt);
164
165 entry->index = prt->source_index;
166
167 /*
168 * Type 1: Dynamic
169 * ---------------
170 * The 'source' field specifies the PCI interrupt link device used to
171 * configure the IRQ assigned to this slot|dev|pin. The 'source_index'
172 * indicates which resource descriptor in the resource template (of
173 * the link device) this interrupt is allocated from.
174 *
175 * NOTE: Don't query the Link Device for IRQ information at this time
176 * because Link Device enumeration may not have occurred yet
177 * (e.g. exists somewhere 'below' this _PRT entry in the ACPI
178 * namespace).
179 */
180 if (prt->source[0])
181 acpi_get_handle(handle, prt->source, &entry->link);
182
183 /*
184 * Type 2: Static
185 * --------------
186 * The 'source' field is NULL, and the 'source_index' field specifies
187 * the IRQ value, which is hardwired to specific interrupt inputs on
188 * the interrupt controller.
189 */
190 pr_debug("%04x:%02x:%02x[%c] -> %s[%d]\n",
191 entry->id.segment, entry->id.bus, entry->id.device,
192 pin_name(entry->pin), prt->source, entry->index);
193
194 *entry_ptr = entry;
195
196 return 0;
197}
198
199static int acpi_pci_irq_find_prt_entry(struct pci_dev *dev,
200 int pin, struct acpi_prt_entry **entry_ptr)
201{
202 acpi_status status;
203 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
204 struct acpi_pci_routing_table *entry;
205 acpi_handle handle = NULL;
206
207 if (dev->bus->bridge)
208 handle = ACPI_HANDLE(dev->bus->bridge);
209
210 if (!handle)
211 return -ENODEV;
212
213 /* 'handle' is the _PRT's parent (root bridge or PCI-PCI bridge) */
214 status = acpi_get_irq_routing_table(handle, &buffer);
215 if (ACPI_FAILURE(status)) {
216 kfree(buffer.pointer);
217 return -ENODEV;
218 }
219
220 entry = buffer.pointer;
221 while (entry && (entry->length > 0)) {
222 if (!acpi_pci_irq_check_entry(handle, dev, pin,
223 entry, entry_ptr))
224 break;
225 entry = (struct acpi_pci_routing_table *)
226 ((unsigned long)entry + entry->length);
227 }
228
229 kfree(buffer.pointer);
230 return 0;
231}
232
233/* --------------------------------------------------------------------------
234 PCI Interrupt Routing Support
235 -------------------------------------------------------------------------- */
236#ifdef CONFIG_X86_IO_APIC
237extern int noioapicquirk;
238extern int noioapicreroute;
239
240static int bridge_has_boot_interrupt_variant(struct pci_bus *bus)
241{
242 struct pci_bus *bus_it;
243
244 for (bus_it = bus ; bus_it ; bus_it = bus_it->parent) {
245 if (!bus_it->self)
246 return 0;
247 if (bus_it->self->irq_reroute_variant)
248 return bus_it->self->irq_reroute_variant;
249 }
250 return 0;
251}
252
253/*
254 * Some chipsets (e.g. Intel 6700PXH) generate a legacy INTx when the IRQ
255 * entry in the chipset's IO-APIC is masked (as, e.g. the RT kernel does
256 * during interrupt handling). When this INTx generation cannot be disabled,
257 * we reroute these interrupts to their legacy equivalent to get rid of
258 * spurious interrupts.
259 */
260static int acpi_reroute_boot_interrupt(struct pci_dev *dev,
261 struct acpi_prt_entry *entry)
262{
263 if (noioapicquirk || noioapicreroute) {
264 return 0;
265 } else {
266 switch (bridge_has_boot_interrupt_variant(dev->bus)) {
267 case 0:
268 /* no rerouting necessary */
269 return 0;
270 case INTEL_IRQ_REROUTE_VARIANT:
271 /*
272 * Remap according to INTx routing table in 6700PXH
273 * specs, intel order number 302628-002, section
274 * 2.15.2. Other chipsets (80332, ...) have the same
275 * mapping and are handled here as well.
276 */
277 dev_info(&dev->dev, "PCI IRQ %d -> rerouted to legacy "
278 "IRQ %d\n", entry->index,
279 (entry->index % 4) + 16);
280 entry->index = (entry->index % 4) + 16;
281 return 1;
282 default:
283 dev_warn(&dev->dev, "Cannot reroute IRQ %d to legacy "
284 "IRQ: unknown mapping\n", entry->index);
285 return -1;
286 }
287 }
288}
289#endif /* CONFIG_X86_IO_APIC */
290
291struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin)
292{
293 struct acpi_prt_entry *entry = NULL;
294 struct pci_dev *bridge;
295 u8 bridge_pin, orig_pin = pin;
296 int ret;
297
298 ret = acpi_pci_irq_find_prt_entry(dev, pin, &entry);
299 if (!ret && entry) {
300#ifdef CONFIG_X86_IO_APIC
301 acpi_reroute_boot_interrupt(dev, entry);
302#endif /* CONFIG_X86_IO_APIC */
303 dev_dbg(&dev->dev, "Found [%c] _PRT entry\n", pin_name(pin));
304 return entry;
305 }
306
307 /*
308 * Attempt to derive an IRQ for this device from a parent bridge's
309 * PCI interrupt routing entry (eg. yenta bridge and add-in card bridge).
310 */
311 bridge = dev->bus->self;
312 while (bridge) {
313 pin = pci_swizzle_interrupt_pin(dev, pin);
314
315 if ((bridge->class >> 8) == PCI_CLASS_BRIDGE_CARDBUS) {
316 /* PC card has the same IRQ as its cardbridge */
317 bridge_pin = bridge->pin;
318 if (!bridge_pin) {
319 dev_dbg(&bridge->dev, "No interrupt pin configured\n");
320 return NULL;
321 }
322 pin = bridge_pin;
323 }
324
325 ret = acpi_pci_irq_find_prt_entry(bridge, pin, &entry);
326 if (!ret && entry) {
327 dev_dbg(&dev->dev, "Derived GSI INT %c from %s\n",
328 pin_name(orig_pin), pci_name(bridge));
329 return entry;
330 }
331
332 dev = bridge;
333 bridge = dev->bus->self;
334 }
335
336 dev_warn(&dev->dev, "can't derive routing for PCI INT %c\n",
337 pin_name(orig_pin));
338 return NULL;
339}
340
341#if IS_ENABLED(CONFIG_ISA) || IS_ENABLED(CONFIG_EISA)
342static int acpi_isa_register_gsi(struct pci_dev *dev)
343{
344 u32 dev_gsi;
345
346 /* Interrupt Line values above 0xF are forbidden */
347 if (dev->irq > 0 && (dev->irq <= 0xF) &&
348 acpi_isa_irq_available(dev->irq) &&
349 (acpi_isa_irq_to_gsi(dev->irq, &dev_gsi) == 0)) {
350 dev_warn(&dev->dev, "PCI INT %c: no GSI - using ISA IRQ %d\n",
351 pin_name(dev->pin), dev->irq);
352 acpi_register_gsi(&dev->dev, dev_gsi,
353 ACPI_LEVEL_SENSITIVE,
354 ACPI_ACTIVE_LOW);
355 return 0;
356 }
357 return -EINVAL;
358}
359#else
360static inline int acpi_isa_register_gsi(struct pci_dev *dev)
361{
362 return -ENODEV;
363}
364#endif
365
366static inline bool acpi_pci_irq_valid(struct pci_dev *dev, u8 pin)
367{
368#ifdef CONFIG_X86
369 /*
370 * On x86 irq line 0xff means "unknown" or "no connection"
371 * (PCI 3.0, Section 6.2.4, footnote on page 223).
372 */
373 if (dev->irq == 0xff) {
374 dev->irq = IRQ_NOTCONNECTED;
375 dev_warn(&dev->dev, "PCI INT %c: not connected\n",
376 pin_name(pin));
377 return false;
378 }
379#endif
380 return true;
381}
382
383int acpi_pci_irq_enable(struct pci_dev *dev)
384{
385 struct acpi_prt_entry *entry;
386 int gsi;
387 u8 pin;
388 int triggering = ACPI_LEVEL_SENSITIVE;
389 /*
390 * On ARM systems with the GIC interrupt model, or LoongArch
391 * systems with the LPIC interrupt model, level interrupts
392 * are always polarity high by specification; PCI legacy
393 * IRQs lines are inverted before reaching the interrupt
394 * controller and must therefore be considered active high
395 * as default.
396 */
397 int polarity = acpi_irq_model == ACPI_IRQ_MODEL_GIC ||
398 acpi_irq_model == ACPI_IRQ_MODEL_LPIC ?
399 ACPI_ACTIVE_HIGH : ACPI_ACTIVE_LOW;
400 char *link = NULL;
401 char link_desc[16];
402 int rc;
403
404 pin = dev->pin;
405 if (!pin) {
406 dev_dbg(&dev->dev, "No interrupt pin configured\n");
407 return 0;
408 }
409
410 if (dev->irq_managed && dev->irq > 0)
411 return 0;
412
413 entry = acpi_pci_irq_lookup(dev, pin);
414 if (!entry) {
415 /*
416 * IDE legacy mode controller IRQs are magic. Why do compat
417 * extensions always make such a nasty mess.
418 */
419 if (dev->class >> 8 == PCI_CLASS_STORAGE_IDE &&
420 (dev->class & 0x05) == 0)
421 return 0;
422 }
423
424 if (entry) {
425 if (entry->link)
426 gsi = acpi_pci_link_allocate_irq(entry->link,
427 entry->index,
428 &triggering, &polarity,
429 &link);
430 else
431 gsi = entry->index;
432 } else
433 gsi = -1;
434
435 if (gsi < 0) {
436 /*
437 * No IRQ known to the ACPI subsystem - maybe the BIOS /
438 * driver reported one, then use it. Exit in any case.
439 */
440 if (!acpi_pci_irq_valid(dev, pin)) {
441 kfree(entry);
442 return 0;
443 }
444
445 if (acpi_isa_register_gsi(dev))
446 dev_warn(&dev->dev, "PCI INT %c: no GSI\n",
447 pin_name(pin));
448
449 kfree(entry);
450 return 0;
451 }
452
453 rc = acpi_register_gsi(&dev->dev, gsi, triggering, polarity);
454 if (rc < 0) {
455 dev_warn(&dev->dev, "PCI INT %c: failed to register GSI\n",
456 pin_name(pin));
457 kfree(entry);
458 return rc;
459 }
460 dev->irq = rc;
461 dev->irq_managed = 1;
462
463 if (link)
464 snprintf(link_desc, sizeof(link_desc), " -> Link[%s]", link);
465 else
466 link_desc[0] = '\0';
467
468 dev_dbg(&dev->dev, "PCI INT %c%s -> GSI %u (%s, %s) -> IRQ %d\n",
469 pin_name(pin), link_desc, gsi,
470 (triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge",
471 (polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq);
472
473 kfree(entry);
474 return 0;
475}
476
477void acpi_pci_irq_disable(struct pci_dev *dev)
478{
479 struct acpi_prt_entry *entry;
480 int gsi;
481 u8 pin;
482
483 pin = dev->pin;
484 if (!pin || !dev->irq_managed || dev->irq <= 0)
485 return;
486
487 /* Keep IOAPIC pin configuration when suspending */
488 if (dev->dev.power.is_prepared)
489 return;
490#ifdef CONFIG_PM
491 if (dev->dev.power.runtime_status == RPM_SUSPENDING)
492 return;
493#endif
494
495 entry = acpi_pci_irq_lookup(dev, pin);
496 if (!entry)
497 return;
498
499 if (entry->link)
500 gsi = acpi_pci_link_free_irq(entry->link);
501 else
502 gsi = entry->index;
503
504 kfree(entry);
505
506 /*
507 * TBD: It might be worth clearing dev->irq by magic constant
508 * (e.g. PCI_UNDEFINED_IRQ).
509 */
510
511 dev_dbg(&dev->dev, "PCI INT %c disabled\n", pin_name(pin));
512 if (gsi >= 0) {
513 acpi_unregister_gsi(gsi);
514 dev->irq_managed = 0;
515 }
516}
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 * (c) Copyright 2008 Hewlett-Packard Development Company, L.P.
8 * Bjorn Helgaas <bjorn.helgaas@hp.com>
9 *
10 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
11 *
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.
16 *
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.
21 *
22 * You should have received a copy of the GNU General Public License along
23 * with this program; if not, write to the Free Software Foundation, Inc.,
24 * 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
25 *
26 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
27 */
28
29
30#include <linux/dmi.h>
31#include <linux/kernel.h>
32#include <linux/module.h>
33#include <linux/init.h>
34#include <linux/types.h>
35#include <linux/spinlock.h>
36#include <linux/pm.h>
37#include <linux/pci.h>
38#include <linux/acpi.h>
39#include <linux/slab.h>
40
41#define PREFIX "ACPI: "
42
43#define _COMPONENT ACPI_PCI_COMPONENT
44ACPI_MODULE_NAME("pci_irq");
45
46struct acpi_prt_entry {
47 struct list_head list;
48 struct acpi_pci_id id;
49 u8 pin;
50 acpi_handle link;
51 u32 index; /* GSI, or link _CRS index */
52};
53
54static inline char pin_name(int pin)
55{
56 return 'A' + pin - 1;
57}
58
59/* --------------------------------------------------------------------------
60 PCI IRQ Routing Table (PRT) Support
61 -------------------------------------------------------------------------- */
62
63/* http://bugzilla.kernel.org/show_bug.cgi?id=4773 */
64static const struct dmi_system_id medion_md9580[] = {
65 {
66 .ident = "Medion MD9580-F laptop",
67 .matches = {
68 DMI_MATCH(DMI_SYS_VENDOR, "MEDIONNB"),
69 DMI_MATCH(DMI_PRODUCT_NAME, "A555"),
70 },
71 },
72 { }
73};
74
75/* http://bugzilla.kernel.org/show_bug.cgi?id=5044 */
76static const struct dmi_system_id dell_optiplex[] = {
77 {
78 .ident = "Dell Optiplex GX1",
79 .matches = {
80 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
81 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex GX1 600S+"),
82 },
83 },
84 { }
85};
86
87/* http://bugzilla.kernel.org/show_bug.cgi?id=10138 */
88static const struct dmi_system_id hp_t5710[] = {
89 {
90 .ident = "HP t5710",
91 .matches = {
92 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
93 DMI_MATCH(DMI_PRODUCT_NAME, "hp t5000 series"),
94 DMI_MATCH(DMI_BOARD_NAME, "098Ch"),
95 },
96 },
97 { }
98};
99
100struct prt_quirk {
101 const struct dmi_system_id *system;
102 unsigned int segment;
103 unsigned int bus;
104 unsigned int device;
105 unsigned char pin;
106 const char *source; /* according to BIOS */
107 const char *actual_source;
108};
109
110#define PCI_INTX_PIN(c) (c - 'A' + 1)
111
112/*
113 * These systems have incorrect _PRT entries. The BIOS claims the PCI
114 * interrupt at the listed segment/bus/device/pin is connected to the first
115 * link device, but it is actually connected to the second.
116 */
117static const struct prt_quirk prt_quirks[] = {
118 { medion_md9580, 0, 0, 9, PCI_INTX_PIN('A'),
119 "\\_SB_.PCI0.ISA_.LNKA",
120 "\\_SB_.PCI0.ISA_.LNKB"},
121 { dell_optiplex, 0, 0, 0xd, PCI_INTX_PIN('A'),
122 "\\_SB_.LNKB",
123 "\\_SB_.LNKA"},
124 { hp_t5710, 0, 0, 1, PCI_INTX_PIN('A'),
125 "\\_SB_.PCI0.LNK1",
126 "\\_SB_.PCI0.LNK3"},
127};
128
129static void do_prt_fixups(struct acpi_prt_entry *entry,
130 struct acpi_pci_routing_table *prt)
131{
132 int i;
133 const struct prt_quirk *quirk;
134
135 for (i = 0; i < ARRAY_SIZE(prt_quirks); i++) {
136 quirk = &prt_quirks[i];
137
138 /* All current quirks involve link devices, not GSIs */
139 if (!prt->source)
140 continue;
141
142 if (dmi_check_system(quirk->system) &&
143 entry->id.segment == quirk->segment &&
144 entry->id.bus == quirk->bus &&
145 entry->id.device == quirk->device &&
146 entry->pin == quirk->pin &&
147 !strcmp(prt->source, quirk->source) &&
148 strlen(prt->source) >= strlen(quirk->actual_source)) {
149 printk(KERN_WARNING PREFIX "firmware reports "
150 "%04x:%02x:%02x PCI INT %c connected to %s; "
151 "changing to %s\n",
152 entry->id.segment, entry->id.bus,
153 entry->id.device, pin_name(entry->pin),
154 prt->source, quirk->actual_source);
155 strcpy(prt->source, quirk->actual_source);
156 }
157 }
158}
159
160static int acpi_pci_irq_check_entry(acpi_handle handle, struct pci_dev *dev,
161 int pin, struct acpi_pci_routing_table *prt,
162 struct acpi_prt_entry **entry_ptr)
163{
164 int segment = pci_domain_nr(dev->bus);
165 int bus = dev->bus->number;
166 int device = PCI_SLOT(dev->devfn);
167 struct acpi_prt_entry *entry;
168
169 if (((prt->address >> 16) & 0xffff) != device ||
170 prt->pin + 1 != pin)
171 return -ENODEV;
172
173 entry = kzalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL);
174 if (!entry)
175 return -ENOMEM;
176
177 /*
178 * Note that the _PRT uses 0=INTA, 1=INTB, etc, while PCI uses
179 * 1=INTA, 2=INTB. We use the PCI encoding throughout, so convert
180 * it here.
181 */
182 entry->id.segment = segment;
183 entry->id.bus = bus;
184 entry->id.device = (prt->address >> 16) & 0xFFFF;
185 entry->pin = prt->pin + 1;
186
187 do_prt_fixups(entry, prt);
188
189 entry->index = prt->source_index;
190
191 /*
192 * Type 1: Dynamic
193 * ---------------
194 * The 'source' field specifies the PCI interrupt link device used to
195 * configure the IRQ assigned to this slot|dev|pin. The 'source_index'
196 * indicates which resource descriptor in the resource template (of
197 * the link device) this interrupt is allocated from.
198 *
199 * NOTE: Don't query the Link Device for IRQ information at this time
200 * because Link Device enumeration may not have occurred yet
201 * (e.g. exists somewhere 'below' this _PRT entry in the ACPI
202 * namespace).
203 */
204 if (prt->source[0])
205 acpi_get_handle(handle, prt->source, &entry->link);
206
207 /*
208 * Type 2: Static
209 * --------------
210 * The 'source' field is NULL, and the 'source_index' field specifies
211 * the IRQ value, which is hardwired to specific interrupt inputs on
212 * the interrupt controller.
213 */
214
215 ACPI_DEBUG_PRINT_RAW((ACPI_DB_INFO,
216 " %04x:%02x:%02x[%c] -> %s[%d]\n",
217 entry->id.segment, entry->id.bus,
218 entry->id.device, pin_name(entry->pin),
219 prt->source, entry->index));
220
221 *entry_ptr = entry;
222
223 return 0;
224}
225
226static int acpi_pci_irq_find_prt_entry(struct pci_dev *dev,
227 int pin, struct acpi_prt_entry **entry_ptr)
228{
229 acpi_status status;
230 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
231 struct acpi_pci_routing_table *entry;
232 acpi_handle handle = NULL;
233
234 if (dev->bus->bridge)
235 handle = ACPI_HANDLE(dev->bus->bridge);
236
237 if (!handle)
238 return -ENODEV;
239
240 /* 'handle' is the _PRT's parent (root bridge or PCI-PCI bridge) */
241 status = acpi_get_irq_routing_table(handle, &buffer);
242 if (ACPI_FAILURE(status)) {
243 kfree(buffer.pointer);
244 return -ENODEV;
245 }
246
247 entry = buffer.pointer;
248 while (entry && (entry->length > 0)) {
249 if (!acpi_pci_irq_check_entry(handle, dev, pin,
250 entry, entry_ptr))
251 break;
252 entry = (struct acpi_pci_routing_table *)
253 ((unsigned long)entry + entry->length);
254 }
255
256 kfree(buffer.pointer);
257 return 0;
258}
259
260/* --------------------------------------------------------------------------
261 PCI Interrupt Routing Support
262 -------------------------------------------------------------------------- */
263#ifdef CONFIG_X86_IO_APIC
264extern int noioapicquirk;
265extern int noioapicreroute;
266
267static int bridge_has_boot_interrupt_variant(struct pci_bus *bus)
268{
269 struct pci_bus *bus_it;
270
271 for (bus_it = bus ; bus_it ; bus_it = bus_it->parent) {
272 if (!bus_it->self)
273 return 0;
274 if (bus_it->self->irq_reroute_variant)
275 return bus_it->self->irq_reroute_variant;
276 }
277 return 0;
278}
279
280/*
281 * Some chipsets (e.g. Intel 6700PXH) generate a legacy INTx when the IRQ
282 * entry in the chipset's IO-APIC is masked (as, e.g. the RT kernel does
283 * during interrupt handling). When this INTx generation cannot be disabled,
284 * we reroute these interrupts to their legacy equivalent to get rid of
285 * spurious interrupts.
286 */
287static int acpi_reroute_boot_interrupt(struct pci_dev *dev,
288 struct acpi_prt_entry *entry)
289{
290 if (noioapicquirk || noioapicreroute) {
291 return 0;
292 } else {
293 switch (bridge_has_boot_interrupt_variant(dev->bus)) {
294 case 0:
295 /* no rerouting necessary */
296 return 0;
297 case INTEL_IRQ_REROUTE_VARIANT:
298 /*
299 * Remap according to INTx routing table in 6700PXH
300 * specs, intel order number 302628-002, section
301 * 2.15.2. Other chipsets (80332, ...) have the same
302 * mapping and are handled here as well.
303 */
304 dev_info(&dev->dev, "PCI IRQ %d -> rerouted to legacy "
305 "IRQ %d\n", entry->index,
306 (entry->index % 4) + 16);
307 entry->index = (entry->index % 4) + 16;
308 return 1;
309 default:
310 dev_warn(&dev->dev, "Cannot reroute IRQ %d to legacy "
311 "IRQ: unknown mapping\n", entry->index);
312 return -1;
313 }
314 }
315}
316#endif /* CONFIG_X86_IO_APIC */
317
318static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin)
319{
320 struct acpi_prt_entry *entry = NULL;
321 struct pci_dev *bridge;
322 u8 bridge_pin, orig_pin = pin;
323 int ret;
324
325 ret = acpi_pci_irq_find_prt_entry(dev, pin, &entry);
326 if (!ret && entry) {
327#ifdef CONFIG_X86_IO_APIC
328 acpi_reroute_boot_interrupt(dev, entry);
329#endif /* CONFIG_X86_IO_APIC */
330 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %s[%c] _PRT entry\n",
331 pci_name(dev), pin_name(pin)));
332 return entry;
333 }
334
335 /*
336 * Attempt to derive an IRQ for this device from a parent bridge's
337 * PCI interrupt routing entry (eg. yenta bridge and add-in card bridge).
338 */
339 bridge = dev->bus->self;
340 while (bridge) {
341 pin = pci_swizzle_interrupt_pin(dev, pin);
342
343 if ((bridge->class >> 8) == PCI_CLASS_BRIDGE_CARDBUS) {
344 /* PC card has the same IRQ as its cardbridge */
345 bridge_pin = bridge->pin;
346 if (!bridge_pin) {
347 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
348 "No interrupt pin configured for device %s\n",
349 pci_name(bridge)));
350 return NULL;
351 }
352 pin = bridge_pin;
353 }
354
355 ret = acpi_pci_irq_find_prt_entry(bridge, pin, &entry);
356 if (!ret && entry) {
357 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
358 "Derived GSI for %s INT %c from %s\n",
359 pci_name(dev), pin_name(orig_pin),
360 pci_name(bridge)));
361 return entry;
362 }
363
364 dev = bridge;
365 bridge = dev->bus->self;
366 }
367
368 dev_warn(&dev->dev, "can't derive routing for PCI INT %c\n",
369 pin_name(orig_pin));
370 return NULL;
371}
372
373#if IS_ENABLED(CONFIG_ISA) || IS_ENABLED(CONFIG_EISA)
374static int acpi_isa_register_gsi(struct pci_dev *dev)
375{
376 u32 dev_gsi;
377
378 /* Interrupt Line values above 0xF are forbidden */
379 if (dev->irq > 0 && (dev->irq <= 0xF) &&
380 (acpi_isa_irq_to_gsi(dev->irq, &dev_gsi) == 0)) {
381 dev_warn(&dev->dev, "PCI INT %c: no GSI - using ISA IRQ %d\n",
382 pin_name(dev->pin), dev->irq);
383 acpi_register_gsi(&dev->dev, dev_gsi,
384 ACPI_LEVEL_SENSITIVE,
385 ACPI_ACTIVE_LOW);
386 return 0;
387 }
388 return -EINVAL;
389}
390#else
391static inline int acpi_isa_register_gsi(struct pci_dev *dev)
392{
393 return -ENODEV;
394}
395#endif
396
397int acpi_pci_irq_enable(struct pci_dev *dev)
398{
399 struct acpi_prt_entry *entry;
400 int gsi;
401 u8 pin;
402 int triggering = ACPI_LEVEL_SENSITIVE;
403 int polarity = ACPI_ACTIVE_LOW;
404 char *link = NULL;
405 char link_desc[16];
406 int rc;
407
408 pin = dev->pin;
409 if (!pin) {
410 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
411 "No interrupt pin configured for device %s\n",
412 pci_name(dev)));
413 return 0;
414 }
415
416 entry = acpi_pci_irq_lookup(dev, pin);
417 if (!entry) {
418 /*
419 * IDE legacy mode controller IRQs are magic. Why do compat
420 * extensions always make such a nasty mess.
421 */
422 if (dev->class >> 8 == PCI_CLASS_STORAGE_IDE &&
423 (dev->class & 0x05) == 0)
424 return 0;
425 }
426
427 if (entry) {
428 if (entry->link)
429 gsi = acpi_pci_link_allocate_irq(entry->link,
430 entry->index,
431 &triggering, &polarity,
432 &link);
433 else
434 gsi = entry->index;
435 } else
436 gsi = -1;
437
438 /*
439 * No IRQ known to the ACPI subsystem - maybe the BIOS /
440 * driver reported one, then use it. Exit in any case.
441 */
442 if (gsi < 0) {
443 if (acpi_isa_register_gsi(dev))
444 dev_warn(&dev->dev, "PCI INT %c: no GSI\n",
445 pin_name(pin));
446
447 kfree(entry);
448 return 0;
449 }
450
451 rc = acpi_register_gsi(&dev->dev, gsi, triggering, polarity);
452 if (rc < 0) {
453 dev_warn(&dev->dev, "PCI INT %c: failed to register GSI\n",
454 pin_name(pin));
455 kfree(entry);
456 return rc;
457 }
458 dev->irq = rc;
459
460 if (link)
461 snprintf(link_desc, sizeof(link_desc), " -> Link[%s]", link);
462 else
463 link_desc[0] = '\0';
464
465 dev_dbg(&dev->dev, "PCI INT %c%s -> GSI %u (%s, %s) -> IRQ %d\n",
466 pin_name(pin), link_desc, gsi,
467 (triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge",
468 (polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq);
469
470 kfree(entry);
471 return 0;
472}
473
474void acpi_pci_irq_disable(struct pci_dev *dev)
475{
476 struct acpi_prt_entry *entry;
477 int gsi;
478 u8 pin;
479
480 pin = dev->pin;
481 if (!pin)
482 return;
483
484 entry = acpi_pci_irq_lookup(dev, pin);
485 if (!entry)
486 return;
487
488 if (entry->link)
489 gsi = acpi_pci_link_free_irq(entry->link);
490 else
491 gsi = entry->index;
492
493 kfree(entry);
494
495 /*
496 * TBD: It might be worth clearing dev->irq by magic constant
497 * (e.g. PCI_UNDEFINED_IRQ).
498 */
499
500 dev_dbg(&dev->dev, "PCI INT %c disabled\n", pin_name(pin));
501 acpi_unregister_gsi(gsi);
502}