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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#include <acpi/acpi_bus.h>
41#include <acpi/acpi_drivers.h>
42
43#define PREFIX "ACPI: "
44
45#define _COMPONENT ACPI_PCI_COMPONENT
46ACPI_MODULE_NAME("pci_irq");
47
48struct acpi_prt_entry {
49 struct list_head list;
50 struct acpi_pci_id id;
51 u8 pin;
52 acpi_handle link;
53 u32 index; /* GSI, or link _CRS index */
54};
55
56static LIST_HEAD(acpi_prt_list);
57static DEFINE_SPINLOCK(acpi_prt_lock);
58
59static inline char pin_name(int pin)
60{
61 return 'A' + pin - 1;
62}
63
64/* --------------------------------------------------------------------------
65 PCI IRQ Routing Table (PRT) Support
66 -------------------------------------------------------------------------- */
67
68static struct acpi_prt_entry *acpi_pci_irq_find_prt_entry(struct pci_dev *dev,
69 int pin)
70{
71 struct acpi_prt_entry *entry;
72 int segment = pci_domain_nr(dev->bus);
73 int bus = dev->bus->number;
74 int device = PCI_SLOT(dev->devfn);
75
76 spin_lock(&acpi_prt_lock);
77 list_for_each_entry(entry, &acpi_prt_list, list) {
78 if ((segment == entry->id.segment)
79 && (bus == entry->id.bus)
80 && (device == entry->id.device)
81 && (pin == entry->pin)) {
82 spin_unlock(&acpi_prt_lock);
83 return entry;
84 }
85 }
86 spin_unlock(&acpi_prt_lock);
87 return NULL;
88}
89
90/* http://bugzilla.kernel.org/show_bug.cgi?id=4773 */
91static const struct dmi_system_id medion_md9580[] = {
92 {
93 .ident = "Medion MD9580-F laptop",
94 .matches = {
95 DMI_MATCH(DMI_SYS_VENDOR, "MEDIONNB"),
96 DMI_MATCH(DMI_PRODUCT_NAME, "A555"),
97 },
98 },
99 { }
100};
101
102/* http://bugzilla.kernel.org/show_bug.cgi?id=5044 */
103static const struct dmi_system_id dell_optiplex[] = {
104 {
105 .ident = "Dell Optiplex GX1",
106 .matches = {
107 DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
108 DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex GX1 600S+"),
109 },
110 },
111 { }
112};
113
114/* http://bugzilla.kernel.org/show_bug.cgi?id=10138 */
115static const struct dmi_system_id hp_t5710[] = {
116 {
117 .ident = "HP t5710",
118 .matches = {
119 DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
120 DMI_MATCH(DMI_PRODUCT_NAME, "hp t5000 series"),
121 DMI_MATCH(DMI_BOARD_NAME, "098Ch"),
122 },
123 },
124 { }
125};
126
127struct prt_quirk {
128 const struct dmi_system_id *system;
129 unsigned int segment;
130 unsigned int bus;
131 unsigned int device;
132 unsigned char pin;
133 const char *source; /* according to BIOS */
134 const char *actual_source;
135};
136
137#define PCI_INTX_PIN(c) (c - 'A' + 1)
138
139/*
140 * These systems have incorrect _PRT entries. The BIOS claims the PCI
141 * interrupt at the listed segment/bus/device/pin is connected to the first
142 * link device, but it is actually connected to the second.
143 */
144static const struct prt_quirk prt_quirks[] = {
145 { medion_md9580, 0, 0, 9, PCI_INTX_PIN('A'),
146 "\\_SB_.PCI0.ISA_.LNKA",
147 "\\_SB_.PCI0.ISA_.LNKB"},
148 { dell_optiplex, 0, 0, 0xd, PCI_INTX_PIN('A'),
149 "\\_SB_.LNKB",
150 "\\_SB_.LNKA"},
151 { hp_t5710, 0, 0, 1, PCI_INTX_PIN('A'),
152 "\\_SB_.PCI0.LNK1",
153 "\\_SB_.PCI0.LNK3"},
154};
155
156static void do_prt_fixups(struct acpi_prt_entry *entry,
157 struct acpi_pci_routing_table *prt)
158{
159 int i;
160 const struct prt_quirk *quirk;
161
162 for (i = 0; i < ARRAY_SIZE(prt_quirks); i++) {
163 quirk = &prt_quirks[i];
164
165 /* All current quirks involve link devices, not GSIs */
166 if (!prt->source)
167 continue;
168
169 if (dmi_check_system(quirk->system) &&
170 entry->id.segment == quirk->segment &&
171 entry->id.bus == quirk->bus &&
172 entry->id.device == quirk->device &&
173 entry->pin == quirk->pin &&
174 !strcmp(prt->source, quirk->source) &&
175 strlen(prt->source) >= strlen(quirk->actual_source)) {
176 printk(KERN_WARNING PREFIX "firmware reports "
177 "%04x:%02x:%02x PCI INT %c connected to %s; "
178 "changing to %s\n",
179 entry->id.segment, entry->id.bus,
180 entry->id.device, pin_name(entry->pin),
181 prt->source, quirk->actual_source);
182 strcpy(prt->source, quirk->actual_source);
183 }
184 }
185}
186
187static int acpi_pci_irq_add_entry(acpi_handle handle, struct pci_bus *bus,
188 struct acpi_pci_routing_table *prt)
189{
190 struct acpi_prt_entry *entry;
191
192 entry = kzalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL);
193 if (!entry)
194 return -ENOMEM;
195
196 /*
197 * Note that the _PRT uses 0=INTA, 1=INTB, etc, while PCI uses
198 * 1=INTA, 2=INTB. We use the PCI encoding throughout, so convert
199 * it here.
200 */
201 entry->id.segment = pci_domain_nr(bus);
202 entry->id.bus = bus->number;
203 entry->id.device = (prt->address >> 16) & 0xFFFF;
204 entry->pin = prt->pin + 1;
205
206 do_prt_fixups(entry, prt);
207
208 entry->index = prt->source_index;
209
210 /*
211 * Type 1: Dynamic
212 * ---------------
213 * The 'source' field specifies the PCI interrupt link device used to
214 * configure the IRQ assigned to this slot|dev|pin. The 'source_index'
215 * indicates which resource descriptor in the resource template (of
216 * the link device) this interrupt is allocated from.
217 *
218 * NOTE: Don't query the Link Device for IRQ information at this time
219 * because Link Device enumeration may not have occurred yet
220 * (e.g. exists somewhere 'below' this _PRT entry in the ACPI
221 * namespace).
222 */
223 if (prt->source[0])
224 acpi_get_handle(handle, prt->source, &entry->link);
225
226 /*
227 * Type 2: Static
228 * --------------
229 * The 'source' field is NULL, and the 'source_index' field specifies
230 * the IRQ value, which is hardwired to specific interrupt inputs on
231 * the interrupt controller.
232 */
233
234 ACPI_DEBUG_PRINT_RAW((ACPI_DB_INFO,
235 " %04x:%02x:%02x[%c] -> %s[%d]\n",
236 entry->id.segment, entry->id.bus,
237 entry->id.device, pin_name(entry->pin),
238 prt->source, entry->index));
239
240 spin_lock(&acpi_prt_lock);
241 list_add_tail(&entry->list, &acpi_prt_list);
242 spin_unlock(&acpi_prt_lock);
243
244 return 0;
245}
246
247int acpi_pci_irq_add_prt(acpi_handle handle, struct pci_bus *bus)
248{
249 acpi_status status;
250 struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
251 struct acpi_pci_routing_table *entry;
252
253 /* 'handle' is the _PRT's parent (root bridge or PCI-PCI bridge) */
254 status = acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
255 if (ACPI_FAILURE(status))
256 return -ENODEV;
257
258 printk(KERN_DEBUG "ACPI: PCI Interrupt Routing Table [%s._PRT]\n",
259 (char *) buffer.pointer);
260
261 kfree(buffer.pointer);
262
263 buffer.length = ACPI_ALLOCATE_BUFFER;
264 buffer.pointer = NULL;
265
266 status = acpi_get_irq_routing_table(handle, &buffer);
267 if (ACPI_FAILURE(status)) {
268 ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRT [%s]",
269 acpi_format_exception(status)));
270 kfree(buffer.pointer);
271 return -ENODEV;
272 }
273
274 entry = buffer.pointer;
275 while (entry && (entry->length > 0)) {
276 acpi_pci_irq_add_entry(handle, bus, entry);
277 entry = (struct acpi_pci_routing_table *)
278 ((unsigned long)entry + entry->length);
279 }
280
281 kfree(buffer.pointer);
282 return 0;
283}
284
285void acpi_pci_irq_del_prt(struct pci_bus *bus)
286{
287 struct acpi_prt_entry *entry, *tmp;
288
289 printk(KERN_DEBUG
290 "ACPI: Delete PCI Interrupt Routing Table for %04x:%02x\n",
291 pci_domain_nr(bus), bus->number);
292 spin_lock(&acpi_prt_lock);
293 list_for_each_entry_safe(entry, tmp, &acpi_prt_list, list) {
294 if (pci_domain_nr(bus) == entry->id.segment
295 && bus->number == entry->id.bus) {
296 list_del(&entry->list);
297 kfree(entry);
298 }
299 }
300 spin_unlock(&acpi_prt_lock);
301}
302
303/* --------------------------------------------------------------------------
304 PCI Interrupt Routing Support
305 -------------------------------------------------------------------------- */
306#ifdef CONFIG_X86_IO_APIC
307extern int noioapicquirk;
308extern int noioapicreroute;
309
310static int bridge_has_boot_interrupt_variant(struct pci_bus *bus)
311{
312 struct pci_bus *bus_it;
313
314 for (bus_it = bus ; bus_it ; bus_it = bus_it->parent) {
315 if (!bus_it->self)
316 return 0;
317 if (bus_it->self->irq_reroute_variant)
318 return bus_it->self->irq_reroute_variant;
319 }
320 return 0;
321}
322
323/*
324 * Some chipsets (e.g. Intel 6700PXH) generate a legacy INTx when the IRQ
325 * entry in the chipset's IO-APIC is masked (as, e.g. the RT kernel does
326 * during interrupt handling). When this INTx generation cannot be disabled,
327 * we reroute these interrupts to their legacy equivalent to get rid of
328 * spurious interrupts.
329 */
330static int acpi_reroute_boot_interrupt(struct pci_dev *dev,
331 struct acpi_prt_entry *entry)
332{
333 if (noioapicquirk || noioapicreroute) {
334 return 0;
335 } else {
336 switch (bridge_has_boot_interrupt_variant(dev->bus)) {
337 case 0:
338 /* no rerouting necessary */
339 return 0;
340 case INTEL_IRQ_REROUTE_VARIANT:
341 /*
342 * Remap according to INTx routing table in 6700PXH
343 * specs, intel order number 302628-002, section
344 * 2.15.2. Other chipsets (80332, ...) have the same
345 * mapping and are handled here as well.
346 */
347 dev_info(&dev->dev, "PCI IRQ %d -> rerouted to legacy "
348 "IRQ %d\n", entry->index,
349 (entry->index % 4) + 16);
350 entry->index = (entry->index % 4) + 16;
351 return 1;
352 default:
353 dev_warn(&dev->dev, "Cannot reroute IRQ %d to legacy "
354 "IRQ: unknown mapping\n", entry->index);
355 return -1;
356 }
357 }
358}
359#endif /* CONFIG_X86_IO_APIC */
360
361static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin)
362{
363 struct acpi_prt_entry *entry;
364 struct pci_dev *bridge;
365 u8 bridge_pin, orig_pin = pin;
366
367 entry = acpi_pci_irq_find_prt_entry(dev, pin);
368 if (entry) {
369#ifdef CONFIG_X86_IO_APIC
370 acpi_reroute_boot_interrupt(dev, entry);
371#endif /* CONFIG_X86_IO_APIC */
372 ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %s[%c] _PRT entry\n",
373 pci_name(dev), pin_name(pin)));
374 return entry;
375 }
376
377 /*
378 * Attempt to derive an IRQ for this device from a parent bridge's
379 * PCI interrupt routing entry (eg. yenta bridge and add-in card bridge).
380 */
381 bridge = dev->bus->self;
382 while (bridge) {
383 pin = pci_swizzle_interrupt_pin(dev, pin);
384
385 if ((bridge->class >> 8) == PCI_CLASS_BRIDGE_CARDBUS) {
386 /* PC card has the same IRQ as its cardbridge */
387 bridge_pin = bridge->pin;
388 if (!bridge_pin) {
389 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
390 "No interrupt pin configured for device %s\n",
391 pci_name(bridge)));
392 return NULL;
393 }
394 pin = bridge_pin;
395 }
396
397 entry = acpi_pci_irq_find_prt_entry(bridge, pin);
398 if (entry) {
399 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
400 "Derived GSI for %s INT %c from %s\n",
401 pci_name(dev), pin_name(orig_pin),
402 pci_name(bridge)));
403 return entry;
404 }
405
406 dev = bridge;
407 bridge = dev->bus->self;
408 }
409
410 dev_warn(&dev->dev, "can't derive routing for PCI INT %c\n",
411 pin_name(orig_pin));
412 return NULL;
413}
414
415int acpi_pci_irq_enable(struct pci_dev *dev)
416{
417 struct acpi_prt_entry *entry;
418 int gsi;
419 u8 pin;
420 int triggering = ACPI_LEVEL_SENSITIVE;
421 int polarity = ACPI_ACTIVE_LOW;
422 char *link = NULL;
423 char link_desc[16];
424 int rc;
425
426 pin = dev->pin;
427 if (!pin) {
428 ACPI_DEBUG_PRINT((ACPI_DB_INFO,
429 "No interrupt pin configured for device %s\n",
430 pci_name(dev)));
431 return 0;
432 }
433
434 entry = acpi_pci_irq_lookup(dev, pin);
435 if (!entry) {
436 /*
437 * IDE legacy mode controller IRQs are magic. Why do compat
438 * extensions always make such a nasty mess.
439 */
440 if (dev->class >> 8 == PCI_CLASS_STORAGE_IDE &&
441 (dev->class & 0x05) == 0)
442 return 0;
443 }
444
445 if (entry) {
446 if (entry->link)
447 gsi = acpi_pci_link_allocate_irq(entry->link,
448 entry->index,
449 &triggering, &polarity,
450 &link);
451 else
452 gsi = entry->index;
453 } else
454 gsi = -1;
455
456 /*
457 * No IRQ known to the ACPI subsystem - maybe the BIOS /
458 * driver reported one, then use it. Exit in any case.
459 */
460 if (gsi < 0) {
461 u32 dev_gsi;
462 dev_warn(&dev->dev, "PCI INT %c: no GSI", pin_name(pin));
463 /* Interrupt Line values above 0xF are forbidden */
464 if (dev->irq > 0 && (dev->irq <= 0xF) &&
465 (acpi_isa_irq_to_gsi(dev->irq, &dev_gsi) == 0)) {
466 printk(" - using ISA IRQ %d\n", dev->irq);
467 acpi_register_gsi(&dev->dev, dev_gsi,
468 ACPI_LEVEL_SENSITIVE,
469 ACPI_ACTIVE_LOW);
470 return 0;
471 } else {
472 printk("\n");
473 return 0;
474 }
475 }
476
477 rc = acpi_register_gsi(&dev->dev, gsi, triggering, polarity);
478 if (rc < 0) {
479 dev_warn(&dev->dev, "PCI INT %c: failed to register GSI\n",
480 pin_name(pin));
481 return rc;
482 }
483 dev->irq = rc;
484
485 if (link)
486 snprintf(link_desc, sizeof(link_desc), " -> Link[%s]", link);
487 else
488 link_desc[0] = '\0';
489
490 dev_dbg(&dev->dev, "PCI INT %c%s -> GSI %u (%s, %s) -> IRQ %d\n",
491 pin_name(pin), link_desc, gsi,
492 (triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge",
493 (polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq);
494
495 return 0;
496}
497
498/* FIXME: implement x86/x86_64 version */
499void __attribute__ ((weak)) acpi_unregister_gsi(u32 i)
500{
501}
502
503void acpi_pci_irq_disable(struct pci_dev *dev)
504{
505 struct acpi_prt_entry *entry;
506 int gsi;
507 u8 pin;
508
509 pin = dev->pin;
510 if (!pin)
511 return;
512
513 entry = acpi_pci_irq_lookup(dev, pin);
514 if (!entry)
515 return;
516
517 if (entry->link)
518 gsi = acpi_pci_link_free_irq(entry->link);
519 else
520 gsi = entry->index;
521
522 /*
523 * TBD: It might be worth clearing dev->irq by magic constant
524 * (e.g. PCI_UNDEFINED_IRQ).
525 */
526
527 dev_dbg(&dev->dev, "PCI INT %c disabled\n", pin_name(pin));
528 acpi_unregister_gsi(gsi);
529}