xref: /linux/drivers/acpi/pci_irq.c (revision d39d0ed196aa1685bb24771e92f78633c66ac9cb)
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/proc_fs.h>
36 #include <linux/spinlock.h>
37 #include <linux/pm.h>
38 #include <linux/pci.h>
39 #include <linux/acpi.h>
40 #include <linux/slab.h>
41 #include <acpi/acpi_bus.h>
42 #include <acpi/acpi_drivers.h>
43 
44 #define PREFIX "ACPI: "
45 
46 #define _COMPONENT		ACPI_PCI_COMPONENT
47 ACPI_MODULE_NAME("pci_irq");
48 
49 struct acpi_prt_entry {
50 	struct list_head	list;
51 	struct acpi_pci_id	id;
52 	u8			pin;
53 	acpi_handle		link;
54 	u32			index;		/* GSI, or link _CRS index */
55 };
56 
57 static LIST_HEAD(acpi_prt_list);
58 static DEFINE_SPINLOCK(acpi_prt_lock);
59 
60 static inline char pin_name(int pin)
61 {
62 	return 'A' + pin - 1;
63 }
64 
65 /* --------------------------------------------------------------------------
66                          PCI IRQ Routing Table (PRT) Support
67    -------------------------------------------------------------------------- */
68 
69 static struct acpi_prt_entry *acpi_pci_irq_find_prt_entry(struct pci_dev *dev,
70 							  int pin)
71 {
72 	struct acpi_prt_entry *entry;
73 	int segment = pci_domain_nr(dev->bus);
74 	int bus = dev->bus->number;
75 	int device = PCI_SLOT(dev->devfn);
76 
77 	spin_lock(&acpi_prt_lock);
78 	list_for_each_entry(entry, &acpi_prt_list, list) {
79 		if ((segment == entry->id.segment)
80 		    && (bus == entry->id.bus)
81 		    && (device == entry->id.device)
82 		    && (pin == entry->pin)) {
83 			spin_unlock(&acpi_prt_lock);
84 			return entry;
85 		}
86 	}
87 	spin_unlock(&acpi_prt_lock);
88 	return NULL;
89 }
90 
91 /* http://bugzilla.kernel.org/show_bug.cgi?id=4773 */
92 static const struct dmi_system_id medion_md9580[] = {
93 	{
94 		.ident = "Medion MD9580-F laptop",
95 		.matches = {
96 			DMI_MATCH(DMI_SYS_VENDOR, "MEDIONNB"),
97 			DMI_MATCH(DMI_PRODUCT_NAME, "A555"),
98 		},
99 	},
100 	{ }
101 };
102 
103 /* http://bugzilla.kernel.org/show_bug.cgi?id=5044 */
104 static const struct dmi_system_id dell_optiplex[] = {
105 	{
106 		.ident = "Dell Optiplex GX1",
107 		.matches = {
108 			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
109 			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex GX1 600S+"),
110 		},
111 	},
112 	{ }
113 };
114 
115 /* http://bugzilla.kernel.org/show_bug.cgi?id=10138 */
116 static const struct dmi_system_id hp_t5710[] = {
117 	{
118 		.ident = "HP t5710",
119 		.matches = {
120 			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
121 			DMI_MATCH(DMI_PRODUCT_NAME, "hp t5000 series"),
122 			DMI_MATCH(DMI_BOARD_NAME, "098Ch"),
123 		},
124 	},
125 	{ }
126 };
127 
128 struct prt_quirk {
129 	const struct dmi_system_id *system;
130 	unsigned int		segment;
131 	unsigned int		bus;
132 	unsigned int		device;
133 	unsigned char		pin;
134 	const char		*source;	/* according to BIOS */
135 	const char		*actual_source;
136 };
137 
138 #define PCI_INTX_PIN(c)		(c - 'A' + 1)
139 
140 /*
141  * These systems have incorrect _PRT entries.  The BIOS claims the PCI
142  * interrupt at the listed segment/bus/device/pin is connected to the first
143  * link device, but it is actually connected to the second.
144  */
145 static const struct prt_quirk prt_quirks[] = {
146 	{ medion_md9580, 0, 0, 9, PCI_INTX_PIN('A'),
147 		"\\_SB_.PCI0.ISA_.LNKA",
148 		"\\_SB_.PCI0.ISA_.LNKB"},
149 	{ dell_optiplex, 0, 0, 0xd, PCI_INTX_PIN('A'),
150 		"\\_SB_.LNKB",
151 		"\\_SB_.LNKA"},
152 	{ hp_t5710, 0, 0, 1, PCI_INTX_PIN('A'),
153 		"\\_SB_.PCI0.LNK1",
154 		"\\_SB_.PCI0.LNK3"},
155 };
156 
157 static void do_prt_fixups(struct acpi_prt_entry *entry,
158 			  struct acpi_pci_routing_table *prt)
159 {
160 	int i;
161 	const struct prt_quirk *quirk;
162 
163 	for (i = 0; i < ARRAY_SIZE(prt_quirks); i++) {
164 		quirk = &prt_quirks[i];
165 
166 		/* All current quirks involve link devices, not GSIs */
167 		if (!prt->source)
168 			continue;
169 
170 		if (dmi_check_system(quirk->system) &&
171 		    entry->id.segment == quirk->segment &&
172 		    entry->id.bus == quirk->bus &&
173 		    entry->id.device == quirk->device &&
174 		    entry->pin == quirk->pin &&
175 		    !strcmp(prt->source, quirk->source) &&
176 		    strlen(prt->source) >= strlen(quirk->actual_source)) {
177 			printk(KERN_WARNING PREFIX "firmware reports "
178 				"%04x:%02x:%02x PCI INT %c connected to %s; "
179 				"changing to %s\n",
180 				entry->id.segment, entry->id.bus,
181 				entry->id.device, pin_name(entry->pin),
182 				prt->source, quirk->actual_source);
183 			strcpy(prt->source, quirk->actual_source);
184 		}
185 	}
186 }
187 
188 static int acpi_pci_irq_add_entry(acpi_handle handle, struct pci_bus *bus,
189 				  struct acpi_pci_routing_table *prt)
190 {
191 	struct acpi_prt_entry *entry;
192 
193 	entry = kzalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL);
194 	if (!entry)
195 		return -ENOMEM;
196 
197 	/*
198 	 * Note that the _PRT uses 0=INTA, 1=INTB, etc, while PCI uses
199 	 * 1=INTA, 2=INTB.  We use the PCI encoding throughout, so convert
200 	 * it here.
201 	 */
202 	entry->id.segment = pci_domain_nr(bus);
203 	entry->id.bus = bus->number;
204 	entry->id.device = (prt->address >> 16) & 0xFFFF;
205 	entry->pin = prt->pin + 1;
206 
207 	do_prt_fixups(entry, prt);
208 
209 	entry->index = prt->source_index;
210 
211 	/*
212 	 * Type 1: Dynamic
213 	 * ---------------
214 	 * The 'source' field specifies the PCI interrupt link device used to
215 	 * configure the IRQ assigned to this slot|dev|pin.  The 'source_index'
216 	 * indicates which resource descriptor in the resource template (of
217 	 * the link device) this interrupt is allocated from.
218 	 *
219 	 * NOTE: Don't query the Link Device for IRQ information at this time
220 	 *       because Link Device enumeration may not have occurred yet
221 	 *       (e.g. exists somewhere 'below' this _PRT entry in the ACPI
222 	 *       namespace).
223 	 */
224 	if (prt->source[0])
225 		acpi_get_handle(handle, prt->source, &entry->link);
226 
227 	/*
228 	 * Type 2: Static
229 	 * --------------
230 	 * The 'source' field is NULL, and the 'source_index' field specifies
231 	 * the IRQ value, which is hardwired to specific interrupt inputs on
232 	 * the interrupt controller.
233 	 */
234 
235 	ACPI_DEBUG_PRINT_RAW((ACPI_DB_INFO,
236 			      "      %04x:%02x:%02x[%c] -> %s[%d]\n",
237 			      entry->id.segment, entry->id.bus,
238 			      entry->id.device, pin_name(entry->pin),
239 			      prt->source, entry->index));
240 
241 	spin_lock(&acpi_prt_lock);
242 	list_add_tail(&entry->list, &acpi_prt_list);
243 	spin_unlock(&acpi_prt_lock);
244 
245 	return 0;
246 }
247 
248 int acpi_pci_irq_add_prt(acpi_handle handle, struct pci_bus *bus)
249 {
250 	acpi_status status;
251 	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
252 	struct acpi_pci_routing_table *entry;
253 
254 	/* 'handle' is the _PRT's parent (root bridge or PCI-PCI bridge) */
255 	status = acpi_get_name(handle, ACPI_FULL_PATHNAME, &buffer);
256 	if (ACPI_FAILURE(status))
257 		return -ENODEV;
258 
259 	printk(KERN_DEBUG "ACPI: PCI Interrupt Routing Table [%s._PRT]\n",
260 	       (char *) buffer.pointer);
261 
262 	kfree(buffer.pointer);
263 
264 	buffer.length = ACPI_ALLOCATE_BUFFER;
265 	buffer.pointer = NULL;
266 
267 	status = acpi_get_irq_routing_table(handle, &buffer);
268 	if (ACPI_FAILURE(status)) {
269 		ACPI_EXCEPTION((AE_INFO, status, "Evaluating _PRT [%s]",
270 				acpi_format_exception(status)));
271 		kfree(buffer.pointer);
272 		return -ENODEV;
273 	}
274 
275 	entry = buffer.pointer;
276 	while (entry && (entry->length > 0)) {
277 		acpi_pci_irq_add_entry(handle, bus, entry);
278 		entry = (struct acpi_pci_routing_table *)
279 		    ((unsigned long)entry + entry->length);
280 	}
281 
282 	kfree(buffer.pointer);
283 	return 0;
284 }
285 
286 void acpi_pci_irq_del_prt(struct pci_bus *bus)
287 {
288 	struct acpi_prt_entry *entry, *tmp;
289 
290 	printk(KERN_DEBUG
291 	       "ACPI: Delete PCI Interrupt Routing Table for %04x:%02x\n",
292 	       pci_domain_nr(bus), bus->number);
293 	spin_lock(&acpi_prt_lock);
294 	list_for_each_entry_safe(entry, tmp, &acpi_prt_list, list) {
295 		if (pci_domain_nr(bus) == entry->id.segment
296 			&& bus->number == entry->id.bus) {
297 			list_del(&entry->list);
298 			kfree(entry);
299 		}
300 	}
301 	spin_unlock(&acpi_prt_lock);
302 }
303 
304 /* --------------------------------------------------------------------------
305                           PCI Interrupt Routing Support
306    -------------------------------------------------------------------------- */
307 static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin)
308 {
309 	struct acpi_prt_entry *entry;
310 	struct pci_dev *bridge;
311 	u8 bridge_pin, orig_pin = pin;
312 
313 	entry = acpi_pci_irq_find_prt_entry(dev, pin);
314 	if (entry) {
315 		ACPI_DEBUG_PRINT((ACPI_DB_INFO, "Found %s[%c] _PRT entry\n",
316 				  pci_name(dev), pin_name(pin)));
317 		return entry;
318 	}
319 
320 	/*
321 	 * Attempt to derive an IRQ for this device from a parent bridge's
322 	 * PCI interrupt routing entry (eg. yenta bridge and add-in card bridge).
323 	 */
324 	bridge = dev->bus->self;
325 	while (bridge) {
326 		pin = pci_swizzle_interrupt_pin(dev, pin);
327 
328 		if ((bridge->class >> 8) == PCI_CLASS_BRIDGE_CARDBUS) {
329 			/* PC card has the same IRQ as its cardbridge */
330 			bridge_pin = bridge->pin;
331 			if (!bridge_pin) {
332 				ACPI_DEBUG_PRINT((ACPI_DB_INFO,
333 						  "No interrupt pin configured for device %s\n",
334 						  pci_name(bridge)));
335 				return NULL;
336 			}
337 			pin = bridge_pin;
338 		}
339 
340 		entry = acpi_pci_irq_find_prt_entry(bridge, pin);
341 		if (entry) {
342 			ACPI_DEBUG_PRINT((ACPI_DB_INFO,
343 					 "Derived GSI for %s INT %c from %s\n",
344 					 pci_name(dev), pin_name(orig_pin),
345 					 pci_name(bridge)));
346 			return entry;
347 		}
348 
349 		dev = bridge;
350 		bridge = dev->bus->self;
351 	}
352 
353 	dev_warn(&dev->dev, "can't derive routing for PCI INT %c\n",
354 		 pin_name(orig_pin));
355 	return NULL;
356 }
357 
358 int acpi_pci_irq_enable(struct pci_dev *dev)
359 {
360 	struct acpi_prt_entry *entry;
361 	int gsi;
362 	u8 pin;
363 	int triggering = ACPI_LEVEL_SENSITIVE;
364 	int polarity = ACPI_ACTIVE_LOW;
365 	char *link = NULL;
366 	char link_desc[16];
367 	int rc;
368 
369 	pin = dev->pin;
370 	if (!pin) {
371 		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
372 				  "No interrupt pin configured for device %s\n",
373 				  pci_name(dev)));
374 		return 0;
375 	}
376 
377 	entry = acpi_pci_irq_lookup(dev, pin);
378 	if (!entry) {
379 		/*
380 		 * IDE legacy mode controller IRQs are magic. Why do compat
381 		 * extensions always make such a nasty mess.
382 		 */
383 		if (dev->class >> 8 == PCI_CLASS_STORAGE_IDE &&
384 				(dev->class & 0x05) == 0)
385 			return 0;
386 	}
387 
388 	if (entry) {
389 		if (entry->link)
390 			gsi = acpi_pci_link_allocate_irq(entry->link,
391 							 entry->index,
392 							 &triggering, &polarity,
393 							 &link);
394 		else
395 			gsi = entry->index;
396 	} else
397 		gsi = -1;
398 
399 	/*
400 	 * No IRQ known to the ACPI subsystem - maybe the BIOS /
401 	 * driver reported one, then use it. Exit in any case.
402 	 */
403 	if (gsi < 0) {
404 		u32 dev_gsi;
405 		dev_warn(&dev->dev, "PCI INT %c: no GSI", pin_name(pin));
406 		/* Interrupt Line values above 0xF are forbidden */
407 		if (dev->irq > 0 && (dev->irq <= 0xF) &&
408 		    (acpi_isa_irq_to_gsi(dev->irq, &dev_gsi) == 0)) {
409 			printk(" - using ISA IRQ %d\n", dev->irq);
410 			acpi_register_gsi(&dev->dev, dev_gsi,
411 					  ACPI_LEVEL_SENSITIVE,
412 					  ACPI_ACTIVE_LOW);
413 			return 0;
414 		} else {
415 			printk("\n");
416 			return 0;
417 		}
418 	}
419 
420 	rc = acpi_register_gsi(&dev->dev, gsi, triggering, polarity);
421 	if (rc < 0) {
422 		dev_warn(&dev->dev, "PCI INT %c: failed to register GSI\n",
423 			 pin_name(pin));
424 		return rc;
425 	}
426 	dev->irq = rc;
427 
428 	if (link)
429 		snprintf(link_desc, sizeof(link_desc), " -> Link[%s]", link);
430 	else
431 		link_desc[0] = '\0';
432 
433 	dev_info(&dev->dev, "PCI INT %c%s -> GSI %u (%s, %s) -> IRQ %d\n",
434 		 pin_name(pin), link_desc, gsi,
435 		 (triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge",
436 		 (polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq);
437 
438 	return 0;
439 }
440 
441 /* FIXME: implement x86/x86_64 version */
442 void __attribute__ ((weak)) acpi_unregister_gsi(u32 i)
443 {
444 }
445 
446 void acpi_pci_irq_disable(struct pci_dev *dev)
447 {
448 	struct acpi_prt_entry *entry;
449 	int gsi;
450 	u8 pin;
451 
452 	pin = dev->pin;
453 	if (!pin)
454 		return;
455 
456 	entry = acpi_pci_irq_lookup(dev, pin);
457 	if (!entry)
458 		return;
459 
460 	if (entry->link)
461 		gsi = acpi_pci_link_free_irq(entry->link);
462 	else
463 		gsi = entry->index;
464 
465 	/*
466 	 * TBD: It might be worth clearing dev->irq by magic constant
467 	 * (e.g. PCI_UNDEFINED_IRQ).
468 	 */
469 
470 	dev_info(&dev->dev, "PCI INT %c disabled\n", pin_name(pin));
471 	acpi_unregister_gsi(gsi);
472 }
473