summaryrefslogtreecommitdiff
path: root/drivers/acpi/pci_irq.c
blob: ff30ceca2203e3759dddd4d9ce5234ebbfea919a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  pci_irq.c - ACPI PCI Interrupt Routing ($Revision: 11 $)
 *
 *  Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com>
 *  Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com>
 *  Copyright (C) 2002       Dominik Brodowski <devel@brodo.de>
 *  (c) Copyright 2008 Hewlett-Packard Development Company, L.P.
 *	Bjorn Helgaas <bjorn.helgaas@hp.com>
 */

#define pr_fmt(fmt) "ACPI: PCI: " fmt

#include <linux/dmi.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/pm.h>
#include <linux/pci.h>
#include <linux/acpi.h>
#include <linux/slab.h>
#include <linux/interrupt.h>

struct acpi_prt_entry {
	struct acpi_pci_id	id;
	u8			pin;
	acpi_handle		link;
	u32			index;		/* GSI, or link _CRS index */
};

static inline char pin_name(int pin)
{
	return 'A' + pin - 1;
}

/* --------------------------------------------------------------------------
                         PCI IRQ Routing Table (PRT) Support
   -------------------------------------------------------------------------- */

/* http://bugzilla.kernel.org/show_bug.cgi?id=4773 */
static const struct dmi_system_id medion_md9580[] = {
	{
		.ident = "Medion MD9580-F laptop",
		.matches = {
			DMI_MATCH(DMI_SYS_VENDOR, "MEDIONNB"),
			DMI_MATCH(DMI_PRODUCT_NAME, "A555"),
		},
	},
	{ }
};

/* http://bugzilla.kernel.org/show_bug.cgi?id=5044 */
static const struct dmi_system_id dell_optiplex[] = {
	{
		.ident = "Dell Optiplex GX1",
		.matches = {
			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex GX1 600S+"),
		},
	},
	{ }
};

/* http://bugzilla.kernel.org/show_bug.cgi?id=10138 */
static const struct dmi_system_id hp_t5710[] = {
	{
		.ident = "HP t5710",
		.matches = {
			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
			DMI_MATCH(DMI_PRODUCT_NAME, "hp t5000 series"),
			DMI_MATCH(DMI_BOARD_NAME, "098Ch"),
		},
	},
	{ }
};

struct prt_quirk {
	const struct dmi_system_id *system;
	unsigned int		segment;
	unsigned int		bus;
	unsigned int		device;
	unsigned char		pin;
	const char		*source;	/* according to BIOS */
	const char		*actual_source;
};

#define PCI_INTX_PIN(c)		(c - 'A' + 1)

/*
 * These systems have incorrect _PRT entries.  The BIOS claims the PCI
 * interrupt at the listed segment/bus/device/pin is connected to the first
 * link device, but it is actually connected to the second.
 */
static const struct prt_quirk prt_quirks[] = {
	{ medion_md9580, 0, 0, 9, PCI_INTX_PIN('A'),
		"\\_SB_.PCI0.ISA_.LNKA",
		"\\_SB_.PCI0.ISA_.LNKB"},
	{ dell_optiplex, 0, 0, 0xd, PCI_INTX_PIN('A'),
		"\\_SB_.LNKB",
		"\\_SB_.LNKA"},
	{ hp_t5710, 0, 0, 1, PCI_INTX_PIN('A'),
		"\\_SB_.PCI0.LNK1",
		"\\_SB_.PCI0.LNK3"},
};

static void do_prt_fixups(struct acpi_prt_entry *entry,
			  struct acpi_pci_routing_table *prt)
{
	int i;
	const struct prt_quirk *quirk;

	for (i = 0; i < ARRAY_SIZE(prt_quirks); i++) {
		quirk = &prt_quirks[i];

		/* All current quirks involve link devices, not GSIs */
		if (dmi_check_system(quirk->system) &&
		    entry->id.segment == quirk->segment &&
		    entry->id.bus == quirk->bus &&
		    entry->id.device == quirk->device &&
		    entry->pin == quirk->pin &&
		    !strcmp(prt->source, quirk->source) &&
		    strlen(prt->source) >= strlen(quirk->actual_source)) {
			pr_warn("Firmware reports "
				"%04x:%02x:%02x PCI INT %c connected to %s; "
				"changing to %s\n",
				entry->id.segment, entry->id.bus,
				entry->id.device, pin_name(entry->pin),
				prt->source, quirk->actual_source);
			strcpy(prt->source, quirk->actual_source);
		}
	}
}

static int acpi_pci_irq_check_entry(acpi_handle handle, struct pci_dev *dev,
				  int pin, struct acpi_pci_routing_table *prt,
				  struct acpi_prt_entry **entry_ptr)
{
	int segment = pci_domain_nr(dev->bus);
	int bus = dev->bus->number;
	int device = pci_ari_enabled(dev->bus) ? 0 : PCI_SLOT(dev->devfn);
	struct acpi_prt_entry *entry;

	if (((prt->address >> 16) & 0xffff) != device ||
	    prt->pin + 1 != pin)
		return -ENODEV;

	entry = kzalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL);
	if (!entry)
		return -ENOMEM;

	/*
	 * Note that the _PRT uses 0=INTA, 1=INTB, etc, while PCI uses
	 * 1=INTA, 2=INTB.  We use the PCI encoding throughout, so convert
	 * it here.
	 */
	entry->id.segment = segment;
	entry->id.bus = bus;
	entry->id.device = (prt->address >> 16) & 0xFFFF;
	entry->pin = prt->pin + 1;

	do_prt_fixups(entry, prt);

	entry->index = prt->source_index;

	/*
	 * Type 1: Dynamic
	 * ---------------
	 * The 'source' field specifies the PCI interrupt link device used to
	 * configure the IRQ assigned to this slot|dev|pin.  The 'source_index'
	 * indicates which resource descriptor in the resource template (of
	 * the link device) this interrupt is allocated from.
	 *
	 * NOTE: Don't query the Link Device for IRQ information at this time
	 *       because Link Device enumeration may not have occurred yet
	 *       (e.g. exists somewhere 'below' this _PRT entry in the ACPI
	 *       namespace).
	 */
	if (prt->source[0])
		acpi_get_handle(handle, prt->source, &entry->link);

	/*
	 * Type 2: Static
	 * --------------
	 * The 'source' field is NULL, and the 'source_index' field specifies
	 * the IRQ value, which is hardwired to specific interrupt inputs on
	 * the interrupt controller.
	 */
	pr_debug("%04x:%02x:%02x[%c] -> %s[%d]\n",
		 entry->id.segment, entry->id.bus, entry->id.device,
		 pin_name(entry->pin), prt->source, entry->index);

	*entry_ptr = entry;

	return 0;
}

static int acpi_pci_irq_find_prt_entry(struct pci_dev *dev,
			  int pin, struct acpi_prt_entry **entry_ptr)
{
	acpi_status status;
	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
	struct acpi_pci_routing_table *entry;
	acpi_handle handle = NULL;

	if (dev->bus->bridge)
		handle = ACPI_HANDLE(dev->bus->bridge);

	if (!handle)
		return -ENODEV;

	/* 'handle' is the _PRT's parent (root bridge or PCI-PCI bridge) */
	status = acpi_get_irq_routing_table(handle, &buffer);
	if (ACPI_FAILURE(status)) {
		kfree(buffer.pointer);
		return -ENODEV;
	}

	entry = buffer.pointer;
	while (entry && (entry->length > 0)) {
		if (!acpi_pci_irq_check_entry(handle, dev, pin,
						 entry, entry_ptr))
			break;
		entry = (struct acpi_pci_routing_table *)
		    ((unsigned long)entry + entry->length);
	}

	kfree(buffer.pointer);
	return 0;
}

/* --------------------------------------------------------------------------
                          PCI Interrupt Routing Support
   -------------------------------------------------------------------------- */
#ifdef CONFIG_X86_IO_APIC
extern int noioapicquirk;
extern int noioapicreroute;

static int bridge_has_boot_interrupt_variant(struct pci_bus *bus)
{
	struct pci_bus *bus_it;

	for (bus_it = bus ; bus_it ; bus_it = bus_it->parent) {
		if (!bus_it->self)
			return 0;
		if (bus_it->self->irq_reroute_variant)
			return bus_it->self->irq_reroute_variant;
	}
	return 0;
}

/*
 * Some chipsets (e.g. Intel 6700PXH) generate a legacy INTx when the IRQ
 * entry in the chipset's IO-APIC is masked (as, e.g. the RT kernel does
 * during interrupt handling). When this INTx generation cannot be disabled,
 * we reroute these interrupts to their legacy equivalent to get rid of
 * spurious interrupts.
 */
static int acpi_reroute_boot_interrupt(struct pci_dev *dev,
				       struct acpi_prt_entry *entry)
{
	if (noioapicquirk || noioapicreroute) {
		return 0;
	} else {
		switch (bridge_has_boot_interrupt_variant(dev->bus)) {
		case 0:
			/* no rerouting necessary */
			return 0;
		case INTEL_IRQ_REROUTE_VARIANT:
			/*
			 * Remap according to INTx routing table in 6700PXH
			 * specs, intel order number 302628-002, section
			 * 2.15.2. Other chipsets (80332, ...) have the same
			 * mapping and are handled here as well.
			 */
			dev_info(&dev->dev, "PCI IRQ %d -> rerouted to legacy "
				 "IRQ %d\n", entry->index,
				 (entry->index % 4) + 16);
			entry->index = (entry->index % 4) + 16;
			return 1;
		default:
			dev_warn(&dev->dev, "Cannot reroute IRQ %d to legacy "
				 "IRQ: unknown mapping\n", entry->index);
			return -1;
		}
	}
}
#endif /* CONFIG_X86_IO_APIC */

static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin)
{
	struct acpi_prt_entry *entry = NULL;
	struct pci_dev *bridge;
	u8 bridge_pin, orig_pin = pin;
	int ret;

	ret = acpi_pci_irq_find_prt_entry(dev, pin, &entry);
	if (!ret && entry) {
#ifdef CONFIG_X86_IO_APIC
		acpi_reroute_boot_interrupt(dev, entry);
#endif /* CONFIG_X86_IO_APIC */
		dev_dbg(&dev->dev, "Found [%c] _PRT entry\n", pin_name(pin));
		return entry;
	}

	/*
	 * Attempt to derive an IRQ for this device from a parent bridge's
	 * PCI interrupt routing entry (eg. yenta bridge and add-in card bridge).
	 */
	bridge = dev->bus->self;
	while (bridge) {
		pin = pci_swizzle_interrupt_pin(dev, pin);

		if ((bridge->class >> 8) == PCI_CLASS_BRIDGE_CARDBUS) {
			/* PC card has the same IRQ as its cardbridge */
			bridge_pin = bridge->pin;
			if (!bridge_pin) {
				dev_dbg(&bridge->dev, "No interrupt pin configured\n");
				return NULL;
			}
			pin = bridge_pin;
		}

		ret = acpi_pci_irq_find_prt_entry(bridge, pin, &entry);
		if (!ret && entry) {
			dev_dbg(&dev->dev, "Derived GSI INT %c from %s\n",
				pin_name(orig_pin), pci_name(bridge));
			return entry;
		}

		dev = bridge;
		bridge = dev->bus->self;
	}

	dev_warn(&dev->dev, "can't derive routing for PCI INT %c\n",
		 pin_name(orig_pin));
	return NULL;
}

#if IS_ENABLED(CONFIG_ISA) || IS_ENABLED(CONFIG_EISA)
static int acpi_isa_register_gsi(struct pci_dev *dev)
{
	u32 dev_gsi;

	/* Interrupt Line values above 0xF are forbidden */
	if (dev->irq > 0 && (dev->irq <= 0xF) &&
	    acpi_isa_irq_available(dev->irq) &&
	    (acpi_isa_irq_to_gsi(dev->irq, &dev_gsi) == 0)) {
		dev_warn(&dev->dev, "PCI INT %c: no GSI - using ISA IRQ %d\n",
			 pin_name(dev->pin), dev->irq);
		acpi_register_gsi(&dev->dev, dev_gsi,
				  ACPI_LEVEL_SENSITIVE,
				  ACPI_ACTIVE_LOW);
		return 0;
	}
	return -EINVAL;
}
#else
static inline int acpi_isa_register_gsi(struct pci_dev *dev)
{
	return -ENODEV;
}
#endif

static inline bool acpi_pci_irq_valid(struct pci_dev *dev, u8 pin)
{
#ifdef CONFIG_X86
	/*
	 * On x86 irq line 0xff means "unknown" or "no connection"
	 * (PCI 3.0, Section 6.2.4, footnote on page 223).
	 */
	if (dev->irq == 0xff) {
		dev->irq = IRQ_NOTCONNECTED;
		dev_warn(&dev->dev, "PCI INT %c: not connected\n",
			 pin_name(pin));
		return false;
	}
#endif
	return true;
}

int acpi_pci_irq_enable(struct pci_dev *dev)
{
	struct acpi_prt_entry *entry;
	int gsi;
	u8 pin;
	int triggering = ACPI_LEVEL_SENSITIVE;
	/*
	 * On ARM systems with the GIC interrupt model, or LoongArch
	 * systems with the LPIC interrupt model, level interrupts
	 * are always polarity high by specification; PCI legacy
	 * IRQs lines are inverted before reaching the interrupt
	 * controller and must therefore be considered active high
	 * as default.
	 */
	int polarity = acpi_irq_model == ACPI_IRQ_MODEL_GIC ||
		       acpi_irq_model == ACPI_IRQ_MODEL_LPIC ?
				      ACPI_ACTIVE_HIGH : ACPI_ACTIVE_LOW;
	char *link = NULL;
	char link_desc[16];
	int rc;

	pin = dev->pin;
	if (!pin) {
		dev_dbg(&dev->dev, "No interrupt pin configured\n");
		return 0;
	}

	if (dev->irq_managed && dev->irq > 0)
		return 0;

	entry = acpi_pci_irq_lookup(dev, pin);
	if (!entry) {
		/*
		 * IDE legacy mode controller IRQs are magic. Why do compat
		 * extensions always make such a nasty mess.
		 */
		if (dev->class >> 8 == PCI_CLASS_STORAGE_IDE &&
				(dev->class & 0x05) == 0)
			return 0;
	}

	if (entry) {
		if (entry->link)
			gsi = acpi_pci_link_allocate_irq(entry->link,
							 entry->index,
							 &triggering, &polarity,
							 &link);
		else
			gsi = entry->index;
	} else
		gsi = -1;

	if (gsi < 0) {
		/*
		 * No IRQ known to the ACPI subsystem - maybe the BIOS /
		 * driver reported one, then use it. Exit in any case.
		 */
		if (!acpi_pci_irq_valid(dev, pin)) {
			kfree(entry);
			return 0;
		}

		if (acpi_isa_register_gsi(dev))
			dev_warn(&dev->dev, "PCI INT %c: no GSI\n",
				 pin_name(pin));

		kfree(entry);
		return 0;
	}

	rc = acpi_register_gsi(&dev->dev, gsi, triggering, polarity);
	if (rc < 0) {
		dev_warn(&dev->dev, "PCI INT %c: failed to register GSI\n",
			 pin_name(pin));
		kfree(entry);
		return rc;
	}
	dev->irq = rc;
	dev->irq_managed = 1;

	if (link)
		snprintf(link_desc, sizeof(link_desc), " -> Link[%s]", link);
	else
		link_desc[0] = '\0';

	dev_dbg(&dev->dev, "PCI INT %c%s -> GSI %u (%s, %s) -> IRQ %d\n",
		pin_name(pin), link_desc, gsi,
		(triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge",
		(polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq);

	kfree(entry);
	return 0;
}

void acpi_pci_irq_disable(struct pci_dev *dev)
{
	struct acpi_prt_entry *entry;
	int gsi;
	u8 pin;

	pin = dev->pin;
	if (!pin || !dev->irq_managed || dev->irq <= 0)
		return;

	/* Keep IOAPIC pin configuration when suspending */
	if (dev->dev.power.is_prepared)
		return;
#ifdef	CONFIG_PM
	if (dev->dev.power.runtime_status == RPM_SUSPENDING)
		return;
#endif

	entry = acpi_pci_irq_lookup(dev, pin);
	if (!entry)
		return;

	if (entry->link)
		gsi = acpi_pci_link_free_irq(entry->link);
	else
		gsi = entry->index;

	kfree(entry);

	/*
	 * TBD: It might be worth clearing dev->irq by magic constant
	 * (e.g. PCI_UNDEFINED_IRQ).
	 */

	dev_dbg(&dev->dev, "PCI INT %c disabled\n", pin_name(pin));
	if (gsi >= 0) {
		acpi_unregister_gsi(gsi);
		dev->irq_managed = 0;
	}
}