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v4.6
  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 * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 23 */
 24
 25
 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>
 32#include <linux/pm.h>
 33#include <linux/pci.h>
 34#include <linux/acpi.h>
 35#include <linux/slab.h>
 36#include <linux/interrupt.h>
 37
 38#define PREFIX "ACPI: "
 39
 40#define _COMPONENT		ACPI_PCI_COMPONENT
 41ACPI_MODULE_NAME("pci_irq");
 42
 43struct acpi_prt_entry {
 
 44	struct acpi_pci_id	id;
 45	u8			pin;
 46	acpi_handle		link;
 47	u32			index;		/* GSI, or link _CRS index */
 48};
 49
 50static inline char pin_name(int pin)
 51{
 52	return 'A' + pin - 1;
 53}
 54
 55/* --------------------------------------------------------------------------
 56                         PCI IRQ Routing Table (PRT) Support
 57   -------------------------------------------------------------------------- */
 58
 59/* http://bugzilla.kernel.org/show_bug.cgi?id=4773 */
 60static const struct dmi_system_id medion_md9580[] = {
 61	{
 62		.ident = "Medion MD9580-F laptop",
 63		.matches = {
 64			DMI_MATCH(DMI_SYS_VENDOR, "MEDIONNB"),
 65			DMI_MATCH(DMI_PRODUCT_NAME, "A555"),
 66		},
 67	},
 68	{ }
 69};
 70
 71/* http://bugzilla.kernel.org/show_bug.cgi?id=5044 */
 72static const struct dmi_system_id dell_optiplex[] = {
 73	{
 74		.ident = "Dell Optiplex GX1",
 75		.matches = {
 76			DMI_MATCH(DMI_SYS_VENDOR, "Dell Computer Corporation"),
 77			DMI_MATCH(DMI_PRODUCT_NAME, "OptiPlex GX1 600S+"),
 78		},
 79	},
 80	{ }
 81};
 82
 83/* http://bugzilla.kernel.org/show_bug.cgi?id=10138 */
 84static const struct dmi_system_id hp_t5710[] = {
 85	{
 86		.ident = "HP t5710",
 87		.matches = {
 88			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
 89			DMI_MATCH(DMI_PRODUCT_NAME, "hp t5000 series"),
 90			DMI_MATCH(DMI_BOARD_NAME, "098Ch"),
 91		},
 92	},
 93	{ }
 94};
 95
 96struct prt_quirk {
 97	const struct dmi_system_id *system;
 98	unsigned int		segment;
 99	unsigned int		bus;
100	unsigned int		device;
101	unsigned char		pin;
102	const char		*source;	/* according to BIOS */
103	const char		*actual_source;
104};
105
106#define PCI_INTX_PIN(c)		(c - 'A' + 1)
107
108/*
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.
112 */
113static 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'),
118		"\\_SB_.LNKB",
119		"\\_SB_.LNKA"},
120	{ hp_t5710, 0, 0, 1, PCI_INTX_PIN('A'),
121		"\\_SB_.PCI0.LNK1",
122		"\\_SB_.PCI0.LNK3"},
123};
124
125static void do_prt_fixups(struct acpi_prt_entry *entry,
126			  struct acpi_pci_routing_table *prt)
127{
128	int i;
129	const struct prt_quirk *quirk;
130
131	for (i = 0; i < ARRAY_SIZE(prt_quirks); i++) {
132		quirk = &prt_quirks[i];
133
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; "
144				"changing to %s\n",
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);
149		}
150	}
151}
152
153static 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)
156{
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;
161
162	if (((prt->address >> 16) & 0xffff) != device ||
163	    prt->pin + 1 != pin)
164		return -ENODEV;
165
166	entry = kzalloc(sizeof(struct acpi_prt_entry), GFP_KERNEL);
167	if (!entry)
168		return -ENOMEM;
169
170	/*
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
173	 * it here.
174	 */
175	entry->id.segment = segment;
176	entry->id.bus = bus;
177	entry->id.device = (prt->address >> 16) & 0xFFFF;
178	entry->pin = prt->pin + 1;
179
180	do_prt_fixups(entry, prt);
181
182	entry->index = prt->source_index;
183
184	/*
185	 * Type 1: Dynamic
186	 * ---------------
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.
191	 * 
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
195	 *       namespace).
196	 */
197	if (prt->source[0])
198		acpi_get_handle(handle, prt->source, &entry->link);
199
200	/*
201	 * Type 2: Static
202	 * --------------
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.
206	 */
207
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));
213
214	*entry_ptr = entry;
215
216	return 0;
217}
218
219static int acpi_pci_irq_find_prt_entry(struct pci_dev *dev,
220			  int pin, struct acpi_prt_entry **entry_ptr)
221{
222	acpi_status status;
223	struct acpi_buffer buffer = { ACPI_ALLOCATE_BUFFER, NULL };
224	struct acpi_pci_routing_table *entry;
225	acpi_handle handle = NULL;
226
227	if (dev->bus->bridge)
228		handle = ACPI_HANDLE(dev->bus->bridge);
229
230	if (!handle)
231		return -ENODEV;
232
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);
237		return -ENODEV;
238	}
239
240	entry = buffer.pointer;
241	while (entry && (entry->length > 0)) {
242		if (!acpi_pci_irq_check_entry(handle, dev, pin,
243						 entry, entry_ptr))
244			break;
245		entry = (struct acpi_pci_routing_table *)
246		    ((unsigned long)entry + entry->length);
247	}
248
249	kfree(buffer.pointer);
250	return 0;
251}
252
253/* --------------------------------------------------------------------------
254                          PCI Interrupt Routing Support
255   -------------------------------------------------------------------------- */
256#ifdef CONFIG_X86_IO_APIC
257extern int noioapicquirk;
258extern int noioapicreroute;
259
260static int bridge_has_boot_interrupt_variant(struct pci_bus *bus)
261{
262	struct pci_bus *bus_it;
263
264	for (bus_it = bus ; bus_it ; bus_it = bus_it->parent) {
265		if (!bus_it->self)
266			return 0;
267		if (bus_it->self->irq_reroute_variant)
268			return bus_it->self->irq_reroute_variant;
269	}
270	return 0;
271}
272
273/*
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.
279 */
280static int acpi_reroute_boot_interrupt(struct pci_dev *dev,
281				       struct acpi_prt_entry *entry)
282{
283	if (noioapicquirk || noioapicreroute) {
284		return 0;
285	} else {
286		switch (bridge_has_boot_interrupt_variant(dev->bus)) {
287		case 0:
288			/* no rerouting necessary */
289			return 0;
290		case INTEL_IRQ_REROUTE_VARIANT:
291			/*
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.
296			 */
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;
301			return 1;
302		default:
303			dev_warn(&dev->dev, "Cannot reroute IRQ %d to legacy "
304				 "IRQ: unknown mapping\n", entry->index);
305			return -1;
306		}
307	}
308}
309#endif /* CONFIG_X86_IO_APIC */
310
311static struct acpi_prt_entry *acpi_pci_irq_lookup(struct pci_dev *dev, int pin)
312{
313	struct acpi_prt_entry *entry = NULL;
314	struct pci_dev *bridge;
315	u8 bridge_pin, orig_pin = pin;
316	int ret;
317
318	ret = acpi_pci_irq_find_prt_entry(dev, pin, &entry);
319	if (!ret && 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)));
325		return entry;
326	}
327
328	/*
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).
331	 */
332	bridge = dev->bus->self;
333	while (bridge) {
334		pin = pci_swizzle_interrupt_pin(dev, pin);
335
336		if ((bridge->class >> 8) == PCI_CLASS_BRIDGE_CARDBUS) {
337			/* PC card has the same IRQ as its cardbridge */
338			bridge_pin = bridge->pin;
339			if (!bridge_pin) {
340				ACPI_DEBUG_PRINT((ACPI_DB_INFO,
341						  "No interrupt pin configured for device %s\n",
342						  pci_name(bridge)));
343				return NULL;
344			}
345			pin = bridge_pin;
346		}
347
348		ret = acpi_pci_irq_find_prt_entry(bridge, pin, &entry);
349		if (!ret && 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),
353					 pci_name(bridge)));
354			return entry;
355		}
356
357		dev = bridge;
358		bridge = dev->bus->self;
359	}
360
361	dev_warn(&dev->dev, "can't derive routing for PCI INT %c\n",
362		 pin_name(orig_pin));
363	return NULL;
364}
365
366#if IS_ENABLED(CONFIG_ISA) || IS_ENABLED(CONFIG_EISA)
367static int acpi_isa_register_gsi(struct pci_dev *dev)
368{
369	u32 dev_gsi;
370
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,
379				  ACPI_ACTIVE_LOW);
380		return 0;
381	}
382	return -EINVAL;
383}
384#else
385static inline int acpi_isa_register_gsi(struct pci_dev *dev)
386{
387	return -ENODEV;
388}
389#endif
390
391static inline bool acpi_pci_irq_valid(struct pci_dev *dev, u8 pin)
392{
393#ifdef CONFIG_X86
394	/*
395	 * On x86 irq line 0xff means "unknown" or "no connection"
396	 * (PCI 3.0, Section 6.2.4, footnote on page 223).
397	 */
398	if (dev->irq == 0xff) {
399		dev->irq = IRQ_NOTCONNECTED;
400		dev_warn(&dev->dev, "PCI INT %c: not connected\n",
401			 pin_name(pin));
402		return false;
403	}
404#endif
405	return true;
406}
407
408int acpi_pci_irq_enable(struct pci_dev *dev)
409{
410	struct acpi_prt_entry *entry;
411	int gsi;
412	u8 pin;
413	int triggering = ACPI_LEVEL_SENSITIVE;
414	int polarity = ACPI_ACTIVE_LOW;
415	char *link = NULL;
416	char link_desc[16];
417	int rc;
418
419	pin = dev->pin;
420	if (!pin) {
421		ACPI_DEBUG_PRINT((ACPI_DB_INFO,
422				  "No interrupt pin configured for device %s\n",
423				  pci_name(dev)));
424		return 0;
425	}
426
427	if (dev->irq_managed && dev->irq > 0)
428		return 0;
429
430	entry = acpi_pci_irq_lookup(dev, pin);
431	if (!entry) {
432		/*
433		 * IDE legacy mode controller IRQs are magic. Why do compat
434		 * extensions always make such a nasty mess.
435		 */
436		if (dev->class >> 8 == PCI_CLASS_STORAGE_IDE &&
437				(dev->class & 0x05) == 0)
438			return 0;
439	}
440
441	if (entry) {
442		if (entry->link)
443			gsi = acpi_pci_link_allocate_irq(entry->link,
444							 entry->index,
445							 &triggering, &polarity,
446							 &link);
447		else
448			gsi = entry->index;
449	} else
450		gsi = -1;
451
 
 
 
 
452	if (gsi < 0) {
453		/*
454		 * No IRQ known to the ACPI subsystem - maybe the BIOS /
455		 * driver reported one, then use it. Exit in any case.
456		 */
457		if (!acpi_pci_irq_valid(dev, pin))
458			return 0;
459
460		if (acpi_isa_register_gsi(dev))
461			dev_warn(&dev->dev, "PCI INT %c: no GSI\n",
462				 pin_name(pin));
463
464		kfree(entry);
465		return 0;
466	}
467
468	rc = acpi_register_gsi(&dev->dev, gsi, triggering, polarity);
469	if (rc < 0) {
470		dev_warn(&dev->dev, "PCI INT %c: failed to register GSI\n",
471			 pin_name(pin));
472		kfree(entry);
473		return rc;
474	}
475	dev->irq = rc;
476	dev->irq_managed = 1;
477
478	if (link)
479		snprintf(link_desc, sizeof(link_desc), " -> Link[%s]", link);
480	else
481		link_desc[0] = '\0';
482
483	dev_dbg(&dev->dev, "PCI INT %c%s -> GSI %u (%s, %s) -> IRQ %d\n",
484		pin_name(pin), link_desc, gsi,
485		(triggering == ACPI_LEVEL_SENSITIVE) ? "level" : "edge",
486		(polarity == ACPI_ACTIVE_LOW) ? "low" : "high", dev->irq);
487
488	kfree(entry);
489	return 0;
490}
491
492void acpi_pci_irq_disable(struct pci_dev *dev)
493{
494	struct acpi_prt_entry *entry;
495	int gsi;
496	u8 pin;
497
498	pin = dev->pin;
499	if (!pin || !dev->irq_managed || dev->irq <= 0)
500		return;
501
502	/* Keep IOAPIC pin configuration when suspending */
503	if (dev->dev.power.is_prepared)
504		return;
505#ifdef	CONFIG_PM
506	if (dev->dev.power.runtime_status == RPM_SUSPENDING)
507		return;
508#endif
509
510	entry = acpi_pci_irq_lookup(dev, pin);
511	if (!entry)
512		return;
513
514	if (entry->link)
515		gsi = acpi_pci_link_free_irq(entry->link);
516	else
517		gsi = entry->index;
518
519	kfree(entry);
520
521	/*
522	 * TBD: It might be worth clearing dev->irq by magic constant
523	 * (e.g. PCI_UNDEFINED_IRQ).
524	 */
525
526	dev_dbg(&dev->dev, "PCI INT %c disabled\n", pin_name(pin));
527	if (gsi >= 0) {
528		acpi_unregister_gsi(gsi);
529		dev->irq_managed = 0;
530	}
531}
v3.15
  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}