xref: /openbmc/linux/arch/x86/pci/irq.c (revision 588b48ca)
1 /*
2  *	Low-Level PCI Support for PC -- Routing of Interrupts
3  *
4  *	(c) 1999--2000 Martin Mares <mj@ucw.cz>
5  */
6 
7 #include <linux/types.h>
8 #include <linux/kernel.h>
9 #include <linux/pci.h>
10 #include <linux/init.h>
11 #include <linux/interrupt.h>
12 #include <linux/dmi.h>
13 #include <linux/io.h>
14 #include <linux/smp.h>
15 #include <asm/io_apic.h>
16 #include <linux/irq.h>
17 #include <linux/acpi.h>
18 #include <asm/pci_x86.h>
19 
20 #define PIRQ_SIGNATURE	(('$' << 0) + ('P' << 8) + ('I' << 16) + ('R' << 24))
21 #define PIRQ_VERSION 0x0100
22 
23 static int broken_hp_bios_irq9;
24 static int acer_tm360_irqrouting;
25 
26 static struct irq_routing_table *pirq_table;
27 
28 static int pirq_enable_irq(struct pci_dev *dev);
29 static void pirq_disable_irq(struct pci_dev *dev);
30 
31 /*
32  * Never use: 0, 1, 2 (timer, keyboard, and cascade)
33  * Avoid using: 13, 14 and 15 (FP error and IDE).
34  * Penalize: 3, 4, 6, 7, 12 (known ISA uses: serial, floppy, parallel and mouse)
35  */
36 unsigned int pcibios_irq_mask = 0xfff8;
37 
38 static int pirq_penalty[16] = {
39 	1000000, 1000000, 1000000, 1000, 1000, 0, 1000, 1000,
40 	0, 0, 0, 0, 1000, 100000, 100000, 100000
41 };
42 
43 struct irq_router {
44 	char *name;
45 	u16 vendor, device;
46 	int (*get)(struct pci_dev *router, struct pci_dev *dev, int pirq);
47 	int (*set)(struct pci_dev *router, struct pci_dev *dev, int pirq,
48 		int new);
49 };
50 
51 struct irq_router_handler {
52 	u16 vendor;
53 	int (*probe)(struct irq_router *r, struct pci_dev *router, u16 device);
54 };
55 
56 int (*pcibios_enable_irq)(struct pci_dev *dev) = pirq_enable_irq;
57 void (*pcibios_disable_irq)(struct pci_dev *dev) = pirq_disable_irq;
58 
59 /*
60  *  Check passed address for the PCI IRQ Routing Table signature
61  *  and perform checksum verification.
62  */
63 
64 static inline struct irq_routing_table *pirq_check_routing_table(u8 *addr)
65 {
66 	struct irq_routing_table *rt;
67 	int i;
68 	u8 sum;
69 
70 	rt = (struct irq_routing_table *) addr;
71 	if (rt->signature != PIRQ_SIGNATURE ||
72 	    rt->version != PIRQ_VERSION ||
73 	    rt->size % 16 ||
74 	    rt->size < sizeof(struct irq_routing_table))
75 		return NULL;
76 	sum = 0;
77 	for (i = 0; i < rt->size; i++)
78 		sum += addr[i];
79 	if (!sum) {
80 		DBG(KERN_DEBUG "PCI: Interrupt Routing Table found at 0x%p\n",
81 			rt);
82 		return rt;
83 	}
84 	return NULL;
85 }
86 
87 
88 
89 /*
90  *  Search 0xf0000 -- 0xfffff for the PCI IRQ Routing Table.
91  */
92 
93 static struct irq_routing_table * __init pirq_find_routing_table(void)
94 {
95 	u8 *addr;
96 	struct irq_routing_table *rt;
97 
98 	if (pirq_table_addr) {
99 		rt = pirq_check_routing_table((u8 *) __va(pirq_table_addr));
100 		if (rt)
101 			return rt;
102 		printk(KERN_WARNING "PCI: PIRQ table NOT found at pirqaddr\n");
103 	}
104 	for (addr = (u8 *) __va(0xf0000); addr < (u8 *) __va(0x100000); addr += 16) {
105 		rt = pirq_check_routing_table(addr);
106 		if (rt)
107 			return rt;
108 	}
109 	return NULL;
110 }
111 
112 /*
113  *  If we have a IRQ routing table, use it to search for peer host
114  *  bridges.  It's a gross hack, but since there are no other known
115  *  ways how to get a list of buses, we have to go this way.
116  */
117 
118 static void __init pirq_peer_trick(void)
119 {
120 	struct irq_routing_table *rt = pirq_table;
121 	u8 busmap[256];
122 	int i;
123 	struct irq_info *e;
124 
125 	memset(busmap, 0, sizeof(busmap));
126 	for (i = 0; i < (rt->size - sizeof(struct irq_routing_table)) / sizeof(struct irq_info); i++) {
127 		e = &rt->slots[i];
128 #ifdef DEBUG
129 		{
130 			int j;
131 			DBG(KERN_DEBUG "%02x:%02x slot=%02x", e->bus, e->devfn/8, e->slot);
132 			for (j = 0; j < 4; j++)
133 				DBG(" %d:%02x/%04x", j, e->irq[j].link, e->irq[j].bitmap);
134 			DBG("\n");
135 		}
136 #endif
137 		busmap[e->bus] = 1;
138 	}
139 	for (i = 1; i < 256; i++) {
140 		if (!busmap[i] || pci_find_bus(0, i))
141 			continue;
142 		pcibios_scan_root(i);
143 	}
144 	pcibios_last_bus = -1;
145 }
146 
147 /*
148  *  Code for querying and setting of IRQ routes on various interrupt routers.
149  */
150 
151 void eisa_set_level_irq(unsigned int irq)
152 {
153 	unsigned char mask = 1 << (irq & 7);
154 	unsigned int port = 0x4d0 + (irq >> 3);
155 	unsigned char val;
156 	static u16 eisa_irq_mask;
157 
158 	if (irq >= 16 || (1 << irq) & eisa_irq_mask)
159 		return;
160 
161 	eisa_irq_mask |= (1 << irq);
162 	printk(KERN_DEBUG "PCI: setting IRQ %u as level-triggered\n", irq);
163 	val = inb(port);
164 	if (!(val & mask)) {
165 		DBG(KERN_DEBUG " -> edge");
166 		outb(val | mask, port);
167 	}
168 }
169 
170 /*
171  * Common IRQ routing practice: nibbles in config space,
172  * offset by some magic constant.
173  */
174 static unsigned int read_config_nybble(struct pci_dev *router, unsigned offset, unsigned nr)
175 {
176 	u8 x;
177 	unsigned reg = offset + (nr >> 1);
178 
179 	pci_read_config_byte(router, reg, &x);
180 	return (nr & 1) ? (x >> 4) : (x & 0xf);
181 }
182 
183 static void write_config_nybble(struct pci_dev *router, unsigned offset,
184 	unsigned nr, unsigned int val)
185 {
186 	u8 x;
187 	unsigned reg = offset + (nr >> 1);
188 
189 	pci_read_config_byte(router, reg, &x);
190 	x = (nr & 1) ? ((x & 0x0f) | (val << 4)) : ((x & 0xf0) | val);
191 	pci_write_config_byte(router, reg, x);
192 }
193 
194 /*
195  * ALI pirq entries are damn ugly, and completely undocumented.
196  * This has been figured out from pirq tables, and it's not a pretty
197  * picture.
198  */
199 static int pirq_ali_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
200 {
201 	static const unsigned char irqmap[16] = { 0, 9, 3, 10, 4, 5, 7, 6, 1, 11, 0, 12, 0, 14, 0, 15 };
202 
203 	WARN_ON_ONCE(pirq > 16);
204 	return irqmap[read_config_nybble(router, 0x48, pirq-1)];
205 }
206 
207 static int pirq_ali_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
208 {
209 	static const unsigned char irqmap[16] = { 0, 8, 0, 2, 4, 5, 7, 6, 0, 1, 3, 9, 11, 0, 13, 15 };
210 	unsigned int val = irqmap[irq];
211 
212 	WARN_ON_ONCE(pirq > 16);
213 	if (val) {
214 		write_config_nybble(router, 0x48, pirq-1, val);
215 		return 1;
216 	}
217 	return 0;
218 }
219 
220 /*
221  * The Intel PIIX4 pirq rules are fairly simple: "pirq" is
222  * just a pointer to the config space.
223  */
224 static int pirq_piix_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
225 {
226 	u8 x;
227 
228 	pci_read_config_byte(router, pirq, &x);
229 	return (x < 16) ? x : 0;
230 }
231 
232 static int pirq_piix_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
233 {
234 	pci_write_config_byte(router, pirq, irq);
235 	return 1;
236 }
237 
238 /*
239  * The VIA pirq rules are nibble-based, like ALI,
240  * but without the ugly irq number munging.
241  * However, PIRQD is in the upper instead of lower 4 bits.
242  */
243 static int pirq_via_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
244 {
245 	return read_config_nybble(router, 0x55, pirq == 4 ? 5 : pirq);
246 }
247 
248 static int pirq_via_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
249 {
250 	write_config_nybble(router, 0x55, pirq == 4 ? 5 : pirq, irq);
251 	return 1;
252 }
253 
254 /*
255  * The VIA pirq rules are nibble-based, like ALI,
256  * but without the ugly irq number munging.
257  * However, for 82C586, nibble map is different .
258  */
259 static int pirq_via586_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
260 {
261 	static const unsigned int pirqmap[5] = { 3, 2, 5, 1, 1 };
262 
263 	WARN_ON_ONCE(pirq > 5);
264 	return read_config_nybble(router, 0x55, pirqmap[pirq-1]);
265 }
266 
267 static int pirq_via586_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
268 {
269 	static const unsigned int pirqmap[5] = { 3, 2, 5, 1, 1 };
270 
271 	WARN_ON_ONCE(pirq > 5);
272 	write_config_nybble(router, 0x55, pirqmap[pirq-1], irq);
273 	return 1;
274 }
275 
276 /*
277  * ITE 8330G pirq rules are nibble-based
278  * FIXME: pirqmap may be { 1, 0, 3, 2 },
279  * 	  2+3 are both mapped to irq 9 on my system
280  */
281 static int pirq_ite_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
282 {
283 	static const unsigned char pirqmap[4] = { 1, 0, 2, 3 };
284 
285 	WARN_ON_ONCE(pirq > 4);
286 	return read_config_nybble(router, 0x43, pirqmap[pirq-1]);
287 }
288 
289 static int pirq_ite_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
290 {
291 	static const unsigned char pirqmap[4] = { 1, 0, 2, 3 };
292 
293 	WARN_ON_ONCE(pirq > 4);
294 	write_config_nybble(router, 0x43, pirqmap[pirq-1], irq);
295 	return 1;
296 }
297 
298 /*
299  * OPTI: high four bits are nibble pointer..
300  * I wonder what the low bits do?
301  */
302 static int pirq_opti_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
303 {
304 	return read_config_nybble(router, 0xb8, pirq >> 4);
305 }
306 
307 static int pirq_opti_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
308 {
309 	write_config_nybble(router, 0xb8, pirq >> 4, irq);
310 	return 1;
311 }
312 
313 /*
314  * Cyrix: nibble offset 0x5C
315  * 0x5C bits 7:4 is INTB bits 3:0 is INTA
316  * 0x5D bits 7:4 is INTD bits 3:0 is INTC
317  */
318 static int pirq_cyrix_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
319 {
320 	return read_config_nybble(router, 0x5C, (pirq-1)^1);
321 }
322 
323 static int pirq_cyrix_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
324 {
325 	write_config_nybble(router, 0x5C, (pirq-1)^1, irq);
326 	return 1;
327 }
328 
329 /*
330  *	PIRQ routing for SiS 85C503 router used in several SiS chipsets.
331  *	We have to deal with the following issues here:
332  *	- vendors have different ideas about the meaning of link values
333  *	- some onboard devices (integrated in the chipset) have special
334  *	  links and are thus routed differently (i.e. not via PCI INTA-INTD)
335  *	- different revision of the router have a different layout for
336  *	  the routing registers, particularly for the onchip devices
337  *
338  *	For all routing registers the common thing is we have one byte
339  *	per routeable link which is defined as:
340  *		 bit 7      IRQ mapping enabled (0) or disabled (1)
341  *		 bits [6:4] reserved (sometimes used for onchip devices)
342  *		 bits [3:0] IRQ to map to
343  *		     allowed: 3-7, 9-12, 14-15
344  *		     reserved: 0, 1, 2, 8, 13
345  *
346  *	The config-space registers located at 0x41/0x42/0x43/0x44 are
347  *	always used to route the normal PCI INT A/B/C/D respectively.
348  *	Apparently there are systems implementing PCI routing table using
349  *	link values 0x01-0x04 and others using 0x41-0x44 for PCI INTA..D.
350  *	We try our best to handle both link mappings.
351  *
352  *	Currently (2003-05-21) it appears most SiS chipsets follow the
353  *	definition of routing registers from the SiS-5595 southbridge.
354  *	According to the SiS 5595 datasheets the revision id's of the
355  *	router (ISA-bridge) should be 0x01 or 0xb0.
356  *
357  *	Furthermore we've also seen lspci dumps with revision 0x00 and 0xb1.
358  *	Looks like these are used in a number of SiS 5xx/6xx/7xx chipsets.
359  *	They seem to work with the current routing code. However there is
360  *	some concern because of the two USB-OHCI HCs (original SiS 5595
361  *	had only one). YMMV.
362  *
363  *	Onchip routing for router rev-id 0x01/0xb0 and probably 0x00/0xb1:
364  *
365  *	0x61:	IDEIRQ:
366  *		bits [6:5] must be written 01
367  *		bit 4 channel-select primary (0), secondary (1)
368  *
369  *	0x62:	USBIRQ:
370  *		bit 6 OHCI function disabled (0), enabled (1)
371  *
372  *	0x6a:	ACPI/SCI IRQ: bits 4-6 reserved
373  *
374  *	0x7e:	Data Acq. Module IRQ - bits 4-6 reserved
375  *
376  *	We support USBIRQ (in addition to INTA-INTD) and keep the
377  *	IDE, ACPI and DAQ routing untouched as set by the BIOS.
378  *
379  *	Currently the only reported exception is the new SiS 65x chipset
380  *	which includes the SiS 69x southbridge. Here we have the 85C503
381  *	router revision 0x04 and there are changes in the register layout
382  *	mostly related to the different USB HCs with USB 2.0 support.
383  *
384  *	Onchip routing for router rev-id 0x04 (try-and-error observation)
385  *
386  *	0x60/0x61/0x62/0x63:	1xEHCI and 3xOHCI (companion) USB-HCs
387  *				bit 6-4 are probably unused, not like 5595
388  */
389 
390 #define PIRQ_SIS_IRQ_MASK	0x0f
391 #define PIRQ_SIS_IRQ_DISABLE	0x80
392 #define PIRQ_SIS_USB_ENABLE	0x40
393 
394 static int pirq_sis_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
395 {
396 	u8 x;
397 	int reg;
398 
399 	reg = pirq;
400 	if (reg >= 0x01 && reg <= 0x04)
401 		reg += 0x40;
402 	pci_read_config_byte(router, reg, &x);
403 	return (x & PIRQ_SIS_IRQ_DISABLE) ? 0 : (x & PIRQ_SIS_IRQ_MASK);
404 }
405 
406 static int pirq_sis_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
407 {
408 	u8 x;
409 	int reg;
410 
411 	reg = pirq;
412 	if (reg >= 0x01 && reg <= 0x04)
413 		reg += 0x40;
414 	pci_read_config_byte(router, reg, &x);
415 	x &= ~(PIRQ_SIS_IRQ_MASK | PIRQ_SIS_IRQ_DISABLE);
416 	x |= irq ? irq: PIRQ_SIS_IRQ_DISABLE;
417 	pci_write_config_byte(router, reg, x);
418 	return 1;
419 }
420 
421 
422 /*
423  * VLSI: nibble offset 0x74 - educated guess due to routing table and
424  *       config space of VLSI 82C534 PCI-bridge/router (1004:0102)
425  *       Tested on HP OmniBook 800 covering PIRQ 1, 2, 4, 8 for onboard
426  *       devices, PIRQ 3 for non-pci(!) soundchip and (untested) PIRQ 6
427  *       for the busbridge to the docking station.
428  */
429 
430 static int pirq_vlsi_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
431 {
432 	WARN_ON_ONCE(pirq >= 9);
433 	if (pirq > 8) {
434 		dev_info(&dev->dev, "VLSI router PIRQ escape (%d)\n", pirq);
435 		return 0;
436 	}
437 	return read_config_nybble(router, 0x74, pirq-1);
438 }
439 
440 static int pirq_vlsi_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
441 {
442 	WARN_ON_ONCE(pirq >= 9);
443 	if (pirq > 8) {
444 		dev_info(&dev->dev, "VLSI router PIRQ escape (%d)\n", pirq);
445 		return 0;
446 	}
447 	write_config_nybble(router, 0x74, pirq-1, irq);
448 	return 1;
449 }
450 
451 /*
452  * ServerWorks: PCI interrupts mapped to system IRQ lines through Index
453  * and Redirect I/O registers (0x0c00 and 0x0c01).  The Index register
454  * format is (PCIIRQ## | 0x10), e.g.: PCIIRQ10=0x1a.  The Redirect
455  * register is a straight binary coding of desired PIC IRQ (low nibble).
456  *
457  * The 'link' value in the PIRQ table is already in the correct format
458  * for the Index register.  There are some special index values:
459  * 0x00 for ACPI (SCI), 0x01 for USB, 0x02 for IDE0, 0x04 for IDE1,
460  * and 0x03 for SMBus.
461  */
462 static int pirq_serverworks_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
463 {
464 	outb(pirq, 0xc00);
465 	return inb(0xc01) & 0xf;
466 }
467 
468 static int pirq_serverworks_set(struct pci_dev *router, struct pci_dev *dev,
469 	int pirq, int irq)
470 {
471 	outb(pirq, 0xc00);
472 	outb(irq, 0xc01);
473 	return 1;
474 }
475 
476 /* Support for AMD756 PCI IRQ Routing
477  * Jhon H. Caicedo <jhcaiced@osso.org.co>
478  * Jun/21/2001 0.2.0 Release, fixed to use "nybble" functions... (jhcaiced)
479  * Jun/19/2001 Alpha Release 0.1.0 (jhcaiced)
480  * The AMD756 pirq rules are nibble-based
481  * offset 0x56 0-3 PIRQA  4-7  PIRQB
482  * offset 0x57 0-3 PIRQC  4-7  PIRQD
483  */
484 static int pirq_amd756_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
485 {
486 	u8 irq;
487 	irq = 0;
488 	if (pirq <= 4)
489 		irq = read_config_nybble(router, 0x56, pirq - 1);
490 	dev_info(&dev->dev,
491 		 "AMD756: dev [%04x:%04x], router PIRQ %d get IRQ %d\n",
492 		 dev->vendor, dev->device, pirq, irq);
493 	return irq;
494 }
495 
496 static int pirq_amd756_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
497 {
498 	dev_info(&dev->dev,
499 		 "AMD756: dev [%04x:%04x], router PIRQ %d set IRQ %d\n",
500 		 dev->vendor, dev->device, pirq, irq);
501 	if (pirq <= 4)
502 		write_config_nybble(router, 0x56, pirq - 1, irq);
503 	return 1;
504 }
505 
506 /*
507  * PicoPower PT86C523
508  */
509 static int pirq_pico_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
510 {
511 	outb(0x10 + ((pirq - 1) >> 1), 0x24);
512 	return ((pirq - 1) & 1) ? (inb(0x26) >> 4) : (inb(0x26) & 0xf);
513 }
514 
515 static int pirq_pico_set(struct pci_dev *router, struct pci_dev *dev, int pirq,
516 			int irq)
517 {
518 	unsigned int x;
519 	outb(0x10 + ((pirq - 1) >> 1), 0x24);
520 	x = inb(0x26);
521 	x = ((pirq - 1) & 1) ? ((x & 0x0f) | (irq << 4)) : ((x & 0xf0) | (irq));
522 	outb(x, 0x26);
523 	return 1;
524 }
525 
526 #ifdef CONFIG_PCI_BIOS
527 
528 static int pirq_bios_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
529 {
530 	struct pci_dev *bridge;
531 	int pin = pci_get_interrupt_pin(dev, &bridge);
532 	return pcibios_set_irq_routing(bridge, pin - 1, irq);
533 }
534 
535 #endif
536 
537 static __init int intel_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
538 {
539 	static struct pci_device_id __initdata pirq_440gx[] = {
540 		{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443GX_0) },
541 		{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443GX_2) },
542 		{ },
543 	};
544 
545 	/* 440GX has a proprietary PIRQ router -- don't use it */
546 	if (pci_dev_present(pirq_440gx))
547 		return 0;
548 
549 	switch (device) {
550 	case PCI_DEVICE_ID_INTEL_82371FB_0:
551 	case PCI_DEVICE_ID_INTEL_82371SB_0:
552 	case PCI_DEVICE_ID_INTEL_82371AB_0:
553 	case PCI_DEVICE_ID_INTEL_82371MX:
554 	case PCI_DEVICE_ID_INTEL_82443MX_0:
555 	case PCI_DEVICE_ID_INTEL_82801AA_0:
556 	case PCI_DEVICE_ID_INTEL_82801AB_0:
557 	case PCI_DEVICE_ID_INTEL_82801BA_0:
558 	case PCI_DEVICE_ID_INTEL_82801BA_10:
559 	case PCI_DEVICE_ID_INTEL_82801CA_0:
560 	case PCI_DEVICE_ID_INTEL_82801CA_12:
561 	case PCI_DEVICE_ID_INTEL_82801DB_0:
562 	case PCI_DEVICE_ID_INTEL_82801E_0:
563 	case PCI_DEVICE_ID_INTEL_82801EB_0:
564 	case PCI_DEVICE_ID_INTEL_ESB_1:
565 	case PCI_DEVICE_ID_INTEL_ICH6_0:
566 	case PCI_DEVICE_ID_INTEL_ICH6_1:
567 	case PCI_DEVICE_ID_INTEL_ICH7_0:
568 	case PCI_DEVICE_ID_INTEL_ICH7_1:
569 	case PCI_DEVICE_ID_INTEL_ICH7_30:
570 	case PCI_DEVICE_ID_INTEL_ICH7_31:
571 	case PCI_DEVICE_ID_INTEL_TGP_LPC:
572 	case PCI_DEVICE_ID_INTEL_ESB2_0:
573 	case PCI_DEVICE_ID_INTEL_ICH8_0:
574 	case PCI_DEVICE_ID_INTEL_ICH8_1:
575 	case PCI_DEVICE_ID_INTEL_ICH8_2:
576 	case PCI_DEVICE_ID_INTEL_ICH8_3:
577 	case PCI_DEVICE_ID_INTEL_ICH8_4:
578 	case PCI_DEVICE_ID_INTEL_ICH9_0:
579 	case PCI_DEVICE_ID_INTEL_ICH9_1:
580 	case PCI_DEVICE_ID_INTEL_ICH9_2:
581 	case PCI_DEVICE_ID_INTEL_ICH9_3:
582 	case PCI_DEVICE_ID_INTEL_ICH9_4:
583 	case PCI_DEVICE_ID_INTEL_ICH9_5:
584 	case PCI_DEVICE_ID_INTEL_EP80579_0:
585 	case PCI_DEVICE_ID_INTEL_ICH10_0:
586 	case PCI_DEVICE_ID_INTEL_ICH10_1:
587 	case PCI_DEVICE_ID_INTEL_ICH10_2:
588 	case PCI_DEVICE_ID_INTEL_ICH10_3:
589 	case PCI_DEVICE_ID_INTEL_PATSBURG_LPC_0:
590 	case PCI_DEVICE_ID_INTEL_PATSBURG_LPC_1:
591 		r->name = "PIIX/ICH";
592 		r->get = pirq_piix_get;
593 		r->set = pirq_piix_set;
594 		return 1;
595 	}
596 
597 	if ((device >= PCI_DEVICE_ID_INTEL_5_3400_SERIES_LPC_MIN &&
598 	     device <= PCI_DEVICE_ID_INTEL_5_3400_SERIES_LPC_MAX)
599 	||  (device >= PCI_DEVICE_ID_INTEL_COUGARPOINT_LPC_MIN &&
600 	     device <= PCI_DEVICE_ID_INTEL_COUGARPOINT_LPC_MAX)
601 	||  (device >= PCI_DEVICE_ID_INTEL_DH89XXCC_LPC_MIN &&
602 	     device <= PCI_DEVICE_ID_INTEL_DH89XXCC_LPC_MAX)
603 	||  (device >= PCI_DEVICE_ID_INTEL_PANTHERPOINT_LPC_MIN &&
604 	     device <= PCI_DEVICE_ID_INTEL_PANTHERPOINT_LPC_MAX)) {
605 		r->name = "PIIX/ICH";
606 		r->get = pirq_piix_get;
607 		r->set = pirq_piix_set;
608 		return 1;
609 	}
610 
611 	return 0;
612 }
613 
614 static __init int via_router_probe(struct irq_router *r,
615 				struct pci_dev *router, u16 device)
616 {
617 	/* FIXME: We should move some of the quirk fixup stuff here */
618 
619 	/*
620 	 * workarounds for some buggy BIOSes
621 	 */
622 	if (device == PCI_DEVICE_ID_VIA_82C586_0) {
623 		switch (router->device) {
624 		case PCI_DEVICE_ID_VIA_82C686:
625 			/*
626 			 * Asus k7m bios wrongly reports 82C686A
627 			 * as 586-compatible
628 			 */
629 			device = PCI_DEVICE_ID_VIA_82C686;
630 			break;
631 		case PCI_DEVICE_ID_VIA_8235:
632 			/**
633 			 * Asus a7v-x bios wrongly reports 8235
634 			 * as 586-compatible
635 			 */
636 			device = PCI_DEVICE_ID_VIA_8235;
637 			break;
638 		case PCI_DEVICE_ID_VIA_8237:
639 			/**
640 			 * Asus a7v600 bios wrongly reports 8237
641 			 * as 586-compatible
642 			 */
643 			device = PCI_DEVICE_ID_VIA_8237;
644 			break;
645 		}
646 	}
647 
648 	switch (device) {
649 	case PCI_DEVICE_ID_VIA_82C586_0:
650 		r->name = "VIA";
651 		r->get = pirq_via586_get;
652 		r->set = pirq_via586_set;
653 		return 1;
654 	case PCI_DEVICE_ID_VIA_82C596:
655 	case PCI_DEVICE_ID_VIA_82C686:
656 	case PCI_DEVICE_ID_VIA_8231:
657 	case PCI_DEVICE_ID_VIA_8233A:
658 	case PCI_DEVICE_ID_VIA_8235:
659 	case PCI_DEVICE_ID_VIA_8237:
660 		/* FIXME: add new ones for 8233/5 */
661 		r->name = "VIA";
662 		r->get = pirq_via_get;
663 		r->set = pirq_via_set;
664 		return 1;
665 	}
666 	return 0;
667 }
668 
669 static __init int vlsi_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
670 {
671 	switch (device) {
672 	case PCI_DEVICE_ID_VLSI_82C534:
673 		r->name = "VLSI 82C534";
674 		r->get = pirq_vlsi_get;
675 		r->set = pirq_vlsi_set;
676 		return 1;
677 	}
678 	return 0;
679 }
680 
681 
682 static __init int serverworks_router_probe(struct irq_router *r,
683 		struct pci_dev *router, u16 device)
684 {
685 	switch (device) {
686 	case PCI_DEVICE_ID_SERVERWORKS_OSB4:
687 	case PCI_DEVICE_ID_SERVERWORKS_CSB5:
688 		r->name = "ServerWorks";
689 		r->get = pirq_serverworks_get;
690 		r->set = pirq_serverworks_set;
691 		return 1;
692 	}
693 	return 0;
694 }
695 
696 static __init int sis_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
697 {
698 	if (device != PCI_DEVICE_ID_SI_503)
699 		return 0;
700 
701 	r->name = "SIS";
702 	r->get = pirq_sis_get;
703 	r->set = pirq_sis_set;
704 	return 1;
705 }
706 
707 static __init int cyrix_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
708 {
709 	switch (device) {
710 	case PCI_DEVICE_ID_CYRIX_5520:
711 		r->name = "NatSemi";
712 		r->get = pirq_cyrix_get;
713 		r->set = pirq_cyrix_set;
714 		return 1;
715 	}
716 	return 0;
717 }
718 
719 static __init int opti_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
720 {
721 	switch (device) {
722 	case PCI_DEVICE_ID_OPTI_82C700:
723 		r->name = "OPTI";
724 		r->get = pirq_opti_get;
725 		r->set = pirq_opti_set;
726 		return 1;
727 	}
728 	return 0;
729 }
730 
731 static __init int ite_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
732 {
733 	switch (device) {
734 	case PCI_DEVICE_ID_ITE_IT8330G_0:
735 		r->name = "ITE";
736 		r->get = pirq_ite_get;
737 		r->set = pirq_ite_set;
738 		return 1;
739 	}
740 	return 0;
741 }
742 
743 static __init int ali_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
744 {
745 	switch (device) {
746 	case PCI_DEVICE_ID_AL_M1533:
747 	case PCI_DEVICE_ID_AL_M1563:
748 		r->name = "ALI";
749 		r->get = pirq_ali_get;
750 		r->set = pirq_ali_set;
751 		return 1;
752 	}
753 	return 0;
754 }
755 
756 static __init int amd_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
757 {
758 	switch (device) {
759 	case PCI_DEVICE_ID_AMD_VIPER_740B:
760 		r->name = "AMD756";
761 		break;
762 	case PCI_DEVICE_ID_AMD_VIPER_7413:
763 		r->name = "AMD766";
764 		break;
765 	case PCI_DEVICE_ID_AMD_VIPER_7443:
766 		r->name = "AMD768";
767 		break;
768 	default:
769 		return 0;
770 	}
771 	r->get = pirq_amd756_get;
772 	r->set = pirq_amd756_set;
773 	return 1;
774 }
775 
776 static __init int pico_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
777 {
778 	switch (device) {
779 	case PCI_DEVICE_ID_PICOPOWER_PT86C523:
780 		r->name = "PicoPower PT86C523";
781 		r->get = pirq_pico_get;
782 		r->set = pirq_pico_set;
783 		return 1;
784 
785 	case PCI_DEVICE_ID_PICOPOWER_PT86C523BBP:
786 		r->name = "PicoPower PT86C523 rev. BB+";
787 		r->get = pirq_pico_get;
788 		r->set = pirq_pico_set;
789 		return 1;
790 	}
791 	return 0;
792 }
793 
794 static __initdata struct irq_router_handler pirq_routers[] = {
795 	{ PCI_VENDOR_ID_INTEL, intel_router_probe },
796 	{ PCI_VENDOR_ID_AL, ali_router_probe },
797 	{ PCI_VENDOR_ID_ITE, ite_router_probe },
798 	{ PCI_VENDOR_ID_VIA, via_router_probe },
799 	{ PCI_VENDOR_ID_OPTI, opti_router_probe },
800 	{ PCI_VENDOR_ID_SI, sis_router_probe },
801 	{ PCI_VENDOR_ID_CYRIX, cyrix_router_probe },
802 	{ PCI_VENDOR_ID_VLSI, vlsi_router_probe },
803 	{ PCI_VENDOR_ID_SERVERWORKS, serverworks_router_probe },
804 	{ PCI_VENDOR_ID_AMD, amd_router_probe },
805 	{ PCI_VENDOR_ID_PICOPOWER, pico_router_probe },
806 	/* Someone with docs needs to add the ATI Radeon IGP */
807 	{ 0, NULL }
808 };
809 static struct irq_router pirq_router;
810 static struct pci_dev *pirq_router_dev;
811 
812 
813 /*
814  *	FIXME: should we have an option to say "generic for
815  *	chipset" ?
816  */
817 
818 static void __init pirq_find_router(struct irq_router *r)
819 {
820 	struct irq_routing_table *rt = pirq_table;
821 	struct irq_router_handler *h;
822 
823 #ifdef CONFIG_PCI_BIOS
824 	if (!rt->signature) {
825 		printk(KERN_INFO "PCI: Using BIOS for IRQ routing\n");
826 		r->set = pirq_bios_set;
827 		r->name = "BIOS";
828 		return;
829 	}
830 #endif
831 
832 	/* Default unless a driver reloads it */
833 	r->name = "default";
834 	r->get = NULL;
835 	r->set = NULL;
836 
837 	DBG(KERN_DEBUG "PCI: Attempting to find IRQ router for [%04x:%04x]\n",
838 	    rt->rtr_vendor, rt->rtr_device);
839 
840 	pirq_router_dev = pci_get_bus_and_slot(rt->rtr_bus, rt->rtr_devfn);
841 	if (!pirq_router_dev) {
842 		DBG(KERN_DEBUG "PCI: Interrupt router not found at "
843 			"%02x:%02x\n", rt->rtr_bus, rt->rtr_devfn);
844 		return;
845 	}
846 
847 	for (h = pirq_routers; h->vendor; h++) {
848 		/* First look for a router match */
849 		if (rt->rtr_vendor == h->vendor &&
850 			h->probe(r, pirq_router_dev, rt->rtr_device))
851 			break;
852 		/* Fall back to a device match */
853 		if (pirq_router_dev->vendor == h->vendor &&
854 			h->probe(r, pirq_router_dev, pirq_router_dev->device))
855 			break;
856 	}
857 	dev_info(&pirq_router_dev->dev, "%s IRQ router [%04x:%04x]\n",
858 		 pirq_router.name,
859 		 pirq_router_dev->vendor, pirq_router_dev->device);
860 
861 	/* The device remains referenced for the kernel lifetime */
862 }
863 
864 static struct irq_info *pirq_get_info(struct pci_dev *dev)
865 {
866 	struct irq_routing_table *rt = pirq_table;
867 	int entries = (rt->size - sizeof(struct irq_routing_table)) /
868 		sizeof(struct irq_info);
869 	struct irq_info *info;
870 
871 	for (info = rt->slots; entries--; info++)
872 		if (info->bus == dev->bus->number &&
873 			PCI_SLOT(info->devfn) == PCI_SLOT(dev->devfn))
874 			return info;
875 	return NULL;
876 }
877 
878 static int pcibios_lookup_irq(struct pci_dev *dev, int assign)
879 {
880 	u8 pin;
881 	struct irq_info *info;
882 	int i, pirq, newirq;
883 	int irq = 0;
884 	u32 mask;
885 	struct irq_router *r = &pirq_router;
886 	struct pci_dev *dev2 = NULL;
887 	char *msg = NULL;
888 
889 	/* Find IRQ pin */
890 	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
891 	if (!pin) {
892 		dev_dbg(&dev->dev, "no interrupt pin\n");
893 		return 0;
894 	}
895 
896 	if (io_apic_assign_pci_irqs)
897 		return 0;
898 
899 	/* Find IRQ routing entry */
900 
901 	if (!pirq_table)
902 		return 0;
903 
904 	info = pirq_get_info(dev);
905 	if (!info) {
906 		dev_dbg(&dev->dev, "PCI INT %c not found in routing table\n",
907 			'A' + pin - 1);
908 		return 0;
909 	}
910 	pirq = info->irq[pin - 1].link;
911 	mask = info->irq[pin - 1].bitmap;
912 	if (!pirq) {
913 		dev_dbg(&dev->dev, "PCI INT %c not routed\n", 'A' + pin - 1);
914 		return 0;
915 	}
916 	dev_dbg(&dev->dev, "PCI INT %c -> PIRQ %02x, mask %04x, excl %04x",
917 		'A' + pin - 1, pirq, mask, pirq_table->exclusive_irqs);
918 	mask &= pcibios_irq_mask;
919 
920 	/* Work around broken HP Pavilion Notebooks which assign USB to
921 	   IRQ 9 even though it is actually wired to IRQ 11 */
922 
923 	if (broken_hp_bios_irq9 && pirq == 0x59 && dev->irq == 9) {
924 		dev->irq = 11;
925 		pci_write_config_byte(dev, PCI_INTERRUPT_LINE, 11);
926 		r->set(pirq_router_dev, dev, pirq, 11);
927 	}
928 
929 	/* same for Acer Travelmate 360, but with CB and irq 11 -> 10 */
930 	if (acer_tm360_irqrouting && dev->irq == 11 &&
931 		dev->vendor == PCI_VENDOR_ID_O2) {
932 		pirq = 0x68;
933 		mask = 0x400;
934 		dev->irq = r->get(pirq_router_dev, dev, pirq);
935 		pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq);
936 	}
937 
938 	/*
939 	 * Find the best IRQ to assign: use the one
940 	 * reported by the device if possible.
941 	 */
942 	newirq = dev->irq;
943 	if (newirq && !((1 << newirq) & mask)) {
944 		if (pci_probe & PCI_USE_PIRQ_MASK)
945 			newirq = 0;
946 		else
947 			dev_warn(&dev->dev, "IRQ %d doesn't match PIRQ mask "
948 				 "%#x; try pci=usepirqmask\n", newirq, mask);
949 	}
950 	if (!newirq && assign) {
951 		for (i = 0; i < 16; i++) {
952 			if (!(mask & (1 << i)))
953 				continue;
954 			if (pirq_penalty[i] < pirq_penalty[newirq] &&
955 				can_request_irq(i, IRQF_SHARED))
956 				newirq = i;
957 		}
958 	}
959 	dev_dbg(&dev->dev, "PCI INT %c -> newirq %d", 'A' + pin - 1, newirq);
960 
961 	/* Check if it is hardcoded */
962 	if ((pirq & 0xf0) == 0xf0) {
963 		irq = pirq & 0xf;
964 		msg = "hardcoded";
965 	} else if (r->get && (irq = r->get(pirq_router_dev, dev, pirq)) && \
966 	((!(pci_probe & PCI_USE_PIRQ_MASK)) || ((1 << irq) & mask))) {
967 		msg = "found";
968 		eisa_set_level_irq(irq);
969 	} else if (newirq && r->set &&
970 		(dev->class >> 8) != PCI_CLASS_DISPLAY_VGA) {
971 		if (r->set(pirq_router_dev, dev, pirq, newirq)) {
972 			eisa_set_level_irq(newirq);
973 			msg = "assigned";
974 			irq = newirq;
975 		}
976 	}
977 
978 	if (!irq) {
979 		if (newirq && mask == (1 << newirq)) {
980 			msg = "guessed";
981 			irq = newirq;
982 		} else {
983 			dev_dbg(&dev->dev, "can't route interrupt\n");
984 			return 0;
985 		}
986 	}
987 	dev_info(&dev->dev, "%s PCI INT %c -> IRQ %d\n", msg, 'A' + pin - 1, irq);
988 
989 	/* Update IRQ for all devices with the same pirq value */
990 	for_each_pci_dev(dev2) {
991 		pci_read_config_byte(dev2, PCI_INTERRUPT_PIN, &pin);
992 		if (!pin)
993 			continue;
994 
995 		info = pirq_get_info(dev2);
996 		if (!info)
997 			continue;
998 		if (info->irq[pin - 1].link == pirq) {
999 			/*
1000 			 * We refuse to override the dev->irq
1001 			 * information. Give a warning!
1002 			 */
1003 			if (dev2->irq && dev2->irq != irq && \
1004 			(!(pci_probe & PCI_USE_PIRQ_MASK) || \
1005 			((1 << dev2->irq) & mask))) {
1006 #ifndef CONFIG_PCI_MSI
1007 				dev_info(&dev2->dev, "IRQ routing conflict: "
1008 					 "have IRQ %d, want IRQ %d\n",
1009 					 dev2->irq, irq);
1010 #endif
1011 				continue;
1012 			}
1013 			dev2->irq = irq;
1014 			pirq_penalty[irq]++;
1015 			if (dev != dev2)
1016 				dev_info(&dev->dev, "sharing IRQ %d with %s\n",
1017 					 irq, pci_name(dev2));
1018 		}
1019 	}
1020 	return 1;
1021 }
1022 
1023 void __init pcibios_fixup_irqs(void)
1024 {
1025 	struct pci_dev *dev = NULL;
1026 	u8 pin;
1027 
1028 	DBG(KERN_DEBUG "PCI: IRQ fixup\n");
1029 	for_each_pci_dev(dev) {
1030 		/*
1031 		 * If the BIOS has set an out of range IRQ number, just
1032 		 * ignore it.  Also keep track of which IRQ's are
1033 		 * already in use.
1034 		 */
1035 		if (dev->irq >= 16) {
1036 			dev_dbg(&dev->dev, "ignoring bogus IRQ %d\n", dev->irq);
1037 			dev->irq = 0;
1038 		}
1039 		/*
1040 		 * If the IRQ is already assigned to a PCI device,
1041 		 * ignore its ISA use penalty
1042 		 */
1043 		if (pirq_penalty[dev->irq] >= 100 &&
1044 				pirq_penalty[dev->irq] < 100000)
1045 			pirq_penalty[dev->irq] = 0;
1046 		pirq_penalty[dev->irq]++;
1047 	}
1048 
1049 	if (io_apic_assign_pci_irqs)
1050 		return;
1051 
1052 	dev = NULL;
1053 	for_each_pci_dev(dev) {
1054 		pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
1055 		if (!pin)
1056 			continue;
1057 
1058 		/*
1059 		 * Still no IRQ? Try to lookup one...
1060 		 */
1061 		if (!dev->irq)
1062 			pcibios_lookup_irq(dev, 0);
1063 	}
1064 }
1065 
1066 /*
1067  * Work around broken HP Pavilion Notebooks which assign USB to
1068  * IRQ 9 even though it is actually wired to IRQ 11
1069  */
1070 static int __init fix_broken_hp_bios_irq9(const struct dmi_system_id *d)
1071 {
1072 	if (!broken_hp_bios_irq9) {
1073 		broken_hp_bios_irq9 = 1;
1074 		printk(KERN_INFO "%s detected - fixing broken IRQ routing\n",
1075 			d->ident);
1076 	}
1077 	return 0;
1078 }
1079 
1080 /*
1081  * Work around broken Acer TravelMate 360 Notebooks which assign
1082  * Cardbus to IRQ 11 even though it is actually wired to IRQ 10
1083  */
1084 static int __init fix_acer_tm360_irqrouting(const struct dmi_system_id *d)
1085 {
1086 	if (!acer_tm360_irqrouting) {
1087 		acer_tm360_irqrouting = 1;
1088 		printk(KERN_INFO "%s detected - fixing broken IRQ routing\n",
1089 			d->ident);
1090 	}
1091 	return 0;
1092 }
1093 
1094 static struct dmi_system_id __initdata pciirq_dmi_table[] = {
1095 	{
1096 		.callback = fix_broken_hp_bios_irq9,
1097 		.ident = "HP Pavilion N5400 Series Laptop",
1098 		.matches = {
1099 			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1100 			DMI_MATCH(DMI_BIOS_VERSION, "GE.M1.03"),
1101 			DMI_MATCH(DMI_PRODUCT_VERSION,
1102 				"HP Pavilion Notebook Model GE"),
1103 			DMI_MATCH(DMI_BOARD_VERSION, "OmniBook N32N-736"),
1104 		},
1105 	},
1106 	{
1107 		.callback = fix_acer_tm360_irqrouting,
1108 		.ident = "Acer TravelMate 36x Laptop",
1109 		.matches = {
1110 			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
1111 			DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 360"),
1112 		},
1113 	},
1114 	{ }
1115 };
1116 
1117 void __init pcibios_irq_init(void)
1118 {
1119 	DBG(KERN_DEBUG "PCI: IRQ init\n");
1120 
1121 	if (raw_pci_ops == NULL)
1122 		return;
1123 
1124 	dmi_check_system(pciirq_dmi_table);
1125 
1126 	pirq_table = pirq_find_routing_table();
1127 
1128 #ifdef CONFIG_PCI_BIOS
1129 	if (!pirq_table && (pci_probe & PCI_BIOS_IRQ_SCAN))
1130 		pirq_table = pcibios_get_irq_routing_table();
1131 #endif
1132 	if (pirq_table) {
1133 		pirq_peer_trick();
1134 		pirq_find_router(&pirq_router);
1135 		if (pirq_table->exclusive_irqs) {
1136 			int i;
1137 			for (i = 0; i < 16; i++)
1138 				if (!(pirq_table->exclusive_irqs & (1 << i)))
1139 					pirq_penalty[i] += 100;
1140 		}
1141 		/*
1142 		 * If we're using the I/O APIC, avoid using the PCI IRQ
1143 		 * routing table
1144 		 */
1145 		if (io_apic_assign_pci_irqs)
1146 			pirq_table = NULL;
1147 	}
1148 
1149 	x86_init.pci.fixup_irqs();
1150 
1151 	if (io_apic_assign_pci_irqs && pci_routeirq) {
1152 		struct pci_dev *dev = NULL;
1153 		/*
1154 		 * PCI IRQ routing is set up by pci_enable_device(), but we
1155 		 * also do it here in case there are still broken drivers that
1156 		 * don't use pci_enable_device().
1157 		 */
1158 		printk(KERN_INFO "PCI: Routing PCI interrupts for all devices because \"pci=routeirq\" specified\n");
1159 		for_each_pci_dev(dev)
1160 			pirq_enable_irq(dev);
1161 	}
1162 }
1163 
1164 static void pirq_penalize_isa_irq(int irq, int active)
1165 {
1166 	/*
1167 	 *  If any ISAPnP device reports an IRQ in its list of possible
1168 	 *  IRQ's, we try to avoid assigning it to PCI devices.
1169 	 */
1170 	if (irq < 16) {
1171 		if (active)
1172 			pirq_penalty[irq] += 1000;
1173 		else
1174 			pirq_penalty[irq] += 100;
1175 	}
1176 }
1177 
1178 void pcibios_penalize_isa_irq(int irq, int active)
1179 {
1180 #ifdef CONFIG_ACPI
1181 	if (!acpi_noirq)
1182 		acpi_penalize_isa_irq(irq, active);
1183 	else
1184 #endif
1185 		pirq_penalize_isa_irq(irq, active);
1186 }
1187 
1188 static int pirq_enable_irq(struct pci_dev *dev)
1189 {
1190 	u8 pin = 0;
1191 
1192 	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
1193 	if (pin && !pcibios_lookup_irq(dev, 1)) {
1194 		char *msg = "";
1195 
1196 		if (!io_apic_assign_pci_irqs && dev->irq)
1197 			return 0;
1198 
1199 		if (io_apic_assign_pci_irqs) {
1200 #ifdef CONFIG_X86_IO_APIC
1201 			struct pci_dev *temp_dev;
1202 			int irq;
1203 			struct io_apic_irq_attr irq_attr;
1204 
1205 			irq = IO_APIC_get_PCI_irq_vector(dev->bus->number,
1206 						PCI_SLOT(dev->devfn),
1207 						pin - 1, &irq_attr);
1208 			/*
1209 			 * Busses behind bridges are typically not listed in the MP-table.
1210 			 * In this case we have to look up the IRQ based on the parent bus,
1211 			 * parent slot, and pin number. The SMP code detects such bridged
1212 			 * busses itself so we should get into this branch reliably.
1213 			 */
1214 			temp_dev = dev;
1215 			while (irq < 0 && dev->bus->parent) { /* go back to the bridge */
1216 				struct pci_dev *bridge = dev->bus->self;
1217 
1218 				pin = pci_swizzle_interrupt_pin(dev, pin);
1219 				irq = IO_APIC_get_PCI_irq_vector(bridge->bus->number,
1220 						PCI_SLOT(bridge->devfn),
1221 						pin - 1, &irq_attr);
1222 				if (irq >= 0)
1223 					dev_warn(&dev->dev, "using bridge %s "
1224 						 "INT %c to get IRQ %d\n",
1225 						 pci_name(bridge), 'A' + pin - 1,
1226 						 irq);
1227 				dev = bridge;
1228 			}
1229 			dev = temp_dev;
1230 			if (irq >= 0) {
1231 				dev->irq = irq;
1232 				dev_info(&dev->dev, "PCI->APIC IRQ transform: "
1233 					 "INT %c -> IRQ %d\n", 'A' + pin - 1, irq);
1234 				return 0;
1235 			} else
1236 				msg = "; probably buggy MP table";
1237 #endif
1238 		} else if (pci_probe & PCI_BIOS_IRQ_SCAN)
1239 			msg = "";
1240 		else
1241 			msg = "; please try using pci=biosirq";
1242 
1243 		/*
1244 		 * With IDE legacy devices the IRQ lookup failure is not
1245 		 * a problem..
1246 		 */
1247 		if (dev->class >> 8 == PCI_CLASS_STORAGE_IDE &&
1248 				!(dev->class & 0x5))
1249 			return 0;
1250 
1251 		dev_warn(&dev->dev, "can't find IRQ for PCI INT %c%s\n",
1252 			 'A' + pin - 1, msg);
1253 	}
1254 	return 0;
1255 }
1256 
1257 static void pirq_disable_irq(struct pci_dev *dev)
1258 {
1259 	if (io_apic_assign_pci_irqs && !dev->dev.power.is_prepared &&
1260 	    dev->irq) {
1261 		mp_unmap_irq(dev->irq);
1262 		dev->irq = 0;
1263 	}
1264 }
1265