xref: /linux/arch/x86/pci/irq.c (revision cc04a46f11ea046ed53e2c832ae29e4790f7e35f)
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  *  PIC Edge/Level Control Registers (ELCR) 0x4d0 & 0x4d1.
150  */
151 
152 void elcr_set_level_irq(unsigned int irq)
153 {
154 	unsigned char mask = 1 << (irq & 7);
155 	unsigned int port = 0x4d0 + (irq >> 3);
156 	unsigned char val;
157 	static u16 elcr_irq_mask;
158 
159 	if (irq >= 16 || (1 << irq) & elcr_irq_mask)
160 		return;
161 
162 	elcr_irq_mask |= (1 << irq);
163 	printk(KERN_DEBUG "PCI: setting IRQ %u as level-triggered\n", irq);
164 	val = inb(port);
165 	if (!(val & mask)) {
166 		DBG(KERN_DEBUG " -> edge");
167 		outb(val | mask, port);
168 	}
169 }
170 
171 /*
172  * Common IRQ routing practice: nibbles in config space,
173  * offset by some magic constant.
174  */
175 static unsigned int read_config_nybble(struct pci_dev *router, unsigned offset, unsigned nr)
176 {
177 	u8 x;
178 	unsigned reg = offset + (nr >> 1);
179 
180 	pci_read_config_byte(router, reg, &x);
181 	return (nr & 1) ? (x >> 4) : (x & 0xf);
182 }
183 
184 static void write_config_nybble(struct pci_dev *router, unsigned offset,
185 	unsigned nr, unsigned int val)
186 {
187 	u8 x;
188 	unsigned reg = offset + (nr >> 1);
189 
190 	pci_read_config_byte(router, reg, &x);
191 	x = (nr & 1) ? ((x & 0x0f) | (val << 4)) : ((x & 0xf0) | val);
192 	pci_write_config_byte(router, reg, x);
193 }
194 
195 /*
196  * ALI pirq entries are damn ugly, and completely undocumented.
197  * This has been figured out from pirq tables, and it's not a pretty
198  * picture.
199  */
200 static int pirq_ali_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
201 {
202 	static const unsigned char irqmap[16] = { 0, 9, 3, 10, 4, 5, 7, 6, 1, 11, 0, 12, 0, 14, 0, 15 };
203 
204 	WARN_ON_ONCE(pirq > 16);
205 	return irqmap[read_config_nybble(router, 0x48, pirq-1)];
206 }
207 
208 static int pirq_ali_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
209 {
210 	static const unsigned char irqmap[16] = { 0, 8, 0, 2, 4, 5, 7, 6, 0, 1, 3, 9, 11, 0, 13, 15 };
211 	unsigned int val = irqmap[irq];
212 
213 	WARN_ON_ONCE(pirq > 16);
214 	if (val) {
215 		write_config_nybble(router, 0x48, pirq-1, val);
216 		return 1;
217 	}
218 	return 0;
219 }
220 
221 /*
222  * The Intel PIIX4 pirq rules are fairly simple: "pirq" is
223  * just a pointer to the config space.
224  */
225 static int pirq_piix_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
226 {
227 	u8 x;
228 
229 	pci_read_config_byte(router, pirq, &x);
230 	return (x < 16) ? x : 0;
231 }
232 
233 static int pirq_piix_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
234 {
235 	pci_write_config_byte(router, pirq, irq);
236 	return 1;
237 }
238 
239 /*
240  * The VIA pirq rules are nibble-based, like ALI,
241  * but without the ugly irq number munging.
242  * However, PIRQD is in the upper instead of lower 4 bits.
243  */
244 static int pirq_via_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
245 {
246 	return read_config_nybble(router, 0x55, pirq == 4 ? 5 : pirq);
247 }
248 
249 static int pirq_via_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
250 {
251 	write_config_nybble(router, 0x55, pirq == 4 ? 5 : pirq, irq);
252 	return 1;
253 }
254 
255 /*
256  * The VIA pirq rules are nibble-based, like ALI,
257  * but without the ugly irq number munging.
258  * However, for 82C586, nibble map is different .
259  */
260 static int pirq_via586_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
261 {
262 	static const unsigned int pirqmap[5] = { 3, 2, 5, 1, 1 };
263 
264 	WARN_ON_ONCE(pirq > 5);
265 	return read_config_nybble(router, 0x55, pirqmap[pirq-1]);
266 }
267 
268 static int pirq_via586_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
269 {
270 	static const unsigned int pirqmap[5] = { 3, 2, 5, 1, 1 };
271 
272 	WARN_ON_ONCE(pirq > 5);
273 	write_config_nybble(router, 0x55, pirqmap[pirq-1], irq);
274 	return 1;
275 }
276 
277 /*
278  * ITE 8330G pirq rules are nibble-based
279  * FIXME: pirqmap may be { 1, 0, 3, 2 },
280  * 	  2+3 are both mapped to irq 9 on my system
281  */
282 static int pirq_ite_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
283 {
284 	static const unsigned char pirqmap[4] = { 1, 0, 2, 3 };
285 
286 	WARN_ON_ONCE(pirq > 4);
287 	return read_config_nybble(router, 0x43, pirqmap[pirq-1]);
288 }
289 
290 static int pirq_ite_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
291 {
292 	static const unsigned char pirqmap[4] = { 1, 0, 2, 3 };
293 
294 	WARN_ON_ONCE(pirq > 4);
295 	write_config_nybble(router, 0x43, pirqmap[pirq-1], irq);
296 	return 1;
297 }
298 
299 /*
300  * OPTI: high four bits are nibble pointer..
301  * I wonder what the low bits do?
302  */
303 static int pirq_opti_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
304 {
305 	return read_config_nybble(router, 0xb8, pirq >> 4);
306 }
307 
308 static int pirq_opti_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
309 {
310 	write_config_nybble(router, 0xb8, pirq >> 4, irq);
311 	return 1;
312 }
313 
314 /*
315  * Cyrix: nibble offset 0x5C
316  * 0x5C bits 7:4 is INTB bits 3:0 is INTA
317  * 0x5D bits 7:4 is INTD bits 3:0 is INTC
318  */
319 static int pirq_cyrix_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
320 {
321 	return read_config_nybble(router, 0x5C, (pirq-1)^1);
322 }
323 
324 static int pirq_cyrix_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
325 {
326 	write_config_nybble(router, 0x5C, (pirq-1)^1, irq);
327 	return 1;
328 }
329 
330 /*
331  *	PIRQ routing for SiS 85C503 router used in several SiS chipsets.
332  *	We have to deal with the following issues here:
333  *	- vendors have different ideas about the meaning of link values
334  *	- some onboard devices (integrated in the chipset) have special
335  *	  links and are thus routed differently (i.e. not via PCI INTA-INTD)
336  *	- different revision of the router have a different layout for
337  *	  the routing registers, particularly for the onchip devices
338  *
339  *	For all routing registers the common thing is we have one byte
340  *	per routeable link which is defined as:
341  *		 bit 7      IRQ mapping enabled (0) or disabled (1)
342  *		 bits [6:4] reserved (sometimes used for onchip devices)
343  *		 bits [3:0] IRQ to map to
344  *		     allowed: 3-7, 9-12, 14-15
345  *		     reserved: 0, 1, 2, 8, 13
346  *
347  *	The config-space registers located at 0x41/0x42/0x43/0x44 are
348  *	always used to route the normal PCI INT A/B/C/D respectively.
349  *	Apparently there are systems implementing PCI routing table using
350  *	link values 0x01-0x04 and others using 0x41-0x44 for PCI INTA..D.
351  *	We try our best to handle both link mappings.
352  *
353  *	Currently (2003-05-21) it appears most SiS chipsets follow the
354  *	definition of routing registers from the SiS-5595 southbridge.
355  *	According to the SiS 5595 datasheets the revision id's of the
356  *	router (ISA-bridge) should be 0x01 or 0xb0.
357  *
358  *	Furthermore we've also seen lspci dumps with revision 0x00 and 0xb1.
359  *	Looks like these are used in a number of SiS 5xx/6xx/7xx chipsets.
360  *	They seem to work with the current routing code. However there is
361  *	some concern because of the two USB-OHCI HCs (original SiS 5595
362  *	had only one). YMMV.
363  *
364  *	Onchip routing for router rev-id 0x01/0xb0 and probably 0x00/0xb1:
365  *
366  *	0x61:	IDEIRQ:
367  *		bits [6:5] must be written 01
368  *		bit 4 channel-select primary (0), secondary (1)
369  *
370  *	0x62:	USBIRQ:
371  *		bit 6 OHCI function disabled (0), enabled (1)
372  *
373  *	0x6a:	ACPI/SCI IRQ: bits 4-6 reserved
374  *
375  *	0x7e:	Data Acq. Module IRQ - bits 4-6 reserved
376  *
377  *	We support USBIRQ (in addition to INTA-INTD) and keep the
378  *	IDE, ACPI and DAQ routing untouched as set by the BIOS.
379  *
380  *	Currently the only reported exception is the new SiS 65x chipset
381  *	which includes the SiS 69x southbridge. Here we have the 85C503
382  *	router revision 0x04 and there are changes in the register layout
383  *	mostly related to the different USB HCs with USB 2.0 support.
384  *
385  *	Onchip routing for router rev-id 0x04 (try-and-error observation)
386  *
387  *	0x60/0x61/0x62/0x63:	1xEHCI and 3xOHCI (companion) USB-HCs
388  *				bit 6-4 are probably unused, not like 5595
389  */
390 
391 #define PIRQ_SIS_IRQ_MASK	0x0f
392 #define PIRQ_SIS_IRQ_DISABLE	0x80
393 #define PIRQ_SIS_USB_ENABLE	0x40
394 
395 static int pirq_sis_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
396 {
397 	u8 x;
398 	int reg;
399 
400 	reg = pirq;
401 	if (reg >= 0x01 && reg <= 0x04)
402 		reg += 0x40;
403 	pci_read_config_byte(router, reg, &x);
404 	return (x & PIRQ_SIS_IRQ_DISABLE) ? 0 : (x & PIRQ_SIS_IRQ_MASK);
405 }
406 
407 static int pirq_sis_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
408 {
409 	u8 x;
410 	int reg;
411 
412 	reg = pirq;
413 	if (reg >= 0x01 && reg <= 0x04)
414 		reg += 0x40;
415 	pci_read_config_byte(router, reg, &x);
416 	x &= ~(PIRQ_SIS_IRQ_MASK | PIRQ_SIS_IRQ_DISABLE);
417 	x |= irq ? irq: PIRQ_SIS_IRQ_DISABLE;
418 	pci_write_config_byte(router, reg, x);
419 	return 1;
420 }
421 
422 
423 /*
424  * VLSI: nibble offset 0x74 - educated guess due to routing table and
425  *       config space of VLSI 82C534 PCI-bridge/router (1004:0102)
426  *       Tested on HP OmniBook 800 covering PIRQ 1, 2, 4, 8 for onboard
427  *       devices, PIRQ 3 for non-pci(!) soundchip and (untested) PIRQ 6
428  *       for the busbridge to the docking station.
429  */
430 
431 static int pirq_vlsi_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
432 {
433 	WARN_ON_ONCE(pirq >= 9);
434 	if (pirq > 8) {
435 		dev_info(&dev->dev, "VLSI router PIRQ escape (%d)\n", pirq);
436 		return 0;
437 	}
438 	return read_config_nybble(router, 0x74, pirq-1);
439 }
440 
441 static int pirq_vlsi_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
442 {
443 	WARN_ON_ONCE(pirq >= 9);
444 	if (pirq > 8) {
445 		dev_info(&dev->dev, "VLSI router PIRQ escape (%d)\n", pirq);
446 		return 0;
447 	}
448 	write_config_nybble(router, 0x74, pirq-1, irq);
449 	return 1;
450 }
451 
452 /*
453  * ServerWorks: PCI interrupts mapped to system IRQ lines through Index
454  * and Redirect I/O registers (0x0c00 and 0x0c01).  The Index register
455  * format is (PCIIRQ## | 0x10), e.g.: PCIIRQ10=0x1a.  The Redirect
456  * register is a straight binary coding of desired PIC IRQ (low nibble).
457  *
458  * The 'link' value in the PIRQ table is already in the correct format
459  * for the Index register.  There are some special index values:
460  * 0x00 for ACPI (SCI), 0x01 for USB, 0x02 for IDE0, 0x04 for IDE1,
461  * and 0x03 for SMBus.
462  */
463 static int pirq_serverworks_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
464 {
465 	outb(pirq, 0xc00);
466 	return inb(0xc01) & 0xf;
467 }
468 
469 static int pirq_serverworks_set(struct pci_dev *router, struct pci_dev *dev,
470 	int pirq, int irq)
471 {
472 	outb(pirq, 0xc00);
473 	outb(irq, 0xc01);
474 	return 1;
475 }
476 
477 /* Support for AMD756 PCI IRQ Routing
478  * Jhon H. Caicedo <jhcaiced@osso.org.co>
479  * Jun/21/2001 0.2.0 Release, fixed to use "nybble" functions... (jhcaiced)
480  * Jun/19/2001 Alpha Release 0.1.0 (jhcaiced)
481  * The AMD756 pirq rules are nibble-based
482  * offset 0x56 0-3 PIRQA  4-7  PIRQB
483  * offset 0x57 0-3 PIRQC  4-7  PIRQD
484  */
485 static int pirq_amd756_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
486 {
487 	u8 irq;
488 	irq = 0;
489 	if (pirq <= 4)
490 		irq = read_config_nybble(router, 0x56, pirq - 1);
491 	dev_info(&dev->dev,
492 		 "AMD756: dev [%04x:%04x], router PIRQ %d get IRQ %d\n",
493 		 dev->vendor, dev->device, pirq, irq);
494 	return irq;
495 }
496 
497 static int pirq_amd756_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
498 {
499 	dev_info(&dev->dev,
500 		 "AMD756: dev [%04x:%04x], router PIRQ %d set IRQ %d\n",
501 		 dev->vendor, dev->device, pirq, irq);
502 	if (pirq <= 4)
503 		write_config_nybble(router, 0x56, pirq - 1, irq);
504 	return 1;
505 }
506 
507 /*
508  * PicoPower PT86C523
509  */
510 static int pirq_pico_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
511 {
512 	outb(0x10 + ((pirq - 1) >> 1), 0x24);
513 	return ((pirq - 1) & 1) ? (inb(0x26) >> 4) : (inb(0x26) & 0xf);
514 }
515 
516 static int pirq_pico_set(struct pci_dev *router, struct pci_dev *dev, int pirq,
517 			int irq)
518 {
519 	unsigned int x;
520 	outb(0x10 + ((pirq - 1) >> 1), 0x24);
521 	x = inb(0x26);
522 	x = ((pirq - 1) & 1) ? ((x & 0x0f) | (irq << 4)) : ((x & 0xf0) | (irq));
523 	outb(x, 0x26);
524 	return 1;
525 }
526 
527 #ifdef CONFIG_PCI_BIOS
528 
529 static int pirq_bios_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
530 {
531 	struct pci_dev *bridge;
532 	int pin = pci_get_interrupt_pin(dev, &bridge);
533 	return pcibios_set_irq_routing(bridge, pin - 1, irq);
534 }
535 
536 #endif
537 
538 static __init int intel_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
539 {
540 	static struct pci_device_id __initdata pirq_440gx[] = {
541 		{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443GX_0) },
542 		{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443GX_2) },
543 		{ },
544 	};
545 
546 	/* 440GX has a proprietary PIRQ router -- don't use it */
547 	if (pci_dev_present(pirq_440gx))
548 		return 0;
549 
550 	switch (device) {
551 	case PCI_DEVICE_ID_INTEL_82371FB_0:
552 	case PCI_DEVICE_ID_INTEL_82371SB_0:
553 	case PCI_DEVICE_ID_INTEL_82371AB_0:
554 	case PCI_DEVICE_ID_INTEL_82371MX:
555 	case PCI_DEVICE_ID_INTEL_82443MX_0:
556 	case PCI_DEVICE_ID_INTEL_82801AA_0:
557 	case PCI_DEVICE_ID_INTEL_82801AB_0:
558 	case PCI_DEVICE_ID_INTEL_82801BA_0:
559 	case PCI_DEVICE_ID_INTEL_82801BA_10:
560 	case PCI_DEVICE_ID_INTEL_82801CA_0:
561 	case PCI_DEVICE_ID_INTEL_82801CA_12:
562 	case PCI_DEVICE_ID_INTEL_82801DB_0:
563 	case PCI_DEVICE_ID_INTEL_82801E_0:
564 	case PCI_DEVICE_ID_INTEL_82801EB_0:
565 	case PCI_DEVICE_ID_INTEL_ESB_1:
566 	case PCI_DEVICE_ID_INTEL_ICH6_0:
567 	case PCI_DEVICE_ID_INTEL_ICH6_1:
568 	case PCI_DEVICE_ID_INTEL_ICH7_0:
569 	case PCI_DEVICE_ID_INTEL_ICH7_1:
570 	case PCI_DEVICE_ID_INTEL_ICH7_30:
571 	case PCI_DEVICE_ID_INTEL_ICH7_31:
572 	case PCI_DEVICE_ID_INTEL_TGP_LPC:
573 	case PCI_DEVICE_ID_INTEL_ESB2_0:
574 	case PCI_DEVICE_ID_INTEL_ICH8_0:
575 	case PCI_DEVICE_ID_INTEL_ICH8_1:
576 	case PCI_DEVICE_ID_INTEL_ICH8_2:
577 	case PCI_DEVICE_ID_INTEL_ICH8_3:
578 	case PCI_DEVICE_ID_INTEL_ICH8_4:
579 	case PCI_DEVICE_ID_INTEL_ICH9_0:
580 	case PCI_DEVICE_ID_INTEL_ICH9_1:
581 	case PCI_DEVICE_ID_INTEL_ICH9_2:
582 	case PCI_DEVICE_ID_INTEL_ICH9_3:
583 	case PCI_DEVICE_ID_INTEL_ICH9_4:
584 	case PCI_DEVICE_ID_INTEL_ICH9_5:
585 	case PCI_DEVICE_ID_INTEL_EP80579_0:
586 	case PCI_DEVICE_ID_INTEL_ICH10_0:
587 	case PCI_DEVICE_ID_INTEL_ICH10_1:
588 	case PCI_DEVICE_ID_INTEL_ICH10_2:
589 	case PCI_DEVICE_ID_INTEL_ICH10_3:
590 	case PCI_DEVICE_ID_INTEL_PATSBURG_LPC_0:
591 	case PCI_DEVICE_ID_INTEL_PATSBURG_LPC_1:
592 		r->name = "PIIX/ICH";
593 		r->get = pirq_piix_get;
594 		r->set = pirq_piix_set;
595 		return 1;
596 	}
597 
598 	if ((device >= PCI_DEVICE_ID_INTEL_5_3400_SERIES_LPC_MIN &&
599 	     device <= PCI_DEVICE_ID_INTEL_5_3400_SERIES_LPC_MAX)
600 	||  (device >= PCI_DEVICE_ID_INTEL_COUGARPOINT_LPC_MIN &&
601 	     device <= PCI_DEVICE_ID_INTEL_COUGARPOINT_LPC_MAX)
602 	||  (device >= PCI_DEVICE_ID_INTEL_DH89XXCC_LPC_MIN &&
603 	     device <= PCI_DEVICE_ID_INTEL_DH89XXCC_LPC_MAX)
604 	||  (device >= PCI_DEVICE_ID_INTEL_PANTHERPOINT_LPC_MIN &&
605 	     device <= PCI_DEVICE_ID_INTEL_PANTHERPOINT_LPC_MAX)) {
606 		r->name = "PIIX/ICH";
607 		r->get = pirq_piix_get;
608 		r->set = pirq_piix_set;
609 		return 1;
610 	}
611 
612 	return 0;
613 }
614 
615 static __init int via_router_probe(struct irq_router *r,
616 				struct pci_dev *router, u16 device)
617 {
618 	/* FIXME: We should move some of the quirk fixup stuff here */
619 
620 	/*
621 	 * workarounds for some buggy BIOSes
622 	 */
623 	if (device == PCI_DEVICE_ID_VIA_82C586_0) {
624 		switch (router->device) {
625 		case PCI_DEVICE_ID_VIA_82C686:
626 			/*
627 			 * Asus k7m bios wrongly reports 82C686A
628 			 * as 586-compatible
629 			 */
630 			device = PCI_DEVICE_ID_VIA_82C686;
631 			break;
632 		case PCI_DEVICE_ID_VIA_8235:
633 			/**
634 			 * Asus a7v-x bios wrongly reports 8235
635 			 * as 586-compatible
636 			 */
637 			device = PCI_DEVICE_ID_VIA_8235;
638 			break;
639 		case PCI_DEVICE_ID_VIA_8237:
640 			/**
641 			 * Asus a7v600 bios wrongly reports 8237
642 			 * as 586-compatible
643 			 */
644 			device = PCI_DEVICE_ID_VIA_8237;
645 			break;
646 		}
647 	}
648 
649 	switch (device) {
650 	case PCI_DEVICE_ID_VIA_82C586_0:
651 		r->name = "VIA";
652 		r->get = pirq_via586_get;
653 		r->set = pirq_via586_set;
654 		return 1;
655 	case PCI_DEVICE_ID_VIA_82C596:
656 	case PCI_DEVICE_ID_VIA_82C686:
657 	case PCI_DEVICE_ID_VIA_8231:
658 	case PCI_DEVICE_ID_VIA_8233A:
659 	case PCI_DEVICE_ID_VIA_8235:
660 	case PCI_DEVICE_ID_VIA_8237:
661 		/* FIXME: add new ones for 8233/5 */
662 		r->name = "VIA";
663 		r->get = pirq_via_get;
664 		r->set = pirq_via_set;
665 		return 1;
666 	}
667 	return 0;
668 }
669 
670 static __init int vlsi_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
671 {
672 	switch (device) {
673 	case PCI_DEVICE_ID_VLSI_82C534:
674 		r->name = "VLSI 82C534";
675 		r->get = pirq_vlsi_get;
676 		r->set = pirq_vlsi_set;
677 		return 1;
678 	}
679 	return 0;
680 }
681 
682 
683 static __init int serverworks_router_probe(struct irq_router *r,
684 		struct pci_dev *router, u16 device)
685 {
686 	switch (device) {
687 	case PCI_DEVICE_ID_SERVERWORKS_OSB4:
688 	case PCI_DEVICE_ID_SERVERWORKS_CSB5:
689 		r->name = "ServerWorks";
690 		r->get = pirq_serverworks_get;
691 		r->set = pirq_serverworks_set;
692 		return 1;
693 	}
694 	return 0;
695 }
696 
697 static __init int sis_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
698 {
699 	if (device != PCI_DEVICE_ID_SI_503)
700 		return 0;
701 
702 	r->name = "SIS";
703 	r->get = pirq_sis_get;
704 	r->set = pirq_sis_set;
705 	return 1;
706 }
707 
708 static __init int cyrix_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
709 {
710 	switch (device) {
711 	case PCI_DEVICE_ID_CYRIX_5520:
712 		r->name = "NatSemi";
713 		r->get = pirq_cyrix_get;
714 		r->set = pirq_cyrix_set;
715 		return 1;
716 	}
717 	return 0;
718 }
719 
720 static __init int opti_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
721 {
722 	switch (device) {
723 	case PCI_DEVICE_ID_OPTI_82C700:
724 		r->name = "OPTI";
725 		r->get = pirq_opti_get;
726 		r->set = pirq_opti_set;
727 		return 1;
728 	}
729 	return 0;
730 }
731 
732 static __init int ite_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
733 {
734 	switch (device) {
735 	case PCI_DEVICE_ID_ITE_IT8330G_0:
736 		r->name = "ITE";
737 		r->get = pirq_ite_get;
738 		r->set = pirq_ite_set;
739 		return 1;
740 	}
741 	return 0;
742 }
743 
744 static __init int ali_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
745 {
746 	switch (device) {
747 	case PCI_DEVICE_ID_AL_M1533:
748 	case PCI_DEVICE_ID_AL_M1563:
749 		r->name = "ALI";
750 		r->get = pirq_ali_get;
751 		r->set = pirq_ali_set;
752 		return 1;
753 	}
754 	return 0;
755 }
756 
757 static __init int amd_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
758 {
759 	switch (device) {
760 	case PCI_DEVICE_ID_AMD_VIPER_740B:
761 		r->name = "AMD756";
762 		break;
763 	case PCI_DEVICE_ID_AMD_VIPER_7413:
764 		r->name = "AMD766";
765 		break;
766 	case PCI_DEVICE_ID_AMD_VIPER_7443:
767 		r->name = "AMD768";
768 		break;
769 	default:
770 		return 0;
771 	}
772 	r->get = pirq_amd756_get;
773 	r->set = pirq_amd756_set;
774 	return 1;
775 }
776 
777 static __init int pico_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
778 {
779 	switch (device) {
780 	case PCI_DEVICE_ID_PICOPOWER_PT86C523:
781 		r->name = "PicoPower PT86C523";
782 		r->get = pirq_pico_get;
783 		r->set = pirq_pico_set;
784 		return 1;
785 
786 	case PCI_DEVICE_ID_PICOPOWER_PT86C523BBP:
787 		r->name = "PicoPower PT86C523 rev. BB+";
788 		r->get = pirq_pico_get;
789 		r->set = pirq_pico_set;
790 		return 1;
791 	}
792 	return 0;
793 }
794 
795 static __initdata struct irq_router_handler pirq_routers[] = {
796 	{ PCI_VENDOR_ID_INTEL, intel_router_probe },
797 	{ PCI_VENDOR_ID_AL, ali_router_probe },
798 	{ PCI_VENDOR_ID_ITE, ite_router_probe },
799 	{ PCI_VENDOR_ID_VIA, via_router_probe },
800 	{ PCI_VENDOR_ID_OPTI, opti_router_probe },
801 	{ PCI_VENDOR_ID_SI, sis_router_probe },
802 	{ PCI_VENDOR_ID_CYRIX, cyrix_router_probe },
803 	{ PCI_VENDOR_ID_VLSI, vlsi_router_probe },
804 	{ PCI_VENDOR_ID_SERVERWORKS, serverworks_router_probe },
805 	{ PCI_VENDOR_ID_AMD, amd_router_probe },
806 	{ PCI_VENDOR_ID_PICOPOWER, pico_router_probe },
807 	/* Someone with docs needs to add the ATI Radeon IGP */
808 	{ 0, NULL }
809 };
810 static struct irq_router pirq_router;
811 static struct pci_dev *pirq_router_dev;
812 
813 
814 /*
815  *	FIXME: should we have an option to say "generic for
816  *	chipset" ?
817  */
818 
819 static void __init pirq_find_router(struct irq_router *r)
820 {
821 	struct irq_routing_table *rt = pirq_table;
822 	struct irq_router_handler *h;
823 
824 #ifdef CONFIG_PCI_BIOS
825 	if (!rt->signature) {
826 		printk(KERN_INFO "PCI: Using BIOS for IRQ routing\n");
827 		r->set = pirq_bios_set;
828 		r->name = "BIOS";
829 		return;
830 	}
831 #endif
832 
833 	/* Default unless a driver reloads it */
834 	r->name = "default";
835 	r->get = NULL;
836 	r->set = NULL;
837 
838 	DBG(KERN_DEBUG "PCI: Attempting to find IRQ router for [%04x:%04x]\n",
839 	    rt->rtr_vendor, rt->rtr_device);
840 
841 	pirq_router_dev = pci_get_bus_and_slot(rt->rtr_bus, rt->rtr_devfn);
842 	if (!pirq_router_dev) {
843 		DBG(KERN_DEBUG "PCI: Interrupt router not found at "
844 			"%02x:%02x\n", rt->rtr_bus, rt->rtr_devfn);
845 		return;
846 	}
847 
848 	for (h = pirq_routers; h->vendor; h++) {
849 		/* First look for a router match */
850 		if (rt->rtr_vendor == h->vendor &&
851 			h->probe(r, pirq_router_dev, rt->rtr_device))
852 			break;
853 		/* Fall back to a device match */
854 		if (pirq_router_dev->vendor == h->vendor &&
855 			h->probe(r, pirq_router_dev, pirq_router_dev->device))
856 			break;
857 	}
858 	dev_info(&pirq_router_dev->dev, "%s IRQ router [%04x:%04x]\n",
859 		 pirq_router.name,
860 		 pirq_router_dev->vendor, pirq_router_dev->device);
861 
862 	/* The device remains referenced for the kernel lifetime */
863 }
864 
865 static struct irq_info *pirq_get_info(struct pci_dev *dev)
866 {
867 	struct irq_routing_table *rt = pirq_table;
868 	int entries = (rt->size - sizeof(struct irq_routing_table)) /
869 		sizeof(struct irq_info);
870 	struct irq_info *info;
871 
872 	for (info = rt->slots; entries--; info++)
873 		if (info->bus == dev->bus->number &&
874 			PCI_SLOT(info->devfn) == PCI_SLOT(dev->devfn))
875 			return info;
876 	return NULL;
877 }
878 
879 static int pcibios_lookup_irq(struct pci_dev *dev, int assign)
880 {
881 	u8 pin;
882 	struct irq_info *info;
883 	int i, pirq, newirq;
884 	int irq = 0;
885 	u32 mask;
886 	struct irq_router *r = &pirq_router;
887 	struct pci_dev *dev2 = NULL;
888 	char *msg = NULL;
889 
890 	/* Find IRQ pin */
891 	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
892 	if (!pin) {
893 		dev_dbg(&dev->dev, "no interrupt pin\n");
894 		return 0;
895 	}
896 
897 	if (io_apic_assign_pci_irqs)
898 		return 0;
899 
900 	/* Find IRQ routing entry */
901 
902 	if (!pirq_table)
903 		return 0;
904 
905 	info = pirq_get_info(dev);
906 	if (!info) {
907 		dev_dbg(&dev->dev, "PCI INT %c not found in routing table\n",
908 			'A' + pin - 1);
909 		return 0;
910 	}
911 	pirq = info->irq[pin - 1].link;
912 	mask = info->irq[pin - 1].bitmap;
913 	if (!pirq) {
914 		dev_dbg(&dev->dev, "PCI INT %c not routed\n", 'A' + pin - 1);
915 		return 0;
916 	}
917 	dev_dbg(&dev->dev, "PCI INT %c -> PIRQ %02x, mask %04x, excl %04x",
918 		'A' + pin - 1, pirq, mask, pirq_table->exclusive_irqs);
919 	mask &= pcibios_irq_mask;
920 
921 	/* Work around broken HP Pavilion Notebooks which assign USB to
922 	   IRQ 9 even though it is actually wired to IRQ 11 */
923 
924 	if (broken_hp_bios_irq9 && pirq == 0x59 && dev->irq == 9) {
925 		dev->irq = 11;
926 		pci_write_config_byte(dev, PCI_INTERRUPT_LINE, 11);
927 		r->set(pirq_router_dev, dev, pirq, 11);
928 	}
929 
930 	/* same for Acer Travelmate 360, but with CB and irq 11 -> 10 */
931 	if (acer_tm360_irqrouting && dev->irq == 11 &&
932 		dev->vendor == PCI_VENDOR_ID_O2) {
933 		pirq = 0x68;
934 		mask = 0x400;
935 		dev->irq = r->get(pirq_router_dev, dev, pirq);
936 		pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq);
937 	}
938 
939 	/*
940 	 * Find the best IRQ to assign: use the one
941 	 * reported by the device if possible.
942 	 */
943 	newirq = dev->irq;
944 	if (newirq && !((1 << newirq) & mask)) {
945 		if (pci_probe & PCI_USE_PIRQ_MASK)
946 			newirq = 0;
947 		else
948 			dev_warn(&dev->dev, "IRQ %d doesn't match PIRQ mask "
949 				 "%#x; try pci=usepirqmask\n", newirq, mask);
950 	}
951 	if (!newirq && assign) {
952 		for (i = 0; i < 16; i++) {
953 			if (!(mask & (1 << i)))
954 				continue;
955 			if (pirq_penalty[i] < pirq_penalty[newirq] &&
956 				can_request_irq(i, IRQF_SHARED))
957 				newirq = i;
958 		}
959 	}
960 	dev_dbg(&dev->dev, "PCI INT %c -> newirq %d", 'A' + pin - 1, newirq);
961 
962 	/* Check if it is hardcoded */
963 	if ((pirq & 0xf0) == 0xf0) {
964 		irq = pirq & 0xf;
965 		msg = "hardcoded";
966 	} else if (r->get && (irq = r->get(pirq_router_dev, dev, pirq)) && \
967 	((!(pci_probe & PCI_USE_PIRQ_MASK)) || ((1 << irq) & mask))) {
968 		msg = "found";
969 		elcr_set_level_irq(irq);
970 	} else if (newirq && r->set &&
971 		(dev->class >> 8) != PCI_CLASS_DISPLAY_VGA) {
972 		if (r->set(pirq_router_dev, dev, pirq, newirq)) {
973 			elcr_set_level_irq(newirq);
974 			msg = "assigned";
975 			irq = newirq;
976 		}
977 	}
978 
979 	if (!irq) {
980 		if (newirq && mask == (1 << newirq)) {
981 			msg = "guessed";
982 			irq = newirq;
983 		} else {
984 			dev_dbg(&dev->dev, "can't route interrupt\n");
985 			return 0;
986 		}
987 	}
988 	dev_info(&dev->dev, "%s PCI INT %c -> IRQ %d\n", msg, 'A' + pin - 1, irq);
989 
990 	/* Update IRQ for all devices with the same pirq value */
991 	for_each_pci_dev(dev2) {
992 		pci_read_config_byte(dev2, PCI_INTERRUPT_PIN, &pin);
993 		if (!pin)
994 			continue;
995 
996 		info = pirq_get_info(dev2);
997 		if (!info)
998 			continue;
999 		if (info->irq[pin - 1].link == pirq) {
1000 			/*
1001 			 * We refuse to override the dev->irq
1002 			 * information. Give a warning!
1003 			 */
1004 			if (dev2->irq && dev2->irq != irq && \
1005 			(!(pci_probe & PCI_USE_PIRQ_MASK) || \
1006 			((1 << dev2->irq) & mask))) {
1007 #ifndef CONFIG_PCI_MSI
1008 				dev_info(&dev2->dev, "IRQ routing conflict: "
1009 					 "have IRQ %d, want IRQ %d\n",
1010 					 dev2->irq, irq);
1011 #endif
1012 				continue;
1013 			}
1014 			dev2->irq = irq;
1015 			pirq_penalty[irq]++;
1016 			if (dev != dev2)
1017 				dev_info(&dev->dev, "sharing IRQ %d with %s\n",
1018 					 irq, pci_name(dev2));
1019 		}
1020 	}
1021 	return 1;
1022 }
1023 
1024 void __init pcibios_fixup_irqs(void)
1025 {
1026 	struct pci_dev *dev = NULL;
1027 	u8 pin;
1028 
1029 	DBG(KERN_DEBUG "PCI: IRQ fixup\n");
1030 	for_each_pci_dev(dev) {
1031 		/*
1032 		 * If the BIOS has set an out of range IRQ number, just
1033 		 * ignore it.  Also keep track of which IRQ's are
1034 		 * already in use.
1035 		 */
1036 		if (dev->irq >= 16) {
1037 			dev_dbg(&dev->dev, "ignoring bogus IRQ %d\n", dev->irq);
1038 			dev->irq = 0;
1039 		}
1040 		/*
1041 		 * If the IRQ is already assigned to a PCI device,
1042 		 * ignore its ISA use penalty
1043 		 */
1044 		if (pirq_penalty[dev->irq] >= 100 &&
1045 				pirq_penalty[dev->irq] < 100000)
1046 			pirq_penalty[dev->irq] = 0;
1047 		pirq_penalty[dev->irq]++;
1048 	}
1049 
1050 	if (io_apic_assign_pci_irqs)
1051 		return;
1052 
1053 	dev = NULL;
1054 	for_each_pci_dev(dev) {
1055 		pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
1056 		if (!pin)
1057 			continue;
1058 
1059 		/*
1060 		 * Still no IRQ? Try to lookup one...
1061 		 */
1062 		if (!dev->irq)
1063 			pcibios_lookup_irq(dev, 0);
1064 	}
1065 }
1066 
1067 /*
1068  * Work around broken HP Pavilion Notebooks which assign USB to
1069  * IRQ 9 even though it is actually wired to IRQ 11
1070  */
1071 static int __init fix_broken_hp_bios_irq9(const struct dmi_system_id *d)
1072 {
1073 	if (!broken_hp_bios_irq9) {
1074 		broken_hp_bios_irq9 = 1;
1075 		printk(KERN_INFO "%s detected - fixing broken IRQ routing\n",
1076 			d->ident);
1077 	}
1078 	return 0;
1079 }
1080 
1081 /*
1082  * Work around broken Acer TravelMate 360 Notebooks which assign
1083  * Cardbus to IRQ 11 even though it is actually wired to IRQ 10
1084  */
1085 static int __init fix_acer_tm360_irqrouting(const struct dmi_system_id *d)
1086 {
1087 	if (!acer_tm360_irqrouting) {
1088 		acer_tm360_irqrouting = 1;
1089 		printk(KERN_INFO "%s detected - fixing broken IRQ routing\n",
1090 			d->ident);
1091 	}
1092 	return 0;
1093 }
1094 
1095 static struct dmi_system_id __initdata pciirq_dmi_table[] = {
1096 	{
1097 		.callback = fix_broken_hp_bios_irq9,
1098 		.ident = "HP Pavilion N5400 Series Laptop",
1099 		.matches = {
1100 			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1101 			DMI_MATCH(DMI_BIOS_VERSION, "GE.M1.03"),
1102 			DMI_MATCH(DMI_PRODUCT_VERSION,
1103 				"HP Pavilion Notebook Model GE"),
1104 			DMI_MATCH(DMI_BOARD_VERSION, "OmniBook N32N-736"),
1105 		},
1106 	},
1107 	{
1108 		.callback = fix_acer_tm360_irqrouting,
1109 		.ident = "Acer TravelMate 36x Laptop",
1110 		.matches = {
1111 			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
1112 			DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 360"),
1113 		},
1114 	},
1115 	{ }
1116 };
1117 
1118 void __init pcibios_irq_init(void)
1119 {
1120 	DBG(KERN_DEBUG "PCI: IRQ init\n");
1121 
1122 	if (raw_pci_ops == NULL)
1123 		return;
1124 
1125 	dmi_check_system(pciirq_dmi_table);
1126 
1127 	pirq_table = pirq_find_routing_table();
1128 
1129 #ifdef CONFIG_PCI_BIOS
1130 	if (!pirq_table && (pci_probe & PCI_BIOS_IRQ_SCAN))
1131 		pirq_table = pcibios_get_irq_routing_table();
1132 #endif
1133 	if (pirq_table) {
1134 		pirq_peer_trick();
1135 		pirq_find_router(&pirq_router);
1136 		if (pirq_table->exclusive_irqs) {
1137 			int i;
1138 			for (i = 0; i < 16; i++)
1139 				if (!(pirq_table->exclusive_irqs & (1 << i)))
1140 					pirq_penalty[i] += 100;
1141 		}
1142 		/*
1143 		 * If we're using the I/O APIC, avoid using the PCI IRQ
1144 		 * routing table
1145 		 */
1146 		if (io_apic_assign_pci_irqs)
1147 			pirq_table = NULL;
1148 	}
1149 
1150 	x86_init.pci.fixup_irqs();
1151 
1152 	if (io_apic_assign_pci_irqs && pci_routeirq) {
1153 		struct pci_dev *dev = NULL;
1154 		/*
1155 		 * PCI IRQ routing is set up by pci_enable_device(), but we
1156 		 * also do it here in case there are still broken drivers that
1157 		 * don't use pci_enable_device().
1158 		 */
1159 		printk(KERN_INFO "PCI: Routing PCI interrupts for all devices because \"pci=routeirq\" specified\n");
1160 		for_each_pci_dev(dev)
1161 			pirq_enable_irq(dev);
1162 	}
1163 }
1164 
1165 static void pirq_penalize_isa_irq(int irq, int active)
1166 {
1167 	/*
1168 	 *  If any ISAPnP device reports an IRQ in its list of possible
1169 	 *  IRQ's, we try to avoid assigning it to PCI devices.
1170 	 */
1171 	if (irq < 16) {
1172 		if (active)
1173 			pirq_penalty[irq] += 1000;
1174 		else
1175 			pirq_penalty[irq] += 100;
1176 	}
1177 }
1178 
1179 void pcibios_penalize_isa_irq(int irq, int active)
1180 {
1181 #ifdef CONFIG_ACPI
1182 	if (!acpi_noirq)
1183 		acpi_penalize_isa_irq(irq, active);
1184 	else
1185 #endif
1186 		pirq_penalize_isa_irq(irq, active);
1187 }
1188 
1189 static int pirq_enable_irq(struct pci_dev *dev)
1190 {
1191 	u8 pin = 0;
1192 
1193 	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
1194 	if (pin && !pcibios_lookup_irq(dev, 1)) {
1195 		char *msg = "";
1196 
1197 		if (!io_apic_assign_pci_irqs && dev->irq)
1198 			return 0;
1199 
1200 		if (io_apic_assign_pci_irqs) {
1201 #ifdef CONFIG_X86_IO_APIC
1202 			struct pci_dev *temp_dev;
1203 			int irq;
1204 
1205 			if (pci_has_managed_irq(dev))
1206 				return 0;
1207 
1208 			irq = IO_APIC_get_PCI_irq_vector(dev->bus->number,
1209 						PCI_SLOT(dev->devfn), pin - 1);
1210 			/*
1211 			 * Busses behind bridges are typically not listed in the MP-table.
1212 			 * In this case we have to look up the IRQ based on the parent bus,
1213 			 * parent slot, and pin number. The SMP code detects such bridged
1214 			 * busses itself so we should get into this branch reliably.
1215 			 */
1216 			temp_dev = dev;
1217 			while (irq < 0 && dev->bus->parent) { /* go back to the bridge */
1218 				struct pci_dev *bridge = dev->bus->self;
1219 
1220 				pin = pci_swizzle_interrupt_pin(dev, pin);
1221 				irq = IO_APIC_get_PCI_irq_vector(bridge->bus->number,
1222 						PCI_SLOT(bridge->devfn),
1223 						pin - 1);
1224 				if (irq >= 0)
1225 					dev_warn(&dev->dev, "using bridge %s "
1226 						 "INT %c to get IRQ %d\n",
1227 						 pci_name(bridge), 'A' + pin - 1,
1228 						 irq);
1229 				dev = bridge;
1230 			}
1231 			dev = temp_dev;
1232 			if (irq >= 0) {
1233 				pci_set_managed_irq(dev, irq);
1234 				dev_info(&dev->dev, "PCI->APIC IRQ transform: "
1235 					 "INT %c -> IRQ %d\n", 'A' + pin - 1, irq);
1236 				return 0;
1237 			} else
1238 				msg = "; probably buggy MP table";
1239 #endif
1240 		} else if (pci_probe & PCI_BIOS_IRQ_SCAN)
1241 			msg = "";
1242 		else
1243 			msg = "; please try using pci=biosirq";
1244 
1245 		/*
1246 		 * With IDE legacy devices the IRQ lookup failure is not
1247 		 * a problem..
1248 		 */
1249 		if (dev->class >> 8 == PCI_CLASS_STORAGE_IDE &&
1250 				!(dev->class & 0x5))
1251 			return 0;
1252 
1253 		dev_warn(&dev->dev, "can't find IRQ for PCI INT %c%s\n",
1254 			 'A' + pin - 1, msg);
1255 	}
1256 	return 0;
1257 }
1258 
1259 static void pirq_disable_irq(struct pci_dev *dev)
1260 {
1261 	if (io_apic_assign_pci_irqs && pci_has_managed_irq(dev)) {
1262 		mp_unmap_irq(dev->irq);
1263 		pci_reset_managed_irq(dev);
1264 	}
1265 }
1266