xref: /openbmc/linux/arch/x86/pci/irq.c (revision 8dda2eac)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *	Low-Level PCI Support for PC -- Routing of Interrupts
4  *
5  *	(c) 1999--2000 Martin Mares <mj@ucw.cz>
6  */
7 
8 #include <linux/types.h>
9 #include <linux/kernel.h>
10 #include <linux/pci.h>
11 #include <linux/init.h>
12 #include <linux/interrupt.h>
13 #include <linux/dmi.h>
14 #include <linux/io.h>
15 #include <linux/smp.h>
16 #include <asm/io_apic.h>
17 #include <linux/irq.h>
18 #include <linux/acpi.h>
19 #include <asm/pci_x86.h>
20 
21 #define PIRQ_SIGNATURE	(('$' << 0) + ('P' << 8) + ('I' << 16) + ('R' << 24))
22 #define PIRQ_VERSION 0x0100
23 
24 static int broken_hp_bios_irq9;
25 static int acer_tm360_irqrouting;
26 
27 static struct irq_routing_table *pirq_table;
28 
29 static int pirq_enable_irq(struct pci_dev *dev);
30 static void pirq_disable_irq(struct pci_dev *dev);
31 
32 /*
33  * Never use: 0, 1, 2 (timer, keyboard, and cascade)
34  * Avoid using: 13, 14 and 15 (FP error and IDE).
35  * Penalize: 3, 4, 6, 7, 12 (known ISA uses: serial, floppy, parallel and mouse)
36  */
37 unsigned int pcibios_irq_mask = 0xfff8;
38 
39 static int pirq_penalty[16] = {
40 	1000000, 1000000, 1000000, 1000, 1000, 0, 1000, 1000,
41 	0, 0, 0, 0, 1000, 100000, 100000, 100000
42 };
43 
44 struct irq_router {
45 	char *name;
46 	u16 vendor, device;
47 	int (*get)(struct pci_dev *router, struct pci_dev *dev, int pirq);
48 	int (*set)(struct pci_dev *router, struct pci_dev *dev, int pirq,
49 		int new);
50 };
51 
52 struct irq_router_handler {
53 	u16 vendor;
54 	int (*probe)(struct irq_router *r, struct pci_dev *router, u16 device);
55 };
56 
57 int (*pcibios_enable_irq)(struct pci_dev *dev) = pirq_enable_irq;
58 void (*pcibios_disable_irq)(struct pci_dev *dev) = pirq_disable_irq;
59 
60 /*
61  *  Check passed address for the PCI IRQ Routing Table signature
62  *  and perform checksum verification.
63  */
64 
65 static inline struct irq_routing_table *pirq_check_routing_table(u8 *addr)
66 {
67 	struct irq_routing_table *rt;
68 	int i;
69 	u8 sum;
70 
71 	rt = (struct irq_routing_table *) addr;
72 	if (rt->signature != PIRQ_SIGNATURE ||
73 	    rt->version != PIRQ_VERSION ||
74 	    rt->size % 16 ||
75 	    rt->size < sizeof(struct irq_routing_table))
76 		return NULL;
77 	sum = 0;
78 	for (i = 0; i < rt->size; i++)
79 		sum += addr[i];
80 	if (!sum) {
81 		DBG(KERN_DEBUG "PCI: Interrupt Routing Table found at 0x%p\n",
82 			rt);
83 		return rt;
84 	}
85 	return NULL;
86 }
87 
88 
89 
90 /*
91  *  Search 0xf0000 -- 0xfffff for the PCI IRQ Routing Table.
92  */
93 
94 static struct irq_routing_table * __init pirq_find_routing_table(void)
95 {
96 	u8 *addr;
97 	struct irq_routing_table *rt;
98 
99 	if (pirq_table_addr) {
100 		rt = pirq_check_routing_table((u8 *) __va(pirq_table_addr));
101 		if (rt)
102 			return rt;
103 		printk(KERN_WARNING "PCI: PIRQ table NOT found at pirqaddr\n");
104 	}
105 	for (addr = (u8 *) __va(0xf0000); addr < (u8 *) __va(0x100000); addr += 16) {
106 		rt = pirq_check_routing_table(addr);
107 		if (rt)
108 			return rt;
109 	}
110 	return NULL;
111 }
112 
113 /*
114  *  If we have a IRQ routing table, use it to search for peer host
115  *  bridges.  It's a gross hack, but since there are no other known
116  *  ways how to get a list of buses, we have to go this way.
117  */
118 
119 static void __init pirq_peer_trick(void)
120 {
121 	struct irq_routing_table *rt = pirq_table;
122 	u8 busmap[256];
123 	int i;
124 	struct irq_info *e;
125 
126 	memset(busmap, 0, sizeof(busmap));
127 	for (i = 0; i < (rt->size - sizeof(struct irq_routing_table)) / sizeof(struct irq_info); i++) {
128 		e = &rt->slots[i];
129 #ifdef DEBUG
130 		{
131 			int j;
132 			DBG(KERN_DEBUG "%02x:%02x slot=%02x", e->bus, e->devfn/8, e->slot);
133 			for (j = 0; j < 4; j++)
134 				DBG(" %d:%02x/%04x", j, e->irq[j].link, e->irq[j].bitmap);
135 			DBG("\n");
136 		}
137 #endif
138 		busmap[e->bus] = 1;
139 	}
140 	for (i = 1; i < 256; i++) {
141 		if (!busmap[i] || pci_find_bus(0, i))
142 			continue;
143 		pcibios_scan_root(i);
144 	}
145 	pcibios_last_bus = -1;
146 }
147 
148 /*
149  *  Code for querying and setting of IRQ routes on various interrupt routers.
150  *  PIC Edge/Level Control Registers (ELCR) 0x4d0 & 0x4d1.
151  */
152 
153 void elcr_set_level_irq(unsigned int irq)
154 {
155 	unsigned char mask = 1 << (irq & 7);
156 	unsigned int port = 0x4d0 + (irq >> 3);
157 	unsigned char val;
158 	static u16 elcr_irq_mask;
159 
160 	if (irq >= 16 || (1 << irq) & elcr_irq_mask)
161 		return;
162 
163 	elcr_irq_mask |= (1 << irq);
164 	printk(KERN_DEBUG "PCI: setting IRQ %u as level-triggered\n", irq);
165 	val = inb(port);
166 	if (!(val & mask)) {
167 		DBG(KERN_DEBUG " -> edge");
168 		outb(val | mask, port);
169 	}
170 }
171 
172 /*
173  * Common IRQ routing practice: nibbles in config space,
174  * offset by some magic constant.
175  */
176 static unsigned int read_config_nybble(struct pci_dev *router, unsigned offset, unsigned nr)
177 {
178 	u8 x;
179 	unsigned reg = offset + (nr >> 1);
180 
181 	pci_read_config_byte(router, reg, &x);
182 	return (nr & 1) ? (x >> 4) : (x & 0xf);
183 }
184 
185 static void write_config_nybble(struct pci_dev *router, unsigned offset,
186 	unsigned nr, unsigned int val)
187 {
188 	u8 x;
189 	unsigned reg = offset + (nr >> 1);
190 
191 	pci_read_config_byte(router, reg, &x);
192 	x = (nr & 1) ? ((x & 0x0f) | (val << 4)) : ((x & 0xf0) | val);
193 	pci_write_config_byte(router, reg, x);
194 }
195 
196 /*
197  * ALI pirq entries are damn ugly, and completely undocumented.
198  * This has been figured out from pirq tables, and it's not a pretty
199  * picture.
200  */
201 static int pirq_ali_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
202 {
203 	static const unsigned char irqmap[16] = { 0, 9, 3, 10, 4, 5, 7, 6, 1, 11, 0, 12, 0, 14, 0, 15 };
204 
205 	WARN_ON_ONCE(pirq > 16);
206 	return irqmap[read_config_nybble(router, 0x48, pirq-1)];
207 }
208 
209 static int pirq_ali_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
210 {
211 	static const unsigned char irqmap[16] = { 0, 8, 0, 2, 4, 5, 7, 6, 0, 1, 3, 9, 11, 0, 13, 15 };
212 	unsigned int val = irqmap[irq];
213 
214 	WARN_ON_ONCE(pirq > 16);
215 	if (val) {
216 		write_config_nybble(router, 0x48, pirq-1, val);
217 		return 1;
218 	}
219 	return 0;
220 }
221 
222 /*
223  * The Intel PIIX4 pirq rules are fairly simple: "pirq" is
224  * just a pointer to the config space.
225  */
226 static int pirq_piix_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
227 {
228 	u8 x;
229 
230 	pci_read_config_byte(router, pirq, &x);
231 	return (x < 16) ? x : 0;
232 }
233 
234 static int pirq_piix_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
235 {
236 	pci_write_config_byte(router, pirq, irq);
237 	return 1;
238 }
239 
240 /*
241  * The VIA pirq rules are nibble-based, like ALI,
242  * but without the ugly irq number munging.
243  * However, PIRQD is in the upper instead of lower 4 bits.
244  */
245 static int pirq_via_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
246 {
247 	return read_config_nybble(router, 0x55, pirq == 4 ? 5 : pirq);
248 }
249 
250 static int pirq_via_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
251 {
252 	write_config_nybble(router, 0x55, pirq == 4 ? 5 : pirq, irq);
253 	return 1;
254 }
255 
256 /*
257  * The VIA pirq rules are nibble-based, like ALI,
258  * but without the ugly irq number munging.
259  * However, for 82C586, nibble map is different .
260  */
261 static int pirq_via586_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
262 {
263 	static const unsigned int pirqmap[5] = { 3, 2, 5, 1, 1 };
264 
265 	WARN_ON_ONCE(pirq > 5);
266 	return read_config_nybble(router, 0x55, pirqmap[pirq-1]);
267 }
268 
269 static int pirq_via586_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
270 {
271 	static const unsigned int pirqmap[5] = { 3, 2, 5, 1, 1 };
272 
273 	WARN_ON_ONCE(pirq > 5);
274 	write_config_nybble(router, 0x55, pirqmap[pirq-1], irq);
275 	return 1;
276 }
277 
278 /*
279  * ITE 8330G pirq rules are nibble-based
280  * FIXME: pirqmap may be { 1, 0, 3, 2 },
281  * 	  2+3 are both mapped to irq 9 on my system
282  */
283 static int pirq_ite_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
284 {
285 	static const unsigned char pirqmap[4] = { 1, 0, 2, 3 };
286 
287 	WARN_ON_ONCE(pirq > 4);
288 	return read_config_nybble(router, 0x43, pirqmap[pirq-1]);
289 }
290 
291 static int pirq_ite_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
292 {
293 	static const unsigned char pirqmap[4] = { 1, 0, 2, 3 };
294 
295 	WARN_ON_ONCE(pirq > 4);
296 	write_config_nybble(router, 0x43, pirqmap[pirq-1], irq);
297 	return 1;
298 }
299 
300 /*
301  * OPTI: high four bits are nibble pointer..
302  * I wonder what the low bits do?
303  */
304 static int pirq_opti_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
305 {
306 	return read_config_nybble(router, 0xb8, pirq >> 4);
307 }
308 
309 static int pirq_opti_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
310 {
311 	write_config_nybble(router, 0xb8, pirq >> 4, irq);
312 	return 1;
313 }
314 
315 /*
316  * Cyrix: nibble offset 0x5C
317  * 0x5C bits 7:4 is INTB bits 3:0 is INTA
318  * 0x5D bits 7:4 is INTD bits 3:0 is INTC
319  */
320 static int pirq_cyrix_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
321 {
322 	return read_config_nybble(router, 0x5C, (pirq-1)^1);
323 }
324 
325 static int pirq_cyrix_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
326 {
327 	write_config_nybble(router, 0x5C, (pirq-1)^1, irq);
328 	return 1;
329 }
330 
331 /*
332  *	PIRQ routing for SiS 85C503 router used in several SiS chipsets.
333  *	We have to deal with the following issues here:
334  *	- vendors have different ideas about the meaning of link values
335  *	- some onboard devices (integrated in the chipset) have special
336  *	  links and are thus routed differently (i.e. not via PCI INTA-INTD)
337  *	- different revision of the router have a different layout for
338  *	  the routing registers, particularly for the onchip devices
339  *
340  *	For all routing registers the common thing is we have one byte
341  *	per routeable link which is defined as:
342  *		 bit 7      IRQ mapping enabled (0) or disabled (1)
343  *		 bits [6:4] reserved (sometimes used for onchip devices)
344  *		 bits [3:0] IRQ to map to
345  *		     allowed: 3-7, 9-12, 14-15
346  *		     reserved: 0, 1, 2, 8, 13
347  *
348  *	The config-space registers located at 0x41/0x42/0x43/0x44 are
349  *	always used to route the normal PCI INT A/B/C/D respectively.
350  *	Apparently there are systems implementing PCI routing table using
351  *	link values 0x01-0x04 and others using 0x41-0x44 for PCI INTA..D.
352  *	We try our best to handle both link mappings.
353  *
354  *	Currently (2003-05-21) it appears most SiS chipsets follow the
355  *	definition of routing registers from the SiS-5595 southbridge.
356  *	According to the SiS 5595 datasheets the revision id's of the
357  *	router (ISA-bridge) should be 0x01 or 0xb0.
358  *
359  *	Furthermore we've also seen lspci dumps with revision 0x00 and 0xb1.
360  *	Looks like these are used in a number of SiS 5xx/6xx/7xx chipsets.
361  *	They seem to work with the current routing code. However there is
362  *	some concern because of the two USB-OHCI HCs (original SiS 5595
363  *	had only one). YMMV.
364  *
365  *	Onchip routing for router rev-id 0x01/0xb0 and probably 0x00/0xb1:
366  *
367  *	0x61:	IDEIRQ:
368  *		bits [6:5] must be written 01
369  *		bit 4 channel-select primary (0), secondary (1)
370  *
371  *	0x62:	USBIRQ:
372  *		bit 6 OHCI function disabled (0), enabled (1)
373  *
374  *	0x6a:	ACPI/SCI IRQ: bits 4-6 reserved
375  *
376  *	0x7e:	Data Acq. Module IRQ - bits 4-6 reserved
377  *
378  *	We support USBIRQ (in addition to INTA-INTD) and keep the
379  *	IDE, ACPI and DAQ routing untouched as set by the BIOS.
380  *
381  *	Currently the only reported exception is the new SiS 65x chipset
382  *	which includes the SiS 69x southbridge. Here we have the 85C503
383  *	router revision 0x04 and there are changes in the register layout
384  *	mostly related to the different USB HCs with USB 2.0 support.
385  *
386  *	Onchip routing for router rev-id 0x04 (try-and-error observation)
387  *
388  *	0x60/0x61/0x62/0x63:	1xEHCI and 3xOHCI (companion) USB-HCs
389  *				bit 6-4 are probably unused, not like 5595
390  */
391 
392 #define PIRQ_SIS_IRQ_MASK	0x0f
393 #define PIRQ_SIS_IRQ_DISABLE	0x80
394 #define PIRQ_SIS_USB_ENABLE	0x40
395 
396 static int pirq_sis_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
397 {
398 	u8 x;
399 	int reg;
400 
401 	reg = pirq;
402 	if (reg >= 0x01 && reg <= 0x04)
403 		reg += 0x40;
404 	pci_read_config_byte(router, reg, &x);
405 	return (x & PIRQ_SIS_IRQ_DISABLE) ? 0 : (x & PIRQ_SIS_IRQ_MASK);
406 }
407 
408 static int pirq_sis_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
409 {
410 	u8 x;
411 	int reg;
412 
413 	reg = pirq;
414 	if (reg >= 0x01 && reg <= 0x04)
415 		reg += 0x40;
416 	pci_read_config_byte(router, reg, &x);
417 	x &= ~(PIRQ_SIS_IRQ_MASK | PIRQ_SIS_IRQ_DISABLE);
418 	x |= irq ? irq: PIRQ_SIS_IRQ_DISABLE;
419 	pci_write_config_byte(router, reg, x);
420 	return 1;
421 }
422 
423 
424 /*
425  * VLSI: nibble offset 0x74 - educated guess due to routing table and
426  *       config space of VLSI 82C534 PCI-bridge/router (1004:0102)
427  *       Tested on HP OmniBook 800 covering PIRQ 1, 2, 4, 8 for onboard
428  *       devices, PIRQ 3 for non-pci(!) soundchip and (untested) PIRQ 6
429  *       for the busbridge to the docking station.
430  */
431 
432 static int pirq_vlsi_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
433 {
434 	WARN_ON_ONCE(pirq >= 9);
435 	if (pirq > 8) {
436 		dev_info(&dev->dev, "VLSI router PIRQ escape (%d)\n", pirq);
437 		return 0;
438 	}
439 	return read_config_nybble(router, 0x74, pirq-1);
440 }
441 
442 static int pirq_vlsi_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
443 {
444 	WARN_ON_ONCE(pirq >= 9);
445 	if (pirq > 8) {
446 		dev_info(&dev->dev, "VLSI router PIRQ escape (%d)\n", pirq);
447 		return 0;
448 	}
449 	write_config_nybble(router, 0x74, pirq-1, irq);
450 	return 1;
451 }
452 
453 /*
454  * ServerWorks: PCI interrupts mapped to system IRQ lines through Index
455  * and Redirect I/O registers (0x0c00 and 0x0c01).  The Index register
456  * format is (PCIIRQ## | 0x10), e.g.: PCIIRQ10=0x1a.  The Redirect
457  * register is a straight binary coding of desired PIC IRQ (low nibble).
458  *
459  * The 'link' value in the PIRQ table is already in the correct format
460  * for the Index register.  There are some special index values:
461  * 0x00 for ACPI (SCI), 0x01 for USB, 0x02 for IDE0, 0x04 for IDE1,
462  * and 0x03 for SMBus.
463  */
464 static int pirq_serverworks_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
465 {
466 	outb(pirq, 0xc00);
467 	return inb(0xc01) & 0xf;
468 }
469 
470 static int pirq_serverworks_set(struct pci_dev *router, struct pci_dev *dev,
471 	int pirq, int irq)
472 {
473 	outb(pirq, 0xc00);
474 	outb(irq, 0xc01);
475 	return 1;
476 }
477 
478 /* Support for AMD756 PCI IRQ Routing
479  * Jhon H. Caicedo <jhcaiced@osso.org.co>
480  * Jun/21/2001 0.2.0 Release, fixed to use "nybble" functions... (jhcaiced)
481  * Jun/19/2001 Alpha Release 0.1.0 (jhcaiced)
482  * The AMD756 pirq rules are nibble-based
483  * offset 0x56 0-3 PIRQA  4-7  PIRQB
484  * offset 0x57 0-3 PIRQC  4-7  PIRQD
485  */
486 static int pirq_amd756_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
487 {
488 	u8 irq;
489 	irq = 0;
490 	if (pirq <= 4)
491 		irq = read_config_nybble(router, 0x56, pirq - 1);
492 	dev_info(&dev->dev,
493 		 "AMD756: dev [%04x:%04x], router PIRQ %d get IRQ %d\n",
494 		 dev->vendor, dev->device, pirq, irq);
495 	return irq;
496 }
497 
498 static int pirq_amd756_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
499 {
500 	dev_info(&dev->dev,
501 		 "AMD756: dev [%04x:%04x], router PIRQ %d set IRQ %d\n",
502 		 dev->vendor, dev->device, pirq, irq);
503 	if (pirq <= 4)
504 		write_config_nybble(router, 0x56, pirq - 1, irq);
505 	return 1;
506 }
507 
508 /*
509  * PicoPower PT86C523
510  */
511 static int pirq_pico_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
512 {
513 	outb(0x10 + ((pirq - 1) >> 1), 0x24);
514 	return ((pirq - 1) & 1) ? (inb(0x26) >> 4) : (inb(0x26) & 0xf);
515 }
516 
517 static int pirq_pico_set(struct pci_dev *router, struct pci_dev *dev, int pirq,
518 			int irq)
519 {
520 	unsigned int x;
521 	outb(0x10 + ((pirq - 1) >> 1), 0x24);
522 	x = inb(0x26);
523 	x = ((pirq - 1) & 1) ? ((x & 0x0f) | (irq << 4)) : ((x & 0xf0) | (irq));
524 	outb(x, 0x26);
525 	return 1;
526 }
527 
528 #ifdef CONFIG_PCI_BIOS
529 
530 static int pirq_bios_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
531 {
532 	struct pci_dev *bridge;
533 	int pin = pci_get_interrupt_pin(dev, &bridge);
534 	return pcibios_set_irq_routing(bridge, pin - 1, irq);
535 }
536 
537 #endif
538 
539 static __init int intel_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
540 {
541 	static struct pci_device_id __initdata pirq_440gx[] = {
542 		{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443GX_0) },
543 		{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443GX_2) },
544 		{ },
545 	};
546 
547 	/* 440GX has a proprietary PIRQ router -- don't use it */
548 	if (pci_dev_present(pirq_440gx))
549 		return 0;
550 
551 	switch (device) {
552 	case PCI_DEVICE_ID_INTEL_82371FB_0:
553 	case PCI_DEVICE_ID_INTEL_82371SB_0:
554 	case PCI_DEVICE_ID_INTEL_82371AB_0:
555 	case PCI_DEVICE_ID_INTEL_82371MX:
556 	case PCI_DEVICE_ID_INTEL_82443MX_0:
557 	case PCI_DEVICE_ID_INTEL_82801AA_0:
558 	case PCI_DEVICE_ID_INTEL_82801AB_0:
559 	case PCI_DEVICE_ID_INTEL_82801BA_0:
560 	case PCI_DEVICE_ID_INTEL_82801BA_10:
561 	case PCI_DEVICE_ID_INTEL_82801CA_0:
562 	case PCI_DEVICE_ID_INTEL_82801CA_12:
563 	case PCI_DEVICE_ID_INTEL_82801DB_0:
564 	case PCI_DEVICE_ID_INTEL_82801E_0:
565 	case PCI_DEVICE_ID_INTEL_82801EB_0:
566 	case PCI_DEVICE_ID_INTEL_ESB_1:
567 	case PCI_DEVICE_ID_INTEL_ICH6_0:
568 	case PCI_DEVICE_ID_INTEL_ICH6_1:
569 	case PCI_DEVICE_ID_INTEL_ICH7_0:
570 	case PCI_DEVICE_ID_INTEL_ICH7_1:
571 	case PCI_DEVICE_ID_INTEL_ICH7_30:
572 	case PCI_DEVICE_ID_INTEL_ICH7_31:
573 	case PCI_DEVICE_ID_INTEL_TGP_LPC:
574 	case PCI_DEVICE_ID_INTEL_ESB2_0:
575 	case PCI_DEVICE_ID_INTEL_ICH8_0:
576 	case PCI_DEVICE_ID_INTEL_ICH8_1:
577 	case PCI_DEVICE_ID_INTEL_ICH8_2:
578 	case PCI_DEVICE_ID_INTEL_ICH8_3:
579 	case PCI_DEVICE_ID_INTEL_ICH8_4:
580 	case PCI_DEVICE_ID_INTEL_ICH9_0:
581 	case PCI_DEVICE_ID_INTEL_ICH9_1:
582 	case PCI_DEVICE_ID_INTEL_ICH9_2:
583 	case PCI_DEVICE_ID_INTEL_ICH9_3:
584 	case PCI_DEVICE_ID_INTEL_ICH9_4:
585 	case PCI_DEVICE_ID_INTEL_ICH9_5:
586 	case PCI_DEVICE_ID_INTEL_EP80579_0:
587 	case PCI_DEVICE_ID_INTEL_ICH10_0:
588 	case PCI_DEVICE_ID_INTEL_ICH10_1:
589 	case PCI_DEVICE_ID_INTEL_ICH10_2:
590 	case PCI_DEVICE_ID_INTEL_ICH10_3:
591 	case PCI_DEVICE_ID_INTEL_PATSBURG_LPC_0:
592 	case PCI_DEVICE_ID_INTEL_PATSBURG_LPC_1:
593 		r->name = "PIIX/ICH";
594 		r->get = pirq_piix_get;
595 		r->set = pirq_piix_set;
596 		return 1;
597 	}
598 
599 	if ((device >= PCI_DEVICE_ID_INTEL_5_3400_SERIES_LPC_MIN &&
600 	     device <= PCI_DEVICE_ID_INTEL_5_3400_SERIES_LPC_MAX)
601 	||  (device >= PCI_DEVICE_ID_INTEL_COUGARPOINT_LPC_MIN &&
602 	     device <= PCI_DEVICE_ID_INTEL_COUGARPOINT_LPC_MAX)
603 	||  (device >= PCI_DEVICE_ID_INTEL_DH89XXCC_LPC_MIN &&
604 	     device <= PCI_DEVICE_ID_INTEL_DH89XXCC_LPC_MAX)
605 	||  (device >= PCI_DEVICE_ID_INTEL_PANTHERPOINT_LPC_MIN &&
606 	     device <= PCI_DEVICE_ID_INTEL_PANTHERPOINT_LPC_MAX)) {
607 		r->name = "PIIX/ICH";
608 		r->get = pirq_piix_get;
609 		r->set = pirq_piix_set;
610 		return 1;
611 	}
612 
613 	return 0;
614 }
615 
616 static __init int via_router_probe(struct irq_router *r,
617 				struct pci_dev *router, u16 device)
618 {
619 	/* FIXME: We should move some of the quirk fixup stuff here */
620 
621 	/*
622 	 * workarounds for some buggy BIOSes
623 	 */
624 	if (device == PCI_DEVICE_ID_VIA_82C586_0) {
625 		switch (router->device) {
626 		case PCI_DEVICE_ID_VIA_82C686:
627 			/*
628 			 * Asus k7m bios wrongly reports 82C686A
629 			 * as 586-compatible
630 			 */
631 			device = PCI_DEVICE_ID_VIA_82C686;
632 			break;
633 		case PCI_DEVICE_ID_VIA_8235:
634 			/**
635 			 * Asus a7v-x bios wrongly reports 8235
636 			 * as 586-compatible
637 			 */
638 			device = PCI_DEVICE_ID_VIA_8235;
639 			break;
640 		case PCI_DEVICE_ID_VIA_8237:
641 			/**
642 			 * Asus a7v600 bios wrongly reports 8237
643 			 * as 586-compatible
644 			 */
645 			device = PCI_DEVICE_ID_VIA_8237;
646 			break;
647 		}
648 	}
649 
650 	switch (device) {
651 	case PCI_DEVICE_ID_VIA_82C586_0:
652 		r->name = "VIA";
653 		r->get = pirq_via586_get;
654 		r->set = pirq_via586_set;
655 		return 1;
656 	case PCI_DEVICE_ID_VIA_82C596:
657 	case PCI_DEVICE_ID_VIA_82C686:
658 	case PCI_DEVICE_ID_VIA_8231:
659 	case PCI_DEVICE_ID_VIA_8233A:
660 	case PCI_DEVICE_ID_VIA_8235:
661 	case PCI_DEVICE_ID_VIA_8237:
662 		/* FIXME: add new ones for 8233/5 */
663 		r->name = "VIA";
664 		r->get = pirq_via_get;
665 		r->set = pirq_via_set;
666 		return 1;
667 	}
668 	return 0;
669 }
670 
671 static __init int vlsi_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
672 {
673 	switch (device) {
674 	case PCI_DEVICE_ID_VLSI_82C534:
675 		r->name = "VLSI 82C534";
676 		r->get = pirq_vlsi_get;
677 		r->set = pirq_vlsi_set;
678 		return 1;
679 	}
680 	return 0;
681 }
682 
683 
684 static __init int serverworks_router_probe(struct irq_router *r,
685 		struct pci_dev *router, u16 device)
686 {
687 	switch (device) {
688 	case PCI_DEVICE_ID_SERVERWORKS_OSB4:
689 	case PCI_DEVICE_ID_SERVERWORKS_CSB5:
690 		r->name = "ServerWorks";
691 		r->get = pirq_serverworks_get;
692 		r->set = pirq_serverworks_set;
693 		return 1;
694 	}
695 	return 0;
696 }
697 
698 static __init int sis_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
699 {
700 	if (device != PCI_DEVICE_ID_SI_503)
701 		return 0;
702 
703 	r->name = "SIS";
704 	r->get = pirq_sis_get;
705 	r->set = pirq_sis_set;
706 	return 1;
707 }
708 
709 static __init int cyrix_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
710 {
711 	switch (device) {
712 	case PCI_DEVICE_ID_CYRIX_5520:
713 		r->name = "NatSemi";
714 		r->get = pirq_cyrix_get;
715 		r->set = pirq_cyrix_set;
716 		return 1;
717 	}
718 	return 0;
719 }
720 
721 static __init int opti_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
722 {
723 	switch (device) {
724 	case PCI_DEVICE_ID_OPTI_82C700:
725 		r->name = "OPTI";
726 		r->get = pirq_opti_get;
727 		r->set = pirq_opti_set;
728 		return 1;
729 	}
730 	return 0;
731 }
732 
733 static __init int ite_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
734 {
735 	switch (device) {
736 	case PCI_DEVICE_ID_ITE_IT8330G_0:
737 		r->name = "ITE";
738 		r->get = pirq_ite_get;
739 		r->set = pirq_ite_set;
740 		return 1;
741 	}
742 	return 0;
743 }
744 
745 static __init int ali_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
746 {
747 	switch (device) {
748 	case PCI_DEVICE_ID_AL_M1533:
749 	case PCI_DEVICE_ID_AL_M1563:
750 		r->name = "ALI";
751 		r->get = pirq_ali_get;
752 		r->set = pirq_ali_set;
753 		return 1;
754 	}
755 	return 0;
756 }
757 
758 static __init int amd_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
759 {
760 	switch (device) {
761 	case PCI_DEVICE_ID_AMD_VIPER_740B:
762 		r->name = "AMD756";
763 		break;
764 	case PCI_DEVICE_ID_AMD_VIPER_7413:
765 		r->name = "AMD766";
766 		break;
767 	case PCI_DEVICE_ID_AMD_VIPER_7443:
768 		r->name = "AMD768";
769 		break;
770 	default:
771 		return 0;
772 	}
773 	r->get = pirq_amd756_get;
774 	r->set = pirq_amd756_set;
775 	return 1;
776 }
777 
778 static __init int pico_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
779 {
780 	switch (device) {
781 	case PCI_DEVICE_ID_PICOPOWER_PT86C523:
782 		r->name = "PicoPower PT86C523";
783 		r->get = pirq_pico_get;
784 		r->set = pirq_pico_set;
785 		return 1;
786 
787 	case PCI_DEVICE_ID_PICOPOWER_PT86C523BBP:
788 		r->name = "PicoPower PT86C523 rev. BB+";
789 		r->get = pirq_pico_get;
790 		r->set = pirq_pico_set;
791 		return 1;
792 	}
793 	return 0;
794 }
795 
796 static __initdata struct irq_router_handler pirq_routers[] = {
797 	{ PCI_VENDOR_ID_INTEL, intel_router_probe },
798 	{ PCI_VENDOR_ID_AL, ali_router_probe },
799 	{ PCI_VENDOR_ID_ITE, ite_router_probe },
800 	{ PCI_VENDOR_ID_VIA, via_router_probe },
801 	{ PCI_VENDOR_ID_OPTI, opti_router_probe },
802 	{ PCI_VENDOR_ID_SI, sis_router_probe },
803 	{ PCI_VENDOR_ID_CYRIX, cyrix_router_probe },
804 	{ PCI_VENDOR_ID_VLSI, vlsi_router_probe },
805 	{ PCI_VENDOR_ID_SERVERWORKS, serverworks_router_probe },
806 	{ PCI_VENDOR_ID_AMD, amd_router_probe },
807 	{ PCI_VENDOR_ID_PICOPOWER, pico_router_probe },
808 	/* Someone with docs needs to add the ATI Radeon IGP */
809 	{ 0, NULL }
810 };
811 static struct irq_router pirq_router;
812 static struct pci_dev *pirq_router_dev;
813 
814 
815 /*
816  *	FIXME: should we have an option to say "generic for
817  *	chipset" ?
818  */
819 
820 static void __init pirq_find_router(struct irq_router *r)
821 {
822 	struct irq_routing_table *rt = pirq_table;
823 	struct irq_router_handler *h;
824 
825 #ifdef CONFIG_PCI_BIOS
826 	if (!rt->signature) {
827 		printk(KERN_INFO "PCI: Using BIOS for IRQ routing\n");
828 		r->set = pirq_bios_set;
829 		r->name = "BIOS";
830 		return;
831 	}
832 #endif
833 
834 	/* Default unless a driver reloads it */
835 	r->name = "default";
836 	r->get = NULL;
837 	r->set = NULL;
838 
839 	DBG(KERN_DEBUG "PCI: Attempting to find IRQ router for [%04x:%04x]\n",
840 	    rt->rtr_vendor, rt->rtr_device);
841 
842 	pirq_router_dev = pci_get_domain_bus_and_slot(0, rt->rtr_bus,
843 						      rt->rtr_devfn);
844 	if (!pirq_router_dev) {
845 		DBG(KERN_DEBUG "PCI: Interrupt router not found at "
846 			"%02x:%02x\n", rt->rtr_bus, rt->rtr_devfn);
847 		return;
848 	}
849 
850 	for (h = pirq_routers; h->vendor; h++) {
851 		/* First look for a router match */
852 		if (rt->rtr_vendor == h->vendor &&
853 			h->probe(r, pirq_router_dev, rt->rtr_device))
854 			break;
855 		/* Fall back to a device match */
856 		if (pirq_router_dev->vendor == h->vendor &&
857 			h->probe(r, pirq_router_dev, pirq_router_dev->device))
858 			break;
859 	}
860 	dev_info(&pirq_router_dev->dev, "%s IRQ router [%04x:%04x]\n",
861 		 pirq_router.name,
862 		 pirq_router_dev->vendor, pirq_router_dev->device);
863 
864 	/* The device remains referenced for the kernel lifetime */
865 }
866 
867 static struct irq_info *pirq_get_info(struct pci_dev *dev)
868 {
869 	struct irq_routing_table *rt = pirq_table;
870 	int entries = (rt->size - sizeof(struct irq_routing_table)) /
871 		sizeof(struct irq_info);
872 	struct irq_info *info;
873 
874 	for (info = rt->slots; entries--; info++)
875 		if (info->bus == dev->bus->number &&
876 			PCI_SLOT(info->devfn) == PCI_SLOT(dev->devfn))
877 			return info;
878 	return NULL;
879 }
880 
881 static int pcibios_lookup_irq(struct pci_dev *dev, int assign)
882 {
883 	u8 pin;
884 	struct irq_info *info;
885 	int i, pirq, newirq;
886 	int irq = 0;
887 	u32 mask;
888 	struct irq_router *r = &pirq_router;
889 	struct pci_dev *dev2 = NULL;
890 	char *msg = NULL;
891 
892 	/* Find IRQ pin */
893 	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
894 	if (!pin) {
895 		dev_dbg(&dev->dev, "no interrupt pin\n");
896 		return 0;
897 	}
898 
899 	if (io_apic_assign_pci_irqs)
900 		return 0;
901 
902 	/* Find IRQ routing entry */
903 
904 	if (!pirq_table)
905 		return 0;
906 
907 	info = pirq_get_info(dev);
908 	if (!info) {
909 		dev_dbg(&dev->dev, "PCI INT %c not found in routing table\n",
910 			'A' + pin - 1);
911 		return 0;
912 	}
913 	pirq = info->irq[pin - 1].link;
914 	mask = info->irq[pin - 1].bitmap;
915 	if (!pirq) {
916 		dev_dbg(&dev->dev, "PCI INT %c not routed\n", 'A' + pin - 1);
917 		return 0;
918 	}
919 	dev_dbg(&dev->dev, "PCI INT %c -> PIRQ %02x, mask %04x, excl %04x",
920 		'A' + pin - 1, pirq, mask, pirq_table->exclusive_irqs);
921 	mask &= pcibios_irq_mask;
922 
923 	/* Work around broken HP Pavilion Notebooks which assign USB to
924 	   IRQ 9 even though it is actually wired to IRQ 11 */
925 
926 	if (broken_hp_bios_irq9 && pirq == 0x59 && dev->irq == 9) {
927 		dev->irq = 11;
928 		pci_write_config_byte(dev, PCI_INTERRUPT_LINE, 11);
929 		r->set(pirq_router_dev, dev, pirq, 11);
930 	}
931 
932 	/* same for Acer Travelmate 360, but with CB and irq 11 -> 10 */
933 	if (acer_tm360_irqrouting && dev->irq == 11 &&
934 		dev->vendor == PCI_VENDOR_ID_O2) {
935 		pirq = 0x68;
936 		mask = 0x400;
937 		dev->irq = r->get(pirq_router_dev, dev, pirq);
938 		pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq);
939 	}
940 
941 	/*
942 	 * Find the best IRQ to assign: use the one
943 	 * reported by the device if possible.
944 	 */
945 	newirq = dev->irq;
946 	if (newirq && !((1 << newirq) & mask)) {
947 		if (pci_probe & PCI_USE_PIRQ_MASK)
948 			newirq = 0;
949 		else
950 			dev_warn(&dev->dev, "IRQ %d doesn't match PIRQ mask "
951 				 "%#x; try pci=usepirqmask\n", newirq, mask);
952 	}
953 	if (!newirq && assign) {
954 		for (i = 0; i < 16; i++) {
955 			if (!(mask & (1 << i)))
956 				continue;
957 			if (pirq_penalty[i] < pirq_penalty[newirq] &&
958 				can_request_irq(i, IRQF_SHARED))
959 				newirq = i;
960 		}
961 	}
962 	dev_dbg(&dev->dev, "PCI INT %c -> newirq %d", 'A' + pin - 1, newirq);
963 
964 	/* Check if it is hardcoded */
965 	if ((pirq & 0xf0) == 0xf0) {
966 		irq = pirq & 0xf;
967 		msg = "hardcoded";
968 	} else if (r->get && (irq = r->get(pirq_router_dev, dev, pirq)) && \
969 	((!(pci_probe & PCI_USE_PIRQ_MASK)) || ((1 << irq) & mask))) {
970 		msg = "found";
971 		elcr_set_level_irq(irq);
972 	} else if (newirq && r->set &&
973 		(dev->class >> 8) != PCI_CLASS_DISPLAY_VGA) {
974 		if (r->set(pirq_router_dev, dev, pirq, newirq)) {
975 			elcr_set_level_irq(newirq);
976 			msg = "assigned";
977 			irq = newirq;
978 		}
979 	}
980 
981 	if (!irq) {
982 		if (newirq && mask == (1 << newirq)) {
983 			msg = "guessed";
984 			irq = newirq;
985 		} else {
986 			dev_dbg(&dev->dev, "can't route interrupt\n");
987 			return 0;
988 		}
989 	}
990 	dev_info(&dev->dev, "%s PCI INT %c -> IRQ %d\n", msg, 'A' + pin - 1, irq);
991 
992 	/* Update IRQ for all devices with the same pirq value */
993 	for_each_pci_dev(dev2) {
994 		pci_read_config_byte(dev2, PCI_INTERRUPT_PIN, &pin);
995 		if (!pin)
996 			continue;
997 
998 		info = pirq_get_info(dev2);
999 		if (!info)
1000 			continue;
1001 		if (info->irq[pin - 1].link == pirq) {
1002 			/*
1003 			 * We refuse to override the dev->irq
1004 			 * information. Give a warning!
1005 			 */
1006 			if (dev2->irq && dev2->irq != irq && \
1007 			(!(pci_probe & PCI_USE_PIRQ_MASK) || \
1008 			((1 << dev2->irq) & mask))) {
1009 #ifndef CONFIG_PCI_MSI
1010 				dev_info(&dev2->dev, "IRQ routing conflict: "
1011 					 "have IRQ %d, want IRQ %d\n",
1012 					 dev2->irq, irq);
1013 #endif
1014 				continue;
1015 			}
1016 			dev2->irq = irq;
1017 			pirq_penalty[irq]++;
1018 			if (dev != dev2)
1019 				dev_info(&dev->dev, "sharing IRQ %d with %s\n",
1020 					 irq, pci_name(dev2));
1021 		}
1022 	}
1023 	return 1;
1024 }
1025 
1026 void __init pcibios_fixup_irqs(void)
1027 {
1028 	struct pci_dev *dev = NULL;
1029 	u8 pin;
1030 
1031 	DBG(KERN_DEBUG "PCI: IRQ fixup\n");
1032 	for_each_pci_dev(dev) {
1033 		/*
1034 		 * If the BIOS has set an out of range IRQ number, just
1035 		 * ignore it.  Also keep track of which IRQ's are
1036 		 * already in use.
1037 		 */
1038 		if (dev->irq >= 16) {
1039 			dev_dbg(&dev->dev, "ignoring bogus IRQ %d\n", dev->irq);
1040 			dev->irq = 0;
1041 		}
1042 		/*
1043 		 * If the IRQ is already assigned to a PCI device,
1044 		 * ignore its ISA use penalty
1045 		 */
1046 		if (pirq_penalty[dev->irq] >= 100 &&
1047 				pirq_penalty[dev->irq] < 100000)
1048 			pirq_penalty[dev->irq] = 0;
1049 		pirq_penalty[dev->irq]++;
1050 	}
1051 
1052 	if (io_apic_assign_pci_irqs)
1053 		return;
1054 
1055 	dev = NULL;
1056 	for_each_pci_dev(dev) {
1057 		pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
1058 		if (!pin)
1059 			continue;
1060 
1061 		/*
1062 		 * Still no IRQ? Try to lookup one...
1063 		 */
1064 		if (!dev->irq)
1065 			pcibios_lookup_irq(dev, 0);
1066 	}
1067 }
1068 
1069 /*
1070  * Work around broken HP Pavilion Notebooks which assign USB to
1071  * IRQ 9 even though it is actually wired to IRQ 11
1072  */
1073 static int __init fix_broken_hp_bios_irq9(const struct dmi_system_id *d)
1074 {
1075 	if (!broken_hp_bios_irq9) {
1076 		broken_hp_bios_irq9 = 1;
1077 		printk(KERN_INFO "%s detected - fixing broken IRQ routing\n",
1078 			d->ident);
1079 	}
1080 	return 0;
1081 }
1082 
1083 /*
1084  * Work around broken Acer TravelMate 360 Notebooks which assign
1085  * Cardbus to IRQ 11 even though it is actually wired to IRQ 10
1086  */
1087 static int __init fix_acer_tm360_irqrouting(const struct dmi_system_id *d)
1088 {
1089 	if (!acer_tm360_irqrouting) {
1090 		acer_tm360_irqrouting = 1;
1091 		printk(KERN_INFO "%s detected - fixing broken IRQ routing\n",
1092 			d->ident);
1093 	}
1094 	return 0;
1095 }
1096 
1097 static const struct dmi_system_id pciirq_dmi_table[] __initconst = {
1098 	{
1099 		.callback = fix_broken_hp_bios_irq9,
1100 		.ident = "HP Pavilion N5400 Series Laptop",
1101 		.matches = {
1102 			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1103 			DMI_MATCH(DMI_BIOS_VERSION, "GE.M1.03"),
1104 			DMI_MATCH(DMI_PRODUCT_VERSION,
1105 				"HP Pavilion Notebook Model GE"),
1106 			DMI_MATCH(DMI_BOARD_VERSION, "OmniBook N32N-736"),
1107 		},
1108 	},
1109 	{
1110 		.callback = fix_acer_tm360_irqrouting,
1111 		.ident = "Acer TravelMate 36x Laptop",
1112 		.matches = {
1113 			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
1114 			DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 360"),
1115 		},
1116 	},
1117 	{ }
1118 };
1119 
1120 void __init pcibios_irq_init(void)
1121 {
1122 	struct irq_routing_table *rtable = NULL;
1123 
1124 	DBG(KERN_DEBUG "PCI: IRQ init\n");
1125 
1126 	if (raw_pci_ops == NULL)
1127 		return;
1128 
1129 	dmi_check_system(pciirq_dmi_table);
1130 
1131 	pirq_table = pirq_find_routing_table();
1132 
1133 #ifdef CONFIG_PCI_BIOS
1134 	if (!pirq_table && (pci_probe & PCI_BIOS_IRQ_SCAN)) {
1135 		pirq_table = pcibios_get_irq_routing_table();
1136 		rtable = pirq_table;
1137 	}
1138 #endif
1139 	if (pirq_table) {
1140 		pirq_peer_trick();
1141 		pirq_find_router(&pirq_router);
1142 		if (pirq_table->exclusive_irqs) {
1143 			int i;
1144 			for (i = 0; i < 16; i++)
1145 				if (!(pirq_table->exclusive_irqs & (1 << i)))
1146 					pirq_penalty[i] += 100;
1147 		}
1148 		/*
1149 		 * If we're using the I/O APIC, avoid using the PCI IRQ
1150 		 * routing table
1151 		 */
1152 		if (io_apic_assign_pci_irqs) {
1153 			kfree(rtable);
1154 			pirq_table = NULL;
1155 		}
1156 	}
1157 
1158 	x86_init.pci.fixup_irqs();
1159 
1160 	if (io_apic_assign_pci_irqs && pci_routeirq) {
1161 		struct pci_dev *dev = NULL;
1162 		/*
1163 		 * PCI IRQ routing is set up by pci_enable_device(), but we
1164 		 * also do it here in case there are still broken drivers that
1165 		 * don't use pci_enable_device().
1166 		 */
1167 		printk(KERN_INFO "PCI: Routing PCI interrupts for all devices because \"pci=routeirq\" specified\n");
1168 		for_each_pci_dev(dev)
1169 			pirq_enable_irq(dev);
1170 	}
1171 }
1172 
1173 static void pirq_penalize_isa_irq(int irq, int active)
1174 {
1175 	/*
1176 	 *  If any ISAPnP device reports an IRQ in its list of possible
1177 	 *  IRQ's, we try to avoid assigning it to PCI devices.
1178 	 */
1179 	if (irq < 16) {
1180 		if (active)
1181 			pirq_penalty[irq] += 1000;
1182 		else
1183 			pirq_penalty[irq] += 100;
1184 	}
1185 }
1186 
1187 void pcibios_penalize_isa_irq(int irq, int active)
1188 {
1189 #ifdef CONFIG_ACPI
1190 	if (!acpi_noirq)
1191 		acpi_penalize_isa_irq(irq, active);
1192 	else
1193 #endif
1194 		pirq_penalize_isa_irq(irq, active);
1195 }
1196 
1197 static int pirq_enable_irq(struct pci_dev *dev)
1198 {
1199 	u8 pin = 0;
1200 
1201 	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
1202 	if (pin && !pcibios_lookup_irq(dev, 1)) {
1203 		char *msg = "";
1204 
1205 		if (!io_apic_assign_pci_irqs && dev->irq)
1206 			return 0;
1207 
1208 		if (io_apic_assign_pci_irqs) {
1209 #ifdef CONFIG_X86_IO_APIC
1210 			struct pci_dev *temp_dev;
1211 			int irq;
1212 
1213 			if (dev->irq_managed && dev->irq > 0)
1214 				return 0;
1215 
1216 			irq = IO_APIC_get_PCI_irq_vector(dev->bus->number,
1217 						PCI_SLOT(dev->devfn), pin - 1);
1218 			/*
1219 			 * Busses behind bridges are typically not listed in the MP-table.
1220 			 * In this case we have to look up the IRQ based on the parent bus,
1221 			 * parent slot, and pin number. The SMP code detects such bridged
1222 			 * busses itself so we should get into this branch reliably.
1223 			 */
1224 			temp_dev = dev;
1225 			while (irq < 0 && dev->bus->parent) { /* go back to the bridge */
1226 				struct pci_dev *bridge = dev->bus->self;
1227 
1228 				pin = pci_swizzle_interrupt_pin(dev, pin);
1229 				irq = IO_APIC_get_PCI_irq_vector(bridge->bus->number,
1230 						PCI_SLOT(bridge->devfn),
1231 						pin - 1);
1232 				if (irq >= 0)
1233 					dev_warn(&dev->dev, "using bridge %s "
1234 						 "INT %c to get IRQ %d\n",
1235 						 pci_name(bridge), 'A' + pin - 1,
1236 						 irq);
1237 				dev = bridge;
1238 			}
1239 			dev = temp_dev;
1240 			if (irq >= 0) {
1241 				dev->irq_managed = 1;
1242 				dev->irq = irq;
1243 				dev_info(&dev->dev, "PCI->APIC IRQ transform: "
1244 					 "INT %c -> IRQ %d\n", 'A' + pin - 1, irq);
1245 				return 0;
1246 			} else
1247 				msg = "; probably buggy MP table";
1248 #endif
1249 		} else if (pci_probe & PCI_BIOS_IRQ_SCAN)
1250 			msg = "";
1251 		else
1252 			msg = "; please try using pci=biosirq";
1253 
1254 		/*
1255 		 * With IDE legacy devices the IRQ lookup failure is not
1256 		 * a problem..
1257 		 */
1258 		if (dev->class >> 8 == PCI_CLASS_STORAGE_IDE &&
1259 				!(dev->class & 0x5))
1260 			return 0;
1261 
1262 		dev_warn(&dev->dev, "can't find IRQ for PCI INT %c%s\n",
1263 			 'A' + pin - 1, msg);
1264 	}
1265 	return 0;
1266 }
1267 
1268 bool mp_should_keep_irq(struct device *dev)
1269 {
1270 	if (dev->power.is_prepared)
1271 		return true;
1272 #ifdef CONFIG_PM
1273 	if (dev->power.runtime_status == RPM_SUSPENDING)
1274 		return true;
1275 #endif
1276 
1277 	return false;
1278 }
1279 
1280 static void pirq_disable_irq(struct pci_dev *dev)
1281 {
1282 	if (io_apic_assign_pci_irqs && !mp_should_keep_irq(&dev->dev) &&
1283 	    dev->irq_managed && dev->irq) {
1284 		mp_unmap_irq(dev->irq);
1285 		dev->irq = 0;
1286 		dev->irq_managed = 0;
1287 	}
1288 }
1289