xref: /linux/arch/x86/pci/irq.c (revision 8fa5723aa7e053d498336b48448b292fc2e0458b)
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/slab.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 
20 #include "pci.h"
21 
22 #define PIRQ_SIGNATURE	(('$' << 0) + ('P' << 8) + ('I' << 16) + ('R' << 24))
23 #define PIRQ_VERSION 0x0100
24 
25 static int broken_hp_bios_irq9;
26 static int acer_tm360_irqrouting;
27 
28 static struct irq_routing_table *pirq_table;
29 
30 static int pirq_enable_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) = NULL;
58 void (*pcibios_disable_irq)(struct pci_dev *dev) = NULL;
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 		int node;
142 		if (!busmap[i] || pci_find_bus(0, i))
143 			continue;
144 		node = get_mp_bus_to_node(i);
145 		if (pci_scan_bus_on_node(i, &pci_root_ops, node))
146 			printk(KERN_INFO "PCI: Discovered primary peer "
147 			       "bus %02x [IRQ]\n", i);
148 	}
149 	pcibios_last_bus = -1;
150 }
151 
152 /*
153  *  Code for querying and setting of IRQ routes on various interrupt routers.
154  */
155 
156 void eisa_set_level_irq(unsigned int irq)
157 {
158 	unsigned char mask = 1 << (irq & 7);
159 	unsigned int port = 0x4d0 + (irq >> 3);
160 	unsigned char val;
161 	static u16 eisa_irq_mask;
162 
163 	if (irq >= 16 || (1 << irq) & eisa_irq_mask)
164 		return;
165 
166 	eisa_irq_mask |= (1 << irq);
167 	printk(KERN_DEBUG "PCI: setting IRQ %u as level-triggered\n", irq);
168 	val = inb(port);
169 	if (!(val & mask)) {
170 		DBG(KERN_DEBUG " -> edge");
171 		outb(val | mask, port);
172 	}
173 }
174 
175 /*
176  * Common IRQ routing practice: nibbles in config space,
177  * offset by some magic constant.
178  */
179 static unsigned int read_config_nybble(struct pci_dev *router, unsigned offset, unsigned nr)
180 {
181 	u8 x;
182 	unsigned reg = offset + (nr >> 1);
183 
184 	pci_read_config_byte(router, reg, &x);
185 	return (nr & 1) ? (x >> 4) : (x & 0xf);
186 }
187 
188 static void write_config_nybble(struct pci_dev *router, unsigned offset,
189 	unsigned nr, unsigned int val)
190 {
191 	u8 x;
192 	unsigned reg = offset + (nr >> 1);
193 
194 	pci_read_config_byte(router, reg, &x);
195 	x = (nr & 1) ? ((x & 0x0f) | (val << 4)) : ((x & 0xf0) | val);
196 	pci_write_config_byte(router, reg, x);
197 }
198 
199 /*
200  * ALI pirq entries are damn ugly, and completely undocumented.
201  * This has been figured out from pirq tables, and it's not a pretty
202  * picture.
203  */
204 static int pirq_ali_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
205 {
206 	static const unsigned char irqmap[16] = { 0, 9, 3, 10, 4, 5, 7, 6, 1, 11, 0, 12, 0, 14, 0, 15 };
207 
208 	WARN_ON_ONCE(pirq > 16);
209 	return irqmap[read_config_nybble(router, 0x48, pirq-1)];
210 }
211 
212 static int pirq_ali_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
213 {
214 	static const unsigned char irqmap[16] = { 0, 8, 0, 2, 4, 5, 7, 6, 0, 1, 3, 9, 11, 0, 13, 15 };
215 	unsigned int val = irqmap[irq];
216 
217 	WARN_ON_ONCE(pirq > 16);
218 	if (val) {
219 		write_config_nybble(router, 0x48, pirq-1, val);
220 		return 1;
221 	}
222 	return 0;
223 }
224 
225 /*
226  * The Intel PIIX4 pirq rules are fairly simple: "pirq" is
227  * just a pointer to the config space.
228  */
229 static int pirq_piix_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
230 {
231 	u8 x;
232 
233 	pci_read_config_byte(router, pirq, &x);
234 	return (x < 16) ? x : 0;
235 }
236 
237 static int pirq_piix_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
238 {
239 	pci_write_config_byte(router, pirq, irq);
240 	return 1;
241 }
242 
243 /*
244  * The VIA pirq rules are nibble-based, like ALI,
245  * but without the ugly irq number munging.
246  * However, PIRQD is in the upper instead of lower 4 bits.
247  */
248 static int pirq_via_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
249 {
250 	return read_config_nybble(router, 0x55, pirq == 4 ? 5 : pirq);
251 }
252 
253 static int pirq_via_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
254 {
255 	write_config_nybble(router, 0x55, pirq == 4 ? 5 : pirq, irq);
256 	return 1;
257 }
258 
259 /*
260  * The VIA pirq rules are nibble-based, like ALI,
261  * but without the ugly irq number munging.
262  * However, for 82C586, nibble map is different .
263  */
264 static int pirq_via586_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
265 {
266 	static const unsigned int pirqmap[5] = { 3, 2, 5, 1, 1 };
267 
268 	WARN_ON_ONCE(pirq > 5);
269 	return read_config_nybble(router, 0x55, pirqmap[pirq-1]);
270 }
271 
272 static int pirq_via586_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
273 {
274 	static const unsigned int pirqmap[5] = { 3, 2, 5, 1, 1 };
275 
276 	WARN_ON_ONCE(pirq > 5);
277 	write_config_nybble(router, 0x55, pirqmap[pirq-1], irq);
278 	return 1;
279 }
280 
281 /*
282  * ITE 8330G pirq rules are nibble-based
283  * FIXME: pirqmap may be { 1, 0, 3, 2 },
284  * 	  2+3 are both mapped to irq 9 on my system
285  */
286 static int pirq_ite_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
287 {
288 	static const unsigned char pirqmap[4] = { 1, 0, 2, 3 };
289 
290 	WARN_ON_ONCE(pirq > 4);
291 	return read_config_nybble(router, 0x43, pirqmap[pirq-1]);
292 }
293 
294 static int pirq_ite_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
295 {
296 	static const unsigned char pirqmap[4] = { 1, 0, 2, 3 };
297 
298 	WARN_ON_ONCE(pirq > 4);
299 	write_config_nybble(router, 0x43, pirqmap[pirq-1], irq);
300 	return 1;
301 }
302 
303 /*
304  * OPTI: high four bits are nibble pointer..
305  * I wonder what the low bits do?
306  */
307 static int pirq_opti_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
308 {
309 	return read_config_nybble(router, 0xb8, pirq >> 4);
310 }
311 
312 static int pirq_opti_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
313 {
314 	write_config_nybble(router, 0xb8, pirq >> 4, irq);
315 	return 1;
316 }
317 
318 /*
319  * Cyrix: nibble offset 0x5C
320  * 0x5C bits 7:4 is INTB bits 3:0 is INTA
321  * 0x5D bits 7:4 is INTD bits 3:0 is INTC
322  */
323 static int pirq_cyrix_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
324 {
325 	return read_config_nybble(router, 0x5C, (pirq-1)^1);
326 }
327 
328 static int pirq_cyrix_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
329 {
330 	write_config_nybble(router, 0x5C, (pirq-1)^1, irq);
331 	return 1;
332 }
333 
334 /*
335  *	PIRQ routing for SiS 85C503 router used in several SiS chipsets.
336  *	We have to deal with the following issues here:
337  *	- vendors have different ideas about the meaning of link values
338  *	- some onboard devices (integrated in the chipset) have special
339  *	  links and are thus routed differently (i.e. not via PCI INTA-INTD)
340  *	- different revision of the router have a different layout for
341  *	  the routing registers, particularly for the onchip devices
342  *
343  *	For all routing registers the common thing is we have one byte
344  *	per routeable link which is defined as:
345  *		 bit 7      IRQ mapping enabled (0) or disabled (1)
346  *		 bits [6:4] reserved (sometimes used for onchip devices)
347  *		 bits [3:0] IRQ to map to
348  *		     allowed: 3-7, 9-12, 14-15
349  *		     reserved: 0, 1, 2, 8, 13
350  *
351  *	The config-space registers located at 0x41/0x42/0x43/0x44 are
352  *	always used to route the normal PCI INT A/B/C/D respectively.
353  *	Apparently there are systems implementing PCI routing table using
354  *	link values 0x01-0x04 and others using 0x41-0x44 for PCI INTA..D.
355  *	We try our best to handle both link mappings.
356  *
357  *	Currently (2003-05-21) it appears most SiS chipsets follow the
358  *	definition of routing registers from the SiS-5595 southbridge.
359  *	According to the SiS 5595 datasheets the revision id's of the
360  *	router (ISA-bridge) should be 0x01 or 0xb0.
361  *
362  *	Furthermore we've also seen lspci dumps with revision 0x00 and 0xb1.
363  *	Looks like these are used in a number of SiS 5xx/6xx/7xx chipsets.
364  *	They seem to work with the current routing code. However there is
365  *	some concern because of the two USB-OHCI HCs (original SiS 5595
366  *	had only one). YMMV.
367  *
368  *	Onchip routing for router rev-id 0x01/0xb0 and probably 0x00/0xb1:
369  *
370  *	0x61:	IDEIRQ:
371  *		bits [6:5] must be written 01
372  *		bit 4 channel-select primary (0), secondary (1)
373  *
374  *	0x62:	USBIRQ:
375  *		bit 6 OHCI function disabled (0), enabled (1)
376  *
377  *	0x6a:	ACPI/SCI IRQ: bits 4-6 reserved
378  *
379  *	0x7e:	Data Acq. Module IRQ - bits 4-6 reserved
380  *
381  *	We support USBIRQ (in addition to INTA-INTD) and keep the
382  *	IDE, ACPI and DAQ routing untouched as set by the BIOS.
383  *
384  *	Currently the only reported exception is the new SiS 65x chipset
385  *	which includes the SiS 69x southbridge. Here we have the 85C503
386  *	router revision 0x04 and there are changes in the register layout
387  *	mostly related to the different USB HCs with USB 2.0 support.
388  *
389  *	Onchip routing for router rev-id 0x04 (try-and-error observation)
390  *
391  *	0x60/0x61/0x62/0x63:	1xEHCI and 3xOHCI (companion) USB-HCs
392  *				bit 6-4 are probably unused, not like 5595
393  */
394 
395 #define PIRQ_SIS_IRQ_MASK	0x0f
396 #define PIRQ_SIS_IRQ_DISABLE	0x80
397 #define PIRQ_SIS_USB_ENABLE	0x40
398 
399 static int pirq_sis_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
400 {
401 	u8 x;
402 	int reg;
403 
404 	reg = pirq;
405 	if (reg >= 0x01 && reg <= 0x04)
406 		reg += 0x40;
407 	pci_read_config_byte(router, reg, &x);
408 	return (x & PIRQ_SIS_IRQ_DISABLE) ? 0 : (x & PIRQ_SIS_IRQ_MASK);
409 }
410 
411 static int pirq_sis_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
412 {
413 	u8 x;
414 	int reg;
415 
416 	reg = pirq;
417 	if (reg >= 0x01 && reg <= 0x04)
418 		reg += 0x40;
419 	pci_read_config_byte(router, reg, &x);
420 	x &= ~(PIRQ_SIS_IRQ_MASK | PIRQ_SIS_IRQ_DISABLE);
421 	x |= irq ? irq: PIRQ_SIS_IRQ_DISABLE;
422 	pci_write_config_byte(router, reg, x);
423 	return 1;
424 }
425 
426 
427 /*
428  * VLSI: nibble offset 0x74 - educated guess due to routing table and
429  *       config space of VLSI 82C534 PCI-bridge/router (1004:0102)
430  *       Tested on HP OmniBook 800 covering PIRQ 1, 2, 4, 8 for onboard
431  *       devices, PIRQ 3 for non-pci(!) soundchip and (untested) PIRQ 6
432  *       for the busbridge to the docking station.
433  */
434 
435 static int pirq_vlsi_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
436 {
437 	WARN_ON_ONCE(pirq >= 9);
438 	if (pirq > 8) {
439 		dev_info(&dev->dev, "VLSI router PIRQ escape (%d)\n", pirq);
440 		return 0;
441 	}
442 	return read_config_nybble(router, 0x74, pirq-1);
443 }
444 
445 static int pirq_vlsi_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
446 {
447 	WARN_ON_ONCE(pirq >= 9);
448 	if (pirq > 8) {
449 		dev_info(&dev->dev, "VLSI router PIRQ escape (%d)\n", pirq);
450 		return 0;
451 	}
452 	write_config_nybble(router, 0x74, pirq-1, irq);
453 	return 1;
454 }
455 
456 /*
457  * ServerWorks: PCI interrupts mapped to system IRQ lines through Index
458  * and Redirect I/O registers (0x0c00 and 0x0c01).  The Index register
459  * format is (PCIIRQ## | 0x10), e.g.: PCIIRQ10=0x1a.  The Redirect
460  * register is a straight binary coding of desired PIC IRQ (low nibble).
461  *
462  * The 'link' value in the PIRQ table is already in the correct format
463  * for the Index register.  There are some special index values:
464  * 0x00 for ACPI (SCI), 0x01 for USB, 0x02 for IDE0, 0x04 for IDE1,
465  * and 0x03 for SMBus.
466  */
467 static int pirq_serverworks_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
468 {
469 	outb(pirq, 0xc00);
470 	return inb(0xc01) & 0xf;
471 }
472 
473 static int pirq_serverworks_set(struct pci_dev *router, struct pci_dev *dev,
474 	int pirq, int irq)
475 {
476 	outb(pirq, 0xc00);
477 	outb(irq, 0xc01);
478 	return 1;
479 }
480 
481 /* Support for AMD756 PCI IRQ Routing
482  * Jhon H. Caicedo <jhcaiced@osso.org.co>
483  * Jun/21/2001 0.2.0 Release, fixed to use "nybble" functions... (jhcaiced)
484  * Jun/19/2001 Alpha Release 0.1.0 (jhcaiced)
485  * The AMD756 pirq rules are nibble-based
486  * offset 0x56 0-3 PIRQA  4-7  PIRQB
487  * offset 0x57 0-3 PIRQC  4-7  PIRQD
488  */
489 static int pirq_amd756_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
490 {
491 	u8 irq;
492 	irq = 0;
493 	if (pirq <= 4)
494 		irq = read_config_nybble(router, 0x56, pirq - 1);
495 	dev_info(&dev->dev,
496 		 "AMD756: dev [%04x:%04x], router PIRQ %d get IRQ %d\n",
497 		 dev->vendor, dev->device, pirq, irq);
498 	return irq;
499 }
500 
501 static int pirq_amd756_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
502 {
503 	dev_info(&dev->dev,
504 		 "AMD756: dev [%04x:%04x], router PIRQ %d set IRQ %d\n",
505 		 dev->vendor, dev->device, pirq, irq);
506 	if (pirq <= 4)
507 		write_config_nybble(router, 0x56, pirq - 1, irq);
508 	return 1;
509 }
510 
511 /*
512  * PicoPower PT86C523
513  */
514 static int pirq_pico_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
515 {
516 	outb(0x10 + ((pirq - 1) >> 1), 0x24);
517 	return ((pirq - 1) & 1) ? (inb(0x26) >> 4) : (inb(0x26) & 0xf);
518 }
519 
520 static int pirq_pico_set(struct pci_dev *router, struct pci_dev *dev, int pirq,
521 			int irq)
522 {
523 	unsigned int x;
524 	outb(0x10 + ((pirq - 1) >> 1), 0x24);
525 	x = inb(0x26);
526 	x = ((pirq - 1) & 1) ? ((x & 0x0f) | (irq << 4)) : ((x & 0xf0) | (irq));
527 	outb(x, 0x26);
528 	return 1;
529 }
530 
531 #ifdef CONFIG_PCI_BIOS
532 
533 static int pirq_bios_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
534 {
535 	struct pci_dev *bridge;
536 	int pin = pci_get_interrupt_pin(dev, &bridge);
537 	return pcibios_set_irq_routing(bridge, pin, irq);
538 }
539 
540 #endif
541 
542 static __init int intel_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
543 {
544 	static struct pci_device_id __initdata pirq_440gx[] = {
545 		{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443GX_0) },
546 		{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443GX_2) },
547 		{ },
548 	};
549 
550 	/* 440GX has a proprietary PIRQ router -- don't use it */
551 	if (pci_dev_present(pirq_440gx))
552 		return 0;
553 
554 	switch (device) {
555 	case PCI_DEVICE_ID_INTEL_82371FB_0:
556 	case PCI_DEVICE_ID_INTEL_82371SB_0:
557 	case PCI_DEVICE_ID_INTEL_82371AB_0:
558 	case PCI_DEVICE_ID_INTEL_82371MX:
559 	case PCI_DEVICE_ID_INTEL_82443MX_0:
560 	case PCI_DEVICE_ID_INTEL_82801AA_0:
561 	case PCI_DEVICE_ID_INTEL_82801AB_0:
562 	case PCI_DEVICE_ID_INTEL_82801BA_0:
563 	case PCI_DEVICE_ID_INTEL_82801BA_10:
564 	case PCI_DEVICE_ID_INTEL_82801CA_0:
565 	case PCI_DEVICE_ID_INTEL_82801CA_12:
566 	case PCI_DEVICE_ID_INTEL_82801DB_0:
567 	case PCI_DEVICE_ID_INTEL_82801E_0:
568 	case PCI_DEVICE_ID_INTEL_82801EB_0:
569 	case PCI_DEVICE_ID_INTEL_ESB_1:
570 	case PCI_DEVICE_ID_INTEL_ICH6_0:
571 	case PCI_DEVICE_ID_INTEL_ICH6_1:
572 	case PCI_DEVICE_ID_INTEL_ICH7_0:
573 	case PCI_DEVICE_ID_INTEL_ICH7_1:
574 	case PCI_DEVICE_ID_INTEL_ICH7_30:
575 	case PCI_DEVICE_ID_INTEL_ICH7_31:
576 	case PCI_DEVICE_ID_INTEL_ESB2_0:
577 	case PCI_DEVICE_ID_INTEL_ICH8_0:
578 	case PCI_DEVICE_ID_INTEL_ICH8_1:
579 	case PCI_DEVICE_ID_INTEL_ICH8_2:
580 	case PCI_DEVICE_ID_INTEL_ICH8_3:
581 	case PCI_DEVICE_ID_INTEL_ICH8_4:
582 	case PCI_DEVICE_ID_INTEL_ICH9_0:
583 	case PCI_DEVICE_ID_INTEL_ICH9_1:
584 	case PCI_DEVICE_ID_INTEL_ICH9_2:
585 	case PCI_DEVICE_ID_INTEL_ICH9_3:
586 	case PCI_DEVICE_ID_INTEL_ICH9_4:
587 	case PCI_DEVICE_ID_INTEL_ICH9_5:
588 	case PCI_DEVICE_ID_INTEL_TOLAPAI_0:
589 	case PCI_DEVICE_ID_INTEL_ICH10_0:
590 	case PCI_DEVICE_ID_INTEL_ICH10_1:
591 	case PCI_DEVICE_ID_INTEL_ICH10_2:
592 	case PCI_DEVICE_ID_INTEL_ICH10_3:
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_PCH_LPC_MIN) &&
600 		(device <= PCI_DEVICE_ID_INTEL_PCH_LPC_MAX)) {
601 		r->name = "PIIX/ICH";
602 		r->get = pirq_piix_get;
603 		r->set = pirq_piix_set;
604 		return 1;
605 	}
606 
607 	return 0;
608 }
609 
610 static __init int via_router_probe(struct irq_router *r,
611 				struct pci_dev *router, u16 device)
612 {
613 	/* FIXME: We should move some of the quirk fixup stuff here */
614 
615 	/*
616 	 * workarounds for some buggy BIOSes
617 	 */
618 	if (device == PCI_DEVICE_ID_VIA_82C586_0) {
619 		switch (router->device) {
620 		case PCI_DEVICE_ID_VIA_82C686:
621 			/*
622 			 * Asus k7m bios wrongly reports 82C686A
623 			 * as 586-compatible
624 			 */
625 			device = PCI_DEVICE_ID_VIA_82C686;
626 			break;
627 		case PCI_DEVICE_ID_VIA_8235:
628 			/**
629 			 * Asus a7v-x bios wrongly reports 8235
630 			 * as 586-compatible
631 			 */
632 			device = PCI_DEVICE_ID_VIA_8235;
633 			break;
634 		case PCI_DEVICE_ID_VIA_8237:
635 			/**
636 			 * Asus a7v600 bios wrongly reports 8237
637 			 * as 586-compatible
638 			 */
639 			device = PCI_DEVICE_ID_VIA_8237;
640 			break;
641 		}
642 	}
643 
644 	switch (device) {
645 	case PCI_DEVICE_ID_VIA_82C586_0:
646 		r->name = "VIA";
647 		r->get = pirq_via586_get;
648 		r->set = pirq_via586_set;
649 		return 1;
650 	case PCI_DEVICE_ID_VIA_82C596:
651 	case PCI_DEVICE_ID_VIA_82C686:
652 	case PCI_DEVICE_ID_VIA_8231:
653 	case PCI_DEVICE_ID_VIA_8233A:
654 	case PCI_DEVICE_ID_VIA_8235:
655 	case PCI_DEVICE_ID_VIA_8237:
656 		/* FIXME: add new ones for 8233/5 */
657 		r->name = "VIA";
658 		r->get = pirq_via_get;
659 		r->set = pirq_via_set;
660 		return 1;
661 	}
662 	return 0;
663 }
664 
665 static __init int vlsi_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
666 {
667 	switch (device) {
668 	case PCI_DEVICE_ID_VLSI_82C534:
669 		r->name = "VLSI 82C534";
670 		r->get = pirq_vlsi_get;
671 		r->set = pirq_vlsi_set;
672 		return 1;
673 	}
674 	return 0;
675 }
676 
677 
678 static __init int serverworks_router_probe(struct irq_router *r,
679 		struct pci_dev *router, u16 device)
680 {
681 	switch (device) {
682 	case PCI_DEVICE_ID_SERVERWORKS_OSB4:
683 	case PCI_DEVICE_ID_SERVERWORKS_CSB5:
684 		r->name = "ServerWorks";
685 		r->get = pirq_serverworks_get;
686 		r->set = pirq_serverworks_set;
687 		return 1;
688 	}
689 	return 0;
690 }
691 
692 static __init int sis_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
693 {
694 	if (device != PCI_DEVICE_ID_SI_503)
695 		return 0;
696 
697 	r->name = "SIS";
698 	r->get = pirq_sis_get;
699 	r->set = pirq_sis_set;
700 	return 1;
701 }
702 
703 static __init int cyrix_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
704 {
705 	switch (device) {
706 	case PCI_DEVICE_ID_CYRIX_5520:
707 		r->name = "NatSemi";
708 		r->get = pirq_cyrix_get;
709 		r->set = pirq_cyrix_set;
710 		return 1;
711 	}
712 	return 0;
713 }
714 
715 static __init int opti_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
716 {
717 	switch (device) {
718 	case PCI_DEVICE_ID_OPTI_82C700:
719 		r->name = "OPTI";
720 		r->get = pirq_opti_get;
721 		r->set = pirq_opti_set;
722 		return 1;
723 	}
724 	return 0;
725 }
726 
727 static __init int ite_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
728 {
729 	switch (device) {
730 	case PCI_DEVICE_ID_ITE_IT8330G_0:
731 		r->name = "ITE";
732 		r->get = pirq_ite_get;
733 		r->set = pirq_ite_set;
734 		return 1;
735 	}
736 	return 0;
737 }
738 
739 static __init int ali_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
740 {
741 	switch (device) {
742 	case PCI_DEVICE_ID_AL_M1533:
743 	case PCI_DEVICE_ID_AL_M1563:
744 		r->name = "ALI";
745 		r->get = pirq_ali_get;
746 		r->set = pirq_ali_set;
747 		return 1;
748 	}
749 	return 0;
750 }
751 
752 static __init int amd_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
753 {
754 	switch (device) {
755 	case PCI_DEVICE_ID_AMD_VIPER_740B:
756 		r->name = "AMD756";
757 		break;
758 	case PCI_DEVICE_ID_AMD_VIPER_7413:
759 		r->name = "AMD766";
760 		break;
761 	case PCI_DEVICE_ID_AMD_VIPER_7443:
762 		r->name = "AMD768";
763 		break;
764 	default:
765 		return 0;
766 	}
767 	r->get = pirq_amd756_get;
768 	r->set = pirq_amd756_set;
769 	return 1;
770 }
771 
772 static __init int pico_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
773 {
774 	switch (device) {
775 	case PCI_DEVICE_ID_PICOPOWER_PT86C523:
776 		r->name = "PicoPower PT86C523";
777 		r->get = pirq_pico_get;
778 		r->set = pirq_pico_set;
779 		return 1;
780 
781 	case PCI_DEVICE_ID_PICOPOWER_PT86C523BBP:
782 		r->name = "PicoPower PT86C523 rev. BB+";
783 		r->get = pirq_pico_get;
784 		r->set = pirq_pico_set;
785 		return 1;
786 	}
787 	return 0;
788 }
789 
790 static __initdata struct irq_router_handler pirq_routers[] = {
791 	{ PCI_VENDOR_ID_INTEL, intel_router_probe },
792 	{ PCI_VENDOR_ID_AL, ali_router_probe },
793 	{ PCI_VENDOR_ID_ITE, ite_router_probe },
794 	{ PCI_VENDOR_ID_VIA, via_router_probe },
795 	{ PCI_VENDOR_ID_OPTI, opti_router_probe },
796 	{ PCI_VENDOR_ID_SI, sis_router_probe },
797 	{ PCI_VENDOR_ID_CYRIX, cyrix_router_probe },
798 	{ PCI_VENDOR_ID_VLSI, vlsi_router_probe },
799 	{ PCI_VENDOR_ID_SERVERWORKS, serverworks_router_probe },
800 	{ PCI_VENDOR_ID_AMD, amd_router_probe },
801 	{ PCI_VENDOR_ID_PICOPOWER, pico_router_probe },
802 	/* Someone with docs needs to add the ATI Radeon IGP */
803 	{ 0, NULL }
804 };
805 static struct irq_router pirq_router;
806 static struct pci_dev *pirq_router_dev;
807 
808 
809 /*
810  *	FIXME: should we have an option to say "generic for
811  *	chipset" ?
812  */
813 
814 static void __init pirq_find_router(struct irq_router *r)
815 {
816 	struct irq_routing_table *rt = pirq_table;
817 	struct irq_router_handler *h;
818 
819 #ifdef CONFIG_PCI_BIOS
820 	if (!rt->signature) {
821 		printk(KERN_INFO "PCI: Using BIOS for IRQ routing\n");
822 		r->set = pirq_bios_set;
823 		r->name = "BIOS";
824 		return;
825 	}
826 #endif
827 
828 	/* Default unless a driver reloads it */
829 	r->name = "default";
830 	r->get = NULL;
831 	r->set = NULL;
832 
833 	DBG(KERN_DEBUG "PCI: Attempting to find IRQ router for [%04x:%04x]\n",
834 	    rt->rtr_vendor, rt->rtr_device);
835 
836 	pirq_router_dev = pci_get_bus_and_slot(rt->rtr_bus, rt->rtr_devfn);
837 	if (!pirq_router_dev) {
838 		DBG(KERN_DEBUG "PCI: Interrupt router not found at "
839 			"%02x:%02x\n", rt->rtr_bus, rt->rtr_devfn);
840 		return;
841 	}
842 
843 	for (h = pirq_routers; h->vendor; h++) {
844 		/* First look for a router match */
845 		if (rt->rtr_vendor == h->vendor &&
846 			h->probe(r, pirq_router_dev, rt->rtr_device))
847 			break;
848 		/* Fall back to a device match */
849 		if (pirq_router_dev->vendor == h->vendor &&
850 			h->probe(r, pirq_router_dev, pirq_router_dev->device))
851 			break;
852 	}
853 	dev_info(&pirq_router_dev->dev, "%s IRQ router [%04x:%04x]\n",
854 		 pirq_router.name,
855 		 pirq_router_dev->vendor, pirq_router_dev->device);
856 
857 	/* The device remains referenced for the kernel lifetime */
858 }
859 
860 static struct irq_info *pirq_get_info(struct pci_dev *dev)
861 {
862 	struct irq_routing_table *rt = pirq_table;
863 	int entries = (rt->size - sizeof(struct irq_routing_table)) /
864 		sizeof(struct irq_info);
865 	struct irq_info *info;
866 
867 	for (info = rt->slots; entries--; info++)
868 		if (info->bus == dev->bus->number &&
869 			PCI_SLOT(info->devfn) == PCI_SLOT(dev->devfn))
870 			return info;
871 	return NULL;
872 }
873 
874 static int pcibios_lookup_irq(struct pci_dev *dev, int assign)
875 {
876 	u8 pin;
877 	struct irq_info *info;
878 	int i, pirq, newirq;
879 	int irq = 0;
880 	u32 mask;
881 	struct irq_router *r = &pirq_router;
882 	struct pci_dev *dev2 = NULL;
883 	char *msg = NULL;
884 
885 	/* Find IRQ pin */
886 	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
887 	if (!pin) {
888 		dev_dbg(&dev->dev, "no interrupt pin\n");
889 		return 0;
890 	}
891 	pin = pin - 1;
892 
893 	/* Find IRQ routing entry */
894 
895 	if (!pirq_table)
896 		return 0;
897 
898 	info = pirq_get_info(dev);
899 	if (!info) {
900 		dev_dbg(&dev->dev, "PCI INT %c not found in routing table\n",
901 			'A' + pin);
902 		return 0;
903 	}
904 	pirq = info->irq[pin].link;
905 	mask = info->irq[pin].bitmap;
906 	if (!pirq) {
907 		dev_dbg(&dev->dev, "PCI INT %c not routed\n", 'A' + pin);
908 		return 0;
909 	}
910 	dev_dbg(&dev->dev, "PCI INT %c -> PIRQ %02x, mask %04x, excl %04x",
911 		'A' + pin, pirq, mask, pirq_table->exclusive_irqs);
912 	mask &= pcibios_irq_mask;
913 
914 	/* Work around broken HP Pavilion Notebooks which assign USB to
915 	   IRQ 9 even though it is actually wired to IRQ 11 */
916 
917 	if (broken_hp_bios_irq9 && pirq == 0x59 && dev->irq == 9) {
918 		dev->irq = 11;
919 		pci_write_config_byte(dev, PCI_INTERRUPT_LINE, 11);
920 		r->set(pirq_router_dev, dev, pirq, 11);
921 	}
922 
923 	/* same for Acer Travelmate 360, but with CB and irq 11 -> 10 */
924 	if (acer_tm360_irqrouting && dev->irq == 11 &&
925 		dev->vendor == PCI_VENDOR_ID_O2) {
926 		pirq = 0x68;
927 		mask = 0x400;
928 		dev->irq = r->get(pirq_router_dev, dev, pirq);
929 		pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq);
930 	}
931 
932 	/*
933 	 * Find the best IRQ to assign: use the one
934 	 * reported by the device if possible.
935 	 */
936 	newirq = dev->irq;
937 	if (newirq && !((1 << newirq) & mask)) {
938 		if (pci_probe & PCI_USE_PIRQ_MASK)
939 			newirq = 0;
940 		else
941 			dev_warn(&dev->dev, "IRQ %d doesn't match PIRQ mask "
942 				 "%#x; try pci=usepirqmask\n", newirq, mask);
943 	}
944 	if (!newirq && assign) {
945 		for (i = 0; i < 16; i++) {
946 			if (!(mask & (1 << i)))
947 				continue;
948 			if (pirq_penalty[i] < pirq_penalty[newirq] &&
949 				can_request_irq(i, IRQF_SHARED))
950 				newirq = i;
951 		}
952 	}
953 	dev_dbg(&dev->dev, "PCI INT %c -> newirq %d", 'A' + pin, newirq);
954 
955 	/* Check if it is hardcoded */
956 	if ((pirq & 0xf0) == 0xf0) {
957 		irq = pirq & 0xf;
958 		msg = "hardcoded";
959 	} else if (r->get && (irq = r->get(pirq_router_dev, dev, pirq)) && \
960 	((!(pci_probe & PCI_USE_PIRQ_MASK)) || ((1 << irq) & mask))) {
961 		msg = "found";
962 		eisa_set_level_irq(irq);
963 	} else if (newirq && r->set &&
964 		(dev->class >> 8) != PCI_CLASS_DISPLAY_VGA) {
965 		if (r->set(pirq_router_dev, dev, pirq, newirq)) {
966 			eisa_set_level_irq(newirq);
967 			msg = "assigned";
968 			irq = newirq;
969 		}
970 	}
971 
972 	if (!irq) {
973 		if (newirq && mask == (1 << newirq)) {
974 			msg = "guessed";
975 			irq = newirq;
976 		} else {
977 			dev_dbg(&dev->dev, "can't route interrupt\n");
978 			return 0;
979 		}
980 	}
981 	dev_info(&dev->dev, "%s PCI INT %c -> IRQ %d\n", msg, 'A' + pin, irq);
982 
983 	/* Update IRQ for all devices with the same pirq value */
984 	while ((dev2 = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev2)) != NULL) {
985 		pci_read_config_byte(dev2, PCI_INTERRUPT_PIN, &pin);
986 		if (!pin)
987 			continue;
988 		pin--;
989 		info = pirq_get_info(dev2);
990 		if (!info)
991 			continue;
992 		if (info->irq[pin].link == pirq) {
993 			/*
994 			 * We refuse to override the dev->irq
995 			 * information. Give a warning!
996 			 */
997 			if (dev2->irq && dev2->irq != irq && \
998 			(!(pci_probe & PCI_USE_PIRQ_MASK) || \
999 			((1 << dev2->irq) & mask))) {
1000 #ifndef CONFIG_PCI_MSI
1001 				dev_info(&dev2->dev, "IRQ routing conflict: "
1002 					 "have IRQ %d, want IRQ %d\n",
1003 					 dev2->irq, irq);
1004 #endif
1005 				continue;
1006 			}
1007 			dev2->irq = irq;
1008 			pirq_penalty[irq]++;
1009 			if (dev != dev2)
1010 				dev_info(&dev->dev, "sharing IRQ %d with %s\n",
1011 					 irq, pci_name(dev2));
1012 		}
1013 	}
1014 	return 1;
1015 }
1016 
1017 static void __init pcibios_fixup_irqs(void)
1018 {
1019 	struct pci_dev *dev = NULL;
1020 	u8 pin;
1021 
1022 	DBG(KERN_DEBUG "PCI: IRQ fixup\n");
1023 	while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
1024 		/*
1025 		 * If the BIOS has set an out of range IRQ number, just
1026 		 * ignore it.  Also keep track of which IRQ's are
1027 		 * already in use.
1028 		 */
1029 		if (dev->irq >= 16) {
1030 			dev_dbg(&dev->dev, "ignoring bogus IRQ %d\n", dev->irq);
1031 			dev->irq = 0;
1032 		}
1033 		/*
1034 		 * If the IRQ is already assigned to a PCI device,
1035 		 * ignore its ISA use penalty
1036 		 */
1037 		if (pirq_penalty[dev->irq] >= 100 &&
1038 				pirq_penalty[dev->irq] < 100000)
1039 			pirq_penalty[dev->irq] = 0;
1040 		pirq_penalty[dev->irq]++;
1041 	}
1042 
1043 	dev = NULL;
1044 	while ((dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev)) != NULL) {
1045 		pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
1046 #ifdef CONFIG_X86_IO_APIC
1047 		/*
1048 		 * Recalculate IRQ numbers if we use the I/O APIC.
1049 		 */
1050 		if (io_apic_assign_pci_irqs) {
1051 			int irq;
1052 
1053 			if (!pin)
1054 				continue;
1055 
1056 			/*
1057 			 * interrupt pins are numbered starting from 1
1058 			 */
1059 			pin--;
1060 			irq = IO_APIC_get_PCI_irq_vector(dev->bus->number,
1061 				PCI_SLOT(dev->devfn), pin);
1062 			/*
1063 			 * Busses behind bridges are typically not listed in the
1064 			 * MP-table.  In this case we have to look up the IRQ
1065 			 * based on the parent bus, parent slot, and pin number.
1066 			 * The SMP code detects such bridged busses itself so we
1067 			 * should get into this branch reliably.
1068 			 */
1069 			if (irq < 0 && dev->bus->parent) {
1070 				/* go back to the bridge */
1071 				struct pci_dev *bridge = dev->bus->self;
1072 				int bus;
1073 
1074 				pin = (pin + PCI_SLOT(dev->devfn)) % 4;
1075 				bus = bridge->bus->number;
1076 				irq = IO_APIC_get_PCI_irq_vector(bus,
1077 						PCI_SLOT(bridge->devfn), pin);
1078 				if (irq >= 0)
1079 					dev_warn(&dev->dev,
1080 						"using bridge %s INT %c to "
1081 							"get IRQ %d\n",
1082 						 pci_name(bridge),
1083 						 'A' + pin, irq);
1084 			}
1085 			if (irq >= 0) {
1086 				dev_info(&dev->dev,
1087 					"PCI->APIC IRQ transform: INT %c "
1088 						"-> IRQ %d\n",
1089 					'A' + pin, irq);
1090 				dev->irq = irq;
1091 			}
1092 		}
1093 #endif
1094 		/*
1095 		 * Still no IRQ? Try to lookup one...
1096 		 */
1097 		if (pin && !dev->irq)
1098 			pcibios_lookup_irq(dev, 0);
1099 	}
1100 }
1101 
1102 /*
1103  * Work around broken HP Pavilion Notebooks which assign USB to
1104  * IRQ 9 even though it is actually wired to IRQ 11
1105  */
1106 static int __init fix_broken_hp_bios_irq9(const struct dmi_system_id *d)
1107 {
1108 	if (!broken_hp_bios_irq9) {
1109 		broken_hp_bios_irq9 = 1;
1110 		printk(KERN_INFO "%s detected - fixing broken IRQ routing\n",
1111 			d->ident);
1112 	}
1113 	return 0;
1114 }
1115 
1116 /*
1117  * Work around broken Acer TravelMate 360 Notebooks which assign
1118  * Cardbus to IRQ 11 even though it is actually wired to IRQ 10
1119  */
1120 static int __init fix_acer_tm360_irqrouting(const struct dmi_system_id *d)
1121 {
1122 	if (!acer_tm360_irqrouting) {
1123 		acer_tm360_irqrouting = 1;
1124 		printk(KERN_INFO "%s detected - fixing broken IRQ routing\n",
1125 			d->ident);
1126 	}
1127 	return 0;
1128 }
1129 
1130 static struct dmi_system_id __initdata pciirq_dmi_table[] = {
1131 	{
1132 		.callback = fix_broken_hp_bios_irq9,
1133 		.ident = "HP Pavilion N5400 Series Laptop",
1134 		.matches = {
1135 			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1136 			DMI_MATCH(DMI_BIOS_VERSION, "GE.M1.03"),
1137 			DMI_MATCH(DMI_PRODUCT_VERSION,
1138 				"HP Pavilion Notebook Model GE"),
1139 			DMI_MATCH(DMI_BOARD_VERSION, "OmniBook N32N-736"),
1140 		},
1141 	},
1142 	{
1143 		.callback = fix_acer_tm360_irqrouting,
1144 		.ident = "Acer TravelMate 36x Laptop",
1145 		.matches = {
1146 			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
1147 			DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 360"),
1148 		},
1149 	},
1150 	{ }
1151 };
1152 
1153 int __init pcibios_irq_init(void)
1154 {
1155 	DBG(KERN_DEBUG "PCI: IRQ init\n");
1156 
1157 	if (pcibios_enable_irq || raw_pci_ops == NULL)
1158 		return 0;
1159 
1160 	dmi_check_system(pciirq_dmi_table);
1161 
1162 	pirq_table = pirq_find_routing_table();
1163 
1164 #ifdef CONFIG_PCI_BIOS
1165 	if (!pirq_table && (pci_probe & PCI_BIOS_IRQ_SCAN))
1166 		pirq_table = pcibios_get_irq_routing_table();
1167 #endif
1168 	if (pirq_table) {
1169 		pirq_peer_trick();
1170 		pirq_find_router(&pirq_router);
1171 		if (pirq_table->exclusive_irqs) {
1172 			int i;
1173 			for (i = 0; i < 16; i++)
1174 				if (!(pirq_table->exclusive_irqs & (1 << i)))
1175 					pirq_penalty[i] += 100;
1176 		}
1177 		/*
1178 		 * If we're using the I/O APIC, avoid using the PCI IRQ
1179 		 * routing table
1180 		 */
1181 		if (io_apic_assign_pci_irqs)
1182 			pirq_table = NULL;
1183 	}
1184 
1185 	pcibios_enable_irq = pirq_enable_irq;
1186 
1187 	pcibios_fixup_irqs();
1188 	return 0;
1189 }
1190 
1191 static void pirq_penalize_isa_irq(int irq, int active)
1192 {
1193 	/*
1194 	 *  If any ISAPnP device reports an IRQ in its list of possible
1195 	 *  IRQ's, we try to avoid assigning it to PCI devices.
1196 	 */
1197 	if (irq < 16) {
1198 		if (active)
1199 			pirq_penalty[irq] += 1000;
1200 		else
1201 			pirq_penalty[irq] += 100;
1202 	}
1203 }
1204 
1205 void pcibios_penalize_isa_irq(int irq, int active)
1206 {
1207 #ifdef CONFIG_ACPI
1208 	if (!acpi_noirq)
1209 		acpi_penalize_isa_irq(irq, active);
1210 	else
1211 #endif
1212 		pirq_penalize_isa_irq(irq, active);
1213 }
1214 
1215 static int pirq_enable_irq(struct pci_dev *dev)
1216 {
1217 	u8 pin;
1218 	struct pci_dev *temp_dev;
1219 
1220 	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
1221 	if (pin && !pcibios_lookup_irq(dev, 1) && !dev->irq) {
1222 		char *msg = "";
1223 
1224 		pin--; /* interrupt pins are numbered starting from 1 */
1225 
1226 		if (io_apic_assign_pci_irqs) {
1227 			int irq;
1228 
1229 			irq = IO_APIC_get_PCI_irq_vector(dev->bus->number, PCI_SLOT(dev->devfn), pin);
1230 			/*
1231 			 * Busses behind bridges are typically not listed in the MP-table.
1232 			 * In this case we have to look up the IRQ based on the parent bus,
1233 			 * parent slot, and pin number. The SMP code detects such bridged
1234 			 * busses itself so we should get into this branch reliably.
1235 			 */
1236 			temp_dev = dev;
1237 			while (irq < 0 && dev->bus->parent) { /* go back to the bridge */
1238 				struct pci_dev *bridge = dev->bus->self;
1239 
1240 				pin = (pin + PCI_SLOT(dev->devfn)) % 4;
1241 				irq = IO_APIC_get_PCI_irq_vector(bridge->bus->number,
1242 						PCI_SLOT(bridge->devfn), pin);
1243 				if (irq >= 0)
1244 					dev_warn(&dev->dev, "using bridge %s "
1245 						 "INT %c to get IRQ %d\n",
1246 						 pci_name(bridge), 'A' + pin,
1247 						 irq);
1248 				dev = bridge;
1249 			}
1250 			dev = temp_dev;
1251 			if (irq >= 0) {
1252 				dev_info(&dev->dev, "PCI->APIC IRQ transform: "
1253 					 "INT %c -> IRQ %d\n", 'A' + pin, irq);
1254 				dev->irq = irq;
1255 				return 0;
1256 			} else
1257 				msg = "; probably buggy MP table";
1258 		} else if (pci_probe & PCI_BIOS_IRQ_SCAN)
1259 			msg = "";
1260 		else
1261 			msg = "; please try using pci=biosirq";
1262 
1263 		/*
1264 		 * With IDE legacy devices the IRQ lookup failure is not
1265 		 * a problem..
1266 		 */
1267 		if (dev->class >> 8 == PCI_CLASS_STORAGE_IDE &&
1268 				!(dev->class & 0x5))
1269 			return 0;
1270 
1271 		dev_warn(&dev->dev, "can't find IRQ for PCI INT %c%s\n",
1272 			 'A' + pin, msg);
1273 	}
1274 	return 0;
1275 }
1276