xref: /openbmc/linux/arch/x86/pci/irq.c (revision 9470114d)
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 <linux/spinlock.h>
17 #include <asm/io_apic.h>
18 #include <linux/irq.h>
19 #include <linux/acpi.h>
20 
21 #include <asm/i8259.h>
22 #include <asm/pc-conf-reg.h>
23 #include <asm/pci_x86.h>
24 
25 #define PIRQ_SIGNATURE	(('$' << 0) + ('P' << 8) + ('I' << 16) + ('R' << 24))
26 #define PIRQ_VERSION 0x0100
27 
28 #define IRT_SIGNATURE	(('$' << 0) + ('I' << 8) + ('R' << 16) + ('T' << 24))
29 
30 static int broken_hp_bios_irq9;
31 static int acer_tm360_irqrouting;
32 
33 static struct irq_routing_table *pirq_table;
34 
35 static int pirq_enable_irq(struct pci_dev *dev);
36 static void pirq_disable_irq(struct pci_dev *dev);
37 
38 /*
39  * Never use: 0, 1, 2 (timer, keyboard, and cascade)
40  * Avoid using: 13, 14 and 15 (FP error and IDE).
41  * Penalize: 3, 4, 6, 7, 12 (known ISA uses: serial, floppy, parallel and mouse)
42  */
43 unsigned int pcibios_irq_mask = 0xfff8;
44 
45 static int pirq_penalty[16] = {
46 	1000000, 1000000, 1000000, 1000, 1000, 0, 1000, 1000,
47 	0, 0, 0, 0, 1000, 100000, 100000, 100000
48 };
49 
50 struct irq_router {
51 	char *name;
52 	u16 vendor, device;
53 	int (*get)(struct pci_dev *router, struct pci_dev *dev, int pirq);
54 	int (*set)(struct pci_dev *router, struct pci_dev *dev, int pirq,
55 		int new);
56 	int (*lvl)(struct pci_dev *router, struct pci_dev *dev, int pirq,
57 		int irq);
58 };
59 
60 struct irq_router_handler {
61 	u16 vendor;
62 	int (*probe)(struct irq_router *r, struct pci_dev *router, u16 device);
63 };
64 
65 int (*pcibios_enable_irq)(struct pci_dev *dev) = pirq_enable_irq;
66 void (*pcibios_disable_irq)(struct pci_dev *dev) = pirq_disable_irq;
67 
68 /*
69  *  Check passed address for the PCI IRQ Routing Table signature
70  *  and perform checksum verification.
71  */
72 
73 static inline struct irq_routing_table *pirq_check_routing_table(u8 *addr,
74 								 u8 *limit)
75 {
76 	struct irq_routing_table *rt;
77 	int i;
78 	u8 sum;
79 
80 	rt = (struct irq_routing_table *)addr;
81 	if (rt->signature != PIRQ_SIGNATURE ||
82 	    rt->version != PIRQ_VERSION ||
83 	    rt->size % 16 ||
84 	    rt->size < sizeof(struct irq_routing_table) ||
85 	    (limit && rt->size > limit - addr))
86 		return NULL;
87 	sum = 0;
88 	for (i = 0; i < rt->size; i++)
89 		sum += addr[i];
90 	if (!sum) {
91 		DBG(KERN_DEBUG "PCI: Interrupt Routing Table found at 0x%lx\n",
92 		    __pa(rt));
93 		return rt;
94 	}
95 	return NULL;
96 }
97 
98 /*
99  * Handle the $IRT PCI IRQ Routing Table format used by AMI for its BCP
100  * (BIOS Configuration Program) external tool meant for tweaking BIOS
101  * structures without the need to rebuild it from sources.  The $IRT
102  * format has been invented by AMI before Microsoft has come up with its
103  * $PIR format and a $IRT table is therefore there in some systems that
104  * lack a $PIR table.
105  *
106  * It uses the same PCI BIOS 2.1 format for interrupt routing entries
107  * themselves but has a different simpler header prepended instead,
108  * occupying 8 bytes, where a `$IRT' signature is followed by one byte
109  * specifying the total number of interrupt routing entries allocated in
110  * the table, then one byte specifying the actual number of entries used
111  * (which the BCP tool can take advantage of when modifying the table),
112  * and finally a 16-bit word giving the IRQs devoted exclusively to PCI.
113  * Unlike with the $PIR table there is no alignment guarantee.
114  *
115  * Given the similarity of the two formats the $IRT one is trivial to
116  * convert to the $PIR one, which we do here, except that obviously we
117  * have no information as to the router device to use, but we can handle
118  * it by matching PCI device IDs actually seen on the bus against ones
119  * that our individual routers recognise.
120  *
121  * Reportedly there is another $IRT table format where a 16-bit word
122  * follows the header instead that points to interrupt routing entries
123  * in a $PIR table provided elsewhere.  In that case this code will not
124  * be reached though as the $PIR table will have been chosen instead.
125  */
126 static inline struct irq_routing_table *pirq_convert_irt_table(u8 *addr,
127 							       u8 *limit)
128 {
129 	struct irt_routing_table *ir;
130 	struct irq_routing_table *rt;
131 	u16 size;
132 	u8 sum;
133 	int i;
134 
135 	ir = (struct irt_routing_table *)addr;
136 	if (ir->signature != IRT_SIGNATURE || !ir->used || ir->size < ir->used)
137 		return NULL;
138 
139 	size = struct_size(ir, slots, ir->used);
140 	if (size > limit - addr)
141 		return NULL;
142 
143 	DBG(KERN_DEBUG "PCI: $IRT Interrupt Routing Table found at 0x%lx\n",
144 	    __pa(ir));
145 
146 	size = struct_size(rt, slots, ir->used);
147 	rt = kzalloc(size, GFP_KERNEL);
148 	if (!rt)
149 		return NULL;
150 
151 	rt->signature = PIRQ_SIGNATURE;
152 	rt->version = PIRQ_VERSION;
153 	rt->size = size;
154 	rt->exclusive_irqs = ir->exclusive_irqs;
155 	for (i = 0; i < ir->used; i++)
156 		rt->slots[i] = ir->slots[i];
157 
158 	addr = (u8 *)rt;
159 	sum = 0;
160 	for (i = 0; i < size; i++)
161 		sum += addr[i];
162 	rt->checksum = -sum;
163 
164 	return rt;
165 }
166 
167 /*
168  *  Search 0xf0000 -- 0xfffff for the PCI IRQ Routing Table.
169  */
170 
171 static struct irq_routing_table * __init pirq_find_routing_table(void)
172 {
173 	u8 * const bios_start = (u8 *)__va(0xf0000);
174 	u8 * const bios_end = (u8 *)__va(0x100000);
175 	u8 *addr;
176 	struct irq_routing_table *rt;
177 
178 	if (pirq_table_addr) {
179 		rt = pirq_check_routing_table((u8 *)__va(pirq_table_addr),
180 					      NULL);
181 		if (rt)
182 			return rt;
183 		printk(KERN_WARNING "PCI: PIRQ table NOT found at pirqaddr\n");
184 	}
185 	for (addr = bios_start;
186 	     addr < bios_end - sizeof(struct irq_routing_table);
187 	     addr += 16) {
188 		rt = pirq_check_routing_table(addr, bios_end);
189 		if (rt)
190 			return rt;
191 	}
192 	for (addr = bios_start;
193 	     addr < bios_end - sizeof(struct irt_routing_table);
194 	     addr++) {
195 		rt = pirq_convert_irt_table(addr, bios_end);
196 		if (rt)
197 			return rt;
198 	}
199 	return NULL;
200 }
201 
202 /*
203  *  If we have a IRQ routing table, use it to search for peer host
204  *  bridges.  It's a gross hack, but since there are no other known
205  *  ways how to get a list of buses, we have to go this way.
206  */
207 
208 static void __init pirq_peer_trick(void)
209 {
210 	struct irq_routing_table *rt = pirq_table;
211 	u8 busmap[256];
212 	int i;
213 	struct irq_info *e;
214 
215 	memset(busmap, 0, sizeof(busmap));
216 	for (i = 0; i < (rt->size - sizeof(struct irq_routing_table)) / sizeof(struct irq_info); i++) {
217 		e = &rt->slots[i];
218 #ifdef DEBUG
219 		{
220 			int j;
221 			DBG(KERN_DEBUG "%02x:%02x.%x slot=%02x",
222 			    e->bus, e->devfn / 8, e->devfn % 8, e->slot);
223 			for (j = 0; j < 4; j++)
224 				DBG(" %d:%02x/%04x", j, e->irq[j].link, e->irq[j].bitmap);
225 			DBG("\n");
226 		}
227 #endif
228 		busmap[e->bus] = 1;
229 	}
230 	for (i = 1; i < 256; i++) {
231 		if (!busmap[i] || pci_find_bus(0, i))
232 			continue;
233 		pcibios_scan_root(i);
234 	}
235 	pcibios_last_bus = -1;
236 }
237 
238 /*
239  *  Code for querying and setting of IRQ routes on various interrupt routers.
240  *  PIC Edge/Level Control Registers (ELCR) 0x4d0 & 0x4d1.
241  */
242 
243 void elcr_set_level_irq(unsigned int irq)
244 {
245 	unsigned char mask = 1 << (irq & 7);
246 	unsigned int port = PIC_ELCR1 + (irq >> 3);
247 	unsigned char val;
248 	static u16 elcr_irq_mask;
249 
250 	if (irq >= 16 || (1 << irq) & elcr_irq_mask)
251 		return;
252 
253 	elcr_irq_mask |= (1 << irq);
254 	printk(KERN_DEBUG "PCI: setting IRQ %u as level-triggered\n", irq);
255 	val = inb(port);
256 	if (!(val & mask)) {
257 		DBG(KERN_DEBUG " -> edge");
258 		outb(val | mask, port);
259 	}
260 }
261 
262 /*
263  *	PIRQ routing for the M1487 ISA Bus Controller (IBC) ASIC used
264  *	with the ALi FinALi 486 chipset.  The IBC is not decoded in the
265  *	PCI configuration space, so we identify it by the accompanying
266  *	M1489 Cache-Memory PCI Controller (CMP) ASIC.
267  *
268  *	There are four 4-bit mappings provided, spread across two PCI
269  *	INTx Routing Table Mapping Registers, available in the port I/O
270  *	space accessible indirectly via the index/data register pair at
271  *	0x22/0x23, located at indices 0x42 and 0x43 for the INT1/INT2
272  *	and INT3/INT4 lines respectively.  The INT1/INT3 and INT2/INT4
273  *	lines are mapped in the low and the high 4-bit nibble of the
274  *	corresponding register as follows:
275  *
276  *	0000 : Disabled
277  *	0001 : IRQ9
278  *	0010 : IRQ3
279  *	0011 : IRQ10
280  *	0100 : IRQ4
281  *	0101 : IRQ5
282  *	0110 : IRQ7
283  *	0111 : IRQ6
284  *	1000 : Reserved
285  *	1001 : IRQ11
286  *	1010 : Reserved
287  *	1011 : IRQ12
288  *	1100 : Reserved
289  *	1101 : IRQ14
290  *	1110 : Reserved
291  *	1111 : IRQ15
292  *
293  *	In addition to the usual ELCR register pair there is a separate
294  *	PCI INTx Sensitivity Register at index 0x44 in the same port I/O
295  *	space, whose bits 3:0 select the trigger mode for INT[4:1] lines
296  *	respectively.  Any bit set to 1 causes interrupts coming on the
297  *	corresponding line to be passed to ISA as edge-triggered and
298  *	otherwise they are passed as level-triggered.  Manufacturer's
299  *	documentation says this register has to be set consistently with
300  *	the relevant ELCR register.
301  *
302  *	Accesses to the port I/O space concerned here need to be unlocked
303  *	by writing the value of 0xc5 to the Lock Register at index 0x03
304  *	beforehand.  Any other value written to said register prevents
305  *	further accesses from reaching the register file, except for the
306  *	Lock Register being written with 0xc5 again.
307  *
308  *	References:
309  *
310  *	"M1489/M1487: 486 PCI Chip Set", Version 1.2, Acer Laboratories
311  *	Inc., July 1997
312  */
313 
314 #define PC_CONF_FINALI_LOCK		0x03u
315 #define PC_CONF_FINALI_PCI_INTX_RT1	0x42u
316 #define PC_CONF_FINALI_PCI_INTX_RT2	0x43u
317 #define PC_CONF_FINALI_PCI_INTX_SENS	0x44u
318 
319 #define PC_CONF_FINALI_LOCK_KEY		0xc5u
320 
321 static u8 read_pc_conf_nybble(u8 base, u8 index)
322 {
323 	u8 reg = base + (index >> 1);
324 	u8 x;
325 
326 	x = pc_conf_get(reg);
327 	return index & 1 ? x >> 4 : x & 0xf;
328 }
329 
330 static void write_pc_conf_nybble(u8 base, u8 index, u8 val)
331 {
332 	u8 reg = base + (index >> 1);
333 	u8 x;
334 
335 	x = pc_conf_get(reg);
336 	x = index & 1 ? (x & 0x0f) | (val << 4) : (x & 0xf0) | val;
337 	pc_conf_set(reg, x);
338 }
339 
340 /*
341  * FinALi pirq rules are as follows:
342  *
343  * - bit 0 selects between INTx Routing Table Mapping Registers,
344  *
345  * - bit 3 selects the nibble within the INTx Routing Table Mapping Register,
346  *
347  * - bits 7:4 map to bits 3:0 of the PCI INTx Sensitivity Register.
348  */
349 static int pirq_finali_get(struct pci_dev *router, struct pci_dev *dev,
350 			   int pirq)
351 {
352 	static const u8 irqmap[16] = {
353 		0, 9, 3, 10, 4, 5, 7, 6, 0, 11, 0, 12, 0, 14, 0, 15
354 	};
355 	unsigned long flags;
356 	u8 index;
357 	u8 x;
358 
359 	index = (pirq & 1) << 1 | (pirq & 8) >> 3;
360 	raw_spin_lock_irqsave(&pc_conf_lock, flags);
361 	pc_conf_set(PC_CONF_FINALI_LOCK, PC_CONF_FINALI_LOCK_KEY);
362 	x = irqmap[read_pc_conf_nybble(PC_CONF_FINALI_PCI_INTX_RT1, index)];
363 	pc_conf_set(PC_CONF_FINALI_LOCK, 0);
364 	raw_spin_unlock_irqrestore(&pc_conf_lock, flags);
365 	return x;
366 }
367 
368 static int pirq_finali_set(struct pci_dev *router, struct pci_dev *dev,
369 			   int pirq, int irq)
370 {
371 	static const u8 irqmap[16] = {
372 		0, 0, 0, 2, 4, 5, 7, 6, 0, 1, 3, 9, 11, 0, 13, 15
373 	};
374 	u8 val = irqmap[irq];
375 	unsigned long flags;
376 	u8 index;
377 
378 	if (!val)
379 		return 0;
380 
381 	index = (pirq & 1) << 1 | (pirq & 8) >> 3;
382 	raw_spin_lock_irqsave(&pc_conf_lock, flags);
383 	pc_conf_set(PC_CONF_FINALI_LOCK, PC_CONF_FINALI_LOCK_KEY);
384 	write_pc_conf_nybble(PC_CONF_FINALI_PCI_INTX_RT1, index, val);
385 	pc_conf_set(PC_CONF_FINALI_LOCK, 0);
386 	raw_spin_unlock_irqrestore(&pc_conf_lock, flags);
387 	return 1;
388 }
389 
390 static int pirq_finali_lvl(struct pci_dev *router, struct pci_dev *dev,
391 			   int pirq, int irq)
392 {
393 	u8 mask = ~((pirq & 0xf0u) >> 4);
394 	unsigned long flags;
395 	u8 trig;
396 
397 	elcr_set_level_irq(irq);
398 	raw_spin_lock_irqsave(&pc_conf_lock, flags);
399 	pc_conf_set(PC_CONF_FINALI_LOCK, PC_CONF_FINALI_LOCK_KEY);
400 	trig = pc_conf_get(PC_CONF_FINALI_PCI_INTX_SENS);
401 	trig &= mask;
402 	pc_conf_set(PC_CONF_FINALI_PCI_INTX_SENS, trig);
403 	pc_conf_set(PC_CONF_FINALI_LOCK, 0);
404 	raw_spin_unlock_irqrestore(&pc_conf_lock, flags);
405 	return 1;
406 }
407 
408 /*
409  * Common IRQ routing practice: nibbles in config space,
410  * offset by some magic constant.
411  */
412 static unsigned int read_config_nybble(struct pci_dev *router, unsigned offset, unsigned nr)
413 {
414 	u8 x;
415 	unsigned reg = offset + (nr >> 1);
416 
417 	pci_read_config_byte(router, reg, &x);
418 	return (nr & 1) ? (x >> 4) : (x & 0xf);
419 }
420 
421 static void write_config_nybble(struct pci_dev *router, unsigned offset,
422 	unsigned nr, unsigned int val)
423 {
424 	u8 x;
425 	unsigned reg = offset + (nr >> 1);
426 
427 	pci_read_config_byte(router, reg, &x);
428 	x = (nr & 1) ? ((x & 0x0f) | (val << 4)) : ((x & 0xf0) | val);
429 	pci_write_config_byte(router, reg, x);
430 }
431 
432 /*
433  * ALI pirq entries are damn ugly, and completely undocumented.
434  * This has been figured out from pirq tables, and it's not a pretty
435  * picture.
436  */
437 static int pirq_ali_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
438 {
439 	static const unsigned char irqmap[16] = { 0, 9, 3, 10, 4, 5, 7, 6, 1, 11, 0, 12, 0, 14, 0, 15 };
440 
441 	WARN_ON_ONCE(pirq > 16);
442 	return irqmap[read_config_nybble(router, 0x48, pirq-1)];
443 }
444 
445 static int pirq_ali_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
446 {
447 	static const unsigned char irqmap[16] = { 0, 8, 0, 2, 4, 5, 7, 6, 0, 1, 3, 9, 11, 0, 13, 15 };
448 	unsigned int val = irqmap[irq];
449 
450 	WARN_ON_ONCE(pirq > 16);
451 	if (val) {
452 		write_config_nybble(router, 0x48, pirq-1, val);
453 		return 1;
454 	}
455 	return 0;
456 }
457 
458 /*
459  *	PIRQ routing for the 82374EB/82374SB EISA System Component (ESC)
460  *	ASIC used with the Intel 82420 and 82430 PCIsets.  The ESC is not
461  *	decoded in the PCI configuration space, so we identify it by the
462  *	accompanying 82375EB/82375SB PCI-EISA Bridge (PCEB) ASIC.
463  *
464  *	There are four PIRQ Route Control registers, available in the
465  *	port I/O space accessible indirectly via the index/data register
466  *	pair at 0x22/0x23, located at indices 0x60/0x61/0x62/0x63 for the
467  *	PIRQ0/1/2/3# lines respectively.  The semantics is the same as
468  *	with the PIIX router.
469  *
470  *	Accesses to the port I/O space concerned here need to be unlocked
471  *	by writing the value of 0x0f to the ESC ID Register at index 0x02
472  *	beforehand.  Any other value written to said register prevents
473  *	further accesses from reaching the register file, except for the
474  *	ESC ID Register being written with 0x0f again.
475  *
476  *	References:
477  *
478  *	"82374EB/82374SB EISA System Component (ESC)", Intel Corporation,
479  *	Order Number: 290476-004, March 1996
480  *
481  *	"82375EB/82375SB PCI-EISA Bridge (PCEB)", Intel Corporation, Order
482  *	Number: 290477-004, March 1996
483  */
484 
485 #define PC_CONF_I82374_ESC_ID			0x02u
486 #define PC_CONF_I82374_PIRQ_ROUTE_CONTROL	0x60u
487 
488 #define PC_CONF_I82374_ESC_ID_KEY		0x0fu
489 
490 static int pirq_esc_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
491 {
492 	unsigned long flags;
493 	int reg;
494 	u8 x;
495 
496 	reg = pirq;
497 	if (reg >= 1 && reg <= 4)
498 		reg += PC_CONF_I82374_PIRQ_ROUTE_CONTROL - 1;
499 
500 	raw_spin_lock_irqsave(&pc_conf_lock, flags);
501 	pc_conf_set(PC_CONF_I82374_ESC_ID, PC_CONF_I82374_ESC_ID_KEY);
502 	x = pc_conf_get(reg);
503 	pc_conf_set(PC_CONF_I82374_ESC_ID, 0);
504 	raw_spin_unlock_irqrestore(&pc_conf_lock, flags);
505 	return (x < 16) ? x : 0;
506 }
507 
508 static int pirq_esc_set(struct pci_dev *router, struct pci_dev *dev, int pirq,
509 		       int irq)
510 {
511 	unsigned long flags;
512 	int reg;
513 
514 	reg = pirq;
515 	if (reg >= 1 && reg <= 4)
516 		reg += PC_CONF_I82374_PIRQ_ROUTE_CONTROL - 1;
517 
518 	raw_spin_lock_irqsave(&pc_conf_lock, flags);
519 	pc_conf_set(PC_CONF_I82374_ESC_ID, PC_CONF_I82374_ESC_ID_KEY);
520 	pc_conf_set(reg, irq);
521 	pc_conf_set(PC_CONF_I82374_ESC_ID, 0);
522 	raw_spin_unlock_irqrestore(&pc_conf_lock, flags);
523 	return 1;
524 }
525 
526 /*
527  * The Intel PIIX4 pirq rules are fairly simple: "pirq" is
528  * just a pointer to the config space.
529  */
530 static int pirq_piix_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
531 {
532 	u8 x;
533 
534 	pci_read_config_byte(router, pirq, &x);
535 	return (x < 16) ? x : 0;
536 }
537 
538 static int pirq_piix_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
539 {
540 	pci_write_config_byte(router, pirq, irq);
541 	return 1;
542 }
543 
544 /*
545  *	PIRQ routing for the 82426EX ISA Bridge (IB) ASIC used with the
546  *	Intel 82420EX PCIset.
547  *
548  *	There are only two PIRQ Route Control registers, available in the
549  *	combined 82425EX/82426EX PCI configuration space, at 0x66 and 0x67
550  *	for the PIRQ0# and PIRQ1# lines respectively.  The semantics is
551  *	the same as with the PIIX router.
552  *
553  *	References:
554  *
555  *	"82420EX PCIset Data Sheet, 82425EX PCI System Controller (PSC)
556  *	and 82426EX ISA Bridge (IB)", Intel Corporation, Order Number:
557  *	290488-004, December 1995
558  */
559 
560 #define PCI_I82426EX_PIRQ_ROUTE_CONTROL	0x66u
561 
562 static int pirq_ib_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
563 {
564 	int reg;
565 	u8 x;
566 
567 	reg = pirq;
568 	if (reg >= 1 && reg <= 2)
569 		reg += PCI_I82426EX_PIRQ_ROUTE_CONTROL - 1;
570 
571 	pci_read_config_byte(router, reg, &x);
572 	return (x < 16) ? x : 0;
573 }
574 
575 static int pirq_ib_set(struct pci_dev *router, struct pci_dev *dev, int pirq,
576 		       int irq)
577 {
578 	int reg;
579 
580 	reg = pirq;
581 	if (reg >= 1 && reg <= 2)
582 		reg += PCI_I82426EX_PIRQ_ROUTE_CONTROL - 1;
583 
584 	pci_write_config_byte(router, reg, irq);
585 	return 1;
586 }
587 
588 /*
589  * The VIA pirq rules are nibble-based, like ALI,
590  * but without the ugly irq number munging.
591  * However, PIRQD is in the upper instead of lower 4 bits.
592  */
593 static int pirq_via_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
594 {
595 	return read_config_nybble(router, 0x55, pirq == 4 ? 5 : pirq);
596 }
597 
598 static int pirq_via_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
599 {
600 	write_config_nybble(router, 0x55, pirq == 4 ? 5 : pirq, irq);
601 	return 1;
602 }
603 
604 /*
605  * The VIA pirq rules are nibble-based, like ALI,
606  * but without the ugly irq number munging.
607  * However, for 82C586, nibble map is different .
608  */
609 static int pirq_via586_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
610 {
611 	static const unsigned int pirqmap[5] = { 3, 2, 5, 1, 1 };
612 
613 	WARN_ON_ONCE(pirq > 5);
614 	return read_config_nybble(router, 0x55, pirqmap[pirq-1]);
615 }
616 
617 static int pirq_via586_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
618 {
619 	static const unsigned int pirqmap[5] = { 3, 2, 5, 1, 1 };
620 
621 	WARN_ON_ONCE(pirq > 5);
622 	write_config_nybble(router, 0x55, pirqmap[pirq-1], irq);
623 	return 1;
624 }
625 
626 /*
627  * ITE 8330G pirq rules are nibble-based
628  * FIXME: pirqmap may be { 1, 0, 3, 2 },
629  * 	  2+3 are both mapped to irq 9 on my system
630  */
631 static int pirq_ite_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
632 {
633 	static const unsigned char pirqmap[4] = { 1, 0, 2, 3 };
634 
635 	WARN_ON_ONCE(pirq > 4);
636 	return read_config_nybble(router, 0x43, pirqmap[pirq-1]);
637 }
638 
639 static int pirq_ite_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
640 {
641 	static const unsigned char pirqmap[4] = { 1, 0, 2, 3 };
642 
643 	WARN_ON_ONCE(pirq > 4);
644 	write_config_nybble(router, 0x43, pirqmap[pirq-1], irq);
645 	return 1;
646 }
647 
648 /*
649  * OPTI: high four bits are nibble pointer..
650  * I wonder what the low bits do?
651  */
652 static int pirq_opti_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
653 {
654 	return read_config_nybble(router, 0xb8, pirq >> 4);
655 }
656 
657 static int pirq_opti_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
658 {
659 	write_config_nybble(router, 0xb8, pirq >> 4, irq);
660 	return 1;
661 }
662 
663 /*
664  * Cyrix: nibble offset 0x5C
665  * 0x5C bits 7:4 is INTB bits 3:0 is INTA
666  * 0x5D bits 7:4 is INTD bits 3:0 is INTC
667  */
668 static int pirq_cyrix_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
669 {
670 	return read_config_nybble(router, 0x5C, (pirq-1)^1);
671 }
672 
673 static int pirq_cyrix_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
674 {
675 	write_config_nybble(router, 0x5C, (pirq-1)^1, irq);
676 	return 1;
677 }
678 
679 
680 /*
681  *	PIRQ routing for the SiS85C497 AT Bus Controller & Megacell (ATM)
682  *	ISA bridge used with the SiS 85C496/497 486 Green PC VESA/ISA/PCI
683  *	Chipset.
684  *
685  *	There are four PCI INTx#-to-IRQ Link registers provided in the
686  *	SiS85C497 part of the peculiar combined 85C496/497 configuration
687  *	space decoded by the SiS85C496 PCI & CPU Memory Controller (PCM)
688  *	host bridge, at 0xc0/0xc1/0xc2/0xc3 respectively for the PCI INT
689  *	A/B/C/D lines.  Bit 7 enables the respective link if set and bits
690  *	3:0 select the 8259A IRQ line as follows:
691  *
692  *	0000 : Reserved
693  *	0001 : Reserved
694  *	0010 : Reserved
695  *	0011 : IRQ3
696  *	0100 : IRQ4
697  *	0101 : IRQ5
698  *	0110 : IRQ6
699  *	0111 : IRQ7
700  *	1000 : Reserved
701  *	1001 : IRQ9
702  *	1010 : IRQ10
703  *	1011 : IRQ11
704  *	1100 : IRQ12
705  *	1101 : Reserved
706  *	1110 : IRQ14
707  *	1111 : IRQ15
708  *
709  *	We avoid using a reserved value for disabled links, hence the
710  *	choice of IRQ15 for that case.
711  *
712  *	References:
713  *
714  *	"486 Green PC VESA/ISA/PCI Chipset, SiS 85C496/497", Rev 3.0,
715  *	Silicon Integrated Systems Corp., July 1995
716  */
717 
718 #define PCI_SIS497_INTA_TO_IRQ_LINK	0xc0u
719 
720 #define PIRQ_SIS497_IRQ_MASK		0x0fu
721 #define PIRQ_SIS497_IRQ_ENABLE		0x80u
722 
723 static int pirq_sis497_get(struct pci_dev *router, struct pci_dev *dev,
724 			   int pirq)
725 {
726 	int reg;
727 	u8 x;
728 
729 	reg = pirq;
730 	if (reg >= 1 && reg <= 4)
731 		reg += PCI_SIS497_INTA_TO_IRQ_LINK - 1;
732 
733 	pci_read_config_byte(router, reg, &x);
734 	return (x & PIRQ_SIS497_IRQ_ENABLE) ? (x & PIRQ_SIS497_IRQ_MASK) : 0;
735 }
736 
737 static int pirq_sis497_set(struct pci_dev *router, struct pci_dev *dev,
738 			   int pirq, int irq)
739 {
740 	int reg;
741 	u8 x;
742 
743 	reg = pirq;
744 	if (reg >= 1 && reg <= 4)
745 		reg += PCI_SIS497_INTA_TO_IRQ_LINK - 1;
746 
747 	pci_read_config_byte(router, reg, &x);
748 	x &= ~(PIRQ_SIS497_IRQ_MASK | PIRQ_SIS497_IRQ_ENABLE);
749 	x |= irq ? (PIRQ_SIS497_IRQ_ENABLE | irq) : PIRQ_SIS497_IRQ_MASK;
750 	pci_write_config_byte(router, reg, x);
751 	return 1;
752 }
753 
754 /*
755  *	PIRQ routing for SiS 85C503 router used in several SiS chipsets.
756  *	We have to deal with the following issues here:
757  *	- vendors have different ideas about the meaning of link values
758  *	- some onboard devices (integrated in the chipset) have special
759  *	  links and are thus routed differently (i.e. not via PCI INTA-INTD)
760  *	- different revision of the router have a different layout for
761  *	  the routing registers, particularly for the onchip devices
762  *
763  *	For all routing registers the common thing is we have one byte
764  *	per routeable link which is defined as:
765  *		 bit 7      IRQ mapping enabled (0) or disabled (1)
766  *		 bits [6:4] reserved (sometimes used for onchip devices)
767  *		 bits [3:0] IRQ to map to
768  *		     allowed: 3-7, 9-12, 14-15
769  *		     reserved: 0, 1, 2, 8, 13
770  *
771  *	The config-space registers located at 0x41/0x42/0x43/0x44 are
772  *	always used to route the normal PCI INT A/B/C/D respectively.
773  *	Apparently there are systems implementing PCI routing table using
774  *	link values 0x01-0x04 and others using 0x41-0x44 for PCI INTA..D.
775  *	We try our best to handle both link mappings.
776  *
777  *	Currently (2003-05-21) it appears most SiS chipsets follow the
778  *	definition of routing registers from the SiS-5595 southbridge.
779  *	According to the SiS 5595 datasheets the revision id's of the
780  *	router (ISA-bridge) should be 0x01 or 0xb0.
781  *
782  *	Furthermore we've also seen lspci dumps with revision 0x00 and 0xb1.
783  *	Looks like these are used in a number of SiS 5xx/6xx/7xx chipsets.
784  *	They seem to work with the current routing code. However there is
785  *	some concern because of the two USB-OHCI HCs (original SiS 5595
786  *	had only one). YMMV.
787  *
788  *	Onchip routing for router rev-id 0x01/0xb0 and probably 0x00/0xb1:
789  *
790  *	0x61:	IDEIRQ:
791  *		bits [6:5] must be written 01
792  *		bit 4 channel-select primary (0), secondary (1)
793  *
794  *	0x62:	USBIRQ:
795  *		bit 6 OHCI function disabled (0), enabled (1)
796  *
797  *	0x6a:	ACPI/SCI IRQ: bits 4-6 reserved
798  *
799  *	0x7e:	Data Acq. Module IRQ - bits 4-6 reserved
800  *
801  *	We support USBIRQ (in addition to INTA-INTD) and keep the
802  *	IDE, ACPI and DAQ routing untouched as set by the BIOS.
803  *
804  *	Currently the only reported exception is the new SiS 65x chipset
805  *	which includes the SiS 69x southbridge. Here we have the 85C503
806  *	router revision 0x04 and there are changes in the register layout
807  *	mostly related to the different USB HCs with USB 2.0 support.
808  *
809  *	Onchip routing for router rev-id 0x04 (try-and-error observation)
810  *
811  *	0x60/0x61/0x62/0x63:	1xEHCI and 3xOHCI (companion) USB-HCs
812  *				bit 6-4 are probably unused, not like 5595
813  */
814 
815 #define PIRQ_SIS503_IRQ_MASK	0x0f
816 #define PIRQ_SIS503_IRQ_DISABLE	0x80
817 #define PIRQ_SIS503_USB_ENABLE	0x40
818 
819 static int pirq_sis503_get(struct pci_dev *router, struct pci_dev *dev,
820 			   int pirq)
821 {
822 	u8 x;
823 	int reg;
824 
825 	reg = pirq;
826 	if (reg >= 0x01 && reg <= 0x04)
827 		reg += 0x40;
828 	pci_read_config_byte(router, reg, &x);
829 	return (x & PIRQ_SIS503_IRQ_DISABLE) ? 0 : (x & PIRQ_SIS503_IRQ_MASK);
830 }
831 
832 static int pirq_sis503_set(struct pci_dev *router, struct pci_dev *dev,
833 			   int pirq, int irq)
834 {
835 	u8 x;
836 	int reg;
837 
838 	reg = pirq;
839 	if (reg >= 0x01 && reg <= 0x04)
840 		reg += 0x40;
841 	pci_read_config_byte(router, reg, &x);
842 	x &= ~(PIRQ_SIS503_IRQ_MASK | PIRQ_SIS503_IRQ_DISABLE);
843 	x |= irq ? irq : PIRQ_SIS503_IRQ_DISABLE;
844 	pci_write_config_byte(router, reg, x);
845 	return 1;
846 }
847 
848 
849 /*
850  * VLSI: nibble offset 0x74 - educated guess due to routing table and
851  *       config space of VLSI 82C534 PCI-bridge/router (1004:0102)
852  *       Tested on HP OmniBook 800 covering PIRQ 1, 2, 4, 8 for onboard
853  *       devices, PIRQ 3 for non-pci(!) soundchip and (untested) PIRQ 6
854  *       for the busbridge to the docking station.
855  */
856 
857 static int pirq_vlsi_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
858 {
859 	WARN_ON_ONCE(pirq >= 9);
860 	if (pirq > 8) {
861 		dev_info(&dev->dev, "VLSI router PIRQ escape (%d)\n", pirq);
862 		return 0;
863 	}
864 	return read_config_nybble(router, 0x74, pirq-1);
865 }
866 
867 static int pirq_vlsi_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
868 {
869 	WARN_ON_ONCE(pirq >= 9);
870 	if (pirq > 8) {
871 		dev_info(&dev->dev, "VLSI router PIRQ escape (%d)\n", pirq);
872 		return 0;
873 	}
874 	write_config_nybble(router, 0x74, pirq-1, irq);
875 	return 1;
876 }
877 
878 /*
879  * ServerWorks: PCI interrupts mapped to system IRQ lines through Index
880  * and Redirect I/O registers (0x0c00 and 0x0c01).  The Index register
881  * format is (PCIIRQ## | 0x10), e.g.: PCIIRQ10=0x1a.  The Redirect
882  * register is a straight binary coding of desired PIC IRQ (low nibble).
883  *
884  * The 'link' value in the PIRQ table is already in the correct format
885  * for the Index register.  There are some special index values:
886  * 0x00 for ACPI (SCI), 0x01 for USB, 0x02 for IDE0, 0x04 for IDE1,
887  * and 0x03 for SMBus.
888  */
889 static int pirq_serverworks_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
890 {
891 	outb(pirq, 0xc00);
892 	return inb(0xc01) & 0xf;
893 }
894 
895 static int pirq_serverworks_set(struct pci_dev *router, struct pci_dev *dev,
896 	int pirq, int irq)
897 {
898 	outb(pirq, 0xc00);
899 	outb(irq, 0xc01);
900 	return 1;
901 }
902 
903 /* Support for AMD756 PCI IRQ Routing
904  * Jhon H. Caicedo <jhcaiced@osso.org.co>
905  * Jun/21/2001 0.2.0 Release, fixed to use "nybble" functions... (jhcaiced)
906  * Jun/19/2001 Alpha Release 0.1.0 (jhcaiced)
907  * The AMD756 pirq rules are nibble-based
908  * offset 0x56 0-3 PIRQA  4-7  PIRQB
909  * offset 0x57 0-3 PIRQC  4-7  PIRQD
910  */
911 static int pirq_amd756_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
912 {
913 	u8 irq;
914 	irq = 0;
915 	if (pirq <= 4)
916 		irq = read_config_nybble(router, 0x56, pirq - 1);
917 	dev_info(&dev->dev,
918 		 "AMD756: dev [%04x:%04x], router PIRQ %d get IRQ %d\n",
919 		 dev->vendor, dev->device, pirq, irq);
920 	return irq;
921 }
922 
923 static int pirq_amd756_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
924 {
925 	dev_info(&dev->dev,
926 		 "AMD756: dev [%04x:%04x], router PIRQ %d set IRQ %d\n",
927 		 dev->vendor, dev->device, pirq, irq);
928 	if (pirq <= 4)
929 		write_config_nybble(router, 0x56, pirq - 1, irq);
930 	return 1;
931 }
932 
933 /*
934  * PicoPower PT86C523
935  */
936 static int pirq_pico_get(struct pci_dev *router, struct pci_dev *dev, int pirq)
937 {
938 	outb(0x10 + ((pirq - 1) >> 1), 0x24);
939 	return ((pirq - 1) & 1) ? (inb(0x26) >> 4) : (inb(0x26) & 0xf);
940 }
941 
942 static int pirq_pico_set(struct pci_dev *router, struct pci_dev *dev, int pirq,
943 			int irq)
944 {
945 	unsigned int x;
946 	outb(0x10 + ((pirq - 1) >> 1), 0x24);
947 	x = inb(0x26);
948 	x = ((pirq - 1) & 1) ? ((x & 0x0f) | (irq << 4)) : ((x & 0xf0) | (irq));
949 	outb(x, 0x26);
950 	return 1;
951 }
952 
953 #ifdef CONFIG_PCI_BIOS
954 
955 static int pirq_bios_set(struct pci_dev *router, struct pci_dev *dev, int pirq, int irq)
956 {
957 	struct pci_dev *bridge;
958 	int pin = pci_get_interrupt_pin(dev, &bridge);
959 	return pcibios_set_irq_routing(bridge, pin - 1, irq);
960 }
961 
962 #endif
963 
964 static __init int intel_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
965 {
966 	static struct pci_device_id __initdata pirq_440gx[] = {
967 		{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443GX_0) },
968 		{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, PCI_DEVICE_ID_INTEL_82443GX_2) },
969 		{ },
970 	};
971 
972 	/* 440GX has a proprietary PIRQ router -- don't use it */
973 	if (pci_dev_present(pirq_440gx))
974 		return 0;
975 
976 	switch (device) {
977 	case PCI_DEVICE_ID_INTEL_82375:
978 		r->name = "PCEB/ESC";
979 		r->get = pirq_esc_get;
980 		r->set = pirq_esc_set;
981 		return 1;
982 	case PCI_DEVICE_ID_INTEL_82371FB_0:
983 	case PCI_DEVICE_ID_INTEL_82371SB_0:
984 	case PCI_DEVICE_ID_INTEL_82371AB_0:
985 	case PCI_DEVICE_ID_INTEL_82371MX:
986 	case PCI_DEVICE_ID_INTEL_82443MX_0:
987 	case PCI_DEVICE_ID_INTEL_82801AA_0:
988 	case PCI_DEVICE_ID_INTEL_82801AB_0:
989 	case PCI_DEVICE_ID_INTEL_82801BA_0:
990 	case PCI_DEVICE_ID_INTEL_82801BA_10:
991 	case PCI_DEVICE_ID_INTEL_82801CA_0:
992 	case PCI_DEVICE_ID_INTEL_82801CA_12:
993 	case PCI_DEVICE_ID_INTEL_82801DB_0:
994 	case PCI_DEVICE_ID_INTEL_82801E_0:
995 	case PCI_DEVICE_ID_INTEL_82801EB_0:
996 	case PCI_DEVICE_ID_INTEL_ESB_1:
997 	case PCI_DEVICE_ID_INTEL_ICH6_0:
998 	case PCI_DEVICE_ID_INTEL_ICH6_1:
999 	case PCI_DEVICE_ID_INTEL_ICH7_0:
1000 	case PCI_DEVICE_ID_INTEL_ICH7_1:
1001 	case PCI_DEVICE_ID_INTEL_ICH7_30:
1002 	case PCI_DEVICE_ID_INTEL_ICH7_31:
1003 	case PCI_DEVICE_ID_INTEL_TGP_LPC:
1004 	case PCI_DEVICE_ID_INTEL_ESB2_0:
1005 	case PCI_DEVICE_ID_INTEL_ICH8_0:
1006 	case PCI_DEVICE_ID_INTEL_ICH8_1:
1007 	case PCI_DEVICE_ID_INTEL_ICH8_2:
1008 	case PCI_DEVICE_ID_INTEL_ICH8_3:
1009 	case PCI_DEVICE_ID_INTEL_ICH8_4:
1010 	case PCI_DEVICE_ID_INTEL_ICH9_0:
1011 	case PCI_DEVICE_ID_INTEL_ICH9_1:
1012 	case PCI_DEVICE_ID_INTEL_ICH9_2:
1013 	case PCI_DEVICE_ID_INTEL_ICH9_3:
1014 	case PCI_DEVICE_ID_INTEL_ICH9_4:
1015 	case PCI_DEVICE_ID_INTEL_ICH9_5:
1016 	case PCI_DEVICE_ID_INTEL_EP80579_0:
1017 	case PCI_DEVICE_ID_INTEL_ICH10_0:
1018 	case PCI_DEVICE_ID_INTEL_ICH10_1:
1019 	case PCI_DEVICE_ID_INTEL_ICH10_2:
1020 	case PCI_DEVICE_ID_INTEL_ICH10_3:
1021 	case PCI_DEVICE_ID_INTEL_PATSBURG_LPC_0:
1022 	case PCI_DEVICE_ID_INTEL_PATSBURG_LPC_1:
1023 		r->name = "PIIX/ICH";
1024 		r->get = pirq_piix_get;
1025 		r->set = pirq_piix_set;
1026 		return 1;
1027 	case PCI_DEVICE_ID_INTEL_82425:
1028 		r->name = "PSC/IB";
1029 		r->get = pirq_ib_get;
1030 		r->set = pirq_ib_set;
1031 		return 1;
1032 	}
1033 
1034 	if ((device >= PCI_DEVICE_ID_INTEL_5_3400_SERIES_LPC_MIN &&
1035 	     device <= PCI_DEVICE_ID_INTEL_5_3400_SERIES_LPC_MAX)
1036 	||  (device >= PCI_DEVICE_ID_INTEL_COUGARPOINT_LPC_MIN &&
1037 	     device <= PCI_DEVICE_ID_INTEL_COUGARPOINT_LPC_MAX)
1038 	||  (device >= PCI_DEVICE_ID_INTEL_DH89XXCC_LPC_MIN &&
1039 	     device <= PCI_DEVICE_ID_INTEL_DH89XXCC_LPC_MAX)
1040 	||  (device >= PCI_DEVICE_ID_INTEL_PANTHERPOINT_LPC_MIN &&
1041 	     device <= PCI_DEVICE_ID_INTEL_PANTHERPOINT_LPC_MAX)) {
1042 		r->name = "PIIX/ICH";
1043 		r->get = pirq_piix_get;
1044 		r->set = pirq_piix_set;
1045 		return 1;
1046 	}
1047 
1048 	return 0;
1049 }
1050 
1051 static __init int via_router_probe(struct irq_router *r,
1052 				struct pci_dev *router, u16 device)
1053 {
1054 	/* FIXME: We should move some of the quirk fixup stuff here */
1055 
1056 	/*
1057 	 * workarounds for some buggy BIOSes
1058 	 */
1059 	if (device == PCI_DEVICE_ID_VIA_82C586_0) {
1060 		switch (router->device) {
1061 		case PCI_DEVICE_ID_VIA_82C686:
1062 			/*
1063 			 * Asus k7m bios wrongly reports 82C686A
1064 			 * as 586-compatible
1065 			 */
1066 			device = PCI_DEVICE_ID_VIA_82C686;
1067 			break;
1068 		case PCI_DEVICE_ID_VIA_8235:
1069 			/**
1070 			 * Asus a7v-x bios wrongly reports 8235
1071 			 * as 586-compatible
1072 			 */
1073 			device = PCI_DEVICE_ID_VIA_8235;
1074 			break;
1075 		case PCI_DEVICE_ID_VIA_8237:
1076 			/**
1077 			 * Asus a7v600 bios wrongly reports 8237
1078 			 * as 586-compatible
1079 			 */
1080 			device = PCI_DEVICE_ID_VIA_8237;
1081 			break;
1082 		}
1083 	}
1084 
1085 	switch (device) {
1086 	case PCI_DEVICE_ID_VIA_82C586_0:
1087 		r->name = "VIA";
1088 		r->get = pirq_via586_get;
1089 		r->set = pirq_via586_set;
1090 		return 1;
1091 	case PCI_DEVICE_ID_VIA_82C596:
1092 	case PCI_DEVICE_ID_VIA_82C686:
1093 	case PCI_DEVICE_ID_VIA_8231:
1094 	case PCI_DEVICE_ID_VIA_8233A:
1095 	case PCI_DEVICE_ID_VIA_8235:
1096 	case PCI_DEVICE_ID_VIA_8237:
1097 		/* FIXME: add new ones for 8233/5 */
1098 		r->name = "VIA";
1099 		r->get = pirq_via_get;
1100 		r->set = pirq_via_set;
1101 		return 1;
1102 	}
1103 	return 0;
1104 }
1105 
1106 static __init int vlsi_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
1107 {
1108 	switch (device) {
1109 	case PCI_DEVICE_ID_VLSI_82C534:
1110 		r->name = "VLSI 82C534";
1111 		r->get = pirq_vlsi_get;
1112 		r->set = pirq_vlsi_set;
1113 		return 1;
1114 	}
1115 	return 0;
1116 }
1117 
1118 
1119 static __init int serverworks_router_probe(struct irq_router *r,
1120 		struct pci_dev *router, u16 device)
1121 {
1122 	switch (device) {
1123 	case PCI_DEVICE_ID_SERVERWORKS_OSB4:
1124 	case PCI_DEVICE_ID_SERVERWORKS_CSB5:
1125 		r->name = "ServerWorks";
1126 		r->get = pirq_serverworks_get;
1127 		r->set = pirq_serverworks_set;
1128 		return 1;
1129 	}
1130 	return 0;
1131 }
1132 
1133 static __init int sis_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
1134 {
1135 	switch (device) {
1136 	case PCI_DEVICE_ID_SI_496:
1137 		r->name = "SiS85C497";
1138 		r->get = pirq_sis497_get;
1139 		r->set = pirq_sis497_set;
1140 		return 1;
1141 	case PCI_DEVICE_ID_SI_503:
1142 		r->name = "SiS85C503";
1143 		r->get = pirq_sis503_get;
1144 		r->set = pirq_sis503_set;
1145 		return 1;
1146 	}
1147 	return 0;
1148 }
1149 
1150 static __init int cyrix_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
1151 {
1152 	switch (device) {
1153 	case PCI_DEVICE_ID_CYRIX_5520:
1154 		r->name = "NatSemi";
1155 		r->get = pirq_cyrix_get;
1156 		r->set = pirq_cyrix_set;
1157 		return 1;
1158 	}
1159 	return 0;
1160 }
1161 
1162 static __init int opti_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
1163 {
1164 	switch (device) {
1165 	case PCI_DEVICE_ID_OPTI_82C700:
1166 		r->name = "OPTI";
1167 		r->get = pirq_opti_get;
1168 		r->set = pirq_opti_set;
1169 		return 1;
1170 	}
1171 	return 0;
1172 }
1173 
1174 static __init int ite_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
1175 {
1176 	switch (device) {
1177 	case PCI_DEVICE_ID_ITE_IT8330G_0:
1178 		r->name = "ITE";
1179 		r->get = pirq_ite_get;
1180 		r->set = pirq_ite_set;
1181 		return 1;
1182 	}
1183 	return 0;
1184 }
1185 
1186 static __init int ali_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
1187 {
1188 	switch (device) {
1189 	case PCI_DEVICE_ID_AL_M1489:
1190 		r->name = "FinALi";
1191 		r->get = pirq_finali_get;
1192 		r->set = pirq_finali_set;
1193 		r->lvl = pirq_finali_lvl;
1194 		return 1;
1195 	case PCI_DEVICE_ID_AL_M1533:
1196 	case PCI_DEVICE_ID_AL_M1563:
1197 		r->name = "ALI";
1198 		r->get = pirq_ali_get;
1199 		r->set = pirq_ali_set;
1200 		return 1;
1201 	}
1202 	return 0;
1203 }
1204 
1205 static __init int amd_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
1206 {
1207 	switch (device) {
1208 	case PCI_DEVICE_ID_AMD_VIPER_740B:
1209 		r->name = "AMD756";
1210 		break;
1211 	case PCI_DEVICE_ID_AMD_VIPER_7413:
1212 		r->name = "AMD766";
1213 		break;
1214 	case PCI_DEVICE_ID_AMD_VIPER_7443:
1215 		r->name = "AMD768";
1216 		break;
1217 	default:
1218 		return 0;
1219 	}
1220 	r->get = pirq_amd756_get;
1221 	r->set = pirq_amd756_set;
1222 	return 1;
1223 }
1224 
1225 static __init int pico_router_probe(struct irq_router *r, struct pci_dev *router, u16 device)
1226 {
1227 	switch (device) {
1228 	case PCI_DEVICE_ID_PICOPOWER_PT86C523:
1229 		r->name = "PicoPower PT86C523";
1230 		r->get = pirq_pico_get;
1231 		r->set = pirq_pico_set;
1232 		return 1;
1233 
1234 	case PCI_DEVICE_ID_PICOPOWER_PT86C523BBP:
1235 		r->name = "PicoPower PT86C523 rev. BB+";
1236 		r->get = pirq_pico_get;
1237 		r->set = pirq_pico_set;
1238 		return 1;
1239 	}
1240 	return 0;
1241 }
1242 
1243 static __initdata struct irq_router_handler pirq_routers[] = {
1244 	{ PCI_VENDOR_ID_INTEL, intel_router_probe },
1245 	{ PCI_VENDOR_ID_AL, ali_router_probe },
1246 	{ PCI_VENDOR_ID_ITE, ite_router_probe },
1247 	{ PCI_VENDOR_ID_VIA, via_router_probe },
1248 	{ PCI_VENDOR_ID_OPTI, opti_router_probe },
1249 	{ PCI_VENDOR_ID_SI, sis_router_probe },
1250 	{ PCI_VENDOR_ID_CYRIX, cyrix_router_probe },
1251 	{ PCI_VENDOR_ID_VLSI, vlsi_router_probe },
1252 	{ PCI_VENDOR_ID_SERVERWORKS, serverworks_router_probe },
1253 	{ PCI_VENDOR_ID_AMD, amd_router_probe },
1254 	{ PCI_VENDOR_ID_PICOPOWER, pico_router_probe },
1255 	/* Someone with docs needs to add the ATI Radeon IGP */
1256 	{ 0, NULL }
1257 };
1258 static struct irq_router pirq_router;
1259 static struct pci_dev *pirq_router_dev;
1260 
1261 
1262 /*
1263  *	FIXME: should we have an option to say "generic for
1264  *	chipset" ?
1265  */
1266 
1267 static bool __init pirq_try_router(struct irq_router *r,
1268 				   struct irq_routing_table *rt,
1269 				   struct pci_dev *dev)
1270 {
1271 	struct irq_router_handler *h;
1272 
1273 	DBG(KERN_DEBUG "PCI: Trying IRQ router for [%04x:%04x]\n",
1274 	    dev->vendor, dev->device);
1275 
1276 	for (h = pirq_routers; h->vendor; h++) {
1277 		/* First look for a router match */
1278 		if (rt->rtr_vendor == h->vendor &&
1279 		    h->probe(r, dev, rt->rtr_device))
1280 			return true;
1281 		/* Fall back to a device match */
1282 		if (dev->vendor == h->vendor &&
1283 		    h->probe(r, dev, dev->device))
1284 			return true;
1285 	}
1286 	return false;
1287 }
1288 
1289 static void __init pirq_find_router(struct irq_router *r)
1290 {
1291 	struct irq_routing_table *rt = pirq_table;
1292 	struct pci_dev *dev;
1293 
1294 #ifdef CONFIG_PCI_BIOS
1295 	if (!rt->signature) {
1296 		printk(KERN_INFO "PCI: Using BIOS for IRQ routing\n");
1297 		r->set = pirq_bios_set;
1298 		r->name = "BIOS";
1299 		return;
1300 	}
1301 #endif
1302 
1303 	/* Default unless a driver reloads it */
1304 	r->name = "default";
1305 	r->get = NULL;
1306 	r->set = NULL;
1307 
1308 	DBG(KERN_DEBUG "PCI: Attempting to find IRQ router for [%04x:%04x]\n",
1309 	    rt->rtr_vendor, rt->rtr_device);
1310 
1311 	/* Use any vendor:device provided by the routing table or try all.  */
1312 	if (rt->rtr_vendor) {
1313 		dev = pci_get_domain_bus_and_slot(0, rt->rtr_bus,
1314 						  rt->rtr_devfn);
1315 		if (dev && pirq_try_router(r, rt, dev))
1316 			pirq_router_dev = dev;
1317 	} else {
1318 		dev = NULL;
1319 		for_each_pci_dev(dev) {
1320 			if (pirq_try_router(r, rt, dev)) {
1321 				pirq_router_dev = dev;
1322 				break;
1323 			}
1324 		}
1325 	}
1326 
1327 	if (pirq_router_dev)
1328 		dev_info(&pirq_router_dev->dev, "%s IRQ router [%04x:%04x]\n",
1329 			 pirq_router.name,
1330 			 pirq_router_dev->vendor, pirq_router_dev->device);
1331 	else
1332 		DBG(KERN_DEBUG "PCI: Interrupt router not found at "
1333 		    "%02x:%02x\n", rt->rtr_bus, rt->rtr_devfn);
1334 
1335 	/* The device remains referenced for the kernel lifetime */
1336 }
1337 
1338 /*
1339  * We're supposed to match on the PCI device only and not the function,
1340  * but some BIOSes build their tables with the PCI function included
1341  * for motherboard devices, so if a complete match is found, then give
1342  * it precedence over a slot match.
1343  */
1344 static struct irq_info *pirq_get_dev_info(struct pci_dev *dev)
1345 {
1346 	struct irq_routing_table *rt = pirq_table;
1347 	int entries = (rt->size - sizeof(struct irq_routing_table)) /
1348 		sizeof(struct irq_info);
1349 	struct irq_info *slotinfo = NULL;
1350 	struct irq_info *info;
1351 
1352 	for (info = rt->slots; entries--; info++)
1353 		if (info->bus == dev->bus->number) {
1354 			if (info->devfn == dev->devfn)
1355 				return info;
1356 			if (!slotinfo &&
1357 			    PCI_SLOT(info->devfn) == PCI_SLOT(dev->devfn))
1358 				slotinfo = info;
1359 		}
1360 	return slotinfo;
1361 }
1362 
1363 /*
1364  * Buses behind bridges are typically not listed in the PIRQ routing table.
1365  * Do the usual dance then and walk the tree of bridges up adjusting the
1366  * pin number accordingly on the way until the originating root bus device
1367  * has been reached and then use its routing information.
1368  */
1369 static struct irq_info *pirq_get_info(struct pci_dev *dev, u8 *pin)
1370 {
1371 	struct pci_dev *temp_dev = dev;
1372 	struct irq_info *info;
1373 	u8 temp_pin = *pin;
1374 	u8 dpin = temp_pin;
1375 
1376 	info = pirq_get_dev_info(dev);
1377 	while (!info && temp_dev->bus->parent) {
1378 		struct pci_dev *bridge = temp_dev->bus->self;
1379 
1380 		temp_pin = pci_swizzle_interrupt_pin(temp_dev, temp_pin);
1381 		info = pirq_get_dev_info(bridge);
1382 		if (info)
1383 			dev_warn(&dev->dev,
1384 				 "using bridge %s INT %c to get INT %c\n",
1385 				 pci_name(bridge),
1386 				 'A' + temp_pin - 1, 'A' + dpin - 1);
1387 
1388 		temp_dev = bridge;
1389 	}
1390 	*pin = temp_pin;
1391 	return info;
1392 }
1393 
1394 static int pcibios_lookup_irq(struct pci_dev *dev, int assign)
1395 {
1396 	struct irq_info *info;
1397 	int i, pirq, newirq;
1398 	u8 dpin, pin;
1399 	int irq = 0;
1400 	u32 mask;
1401 	struct irq_router *r = &pirq_router;
1402 	struct pci_dev *dev2 = NULL;
1403 	char *msg = NULL;
1404 
1405 	/* Find IRQ pin */
1406 	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &dpin);
1407 	if (!dpin) {
1408 		dev_dbg(&dev->dev, "no interrupt pin\n");
1409 		return 0;
1410 	}
1411 
1412 	if (io_apic_assign_pci_irqs)
1413 		return 0;
1414 
1415 	/* Find IRQ routing entry */
1416 
1417 	if (!pirq_table)
1418 		return 0;
1419 
1420 	pin = dpin;
1421 	info = pirq_get_info(dev, &pin);
1422 	if (!info) {
1423 		dev_dbg(&dev->dev, "PCI INT %c not found in routing table\n",
1424 			'A' + dpin - 1);
1425 		return 0;
1426 	}
1427 	pirq = info->irq[pin - 1].link;
1428 	mask = info->irq[pin - 1].bitmap;
1429 	if (!pirq) {
1430 		dev_dbg(&dev->dev, "PCI INT %c not routed\n", 'A' + dpin - 1);
1431 		return 0;
1432 	}
1433 	dev_dbg(&dev->dev, "PCI INT %c -> PIRQ %02x, mask %04x, excl %04x",
1434 		'A' + dpin - 1, pirq, mask, pirq_table->exclusive_irqs);
1435 	mask &= pcibios_irq_mask;
1436 
1437 	/* Work around broken HP Pavilion Notebooks which assign USB to
1438 	   IRQ 9 even though it is actually wired to IRQ 11 */
1439 
1440 	if (broken_hp_bios_irq9 && pirq == 0x59 && dev->irq == 9) {
1441 		dev->irq = 11;
1442 		pci_write_config_byte(dev, PCI_INTERRUPT_LINE, 11);
1443 		r->set(pirq_router_dev, dev, pirq, 11);
1444 	}
1445 
1446 	/* same for Acer Travelmate 360, but with CB and irq 11 -> 10 */
1447 	if (acer_tm360_irqrouting && dev->irq == 11 &&
1448 		dev->vendor == PCI_VENDOR_ID_O2) {
1449 		pirq = 0x68;
1450 		mask = 0x400;
1451 		dev->irq = r->get(pirq_router_dev, dev, pirq);
1452 		pci_write_config_byte(dev, PCI_INTERRUPT_LINE, dev->irq);
1453 	}
1454 
1455 	/*
1456 	 * Find the best IRQ to assign: use the one
1457 	 * reported by the device if possible.
1458 	 */
1459 	newirq = dev->irq;
1460 	if (newirq && !((1 << newirq) & mask)) {
1461 		if (pci_probe & PCI_USE_PIRQ_MASK)
1462 			newirq = 0;
1463 		else
1464 			dev_warn(&dev->dev, "IRQ %d doesn't match PIRQ mask "
1465 				 "%#x; try pci=usepirqmask\n", newirq, mask);
1466 	}
1467 	if (!newirq && assign) {
1468 		for (i = 0; i < 16; i++) {
1469 			if (!(mask & (1 << i)))
1470 				continue;
1471 			if (pirq_penalty[i] < pirq_penalty[newirq] &&
1472 				can_request_irq(i, IRQF_SHARED))
1473 				newirq = i;
1474 		}
1475 	}
1476 	dev_dbg(&dev->dev, "PCI INT %c -> newirq %d", 'A' + dpin - 1, newirq);
1477 
1478 	/* Check if it is hardcoded */
1479 	if ((pirq & 0xf0) == 0xf0) {
1480 		irq = pirq & 0xf;
1481 		msg = "hardcoded";
1482 	} else if (r->get && (irq = r->get(pirq_router_dev, dev, pirq)) && \
1483 	((!(pci_probe & PCI_USE_PIRQ_MASK)) || ((1 << irq) & mask))) {
1484 		msg = "found";
1485 		if (r->lvl)
1486 			r->lvl(pirq_router_dev, dev, pirq, irq);
1487 		else
1488 			elcr_set_level_irq(irq);
1489 	} else if (newirq && r->set &&
1490 		(dev->class >> 8) != PCI_CLASS_DISPLAY_VGA) {
1491 		if (r->set(pirq_router_dev, dev, pirq, newirq)) {
1492 			if (r->lvl)
1493 				r->lvl(pirq_router_dev, dev, pirq, newirq);
1494 			else
1495 				elcr_set_level_irq(newirq);
1496 			msg = "assigned";
1497 			irq = newirq;
1498 		}
1499 	}
1500 
1501 	if (!irq) {
1502 		if (newirq && mask == (1 << newirq)) {
1503 			msg = "guessed";
1504 			irq = newirq;
1505 		} else {
1506 			dev_dbg(&dev->dev, "can't route interrupt\n");
1507 			return 0;
1508 		}
1509 	}
1510 	dev_info(&dev->dev, "%s PCI INT %c -> IRQ %d\n",
1511 		 msg, 'A' + dpin - 1, irq);
1512 
1513 	/* Update IRQ for all devices with the same pirq value */
1514 	for_each_pci_dev(dev2) {
1515 		pci_read_config_byte(dev2, PCI_INTERRUPT_PIN, &dpin);
1516 		if (!dpin)
1517 			continue;
1518 
1519 		pin = dpin;
1520 		info = pirq_get_info(dev2, &pin);
1521 		if (!info)
1522 			continue;
1523 		if (info->irq[pin - 1].link == pirq) {
1524 			/*
1525 			 * We refuse to override the dev->irq
1526 			 * information. Give a warning!
1527 			 */
1528 			if (dev2->irq && dev2->irq != irq && \
1529 			(!(pci_probe & PCI_USE_PIRQ_MASK) || \
1530 			((1 << dev2->irq) & mask))) {
1531 #ifndef CONFIG_PCI_MSI
1532 				dev_info(&dev2->dev, "IRQ routing conflict: "
1533 					 "have IRQ %d, want IRQ %d\n",
1534 					 dev2->irq, irq);
1535 #endif
1536 				continue;
1537 			}
1538 			dev2->irq = irq;
1539 			pirq_penalty[irq]++;
1540 			if (dev != dev2)
1541 				dev_info(&dev->dev, "sharing IRQ %d with %s\n",
1542 					 irq, pci_name(dev2));
1543 		}
1544 	}
1545 	return 1;
1546 }
1547 
1548 void __init pcibios_fixup_irqs(void)
1549 {
1550 	struct pci_dev *dev = NULL;
1551 	u8 pin;
1552 
1553 	DBG(KERN_DEBUG "PCI: IRQ fixup\n");
1554 	for_each_pci_dev(dev) {
1555 		/*
1556 		 * If the BIOS has set an out of range IRQ number, just
1557 		 * ignore it.  Also keep track of which IRQ's are
1558 		 * already in use.
1559 		 */
1560 		if (dev->irq >= 16) {
1561 			dev_dbg(&dev->dev, "ignoring bogus IRQ %d\n", dev->irq);
1562 			dev->irq = 0;
1563 		}
1564 		/*
1565 		 * If the IRQ is already assigned to a PCI device,
1566 		 * ignore its ISA use penalty
1567 		 */
1568 		if (pirq_penalty[dev->irq] >= 100 &&
1569 				pirq_penalty[dev->irq] < 100000)
1570 			pirq_penalty[dev->irq] = 0;
1571 		pirq_penalty[dev->irq]++;
1572 	}
1573 
1574 	if (io_apic_assign_pci_irqs)
1575 		return;
1576 
1577 	dev = NULL;
1578 	for_each_pci_dev(dev) {
1579 		pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
1580 		if (!pin)
1581 			continue;
1582 
1583 		/*
1584 		 * Still no IRQ? Try to lookup one...
1585 		 */
1586 		if (!dev->irq)
1587 			pcibios_lookup_irq(dev, 0);
1588 	}
1589 }
1590 
1591 /*
1592  * Work around broken HP Pavilion Notebooks which assign USB to
1593  * IRQ 9 even though it is actually wired to IRQ 11
1594  */
1595 static int __init fix_broken_hp_bios_irq9(const struct dmi_system_id *d)
1596 {
1597 	if (!broken_hp_bios_irq9) {
1598 		broken_hp_bios_irq9 = 1;
1599 		printk(KERN_INFO "%s detected - fixing broken IRQ routing\n",
1600 			d->ident);
1601 	}
1602 	return 0;
1603 }
1604 
1605 /*
1606  * Work around broken Acer TravelMate 360 Notebooks which assign
1607  * Cardbus to IRQ 11 even though it is actually wired to IRQ 10
1608  */
1609 static int __init fix_acer_tm360_irqrouting(const struct dmi_system_id *d)
1610 {
1611 	if (!acer_tm360_irqrouting) {
1612 		acer_tm360_irqrouting = 1;
1613 		printk(KERN_INFO "%s detected - fixing broken IRQ routing\n",
1614 			d->ident);
1615 	}
1616 	return 0;
1617 }
1618 
1619 static const struct dmi_system_id pciirq_dmi_table[] __initconst = {
1620 	{
1621 		.callback = fix_broken_hp_bios_irq9,
1622 		.ident = "HP Pavilion N5400 Series Laptop",
1623 		.matches = {
1624 			DMI_MATCH(DMI_SYS_VENDOR, "Hewlett-Packard"),
1625 			DMI_MATCH(DMI_BIOS_VERSION, "GE.M1.03"),
1626 			DMI_MATCH(DMI_PRODUCT_VERSION,
1627 				"HP Pavilion Notebook Model GE"),
1628 			DMI_MATCH(DMI_BOARD_VERSION, "OmniBook N32N-736"),
1629 		},
1630 	},
1631 	{
1632 		.callback = fix_acer_tm360_irqrouting,
1633 		.ident = "Acer TravelMate 36x Laptop",
1634 		.matches = {
1635 			DMI_MATCH(DMI_SYS_VENDOR, "Acer"),
1636 			DMI_MATCH(DMI_PRODUCT_NAME, "TravelMate 360"),
1637 		},
1638 	},
1639 	{ }
1640 };
1641 
1642 void __init pcibios_irq_init(void)
1643 {
1644 	struct irq_routing_table *rtable = NULL;
1645 
1646 	DBG(KERN_DEBUG "PCI: IRQ init\n");
1647 
1648 	if (raw_pci_ops == NULL)
1649 		return;
1650 
1651 	dmi_check_system(pciirq_dmi_table);
1652 
1653 	pirq_table = pirq_find_routing_table();
1654 
1655 #ifdef CONFIG_PCI_BIOS
1656 	if (!pirq_table && (pci_probe & PCI_BIOS_IRQ_SCAN)) {
1657 		pirq_table = pcibios_get_irq_routing_table();
1658 		rtable = pirq_table;
1659 	}
1660 #endif
1661 	if (pirq_table) {
1662 		pirq_peer_trick();
1663 		pirq_find_router(&pirq_router);
1664 		if (pirq_table->exclusive_irqs) {
1665 			int i;
1666 			for (i = 0; i < 16; i++)
1667 				if (!(pirq_table->exclusive_irqs & (1 << i)))
1668 					pirq_penalty[i] += 100;
1669 		}
1670 		/*
1671 		 * If we're using the I/O APIC, avoid using the PCI IRQ
1672 		 * routing table
1673 		 */
1674 		if (io_apic_assign_pci_irqs) {
1675 			kfree(rtable);
1676 			pirq_table = NULL;
1677 		}
1678 	}
1679 
1680 	x86_init.pci.fixup_irqs();
1681 
1682 	if (io_apic_assign_pci_irqs && pci_routeirq) {
1683 		struct pci_dev *dev = NULL;
1684 		/*
1685 		 * PCI IRQ routing is set up by pci_enable_device(), but we
1686 		 * also do it here in case there are still broken drivers that
1687 		 * don't use pci_enable_device().
1688 		 */
1689 		printk(KERN_INFO "PCI: Routing PCI interrupts for all devices because \"pci=routeirq\" specified\n");
1690 		for_each_pci_dev(dev)
1691 			pirq_enable_irq(dev);
1692 	}
1693 }
1694 
1695 static void pirq_penalize_isa_irq(int irq, int active)
1696 {
1697 	/*
1698 	 *  If any ISAPnP device reports an IRQ in its list of possible
1699 	 *  IRQ's, we try to avoid assigning it to PCI devices.
1700 	 */
1701 	if (irq < 16) {
1702 		if (active)
1703 			pirq_penalty[irq] += 1000;
1704 		else
1705 			pirq_penalty[irq] += 100;
1706 	}
1707 }
1708 
1709 void pcibios_penalize_isa_irq(int irq, int active)
1710 {
1711 #ifdef CONFIG_ACPI
1712 	if (!acpi_noirq)
1713 		acpi_penalize_isa_irq(irq, active);
1714 	else
1715 #endif
1716 		pirq_penalize_isa_irq(irq, active);
1717 }
1718 
1719 static int pirq_enable_irq(struct pci_dev *dev)
1720 {
1721 	u8 pin = 0;
1722 
1723 	pci_read_config_byte(dev, PCI_INTERRUPT_PIN, &pin);
1724 	if (pin && !pcibios_lookup_irq(dev, 1)) {
1725 		char *msg = "";
1726 
1727 		if (!io_apic_assign_pci_irqs && dev->irq)
1728 			return 0;
1729 
1730 		if (io_apic_assign_pci_irqs) {
1731 #ifdef CONFIG_X86_IO_APIC
1732 			struct pci_dev *temp_dev;
1733 			int irq;
1734 
1735 			if (dev->irq_managed && dev->irq > 0)
1736 				return 0;
1737 
1738 			irq = IO_APIC_get_PCI_irq_vector(dev->bus->number,
1739 						PCI_SLOT(dev->devfn), pin - 1);
1740 			/*
1741 			 * Busses behind bridges are typically not listed in the MP-table.
1742 			 * In this case we have to look up the IRQ based on the parent bus,
1743 			 * parent slot, and pin number. The SMP code detects such bridged
1744 			 * busses itself so we should get into this branch reliably.
1745 			 */
1746 			temp_dev = dev;
1747 			while (irq < 0 && dev->bus->parent) { /* go back to the bridge */
1748 				struct pci_dev *bridge = dev->bus->self;
1749 
1750 				pin = pci_swizzle_interrupt_pin(dev, pin);
1751 				irq = IO_APIC_get_PCI_irq_vector(bridge->bus->number,
1752 						PCI_SLOT(bridge->devfn),
1753 						pin - 1);
1754 				if (irq >= 0)
1755 					dev_warn(&dev->dev, "using bridge %s "
1756 						 "INT %c to get IRQ %d\n",
1757 						 pci_name(bridge), 'A' + pin - 1,
1758 						 irq);
1759 				dev = bridge;
1760 			}
1761 			dev = temp_dev;
1762 			if (irq >= 0) {
1763 				dev->irq_managed = 1;
1764 				dev->irq = irq;
1765 				dev_info(&dev->dev, "PCI->APIC IRQ transform: "
1766 					 "INT %c -> IRQ %d\n", 'A' + pin - 1, irq);
1767 				return 0;
1768 			} else
1769 				msg = "; probably buggy MP table";
1770 #endif
1771 		} else if (pci_probe & PCI_BIOS_IRQ_SCAN)
1772 			msg = "";
1773 		else
1774 			msg = "; please try using pci=biosirq";
1775 
1776 		/*
1777 		 * With IDE legacy devices the IRQ lookup failure is not
1778 		 * a problem..
1779 		 */
1780 		if (dev->class >> 8 == PCI_CLASS_STORAGE_IDE &&
1781 				!(dev->class & 0x5))
1782 			return 0;
1783 
1784 		dev_warn(&dev->dev, "can't find IRQ for PCI INT %c%s\n",
1785 			 'A' + pin - 1, msg);
1786 	}
1787 	return 0;
1788 }
1789 
1790 bool mp_should_keep_irq(struct device *dev)
1791 {
1792 	if (dev->power.is_prepared)
1793 		return true;
1794 #ifdef CONFIG_PM
1795 	if (dev->power.runtime_status == RPM_SUSPENDING)
1796 		return true;
1797 #endif
1798 
1799 	return false;
1800 }
1801 
1802 static void pirq_disable_irq(struct pci_dev *dev)
1803 {
1804 	if (io_apic_assign_pci_irqs && !mp_should_keep_irq(&dev->dev) &&
1805 	    dev->irq_managed && dev->irq) {
1806 		mp_unmap_irq(dev->irq);
1807 		dev->irq = 0;
1808 		dev->irq_managed = 0;
1809 	}
1810 }
1811