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pci_intr_fixup.c revision 1.6
      1 /*	$NetBSD: pci_intr_fixup.c,v 1.6 2000/07/09 00:42:47 mycroft Exp $	*/
      2 
      3 /*-
      4  * Copyright (c) 1999 The NetBSD Foundation, Inc.
      5  * All rights reserved.
      6  *
      7  * This code is derived from software contributed to The NetBSD Foundation
      8  * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
      9  * NASA Ames Research Center.
     10  *
     11  * Redistribution and use in source and binary forms, with or without
     12  * modification, are permitted provided that the following conditions
     13  * are met:
     14  * 1. Redistributions of source code must retain the above copyright
     15  *    notice, this list of conditions and the following disclaimer.
     16  * 2. Redistributions in binary form must reproduce the above copyright
     17  *    notice, this list of conditions and the following disclaimer in the
     18  *    documentation and/or other materials provided with the distribution.
     19  * 3. All advertising materials mentioning features or use of this software
     20  *    must display the following acknowledgement:
     21  *	This product includes software developed by the NetBSD
     22  *	Foundation, Inc. and its contributors.
     23  * 4. Neither the name of The NetBSD Foundation nor the names of its
     24  *    contributors may be used to endorse or promote products derived
     25  *    from this software without specific prior written permission.
     26  *
     27  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
     28  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
     29  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
     30  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
     31  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
     32  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
     33  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
     34  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
     35  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
     36  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
     37  * POSSIBILITY OF SUCH DAMAGE.
     38  */
     39 
     40 /*
     41  * Copyright (c) 1999, by UCHIYAMA Yasushi
     42  * All rights reserved.
     43  *
     44  * Redistribution and use in source and binary forms, with or without
     45  * modification, are permitted provided that the following conditions
     46  * are met:
     47  * 1. Redistributions of source code must retain the above copyright
     48  *    notice, this list of conditions and the following disclaimer.
     49  * 2. The name of the developer may NOT be used to endorse or promote products
     50  *    derived from this software without specific prior written permission.
     51  *
     52  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
     53  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     54  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     55  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
     56  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     57  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     58  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     59  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     60  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     61  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     62  * SUCH DAMAGE.
     63  */
     64 
     65 /*
     66  * PCI Interrupt Router support.
     67  */
     68 
     69 #include "opt_pcibios.h"
     70 
     71 #include <sys/param.h>
     72 #include <sys/systm.h>
     73 #include <sys/kernel.h>
     74 #include <sys/malloc.h>
     75 #include <sys/queue.h>
     76 #include <sys/device.h>
     77 
     78 #include <machine/bus.h>
     79 #include <machine/intr.h>
     80 
     81 #include <dev/pci/pcireg.h>
     82 #include <dev/pci/pcivar.h>
     83 #include <dev/pci/pcidevs.h>
     84 
     85 #include <i386/isa/icu.h>
     86 #include <i386/pci/pci_intr_fixup.h>
     87 #include <i386/pci/pcibios.h>
     88 
     89 struct pciintr_link_map {
     90 	int link;
     91 	int clink;
     92 	int irq;
     93 	u_int16_t bitmap;
     94 	int fixup_stage;
     95 	int old_irq;
     96 	SIMPLEQ_ENTRY(pciintr_link_map) list;
     97 };
     98 
     99 pciintr_icu_tag_t pciintr_icu_tag;
    100 pciintr_icu_handle_t pciintr_icu_handle;
    101 
    102 struct pciintr_link_map *pciintr_link_lookup_pin
    103 	__P((struct pcibios_intr_routing *, int));
    104 struct pciintr_link_map *pciintr_link_lookup_link __P((int));
    105 struct pciintr_link_map *pciintr_link_alloc __P((struct pcibios_intr_routing *,
    106 	int));
    107 struct pcibios_intr_routing *pciintr_pir_lookup __P((int, int));
    108 int	pciintr_link_init __P((void));
    109 int	pciintr_link_fixup __P((void));
    110 int	pciintr_link_route __P((u_int16_t *));
    111 int	pciintr_irq_release __P((u_int16_t *));
    112 int	pciintr_header_fixup __P((pci_chipset_tag_t));
    113 void	pciintr_do_header_fixup __P((pci_chipset_tag_t, pcitag_t));
    114 
    115 SIMPLEQ_HEAD(, pciintr_link_map) pciintr_link_map_list;
    116 
    117 const struct pciintr_icu_table {
    118 	pci_vendor_id_t	piit_vendor;
    119 	pci_product_id_t piit_product;
    120 	int (*piit_init) __P((pci_chipset_tag_t,
    121 		bus_space_tag_t, pcitag_t, pciintr_icu_tag_t *,
    122 		pciintr_icu_handle_t *));
    123 } pciintr_icu_table[] = {
    124 	{ PCI_VENDOR_INTEL,	PCI_PRODUCT_INTEL_82371MX,
    125 	  piix_init },
    126 	{ PCI_VENDOR_INTEL,	PCI_PRODUCT_INTEL_82371AB_ISA,
    127 	  piix_init },
    128 	{ PCI_VENDOR_INTEL,	PCI_PRODUCT_INTEL_82371FB_ISA,
    129 	  piix_init },
    130 	{ PCI_VENDOR_INTEL,	PCI_PRODUCT_INTEL_82371SB_ISA,
    131 	  piix_init },
    132 
    133 	{ PCI_VENDOR_OPTI,	PCI_PRODUCT_OPTI_82C558,
    134 	  opti82c558_init },
    135 	{ PCI_VENDOR_OPTI,	PCI_PRODUCT_OPTI_82C700,
    136 	  opti82c700_init },
    137 
    138 	{ PCI_VENDOR_VIATECH,	PCI_PRODUCT_VIATECH_VT82C586_ISA,
    139 	  via82c586_init, },
    140 
    141 	{ PCI_VENDOR_SIS,	PCI_PRODUCT_SIS_85C503,
    142 	  sis85c503_init },
    143 
    144 	{ 0,			0,
    145 	  NULL },
    146 };
    147 
    148 const struct pciintr_icu_table *pciintr_icu_lookup __P((pcireg_t));
    149 
    150 const struct pciintr_icu_table *
    151 pciintr_icu_lookup(id)
    152 	pcireg_t id;
    153 {
    154 	const struct pciintr_icu_table *piit;
    155 
    156 	for (piit = pciintr_icu_table;
    157 	     piit->piit_init != NULL;
    158 	     piit++) {
    159 		if (PCI_VENDOR(id) == piit->piit_vendor &&
    160 		    PCI_PRODUCT(id) == piit->piit_product)
    161 			return (piit);
    162 	}
    163 
    164 	return (NULL);
    165 }
    166 
    167 struct pciintr_link_map *
    168 pciintr_link_lookup_pin(pir, pin)
    169 	struct pcibios_intr_routing *pir;
    170 	int pin;
    171 {
    172 
    173 	return (pciintr_link_lookup_link(pir->linkmap[pin].link));
    174 }
    175 
    176 struct pciintr_link_map *
    177 pciintr_link_lookup_link(link)
    178 	int link;
    179 {
    180 	struct pciintr_link_map *l;
    181 
    182 	for (l = SIMPLEQ_FIRST(&pciintr_link_map_list); l != NULL;
    183 	     l = SIMPLEQ_NEXT(l, list)) {
    184 		if (l->link == link)
    185 			return (l);
    186 	}
    187 
    188 	return (NULL);
    189 }
    190 
    191 struct pciintr_link_map *
    192 pciintr_link_alloc(pir, pin)
    193 	struct pcibios_intr_routing *pir;
    194 	int pin;
    195 {
    196 	struct pciintr_link_map *l, *lstart;
    197 
    198 	l = malloc(sizeof(*l), M_DEVBUF, M_NOWAIT);
    199 	if (l == NULL)
    200 		panic("pciintr_link_alloc");
    201 
    202 	memset(l, 0, sizeof(*l));
    203 
    204 	l->link = pir->linkmap[pin].link;
    205 	l->bitmap = pir->linkmap[pin].bitmap;
    206 
    207 	lstart = SIMPLEQ_FIRST(&pciintr_link_map_list);
    208 	if (lstart == NULL || lstart->link < l->link)
    209 		SIMPLEQ_INSERT_TAIL(&pciintr_link_map_list, l, list);
    210 	else
    211 		SIMPLEQ_INSERT_HEAD(&pciintr_link_map_list, l, list);
    212 
    213 	return (l);
    214 }
    215 
    216 struct pcibios_intr_routing *
    217 pciintr_pir_lookup(bus, device)
    218 	int bus, device;
    219 {
    220 	struct pcibios_intr_routing *pir;
    221 	int entry;
    222 
    223 	if (pcibios_pir_table == NULL)
    224 		return (NULL);
    225 
    226 	for (entry = 0; entry < pcibios_pir_table_nentries; entry++) {
    227 		pir = &pcibios_pir_table[entry];
    228 		if (pir->bus == bus && ((pir->device >> 3) & 0x1f) == device)
    229 			return (pir);
    230 	}
    231 
    232 	return (NULL);
    233 }
    234 
    235 int
    236 pciintr_link_init()
    237 {
    238 	int entry, pin, error, link, clink;
    239 	struct pcibios_intr_routing *pir;
    240 	struct pciintr_link_map *l;
    241 
    242 	if (pcibios_pir_table == NULL) {
    243 		/* No PIR table; can't do anything. */
    244 		printf("pciintr_link_init: no PIR table\n");
    245 		return (1);
    246 	}
    247 
    248 	error = 0;
    249 	SIMPLEQ_INIT(&pciintr_link_map_list);
    250 
    251 	for (entry = 0; entry < pcibios_pir_table_nentries; entry++) {
    252 		pir = &pcibios_pir_table[entry];
    253 		for (pin = 0; pin < 4; pin++) {
    254 			link = pir->linkmap[pin].link;
    255 			if (link == 0) {
    256 				/* No connection for this pin. */
    257 				continue;
    258 			}
    259 
    260 			/*
    261 			 * Check the link value by asking the ICU for
    262 			 * the canonical link value.
    263 			 */
    264 			if (pciintr_icu_getclink(pciintr_icu_tag,
    265 			    pciintr_icu_handle, link, &clink) != 0) {
    266 				/*
    267 				 * Table entry is bogus.  Just ignore it.
    268 				 */
    269 #ifdef PCIINTR_DEBUG
    270 				printf("pciintr_link_init: bad table entry: "
    271 				    "bus %d device %d link 0x%02x\n",
    272 				    pir->bus, (pir->device >> 3 & 0x1f), link);
    273 #endif
    274 				continue;
    275 			}
    276 
    277 			/*
    278 			 * Multiple devices may be wired to the same
    279 			 * interrupt; check to see if we've seen this
    280 			 * one already.  If not, allocate a new link
    281 			 * map entry and stuff it in the map.
    282 			 */
    283 			l = pciintr_link_lookup_pin(pir, pin);
    284 			if (l == NULL)
    285 				(void) pciintr_link_alloc(pir, pin);
    286 		}
    287 	}
    288 
    289 	return (error);
    290 }
    291 
    292 int
    293 pciintr_link_fixup()
    294 {
    295 	struct pciintr_link_map *l;
    296 	u_int16_t pciirq, bitmap;
    297 	int i, j, cnt, irq;
    298 
    299 	/*
    300 	 * First stage: Attempt to connect PIRQs which aren't
    301 	 * yet connected.
    302 	 */
    303 	pciirq = 0;
    304 
    305 	for (l = SIMPLEQ_FIRST(&pciintr_link_map_list); l != NULL;
    306 	     l = SIMPLEQ_NEXT(l, list)) {
    307 		/*
    308 		 * Get the canonical link value for this entry.
    309 		 */
    310 		if (pciintr_icu_getclink(pciintr_icu_tag, pciintr_icu_handle,
    311 		    l->link, &l->clink) != 0) {
    312 			/*
    313 			 * ICU doesn't understand this link value.
    314 			 */
    315 #ifdef PCIINTR_DEBUG
    316 			printf("pciintr_link_fixup: link 0x%02x invalid\n",
    317 			    l->link);
    318 #endif
    319 			l->clink = -1;
    320 			continue;
    321 		}
    322 
    323 		/*
    324 		 * Determine if this PIRQ is mapped to an IRQ.
    325 		 */
    326 		if (pciintr_icu_get_intr(pciintr_icu_tag, pciintr_icu_handle,
    327 		    l->clink, &irq) != 0) {
    328 			/*
    329 			 * ICU doesn't understand this PIRQ value.
    330 			 */
    331 			l->clink = -1;
    332 #ifdef PCIINTR_DEBUG
    333 			printf("pciintr_link_fixup: PIRQ %d invalid\n",
    334 			    l->clink);
    335 #endif
    336 			continue;
    337 		}
    338 
    339 		if (irq == 0xff) {
    340 			/*
    341 			 * Interrupt isn't connected.  Attempt to assign
    342 			 * it to an IRQ.
    343 			 */
    344 #ifdef PCIINTR_DEBUG
    345 			printf("pciintr_link_fixup: PIRQ %d not connected",
    346 			    l->clink);
    347 #endif
    348 			bitmap = l->bitmap;
    349 			for (i = 0, j = 0xff, cnt = 0; i < 16; i++)
    350 				if (bitmap & (1 << i))
    351 					j = i, cnt++;
    352 			/*
    353 			 * Just do the easy case now; we'll defer the
    354 			 * harder ones to Stage 2.
    355 			 */
    356 			if (cnt == 1) {
    357 				l->irq = j;
    358 				l->old_irq = irq;
    359 				l->fixup_stage = 1;
    360 				pciirq |= 1 << j;
    361 #ifdef PCIINTR_DEBUG
    362 				printf(", assigning IRQ %d", l->irq);
    363 #endif
    364 			}
    365 #ifdef PCIINTR_DEBUG
    366 			printf("\n");
    367 #endif
    368 		} else {
    369 			/*
    370 			 * Interrupt is already connected.  Don't do
    371 			 * anything to it.
    372 			 */
    373 			l->irq = irq;
    374 			pciirq |= 1 << irq;
    375 #ifdef PCIINTR_DEBUG
    376 			printf("pciintr_link_fixup: PIRQ %d already connected "
    377 			    "to IRQ %d\n", l->clink, l->irq);
    378 #endif
    379 		}
    380 	}
    381 
    382 	/*
    383 	 * Stage 2: Attempt to connect PIRQs which we didn't
    384 	 * connect in Stage 1.
    385 	 */
    386 	for (l = SIMPLEQ_FIRST(&pciintr_link_map_list); l != NULL;
    387 	     l = SIMPLEQ_NEXT(l, list)) {
    388 		if (l->irq != 0)
    389 			continue;
    390 		bitmap = l->bitmap;
    391 		for (i = 0; i < 16; i++) {
    392 			if ((pciirq & (1 << i)) != 0 &&
    393 			    (bitmap & (1 << i)) != 0) {
    394 				/*
    395 				 * This IRQ is a valid PCI IRQ already
    396 				 * connected to another PIRQ, and also an
    397 				 * IRQ our PIRQ can use; connect it up!
    398 				 */
    399 				l->irq = i;
    400 				l->old_irq = 0xff;
    401 				l->fixup_stage = 2;
    402 #ifdef PCIINTR_DEBUG
    403 				printf("pciintr_link_fixup: assigning "
    404 				       "IRQ %d to PIRQ %d\n", l->irq,
    405 				       l->clink);
    406 #endif
    407 				break;
    408 			}
    409 		}
    410 	}
    411 
    412 #ifdef PCIBIOS_IRQS_HINT
    413 	/*
    414 	 * Stage 3: The worst case. I need configuration hint that
    415 	 * user supplied a mask for the PCI irqs
    416 	 */
    417 	pciirq = PCIBIOS_IRQS_HINT;
    418 	for (l = SIMPLEQ_FIRST(&pciintr_link_map_list); l != NULL;
    419 	     l = SIMPLEQ_NEXT(l, list)) {
    420 		if (l->irq != 0)
    421 			continue;
    422 		for (i = 0; i < 16; i++) {
    423 			if ((pciirq & (1 << i)) != 0 &&
    424 			    (bitmap & (1 << i)) != 0) {
    425 				l->irq = i;
    426 				l->old_irq = 0xff;
    427 				l->fixup_stage = 3;
    428 #ifdef PCIINTR_DEBUG
    429 				printf("pciintr_link_fixup (stage 3): "
    430 				       "assigning IRQ %d to PIRQ %d\n",
    431 				       l->irq, l->clink);
    432 #endif
    433 				break;
    434 			}
    435 		}
    436 	}
    437 #endif /* PCIBIOS_IRQS_HINT */
    438 
    439 	return (0);
    440 }
    441 
    442 int
    443 pciintr_link_route(pciirq)
    444 	u_int16_t *pciirq;
    445 {
    446 	struct pciintr_link_map *l;
    447 	int rv = 0;
    448 
    449 	*pciirq = 0;
    450 
    451 	for (l = SIMPLEQ_FIRST(&pciintr_link_map_list); l != NULL;
    452 	     l = SIMPLEQ_NEXT(l, list)) {
    453 		if (pciintr_icu_set_intr(pciintr_icu_tag, pciintr_icu_handle,
    454 					 l->clink, l->irq) != 0 ||
    455 		    pciintr_icu_set_trigger(pciintr_icu_tag, pciintr_icu_handle,
    456 					    l->irq, IST_LEVEL) != 0) {
    457 			printf("pciintr_link_route: route of PIRQ %d -> IRQ %d"
    458 			    " failed\n", l->clink, l->irq);
    459 			rv = 1;
    460 		} else {
    461 			/*
    462 			 * Succssfully routed interrupt.  Mark this as
    463 			 * a PCI interrupt.
    464 			 */
    465 			*pciirq |= (1 << l->irq);
    466 		}
    467 	}
    468 
    469 	return (rv);
    470 }
    471 
    472 int
    473 pciintr_irq_release(pciirq)
    474 	u_int16_t *pciirq;
    475 {
    476 	int i;
    477 
    478 	for (i = 0; i < 16; i++) {
    479 		if ((*pciirq & (1 << i)) == 0)
    480 			(void) pciintr_icu_set_trigger(pciintr_icu_tag,
    481 			    pciintr_icu_handle, i, IST_EDGE);
    482 	}
    483 
    484 	return (0);
    485 }
    486 
    487 int
    488 pciintr_header_fixup(pc)
    489 	pci_chipset_tag_t pc;
    490 {
    491 #ifdef PCIBIOSVERBOSE
    492 	printf("--------------------------------------------\n");
    493 	printf("  device vendor product pin PIRQ   IRQ stage\n");
    494 	printf("--------------------------------------------\n");
    495 #endif
    496 	pci_device_foreach(pc, pcibios_max_bus, pciintr_do_header_fixup);
    497 #ifdef PCIBIOSVERBOSE
    498 	printf("--------------------------------------------\n");
    499 #endif
    500 
    501 	return (0);
    502 }
    503 
    504 void
    505 pciintr_do_header_fixup(pc, tag)
    506 	pci_chipset_tag_t pc;
    507 	pcitag_t tag;
    508 {
    509 	struct pcibios_intr_routing *pir;
    510 	struct pciintr_link_map *l;
    511 	int pin, irq, link;
    512 	int bus, device, function;
    513 	pcireg_t intr, id;
    514 
    515 	pci_decompose_tag(pc, tag, &bus, &device, &function);
    516 	id = pci_conf_read(pc, tag, PCI_ID_REG);
    517 
    518 	intr = pci_conf_read(pc, tag, PCI_INTERRUPT_REG);
    519 	pin = PCI_INTERRUPT_PIN(intr);
    520 	irq = PCI_INTERRUPT_LINE(intr);
    521 
    522 	if (pin == 0) {
    523 		/*
    524 		 * No interrupt used.
    525 		 */
    526 		return;
    527 	}
    528 
    529 	pir = pciintr_pir_lookup(bus, device);
    530 	if (pir == NULL || (link = pir->linkmap[pin - 1].link) == 0) {
    531 		/*
    532 		 * Interrupt not connected; no
    533 		 * need to change.
    534 		 */
    535 		return;
    536 	}
    537 
    538 	l = pciintr_link_lookup_link(link);
    539 	if (l == NULL) {
    540 		/*
    541 		 * No link map entry?!
    542 		 */
    543 		printf("pciintr_header_fixup: no entry for link 0x%02x "
    544 		       "(%d:%d:%d:%c)\n", link, bus, device, function,
    545 		       '@' + pin);
    546 		return;
    547 	}
    548 
    549 	/*
    550 	 * IRQs 14 and 15 are reserved for PCI IDE interrupts; don't muck
    551 	 * with them.
    552 	 */
    553 	if (irq == 14 || irq == 15)
    554 		return;
    555 
    556 #ifdef PCIBIOSVERBOSE
    557 	printf("%03d:%02d:%d 0x%04x 0x%04x  %c   0x%02x   %02d  %d\n",
    558 	       bus, device, function, PCI_VENDOR(id), PCI_PRODUCT(id),
    559 	       '@' + pin, l->clink, l->irq, l->fixup_stage);
    560 #endif
    561 
    562 	intr &= ~(PCI_INTERRUPT_LINE_MASK << PCI_INTERRUPT_LINE_SHIFT);
    563 	intr |= (l->irq << PCI_INTERRUPT_LINE_SHIFT);
    564 	pci_conf_write(pc, tag, PCI_INTERRUPT_REG, intr);
    565 }
    566 
    567 int
    568 pci_intr_fixup(pc, iot, pciirq)
    569 	pci_chipset_tag_t pc;
    570 	bus_space_tag_t iot;
    571 	u_int16_t *pciirq;
    572 {
    573 	const struct pciintr_icu_table *piit = NULL;
    574 	pcitag_t icutag;
    575 	pcireg_t icuid;
    576 
    577 	/*
    578 	 * Attempt to initialize our PCI interrupt router.  If
    579 	 * the PIR Table is present in ROM, use the location
    580 	 * specified by the PIR Table, and use the compat ID,
    581 	 * if present.  Otherwise, we have to look for the router
    582 	 * ourselves (the PCI-ISA bridge).
    583 	 */
    584 	if (pcibios_pir_header.signature != 0) {
    585 		icutag = pci_make_tag(pc, pcibios_pir_header.router_bus,
    586 		    (pcibios_pir_header.router_devfunc >> 3) & 0x1f,
    587 		    pcibios_pir_header.router_devfunc & 7);
    588 		icuid = pcibios_pir_header.compat_router;
    589 		if (icuid == 0 ||
    590 		    (piit = pciintr_icu_lookup(icuid)) == NULL) {
    591 			/*
    592 			 * No compat ID, or don't know the compat ID?  Read
    593 			 * it from the configuration header.
    594 			 */
    595 			icuid = pci_conf_read(pc, icutag, PCI_ID_REG);
    596 		}
    597 		if (piit == NULL)
    598 			piit = pciintr_icu_lookup(icuid);
    599 	} else {
    600 		int device, maxdevs = pci_bus_maxdevs(pc, 0);
    601 
    602 		/*
    603 		 * Search configuration space for a known interrupt
    604 		 * router.
    605 		 */
    606 		for (device = 0; device < maxdevs; device++) {
    607 			icutag = pci_make_tag(pc, 0, device, 0);
    608 			icuid = pci_conf_read(pc, icutag, PCI_ID_REG);
    609 
    610 			/* Invalid vendor ID value? */
    611 			if (PCI_VENDOR(icuid) == PCI_VENDOR_INVALID)
    612 				continue;
    613 			/* XXX Not invalid, but we've done this ~forever. */
    614 			if (PCI_VENDOR(icuid) == 0)
    615 				continue;
    616 
    617 			piit = pciintr_icu_lookup(icuid);
    618 			if (piit != NULL)
    619 				break;
    620 		}
    621 	}
    622 
    623 	if (piit == NULL) {
    624 		printf("pci_intr_fixup: no compatible PCI ICU found\n");
    625 		return (-1);		/* non-fatal */
    626 	}
    627 
    628 	/*
    629 	 * Initialize the PCI ICU.
    630 	 */
    631 	if ((*piit->piit_init)(pc, iot, icutag, &pciintr_icu_tag,
    632 	    &pciintr_icu_handle) != 0)
    633 		return (-1);		/* non-fatal */
    634 
    635 	/*
    636 	 * Initialize the PCI interrupt link map.
    637 	 */
    638 	if (pciintr_link_init())
    639 		return (-1);		/* non-fatal */
    640 
    641 	/*
    642 	 * Fix up the link->IRQ mappings.
    643 	 */
    644 	if (pciintr_link_fixup() != 0)
    645 		return (-1);		/* non-fatal */
    646 
    647 	/*
    648 	 * Now actually program the PCI ICU with the new
    649 	 * routing information.
    650 	 */
    651 	if (pciintr_link_route(pciirq) != 0)
    652 		return (1);		/* fatal */
    653 
    654 	/*
    655 	 * Now that we've routed all of the PIRQs, rewrite the PCI
    656 	 * configuration headers to reflect the new mapping.
    657 	 */
    658 	if (pciintr_header_fixup(pc) != 0)
    659 		return (1);		/* fatal */
    660 
    661 	/*
    662 	 * Free any unused PCI IRQs for ISA devices.
    663 	 */
    664 	if (pciintr_irq_release(pciirq) != 0)
    665 		return (-1);		/* non-fatal */
    666 
    667 	/*
    668 	 * All done!
    669 	 */
    670 	return (0);			/* success! */
    671 }
    672