1/*-
2 * Copyright (c) 1997, Stefan Esser <se@freebsd.org>
3 * Copyright (c) 2000, Michael Smith <msmith@freebsd.org>
4 * Copyright (c) 2000, BSDi
5 * Copyright (c) 2004, John Baldwin <jhb@FreeBSD.org>
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice unmodified, this list of conditions, and the following
13 *    disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 *    notice, this list of conditions and the following disclaimer in the
16 *    documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
19 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
20 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
21 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
22 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
23 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
27 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28 */
29
30#include <sys/cdefs.h>
31__FBSDID("$FreeBSD$");
32
33#include <sys/param.h>
34#include <sys/systm.h>
35#include <sys/bus.h>
36#include <sys/kernel.h>
37#include <sys/malloc.h>
38#include <sys/module.h>
39#include <sys/sysctl.h>
40#include <vm/vm.h>
41#include <vm/pmap.h>
42#include <vm/vm_param.h>
43#include <machine/md_var.h>
44#include <dev/pci/pcivar.h>
45#include <dev/pci/pcireg.h>
46#include <machine/pci_cfgreg.h>
47#include <machine/segments.h>
48#include <machine/pc/bios.h>
49
50#define	NUM_ISA_INTERRUPTS	16
51
52/*
53 * A link device.  Loosely based on the ACPI PCI link device.  This doesn't
54 * try to support priorities for different ISA interrupts.
55 */
56struct pci_link {
57	TAILQ_ENTRY(pci_link) pl_links;
58	uint8_t		pl_id;
59	uint8_t		pl_irq;
60	uint16_t	pl_irqmask;
61	int		pl_references;
62	int		pl_routed;
63};
64
65struct pci_link_lookup {
66	struct pci_link	**pci_link_ptr;
67	int		bus;
68	int		device;
69	int		pin;
70};
71
72struct pci_dev_lookup {
73	uint8_t		link;
74	int		bus;
75	int		device;
76	int		pin;
77};
78
79typedef void pir_entry_handler(struct PIR_entry *entry,
80    struct PIR_intpin* intpin, void *arg);
81
82static void	pci_print_irqmask(u_int16_t irqs);
83static int	pci_pir_biosroute(int bus, int device, int func, int pin,
84		    int irq);
85static int	pci_pir_choose_irq(struct pci_link *pci_link, int irqmask);
86static void	pci_pir_create_links(struct PIR_entry *entry,
87		    struct PIR_intpin *intpin, void *arg);
88static void	pci_pir_dump_links(void);
89static struct pci_link *pci_pir_find_link(uint8_t link_id);
90static void	pci_pir_find_link_handler(struct PIR_entry *entry,
91		    struct PIR_intpin *intpin, void *arg);
92static void	pci_pir_initial_irqs(struct PIR_entry *entry,
93		    struct PIR_intpin *intpin, void *arg);
94static void	pci_pir_parse(void);
95static uint8_t	pci_pir_search_irq(int bus, int device, int pin);
96static int	pci_pir_valid_irq(struct pci_link *pci_link, int irq);
97static void	pci_pir_walk_table(pir_entry_handler *handler, void *arg);
98
99static MALLOC_DEFINE(M_PIR, "$PIR", "$PIR structures");
100
101static struct PIR_table *pci_route_table;
102static device_t pir_device;
103static int pci_route_count, pir_bios_irqs, pir_parsed;
104static TAILQ_HEAD(, pci_link) pci_links;
105static int pir_interrupt_weight[NUM_ISA_INTERRUPTS];
106
107/* sysctl vars */
108SYSCTL_DECL(_hw_pci);
109
110/* XXX this likely should live in a header file */
111#ifdef PC98
112/* IRQs 3, 5, 7, 9, 10, 11, 12, 13 */
113#define PCI_IRQ_OVERRIDE_MASK 0x3e68
114#else
115/* IRQs 3, 4, 5, 6, 7, 9, 10, 11, 12, 14, 15 */
116#define PCI_IRQ_OVERRIDE_MASK 0xdef8
117#endif
118
119static uint32_t pci_irq_override_mask = PCI_IRQ_OVERRIDE_MASK;
120TUNABLE_INT("hw.pci.irq_override_mask", &pci_irq_override_mask);
121SYSCTL_INT(_hw_pci, OID_AUTO, irq_override_mask, CTLFLAG_RDTUN,
122    &pci_irq_override_mask, PCI_IRQ_OVERRIDE_MASK,
123    "Mask of allowed irqs to try to route when it has no good clue about\n"
124    "which irqs it should use.");
125
126/*
127 * Look for the interrupt routing table.
128 *
129 * We use PCI BIOS's PIR table if it's available. $PIR is the standard way
130 * to do this.  Sadly, some machines are not standards conforming and have
131 * _PIR instead.  We shrug and cope by looking for both.
132 */
133void
134pci_pir_open(void)
135{
136	struct PIR_table *pt;
137	uint32_t sigaddr;
138	int i;
139	uint8_t ck, *cv;
140
141#ifdef XEN
142	return;
143#else
144	/* Don't try if we've already found a table. */
145	if (pci_route_table != NULL)
146		return;
147
148	/* Look for $PIR and then _PIR. */
149	sigaddr = bios_sigsearch(0, "$PIR", 4, 16, 0);
150	if (sigaddr == 0)
151		sigaddr = bios_sigsearch(0, "_PIR", 4, 16, 0);
152	if (sigaddr == 0)
153		return;
154#endif
155	/* If we found something, check the checksum and length. */
156	/* XXX - Use pmap_mapdev()? */
157	pt = (struct PIR_table *)(uintptr_t)BIOS_PADDRTOVADDR(sigaddr);
158	if (pt->pt_header.ph_length <= sizeof(struct PIR_header))
159		return;
160	for (cv = (u_int8_t *)pt, ck = 0, i = 0;
161	     i < (pt->pt_header.ph_length); i++)
162		ck += cv[i];
163	if (ck != 0)
164		return;
165
166	/* Ok, we've got a valid table. */
167	pci_route_table = pt;
168	pci_route_count = (pt->pt_header.ph_length -
169	    sizeof(struct PIR_header)) /
170	    sizeof(struct PIR_entry);
171}
172
173/*
174 * Find the pci_link structure for a given link ID.
175 */
176static struct pci_link *
177pci_pir_find_link(uint8_t link_id)
178{
179	struct pci_link *pci_link;
180
181	TAILQ_FOREACH(pci_link, &pci_links, pl_links) {
182		if (pci_link->pl_id == link_id)
183			return (pci_link);
184	}
185	return (NULL);
186}
187
188/*
189 * Find the link device associated with a PCI device in the table.
190 */
191static void
192pci_pir_find_link_handler(struct PIR_entry *entry, struct PIR_intpin *intpin,
193    void *arg)
194{
195	struct pci_link_lookup *lookup;
196
197	lookup = (struct pci_link_lookup *)arg;
198	if (entry->pe_bus == lookup->bus &&
199	    entry->pe_device == lookup->device &&
200	    intpin - entry->pe_intpin == lookup->pin)
201		*lookup->pci_link_ptr = pci_pir_find_link(intpin->link);
202}
203
204/*
205 * Check to see if a possible IRQ setting is valid.
206 */
207static int
208pci_pir_valid_irq(struct pci_link *pci_link, int irq)
209{
210
211	if (!PCI_INTERRUPT_VALID(irq))
212		return (0);
213	return (pci_link->pl_irqmask & (1 << irq));
214}
215
216/*
217 * Walk the $PIR executing the worker function for each valid intpin entry
218 * in the table.  The handler is passed a pointer to both the entry and
219 * the intpin in the entry.
220 */
221static void
222pci_pir_walk_table(pir_entry_handler *handler, void *arg)
223{
224	struct PIR_entry *entry;
225	struct PIR_intpin *intpin;
226	int i, pin;
227
228	entry = &pci_route_table->pt_entry[0];
229	for (i = 0; i < pci_route_count; i++, entry++) {
230		intpin = &entry->pe_intpin[0];
231		for (pin = 0; pin < 4; pin++, intpin++)
232			if (intpin->link != 0)
233				handler(entry, intpin, arg);
234	}
235}
236
237static void
238pci_pir_create_links(struct PIR_entry *entry, struct PIR_intpin *intpin,
239    void *arg)
240{
241	struct pci_link *pci_link;
242
243	pci_link = pci_pir_find_link(intpin->link);
244	if (pci_link != NULL) {
245		pci_link->pl_references++;
246		if (intpin->irqs != pci_link->pl_irqmask) {
247			if (bootverbose)
248				printf(
249	"$PIR: Entry %d.%d.INT%c has different mask for link %#x, merging\n",
250				    entry->pe_bus, entry->pe_device,
251				    (intpin - entry->pe_intpin) + 'A',
252				    pci_link->pl_id);
253			pci_link->pl_irqmask &= intpin->irqs;
254		}
255	} else {
256		pci_link = malloc(sizeof(struct pci_link), M_PIR, M_WAITOK);
257		pci_link->pl_id = intpin->link;
258		pci_link->pl_irqmask = intpin->irqs;
259		pci_link->pl_irq = PCI_INVALID_IRQ;
260		pci_link->pl_references = 1;
261		pci_link->pl_routed = 0;
262		TAILQ_INSERT_TAIL(&pci_links, pci_link, pl_links);
263	}
264}
265
266/*
267 * Look to see if any of the function on the PCI device at bus/device have
268 * an interrupt routed to intpin 'pin' by the BIOS.
269 */
270static uint8_t
271pci_pir_search_irq(int bus, int device, int pin)
272{
273	uint32_t value;
274	uint8_t func, maxfunc;
275
276	/* See if we have a valid device at function 0. */
277	value = pci_cfgregread(bus, device, 0, PCIR_HDRTYPE, 1);
278	if ((value & PCIM_HDRTYPE) > PCI_MAXHDRTYPE)
279		return (PCI_INVALID_IRQ);
280	if (value & PCIM_MFDEV)
281		maxfunc = PCI_FUNCMAX;
282	else
283		maxfunc = 0;
284
285	/* Scan all possible functions at this device. */
286	for (func = 0; func <= maxfunc; func++) {
287		value = pci_cfgregread(bus, device, func, PCIR_DEVVENDOR, 4);
288		if (value == 0xffffffff)
289			continue;
290		value = pci_cfgregread(bus, device, func, PCIR_INTPIN, 1);
291
292		/*
293		 * See if it uses the pin in question.  Note that the passed
294		 * in pin uses 0 for A, .. 3 for D whereas the intpin
295		 * register uses 0 for no interrupt, 1 for A, .. 4 for D.
296		 */
297		if (value != pin + 1)
298			continue;
299		value = pci_cfgregread(bus, device, func, PCIR_INTLINE, 1);
300		if (bootverbose)
301			printf(
302		"$PIR: Found matching pin for %d.%d.INT%c at func %d: %d\n",
303			    bus, device, pin + 'A', func, value);
304		if (value != PCI_INVALID_IRQ)
305			return (value);
306	}
307	return (PCI_INVALID_IRQ);
308}
309
310/*
311 * Try to initialize IRQ based on this device's IRQ.
312 */
313static void
314pci_pir_initial_irqs(struct PIR_entry *entry, struct PIR_intpin *intpin,
315    void *arg)
316{
317	struct pci_link *pci_link;
318	uint8_t irq, pin;
319
320	pin = intpin - entry->pe_intpin;
321	pci_link = pci_pir_find_link(intpin->link);
322	irq = pci_pir_search_irq(entry->pe_bus, entry->pe_device, pin);
323	if (irq == PCI_INVALID_IRQ || irq == pci_link->pl_irq)
324		return;
325
326	/* Don't trust any BIOS IRQs greater than 15. */
327	if (irq >= NUM_ISA_INTERRUPTS) {
328		printf(
329	"$PIR: Ignoring invalid BIOS IRQ %d from %d.%d.INT%c for link %#x\n",
330		    irq, entry->pe_bus, entry->pe_device, pin + 'A',
331		    pci_link->pl_id);
332		return;
333	}
334
335	/*
336	 * If we don't have an IRQ for this link yet, then we trust the
337	 * BIOS, even if it seems invalid from the $PIR entries.
338	 */
339	if (pci_link->pl_irq == PCI_INVALID_IRQ) {
340		if (!pci_pir_valid_irq(pci_link, irq))
341			printf(
342	"$PIR: Using invalid BIOS IRQ %d from %d.%d.INT%c for link %#x\n",
343			    irq, entry->pe_bus, entry->pe_device, pin + 'A',
344			    pci_link->pl_id);
345		pci_link->pl_irq = irq;
346		pci_link->pl_routed = 1;
347		return;
348	}
349
350	/*
351	 * We have an IRQ and it doesn't match the current IRQ for this
352	 * link.  If the new IRQ is invalid, then warn about it and ignore
353	 * it.  If the old IRQ is invalid and the new IRQ is valid, then
354	 * prefer the new IRQ instead.  If both IRQs are valid, then just
355	 * use the first one.  Note that if we ever get into this situation
356	 * we are having to guess which setting the BIOS actually routed.
357	 * Perhaps we should just give up instead.
358	 */
359	if (!pci_pir_valid_irq(pci_link, irq)) {
360		printf(
361		"$PIR: BIOS IRQ %d for %d.%d.INT%c is not valid for link %#x\n",
362		    irq, entry->pe_bus, entry->pe_device, pin + 'A',
363		    pci_link->pl_id);
364	} else if (!pci_pir_valid_irq(pci_link, pci_link->pl_irq)) {
365		printf(
366"$PIR: Preferring valid BIOS IRQ %d from %d.%d.INT%c for link %#x to IRQ %d\n",
367		    irq, entry->pe_bus, entry->pe_device, pin + 'A',
368		    pci_link->pl_id, pci_link->pl_irq);
369		pci_link->pl_irq = irq;
370		pci_link->pl_routed = 1;
371	} else
372		printf(
373	"$PIR: BIOS IRQ %d for %d.%d.INT%c does not match link %#x irq %d\n",
374		    irq, entry->pe_bus, entry->pe_device, pin + 'A',
375		    pci_link->pl_id, pci_link->pl_irq);
376}
377
378/*
379 * Parse $PIR to enumerate link devices and attempt to determine their
380 * initial state.  This could perhaps be cleaner if we had drivers for the
381 * various interrupt routers as they could read the initial IRQ for each
382 * link.
383 */
384static void
385pci_pir_parse(void)
386{
387	char tunable_buffer[64];
388	struct pci_link *pci_link;
389	int i, irq;
390
391	/* Only parse once. */
392	if (pir_parsed)
393		return;
394	pir_parsed = 1;
395
396	/* Enumerate link devices. */
397	TAILQ_INIT(&pci_links);
398	pci_pir_walk_table(pci_pir_create_links, NULL);
399	if (bootverbose) {
400		printf("$PIR: Links after initial probe:\n");
401		pci_pir_dump_links();
402	}
403
404	/*
405	 * Check to see if the BIOS has already routed any of the links by
406	 * checking each device connected to each link to see if it has a
407	 * valid IRQ.
408	 */
409	pci_pir_walk_table(pci_pir_initial_irqs, NULL);
410	if (bootverbose) {
411		printf("$PIR: Links after initial IRQ discovery:\n");
412		pci_pir_dump_links();
413	}
414
415	/*
416	 * Allow the user to override the IRQ for a given link device.  We
417	 * allow invalid IRQs to be specified but warn about them.  An IRQ
418	 * of 255 or 0 clears any preset IRQ.
419	 */
420	i = 0;
421	TAILQ_FOREACH(pci_link, &pci_links, pl_links) {
422		snprintf(tunable_buffer, sizeof(tunable_buffer),
423		    "hw.pci.link.%#x.irq", pci_link->pl_id);
424		if (getenv_int(tunable_buffer, &irq) == 0)
425			continue;
426		if (irq == 0)
427			irq = PCI_INVALID_IRQ;
428		if (irq != PCI_INVALID_IRQ &&
429		    !pci_pir_valid_irq(pci_link, irq) && bootverbose)
430			printf(
431		"$PIR: Warning, IRQ %d for link %#x is not listed as valid\n",
432			    irq, pci_link->pl_id);
433		pci_link->pl_routed = 0;
434		pci_link->pl_irq = irq;
435		i = 1;
436	}
437	if (bootverbose && i) {
438		printf("$PIR: Links after tunable overrides:\n");
439		pci_pir_dump_links();
440	}
441
442	/*
443	 * Build initial interrupt weights as well as bitmap of "known-good"
444	 * IRQs that the BIOS has already used for PCI link devices.
445	 */
446	TAILQ_FOREACH(pci_link, &pci_links, pl_links) {
447		if (!PCI_INTERRUPT_VALID(pci_link->pl_irq))
448			continue;
449		pir_bios_irqs |= 1 << pci_link->pl_irq;
450		pir_interrupt_weight[pci_link->pl_irq] +=
451		    pci_link->pl_references;
452	}
453	if (bootverbose) {
454		printf("$PIR: IRQs used by BIOS: ");
455		pci_print_irqmask(pir_bios_irqs);
456		printf("\n");
457		printf("$PIR: Interrupt Weights:\n[ ");
458		for (i = 0; i < NUM_ISA_INTERRUPTS; i++)
459			printf(" %3d", i);
460		printf(" ]\n[ ");
461		for (i = 0; i < NUM_ISA_INTERRUPTS; i++)
462			printf(" %3d", pir_interrupt_weight[i]);
463		printf(" ]\n");
464	}
465}
466
467/*
468 * Use the PCI BIOS to route an interrupt for a given device.
469 *
470 * Input:
471 * AX = PCIBIOS_ROUTE_INTERRUPT
472 * BH = bus
473 * BL = device [7:3] / function [2:0]
474 * CH = IRQ
475 * CL = Interrupt Pin (0x0A = A, ... 0x0D = D)
476 */
477static int
478pci_pir_biosroute(int bus, int device, int func, int pin, int irq)
479{
480	struct bios_regs args;
481
482	args.eax = PCIBIOS_ROUTE_INTERRUPT;
483	args.ebx = (bus << 8) | (device << 3) | func;
484	args.ecx = (irq << 8) | (0xa + pin);
485#ifdef XEN
486	return (0);
487#else
488	return (bios32(&args, PCIbios.ventry, GSEL(GCODE_SEL, SEL_KPL)));
489#endif
490}
491
492
493/*
494 * Route a PCI interrupt using a link device from the $PIR.
495 */
496int
497pci_pir_route_interrupt(int bus, int device, int func, int pin)
498{
499	struct pci_link_lookup lookup;
500	struct pci_link *pci_link;
501	int error, irq;
502
503	if (pci_route_table == NULL)
504		return (PCI_INVALID_IRQ);
505
506	/* Lookup link device for this PCI device/pin. */
507	pci_link = NULL;
508	lookup.bus = bus;
509	lookup.device = device;
510	lookup.pin = pin - 1;
511	lookup.pci_link_ptr = &pci_link;
512	pci_pir_walk_table(pci_pir_find_link_handler, &lookup);
513	if (pci_link == NULL) {
514		printf("$PIR: No matching entry for %d.%d.INT%c\n", bus,
515		    device, pin - 1 + 'A');
516		return (PCI_INVALID_IRQ);
517	}
518
519	/*
520	 * Pick a new interrupt if we don't have one already.  We look
521	 * for an interrupt from several different sets.  First, if
522	 * this link only has one valid IRQ, use that.  Second, we
523	 * check the set of PCI only interrupts from the $PIR.  Third,
524	 * we check the set of known-good interrupts that the BIOS has
525	 * already used.  Lastly, we check the "all possible valid
526	 * IRQs" set.
527	 */
528	if (!PCI_INTERRUPT_VALID(pci_link->pl_irq)) {
529		if (pci_link->pl_irqmask != 0 && powerof2(pci_link->pl_irqmask))
530			irq = ffs(pci_link->pl_irqmask) - 1;
531		else
532			irq = pci_pir_choose_irq(pci_link,
533			    pci_route_table->pt_header.ph_pci_irqs);
534		if (!PCI_INTERRUPT_VALID(irq))
535			irq = pci_pir_choose_irq(pci_link, pir_bios_irqs);
536		if (!PCI_INTERRUPT_VALID(irq))
537			irq = pci_pir_choose_irq(pci_link,
538			    pci_irq_override_mask);
539		if (!PCI_INTERRUPT_VALID(irq)) {
540			if (bootverbose)
541				printf(
542			"$PIR: Failed to route interrupt for %d:%d INT%c\n",
543				    bus, device, pin - 1 + 'A');
544			return (PCI_INVALID_IRQ);
545		}
546		pci_link->pl_irq = irq;
547	}
548
549	/* Ask the BIOS to route this IRQ if we haven't done so already. */
550	if (!pci_link->pl_routed) {
551		error = pci_pir_biosroute(bus, device, func, pin - 1,
552		    pci_link->pl_irq);
553
554		/* Ignore errors when routing a unique interrupt. */
555		if (error && !powerof2(pci_link->pl_irqmask)) {
556			printf("$PIR: ROUTE_INTERRUPT failed.\n");
557			return (PCI_INVALID_IRQ);
558		}
559		pci_link->pl_routed = 1;
560
561		/* Ensure the interrupt is set to level/low trigger. */
562		KASSERT(pir_device != NULL, ("missing pir device"));
563		BUS_CONFIG_INTR(pir_device, pci_link->pl_irq,
564		    INTR_TRIGGER_LEVEL, INTR_POLARITY_LOW);
565	}
566	if (bootverbose)
567		printf("$PIR: %d:%d INT%c routed to irq %d\n", bus, device,
568		    pin - 1 + 'A', pci_link->pl_irq);
569	return (pci_link->pl_irq);
570}
571
572/*
573 * Try to pick an interrupt for the specified link from the interrupts
574 * set in the mask.
575 */
576static int
577pci_pir_choose_irq(struct pci_link *pci_link, int irqmask)
578{
579	int i, irq, realmask;
580
581	/* XXX: Need to have a #define of known bad IRQs to also mask out? */
582	realmask = pci_link->pl_irqmask & irqmask;
583	if (realmask == 0)
584		return (PCI_INVALID_IRQ);
585
586	/* Find IRQ with lowest weight. */
587	irq = PCI_INVALID_IRQ;
588	for (i = 0; i < NUM_ISA_INTERRUPTS; i++) {
589		if (!(realmask & 1 << i))
590			continue;
591		if (irq == PCI_INVALID_IRQ ||
592		    pir_interrupt_weight[i] < pir_interrupt_weight[irq])
593			irq = i;
594	}
595	if (bootverbose && PCI_INTERRUPT_VALID(irq)) {
596		printf("$PIR: Found IRQ %d for link %#x from ", irq,
597		    pci_link->pl_id);
598		pci_print_irqmask(realmask);
599		printf("\n");
600	}
601	return (irq);
602}
603
604static void
605pci_print_irqmask(u_int16_t irqs)
606{
607	int i, first;
608
609	if (irqs == 0) {
610		printf("none");
611		return;
612	}
613	first = 1;
614	for (i = 0; i < 16; i++, irqs >>= 1)
615		if (irqs & 1) {
616			if (!first)
617				printf(" ");
618			else
619				first = 0;
620			printf("%d", i);
621		}
622}
623
624/*
625 * Display link devices.
626 */
627static void
628pci_pir_dump_links(void)
629{
630	struct pci_link *pci_link;
631
632	printf("Link  IRQ  Rtd  Ref  IRQs\n");
633	TAILQ_FOREACH(pci_link, &pci_links, pl_links) {
634		printf("%#4x  %3d   %c   %3d  ", pci_link->pl_id,
635		    pci_link->pl_irq, pci_link->pl_routed ? 'Y' : 'N',
636		    pci_link->pl_references);
637		pci_print_irqmask(pci_link->pl_irqmask);
638		printf("\n");
639	}
640}
641
642/*
643 * See if any interrupts for a given PCI bus are routed in the PIR.  Don't
644 * even bother looking if the BIOS doesn't support routing anyways.  If we
645 * are probing a PCI-PCI bridge, then require_parse will be true and we should
646 * only succeed if a host-PCI bridge has already attached and parsed the PIR.
647 */
648int
649pci_pir_probe(int bus, int require_parse)
650{
651	int i;
652
653	if (pci_route_table == NULL || (require_parse && !pir_parsed))
654		return (0);
655	for (i = 0; i < pci_route_count; i++)
656		if (pci_route_table->pt_entry[i].pe_bus == bus)
657			return (1);
658	return (0);
659}
660
661/*
662 * The driver for the new-bus psuedo device pir0 for the $PIR table.
663 */
664
665static int
666pir_probe(device_t dev)
667{
668	char buf[64];
669
670	snprintf(buf, sizeof(buf), "PCI Interrupt Routing Table: %d Entries",
671	    pci_route_count);
672	device_set_desc_copy(dev, buf);
673	return (0);
674}
675
676static int
677pir_attach(device_t dev)
678{
679
680	pci_pir_parse();
681	KASSERT(pir_device == NULL, ("Multiple pir devices"));
682	pir_device = dev;
683	return (0);
684}
685
686static void
687pir_resume_find_device(struct PIR_entry *entry, struct PIR_intpin *intpin,
688    void *arg)
689{
690	struct pci_dev_lookup *pd;
691
692	pd = (struct pci_dev_lookup *)arg;
693	if (intpin->link != pd->link || pd->bus != -1)
694		return;
695	pd->bus = entry->pe_bus;
696	pd->device = entry->pe_device;
697	pd->pin = intpin - entry->pe_intpin;
698}
699
700static int
701pir_resume(device_t dev)
702{
703	struct pci_dev_lookup pd;
704	struct pci_link *pci_link;
705	int error;
706
707	/* Ask the BIOS to re-route each link that was already routed. */
708	TAILQ_FOREACH(pci_link, &pci_links, pl_links) {
709		if (!PCI_INTERRUPT_VALID(pci_link->pl_irq)) {
710			KASSERT(!pci_link->pl_routed,
711			    ("link %#x is routed but has invalid PCI IRQ",
712			    pci_link->pl_id));
713			continue;
714		}
715		if (pci_link->pl_routed) {
716			pd.bus = -1;
717			pd.link = pci_link->pl_id;
718			pci_pir_walk_table(pir_resume_find_device, &pd);
719			KASSERT(pd.bus != -1,
720		("did not find matching entry for link %#x in the $PIR table",
721			    pci_link->pl_id));
722			if (bootverbose)
723				device_printf(dev,
724			    "Using %d.%d.INT%c to route link %#x to IRQ %d\n",
725				    pd.bus, pd.device, pd.pin + 'A',
726				    pci_link->pl_id, pci_link->pl_irq);
727			error = pci_pir_biosroute(pd.bus, pd.device, 0, pd.pin,
728			    pci_link->pl_irq);
729			if (error)
730				device_printf(dev,
731			    "ROUTE_INTERRUPT on resume for link %#x failed.\n",
732				    pci_link->pl_id);
733		}
734	}
735	return (0);
736}
737
738static device_method_t pir_methods[] = {
739	/* Device interface */
740	DEVMETHOD(device_probe,		pir_probe),
741	DEVMETHOD(device_attach,	pir_attach),
742	DEVMETHOD(device_resume,	pir_resume),
743
744	{ 0, 0 }
745};
746
747static driver_t pir_driver = {
748	"pir",
749	pir_methods,
750	1,
751};
752
753static devclass_t pir_devclass;
754
755DRIVER_MODULE(pir, legacy, pir_driver, pir_devclass, 0, 0);
756