bios.c revision 121995 
1/*-
2 * Copyright (c) 1997 Michael Smith
3 * Copyright (c) 1998 Jonathan Lemon
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28#include <sys/cdefs.h>
29__FBSDID("$FreeBSD: head/sys/amd64/amd64/bios.c 121995 2003-11-03 22:22:04Z jhb $");
30
31/*
32 * Code for dealing with the BIOS in x86 PC systems.
33 */
34
35#include "opt_isa.h"
36
37#include <sys/param.h>
38#include <sys/systm.h>
39#include <sys/kernel.h>
40#include <sys/malloc.h>
41#include <sys/bus.h>
42#include <sys/pcpu.h>
43#include <vm/vm.h>
44#include <vm/pmap.h>
45#include <machine/md_var.h>
46#include <machine/segments.h>
47#include <machine/stdarg.h>
48#include <machine/vmparam.h>
49#include <machine/pc/bios.h>
50#ifdef DEV_ISA
51#include <isa/isavar.h>
52#include <isa/pnpreg.h>
53#include <isa/pnpvar.h>
54#endif
55
56#define BIOS_START	0xe0000
57#define BIOS_SIZE	0x20000
58
59/* exported lookup results */
60struct bios32_SDentry		PCIbios;
61struct PnPBIOS_table		*PnPBIOStable;
62
63static u_int			bios32_SDCI;
64
65/* start fairly early */
66static void			bios32_init(void *junk);
67SYSINIT(bios32, SI_SUB_CPU, SI_ORDER_ANY, bios32_init, NULL);
68
69/*
70 * bios32_init
71 *
72 * Locate various bios32 entities.
73 */
74static void
75bios32_init(void *junk)
76{
77    u_long			sigaddr;
78    struct bios32_SDheader	*sdh;
79    struct PnPBIOS_table	*pt;
80    u_int8_t			ck, *cv;
81    int				i;
82    char			*p;
83
84    /*
85     * BIOS32 Service Directory, PCI BIOS
86     */
87
88    /* look for the signature */
89    if ((sigaddr = bios_sigsearch(0, "_32_", 4, 16, 0)) != 0) {
90
91	/* get a virtual pointer to the structure */
92	sdh = (struct bios32_SDheader *)(uintptr_t)BIOS_PADDRTOVADDR(sigaddr);
93	for (cv = (u_int8_t *)sdh, ck = 0, i = 0; i < (sdh->len * 16); i++) {
94	    ck += cv[i];
95	}
96	/* If checksum is OK, enable use of the entrypoint */
97	if ((ck == 0) && (BIOS_START <= sdh->entry ) &&
98	    (sdh->entry < (BIOS_START + BIOS_SIZE))) {
99	    bios32_SDCI = BIOS_PADDRTOVADDR(sdh->entry);
100	    if (bootverbose) {
101		printf("bios32: Found BIOS32 Service Directory header at %p\n", sdh);
102		printf("bios32: Entry = 0x%x (%x)  Rev = %d  Len = %d\n",
103		       sdh->entry, bios32_SDCI, sdh->revision, sdh->len);
104	    }
105
106	    /* Allow user override of PCI BIOS search */
107	    if (((p = getenv("machdep.bios.pci")) == NULL) || strcmp(p, "disable")) {
108
109		/* See if there's a PCI BIOS entrypoint here */
110		PCIbios.ident.id = 0x49435024;	/* PCI systems should have this */
111		if (!bios32_SDlookup(&PCIbios) && bootverbose)
112		    printf("pcibios: PCI BIOS entry at 0x%x+0x%x\n", PCIbios.base, PCIbios.entry);
113	    }
114	    if (p != NULL)
115		    freeenv(p);
116	} else {
117	    printf("bios32: Bad BIOS32 Service Directory\n");
118	}
119    }
120
121    /*
122     * PnP BIOS
123     *
124     * Allow user override of PnP BIOS search
125     */
126    if ((((p = getenv("machdep.bios.pnp")) == NULL) || strcmp(p, "disable")) &&
127	((sigaddr = bios_sigsearch(0, "$PnP", 4, 16, 0)) != 0)) {
128
129	/* get a virtual pointer to the structure */
130	pt = (struct PnPBIOS_table *)(uintptr_t)BIOS_PADDRTOVADDR(sigaddr);
131	for (cv = (u_int8_t *)pt, ck = 0, i = 0; i < pt->len; i++) {
132	    ck += cv[i];
133	}
134	/* If checksum is OK, enable use of the entrypoint */
135	if (ck == 0) {
136	    PnPBIOStable = pt;
137	    if (bootverbose) {
138		printf("pnpbios: Found PnP BIOS data at %p\n", pt);
139		printf("pnpbios: Entry = %x:%x  Rev = %d.%d\n",
140		       pt->pmentrybase, pt->pmentryoffset, pt->version >> 4, pt->version & 0xf);
141		if ((pt->control & 0x3) == 0x01)
142		    printf("pnpbios: Event flag at %x\n", pt->evflagaddr);
143		if (pt->oemdevid != 0)
144		    printf("pnpbios: OEM ID %x\n", pt->oemdevid);
145
146	    }
147	} else {
148	    printf("pnpbios: Bad PnP BIOS data checksum\n");
149	}
150    }
151    if (p != NULL)
152	    freeenv(p);
153    if (bootverbose) {
154	    /* look for other know signatures */
155	    printf("Other BIOS signatures found:\n");
156    }
157}
158
159/*
160 * bios32_SDlookup
161 *
162 * Query the BIOS32 Service Directory for the service named in (ent),
163 * returns nonzero if the lookup fails.  The caller must fill in
164 * (ent->ident), the remainder are populated on a successful lookup.
165 */
166int
167bios32_SDlookup(struct bios32_SDentry *ent)
168{
169    struct bios_regs args;
170
171    if (bios32_SDCI == 0)
172	return (1);
173
174    args.eax = ent->ident.id;		/* set up arguments */
175    args.ebx = args.ecx = args.edx = 0;
176    bios32(&args, bios32_SDCI, GSEL(GCODE_SEL, SEL_KPL));
177    if ((args.eax & 0xff) == 0) {	/* success? */
178	ent->base = args.ebx;
179	ent->len = args.ecx;
180	ent->entry = args.edx;
181	ent->ventry = BIOS_PADDRTOVADDR(ent->base + ent->entry);
182	return (0);			/* all OK */
183    }
184    return (1);				/* failed */
185}
186
187
188/*
189 * bios_sigsearch
190 *
191 * Search some or all of the BIOS region for a signature string.
192 *
193 * (start)	Optional offset returned from this function
194 *		(for searching for multiple matches), or NULL
195 *		to start the search from the base of the BIOS.
196 *		Note that this will be a _physical_ address in
197 *		the range 0xe0000 - 0xfffff.
198 * (sig)	is a pointer to the byte(s) of the signature.
199 * (siglen)	number of bytes in the signature.
200 * (paralen)	signature paragraph (alignment) size.
201 * (sigofs)	offset of the signature within the paragraph.
202 *
203 * Returns the _physical_ address of the found signature, 0 if the
204 * signature was not found.
205 */
206
207u_int32_t
208bios_sigsearch(u_int32_t start, u_char *sig, int siglen, int paralen, int sigofs)
209{
210    u_char	*sp, *end;
211
212    /* compute the starting address */
213    if ((start >= BIOS_START) && (start <= (BIOS_START + BIOS_SIZE))) {
214	sp = (char *)BIOS_PADDRTOVADDR(start);
215    } else if (start == 0) {
216	sp = (char *)BIOS_PADDRTOVADDR(BIOS_START);
217    } else {
218	return 0;				/* bogus start address */
219    }
220
221    /* compute the end address */
222    end = (u_char *)BIOS_PADDRTOVADDR(BIOS_START + BIOS_SIZE);
223
224    /* loop searching */
225    while ((sp + sigofs + siglen) < end) {
226
227	/* compare here */
228	if (!bcmp(sp + sigofs, sig, siglen)) {
229	    /* convert back to physical address */
230	    return((u_int32_t)BIOS_VADDRTOPADDR(sp));
231	}
232	sp += paralen;
233    }
234    return(0);
235}
236
237/*
238 * do not staticize, used by bioscall.s
239 */
240union {
241    struct {
242	u_short	offset;
243	u_short	segment;
244    } vec16;
245    struct {
246	u_int	offset;
247	u_short	segment;
248    } vec32;
249} bioscall_vector;			/* bios jump vector */
250
251void
252set_bios_selectors(struct bios_segments *seg, int flags)
253{
254    struct soft_segment_descriptor ssd = {
255	0,			/* segment base address (overwritten) */
256	0,			/* length (overwritten) */
257	SDT_MEMERA,		/* segment type (overwritten) */
258	0,			/* priority level */
259	1,			/* descriptor present */
260	0, 0,
261	1,			/* descriptor size (overwritten) */
262	0			/* granularity == byte units */
263    };
264    union descriptor *p_gdt;
265
266#ifdef SMP
267    p_gdt = &gdt[PCPU_GET(cpuid) * NGDT];
268#else
269    p_gdt = gdt;
270#endif
271
272    ssd.ssd_base = seg->code32.base;
273    ssd.ssd_limit = seg->code32.limit;
274    ssdtosd(&ssd, &p_gdt[GBIOSCODE32_SEL].sd);
275
276    ssd.ssd_def32 = 0;
277    if (flags & BIOSCODE_FLAG) {
278	ssd.ssd_base = seg->code16.base;
279	ssd.ssd_limit = seg->code16.limit;
280	ssdtosd(&ssd, &p_gdt[GBIOSCODE16_SEL].sd);
281    }
282
283    ssd.ssd_type = SDT_MEMRWA;
284    if (flags & BIOSDATA_FLAG) {
285	ssd.ssd_base = seg->data.base;
286	ssd.ssd_limit = seg->data.limit;
287	ssdtosd(&ssd, &p_gdt[GBIOSDATA_SEL].sd);
288    }
289
290    if (flags & BIOSUTIL_FLAG) {
291	ssd.ssd_base = seg->util.base;
292	ssd.ssd_limit = seg->util.limit;
293	ssdtosd(&ssd, &p_gdt[GBIOSUTIL_SEL].sd);
294    }
295
296    if (flags & BIOSARGS_FLAG) {
297	ssd.ssd_base = seg->args.base;
298	ssd.ssd_limit = seg->args.limit;
299	ssdtosd(&ssd, &p_gdt[GBIOSARGS_SEL].sd);
300    }
301}
302
303extern int vm86pa;
304extern void bios16_jmp(void);
305
306/*
307 * this routine is really greedy with selectors, and uses 5:
308 *
309 * 32-bit code selector:	to return to kernel
310 * 16-bit code selector:	for running code
311 *        data selector:	for 16-bit data
312 *        util selector:	extra utility selector
313 *        args selector:	to handle pointers
314 *
315 * the util selector is set from the util16 entry in bios16_args, if a
316 * "U" specifier is seen.
317 *
318 * See <machine/pc/bios.h> for description of format specifiers
319 */
320int
321bios16(struct bios_args *args, char *fmt, ...)
322{
323    char	*p, *stack, *stack_top;
324    va_list 	ap;
325    int 	flags = BIOSCODE_FLAG | BIOSDATA_FLAG;
326    u_int 	i, arg_start, arg_end;
327    pt_entry_t	*pte;
328    pd_entry_t	*ptd;
329
330    arg_start = 0xffffffff;
331    arg_end = 0;
332
333    /*
334     * Some BIOS entrypoints attempt to copy the largest-case
335     * argument frame (in order to generalise handling for
336     * different entry types).  If our argument frame is
337     * smaller than this, the BIOS will reach off the top of
338     * our constructed stack segment.  Pad the top of the stack
339     * with some garbage to avoid this.
340     */
341    stack = (caddr_t)PAGE_SIZE - 32;
342
343    va_start(ap, fmt);
344    for (p = fmt; p && *p; p++) {
345	switch (*p) {
346	case 'p':			/* 32-bit pointer */
347	    i = va_arg(ap, u_int);
348	    arg_start = min(arg_start, i);
349	    arg_end = max(arg_end, i);
350	    flags |= BIOSARGS_FLAG;
351	    stack -= 4;
352	    break;
353
354	case 'i':			/* 32-bit integer */
355	    i = va_arg(ap, u_int);
356	    stack -= 4;
357	    break;
358
359	case 'U':			/* 16-bit selector */
360	    flags |= BIOSUTIL_FLAG;
361	    /* FALLTHROUGH */
362	case 'D':			/* 16-bit selector */
363	case 'C':			/* 16-bit selector */
364	    stack -= 2;
365	    break;
366
367	case 's':			/* 16-bit integer passed as an int */
368	    i = va_arg(ap, int);
369	    stack -= 2;
370	    break;
371
372	default:
373	    return (EINVAL);
374	}
375    }
376
377    if (flags & BIOSARGS_FLAG) {
378	if (arg_end - arg_start > ctob(16))
379	    return (EACCES);
380	args->seg.args.base = arg_start;
381	args->seg.args.limit = 0xffff;
382    }
383
384    args->seg.code32.base = (u_int)&bios16_jmp & PG_FRAME;
385    args->seg.code32.limit = 0xffff;
386
387    ptd = (pd_entry_t *)rcr3();
388#ifdef PAE
389    if (ptd == IdlePDPT)
390#else
391    if (ptd == IdlePTD)
392#endif
393    {
394	/*
395	 * no page table, so create one and install it.
396	 */
397	pte = (pt_entry_t *)malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
398	ptd = (pd_entry_t *)((u_int)IdlePTD + KERNBASE);
399	*pte = (vm86pa - PAGE_SIZE) | PG_RW | PG_V;
400	*ptd = vtophys(pte) | PG_RW | PG_V;
401    } else {
402	/*
403	 * this is a user-level page table
404	 */
405	pte = PTmap;
406	*pte = (vm86pa - PAGE_SIZE) | PG_RW | PG_V;
407    }
408    pmap_invalidate_all(kernel_pmap);	/* XXX insurance for now */
409
410    stack_top = stack;
411    va_start(ap, fmt);
412    for (p = fmt; p && *p; p++) {
413	switch (*p) {
414	case 'p':			/* 32-bit pointer */
415	    i = va_arg(ap, u_int);
416	    *(u_int *)stack = (i - arg_start) |
417		(GSEL(GBIOSARGS_SEL, SEL_KPL) << 16);
418	    stack += 4;
419	    break;
420
421	case 'i':			/* 32-bit integer */
422	    i = va_arg(ap, u_int);
423	    *(u_int *)stack = i;
424	    stack += 4;
425	    break;
426
427	case 'U':			/* 16-bit selector */
428	    *(u_short *)stack = GSEL(GBIOSUTIL_SEL, SEL_KPL);
429	    stack += 2;
430	    break;
431
432	case 'D':			/* 16-bit selector */
433	    *(u_short *)stack = GSEL(GBIOSDATA_SEL, SEL_KPL);
434	    stack += 2;
435	    break;
436
437	case 'C':			/* 16-bit selector */
438	    *(u_short *)stack = GSEL(GBIOSCODE16_SEL, SEL_KPL);
439	    stack += 2;
440	    break;
441
442	case 's':			/* 16-bit integer passed as an int */
443	    i = va_arg(ap, int);
444	    *(u_short *)stack = i;
445	    stack += 2;
446	    break;
447
448	default:
449	    return (EINVAL);
450	}
451    }
452
453    set_bios_selectors(&args->seg, flags);
454    bioscall_vector.vec16.offset = (u_short)args->entry;
455    bioscall_vector.vec16.segment = GSEL(GBIOSCODE16_SEL, SEL_KPL);
456
457    i = bios16_call(&args->r, stack_top);
458
459    if (pte == PTmap) {
460	*pte = 0;			/* remove entry */
461	/*
462	 * XXX only needs to be invlpg(0) but that doesn't work on the 386
463	 */
464	pmap_invalidate_all(kernel_pmap);
465    } else {
466	*ptd = 0;			/* remove page table */
467	/*
468	 * XXX only needs to be invlpg(0) but that doesn't work on the 386
469	 */
470	pmap_invalidate_all(kernel_pmap);
471	free(pte, M_TEMP);		/* ... and free it */
472    }
473    return (i);
474}
475
476#ifdef DEV_ISA
477/*
478 * PnP BIOS interface; enumerate devices only known to the system
479 * BIOS and save information about them for later use.
480 */
481
482struct pnp_sysdev
483{
484    u_int16_t	size;
485    u_int8_t	handle;
486    u_int32_t	devid;
487    u_int8_t	type[3];
488    u_int16_t	attrib;
489#define PNPATTR_NODISABLE	(1<<0)	/* can't be disabled */
490#define PNPATTR_NOCONFIG	(1<<1)	/* can't be configured */
491#define PNPATTR_OUTPUT		(1<<2)	/* can be primary output */
492#define PNPATTR_INPUT		(1<<3)	/* can be primary input */
493#define PNPATTR_BOOTABLE	(1<<4)	/* can be booted from */
494#define PNPATTR_DOCK		(1<<5)	/* is a docking station */
495#define PNPATTR_REMOVEABLE	(1<<6)	/* device is removeable */
496#define PNPATTR_CONFIG_STATIC	(0)
497#define PNPATTR_CONFIG_DYNAMIC	(1)
498#define PNPATTR_CONFIG_DYNONLY	(3)
499#define PNPATTR_CONFIG(a)	(((a) >> 7) & 0x3)
500    /* device-specific data comes here */
501    u_int8_t	devdata[0];
502} __packed;
503
504/* We have to cluster arguments within a 64k range for the bios16 call */
505struct pnp_sysdevargs
506{
507    u_int16_t	next;
508    struct pnp_sysdev node;
509};
510
511/*
512 * This function is called after the bus has assigned resource
513 * locations for a logical device.
514 */
515static void
516pnpbios_set_config(void *arg, struct isa_config *config, int enable)
517{
518}
519
520/*
521 * Quiz the PnP BIOS, build a list of PNP IDs and resource data.
522 */
523static void
524pnpbios_identify(driver_t *driver, device_t parent)
525{
526    struct PnPBIOS_table	*pt = PnPBIOStable;
527    struct bios_args		args;
528    struct pnp_sysdev		*pd;
529    struct pnp_sysdevargs	*pda;
530    u_int16_t			ndevs, bigdev;
531    int				error, currdev;
532    u_int8_t			*devnodebuf, tag;
533    u_int32_t			*devid, *compid;
534    int				idx, left;
535    device_t			dev;
536
537    /* no PnP BIOS information */
538    if (pt == NULL)
539	return;
540
541    /* ACPI already active */
542    if (devclass_get_softc(devclass_find("ACPI"), 0) != NULL)
543	return;
544
545    /* get count of PnP devices */
546    bzero(&args, sizeof(args));
547    args.seg.code16.base = BIOS_PADDRTOVADDR(pt->pmentrybase);
548    args.seg.code16.limit = 0xffff;		/* XXX ? */
549    args.seg.data.base = BIOS_PADDRTOVADDR(pt->pmdataseg);
550    args.seg.data.limit = 0xffff;
551    args.entry = pt->pmentryoffset;
552
553    if ((error = bios16(&args, PNP_COUNT_DEVNODES, &ndevs, &bigdev)) || (args.r.eax & 0xff))
554	printf("pnpbios: error %d/%x getting device count/size limit\n", error, args.r.eax);
555    ndevs &= 0xff;				/* clear high byte garbage */
556    if (bootverbose)
557	printf("pnpbios: %d devices, largest %d bytes\n", ndevs, bigdev);
558
559    devnodebuf = malloc(bigdev + (sizeof(struct pnp_sysdevargs) - sizeof(struct pnp_sysdev)),
560			M_DEVBUF, M_NOWAIT);
561    pda = (struct pnp_sysdevargs *)devnodebuf;
562    pd = &pda->node;
563
564    for (currdev = 0, left = ndevs; (currdev != 0xff) && (left > 0); left--) {
565
566	bzero(pd, bigdev);
567	pda->next = currdev;
568	/* get current configuration */
569	if ((error = bios16(&args, PNP_GET_DEVNODE, &pda->next, &pda->node, 1))) {
570	    printf("pnpbios: error %d making BIOS16 call\n", error);
571	    break;
572	}
573	if ((error = (args.r.eax & 0xff))) {
574	    if (bootverbose)
575		printf("pnpbios: %s 0x%x fetching node %d\n", error & 0x80 ? "error" : "warning", error, currdev);
576	    if (error & 0x80)
577		break;
578	}
579	currdev = pda->next;
580	if (pd->size < sizeof(struct pnp_sysdev)) {
581	    printf("pnpbios: bogus system node data, aborting scan\n");
582	    break;
583	}
584
585	/*
586	 * Ignore PICs so that we don't have to worry about the PICs
587	 * claiming IRQs to prevent their use.  The PIC drivers
588	 * already ensure that invalid IRQs are not used.
589	 */
590	if (!strcmp(pnp_eisaformat(pd->devid), "PNP0000"))	/* ISA PIC */
591	    continue;
592	if (!strcmp(pnp_eisaformat(pd->devid), "PNP0003"))	/* APIC */
593	    continue;
594
595	/* Add the device and parse its resources */
596	dev = BUS_ADD_CHILD(parent, ISA_ORDER_PNP, NULL, -1);
597	isa_set_vendorid(dev, pd->devid);
598	isa_set_logicalid(dev, pd->devid);
599	/*
600	 * It appears that some PnP BIOS doesn't allow us to re-enable
601	 * the embedded system device once it is disabled.  We shall
602	 * mark all system device nodes as "cannot be disabled", regardless
603	 * of actual settings in the device attribute byte.
604	 * XXX
605	isa_set_configattr(dev,
606	    ((pd->attrib & PNPATTR_NODISABLE) ?  0 : ISACFGATTR_CANDISABLE) |
607	    ((!(pd->attrib & PNPATTR_NOCONFIG) &&
608		PNPATTR_CONFIG(pd->attrib) != PNPATTR_CONFIG_STATIC)
609		? ISACFGATTR_DYNAMIC : 0));
610	 */
611	isa_set_configattr(dev,
612	    (!(pd->attrib & PNPATTR_NOCONFIG) &&
613		PNPATTR_CONFIG(pd->attrib) != PNPATTR_CONFIG_STATIC)
614		? ISACFGATTR_DYNAMIC : 0);
615	ISA_SET_CONFIG_CALLBACK(parent, dev, pnpbios_set_config, 0);
616	pnp_parse_resources(dev, &pd->devdata[0],
617			    pd->size - sizeof(struct pnp_sysdev), 0);
618	if (!device_get_desc(dev))
619	    device_set_desc_copy(dev, pnp_eisaformat(pd->devid));
620
621	/* Find device IDs */
622	devid = &pd->devid;
623	compid = NULL;
624
625	/* look for a compatible device ID too */
626	left = pd->size - sizeof(struct pnp_sysdev);
627	idx = 0;
628	while (idx < left) {
629	    tag = pd->devdata[idx++];
630	    if (PNP_RES_TYPE(tag) == 0) {
631		/* Small resource */
632		switch (PNP_SRES_NUM(tag)) {
633		case PNP_TAG_COMPAT_DEVICE:
634		    compid = (u_int32_t *)(pd->devdata + idx);
635		    if (bootverbose)
636			printf("pnpbios: node %d compat ID 0x%08x\n", pd->handle, *compid);
637		    /* FALLTHROUGH */
638		case PNP_TAG_END:
639		    idx = left;
640		    break;
641		default:
642		    idx += PNP_SRES_LEN(tag);
643		    break;
644		}
645	    } else
646		/* Large resource, skip it */
647		idx += *(u_int16_t *)(pd->devdata + idx) + 2;
648	}
649	if (bootverbose) {
650	    printf("pnpbios: handle %d device ID %s (%08x)",
651		   pd->handle, pnp_eisaformat(*devid), *devid);
652	    if (compid != NULL)
653		printf(" compat ID %s (%08x)",
654		       pnp_eisaformat(*compid), *compid);
655	    printf("\n");
656	}
657    }
658}
659
660static device_method_t pnpbios_methods[] = {
661	/* Device interface */
662	DEVMETHOD(device_identify,	pnpbios_identify),
663
664	{ 0, 0 }
665};
666
667static driver_t pnpbios_driver = {
668	"pnpbios",
669	pnpbios_methods,
670	1,			/* no softc */
671};
672
673static devclass_t pnpbios_devclass;
674
675DRIVER_MODULE(pnpbios, isa, pnpbios_driver, pnpbios_devclass, 0, 0);
676#endif /* DEV_ISA */
677