bios.c revision 55117 
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 * $FreeBSD: head/sys/amd64/amd64/bios.c 55117 1999-12-26 16:21:19Z bde $
28 */
29
30/*
31 * Code for dealing with the BIOS in x86 PC systems.
32 */
33
34#include "opt_pnp.h"
35
36#include "isa.h"
37
38#include <sys/param.h>
39#include <sys/systm.h>
40#include <sys/kernel.h>
41#include <sys/malloc.h>
42#include <sys/bus.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#include <isa/pnpreg.h>
51#include <isa/pnpvar.h>
52#if NISA > 0
53#include <isa/isavar.h>
54#endif
55
56#define BIOS_START	0xe0000
57#define BIOS_SIZE	0x20000
58
59/* exported lookup results */
60struct bios32_SDentry		PCIbios = {entry : 0};
61struct PnPBIOS_table		*PnPBIOStable = 0;
62
63static u_int			bios32_SDCI = 0;
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
83    /*
84     * BIOS32 Service Directory
85     */
86
87    /* look for the signature */
88    if ((sigaddr = bios_sigsearch(0, "_32_", 4, 16, 0)) != 0) {
89
90	/* get a virtual pointer to the structure */
91	sdh = (struct bios32_SDheader *)(uintptr_t)BIOS_PADDRTOVADDR(sigaddr);
92	for (cv = (u_int8_t *)sdh, ck = 0, i = 0; i < (sdh->len * 16); i++) {
93	    ck += cv[i];
94	}
95	/* If checksum is OK, enable use of the entrypoint */
96	if ((ck == 0) && (sdh->entry < (BIOS_START + BIOS_SIZE))) {
97	    bios32_SDCI = BIOS_PADDRTOVADDR(sdh->entry);
98	    if (bootverbose) {
99		printf("bios32: Found BIOS32 Service Directory header at %p\n", sdh);
100		printf("bios32: Entry = 0x%x (%x)  Rev = %d  Len = %d\n",
101		       sdh->entry, bios32_SDCI, sdh->revision, sdh->len);
102	    }
103	    /* See if there's a PCI BIOS entrypoint here */
104	    PCIbios.ident.id = 0x49435024;	/* PCI systems should have this */
105	    if (!bios32_SDlookup(&PCIbios) && bootverbose)
106		printf("pcibios: PCI BIOS entry at 0x%x\n", PCIbios.entry);
107	} else {
108	    printf("bios32: Bad BIOS32 Service Directory\n");
109	}
110    }
111
112    /*
113     * PnP BIOS
114     */
115    if ((sigaddr = bios_sigsearch(0, "$PnP", 4, 16, 0)) != 0) {
116
117	/* get a virtual pointer to the structure */
118	pt = (struct PnPBIOS_table *)(uintptr_t)BIOS_PADDRTOVADDR(sigaddr);
119	for (cv = (u_int8_t *)pt, ck = 0, i = 0; i < pt->len; i++) {
120	    ck += cv[i];
121	}
122	/* If checksum is OK, enable use of the entrypoint */
123	if (ck == 0) {
124	    PnPBIOStable = pt;
125	    if (bootverbose) {
126		printf("pnpbios: Found PnP BIOS data at %p\n", pt);
127		printf("pnpbios: Entry = %x:%x  Rev = %d.%d\n",
128		       pt->pmentrybase, pt->pmentryoffset, pt->version >> 4, pt->version & 0xf);
129		if ((pt->control & 0x3) == 0x01)
130		    printf("pnpbios: Event flag at %x\n", pt->evflagaddr);
131		if (pt->oemdevid != 0)
132		    printf("pnpbios: OEM ID %x\n", pt->oemdevid);
133
134	    }
135	} else {
136	    printf("pnpbios: Bad PnP BIOS data checksum\n");
137	}
138    }
139
140    if (bootverbose) {
141	    /* look for other know signatures */
142	    printf("Other BIOS signatures found:\n");
143	    printf("ACPI: %08x\n", bios_sigsearch(0, "RSD PTR ", 8, 16, 0));
144    }
145}
146
147/*
148 * bios32_SDlookup
149 *
150 * Query the BIOS32 Service Directory for the service named in (ent),
151 * returns nonzero if the lookup fails.  The caller must fill in
152 * (ent->ident), the remainder are populated on a successful lookup.
153 */
154int
155bios32_SDlookup(struct bios32_SDentry *ent)
156{
157    struct bios_regs args;
158
159    if (bios32_SDCI == 0)
160	return (1);
161
162    args.eax = ent->ident.id;		/* set up arguments */
163    args.ebx = args.ecx = args.edx = 0;
164    bios32(&args, bios32_SDCI, GSEL(GCODE_SEL, SEL_KPL));
165    if ((args.eax & 0xff) == 0) {	/* success? */
166	ent->base = args.ebx;
167	ent->len = args.ecx;
168	ent->entry = args.edx;
169	return (0);			/* all OK */
170    }
171    return (1);				/* failed */
172}
173
174
175/*
176 * bios_sigsearch
177 *
178 * Search some or all of the BIOS region for a signature string.
179 *
180 * (start)	Optional offset returned from this function
181 *		(for searching for multiple matches), or NULL
182 *		to start the search from the base of the BIOS.
183 *		Note that this will be a _physical_ address in
184 *		the range 0xe0000 - 0xfffff.
185 * (sig)	is a pointer to the byte(s) of the signature.
186 * (siglen)	number of bytes in the signature.
187 * (paralen)	signature paragraph (alignment) size.
188 * (sigofs)	offset of the signature within the paragraph.
189 *
190 * Returns the _physical_ address of the found signature, 0 if the
191 * signature was not found.
192 */
193
194u_int32_t
195bios_sigsearch(u_int32_t start, u_char *sig, int siglen, int paralen, int sigofs)
196{
197    u_char	*sp, *end;
198
199    /* compute the starting address */
200    if ((start >= BIOS_START) && (start <= (BIOS_START + BIOS_SIZE))) {
201	sp = (char *)BIOS_PADDRTOVADDR(start);
202    } else if (start == 0) {
203	sp = (char *)BIOS_PADDRTOVADDR(BIOS_START);
204    } else {
205	return 0;				/* bogus start address */
206    }
207
208    /* compute the end address */
209    end = (u_char *)BIOS_PADDRTOVADDR(BIOS_START + BIOS_SIZE);
210
211    /* loop searching */
212    while ((sp + sigofs + siglen) < end) {
213
214	/* compare here */
215	if (!bcmp(sp + sigofs, sig, siglen)) {
216	    /* convert back to physical address */
217	    return((u_int32_t)BIOS_VADDRTOPADDR(sp));
218	}
219	sp += paralen;
220    }
221    return(0);
222}
223
224/*
225 * do not staticize, used by bioscall.s
226 */
227union {
228    struct {
229	u_short	offset;
230	u_short	segment;
231    } vec16;
232    struct {
233	u_int	offset;
234	u_short	segment;
235    } vec32;
236} bioscall_vector;			/* bios jump vector */
237
238void
239set_bios_selectors(struct bios_segments *seg, int flags)
240{
241    struct soft_segment_descriptor ssd = {
242	0,			/* segment base address (overwritten) */
243	0,			/* length (overwritten) */
244	SDT_MEMERA,		/* segment type (overwritten) */
245	0,			/* priority level */
246	1,			/* descriptor present */
247	0, 0,
248	1,			/* descriptor size (overwritten) */
249	0			/* granularity == byte units */
250    };
251    union descriptor *p_gdt;
252
253#ifdef SMP
254    p_gdt = &gdt[cpuid];
255#else
256    p_gdt = gdt;
257#endif
258
259    ssd.ssd_base = seg->code32.base;
260    ssd.ssd_limit = seg->code32.limit;
261    ssdtosd(&ssd, &p_gdt[GBIOSCODE32_SEL].sd);
262
263    ssd.ssd_def32 = 0;
264    if (flags & BIOSCODE_FLAG) {
265	ssd.ssd_base = seg->code16.base;
266	ssd.ssd_limit = seg->code16.limit;
267	ssdtosd(&ssd, &p_gdt[GBIOSCODE16_SEL].sd);
268    }
269
270    ssd.ssd_type = SDT_MEMRWA;
271    if (flags & BIOSDATA_FLAG) {
272	ssd.ssd_base = seg->data.base;
273	ssd.ssd_limit = seg->data.limit;
274	ssdtosd(&ssd, &p_gdt[GBIOSDATA_SEL].sd);
275    }
276
277    if (flags & BIOSUTIL_FLAG) {
278	ssd.ssd_base = seg->util.base;
279	ssd.ssd_limit = seg->util.limit;
280	ssdtosd(&ssd, &p_gdt[GBIOSUTIL_SEL].sd);
281    }
282
283    if (flags & BIOSARGS_FLAG) {
284	ssd.ssd_base = seg->args.base;
285	ssd.ssd_limit = seg->args.limit;
286	ssdtosd(&ssd, &p_gdt[GBIOSARGS_SEL].sd);
287    }
288}
289
290extern int vm86pa;
291extern void bios16_jmp(void);
292
293/*
294 * this routine is really greedy with selectors, and uses 5:
295 *
296 * 32-bit code selector:	to return to kernel
297 * 16-bit code selector:	for running code
298 *        data selector:	for 16-bit data
299 *        util selector:	extra utility selector
300 *        args selector:	to handle pointers
301 *
302 * the util selector is set from the util16 entry in bios16_args, if a
303 * "U" specifier is seen.
304 *
305 * See <machine/pc/bios.h> for description of format specifiers
306 */
307int
308bios16(struct bios_args *args, char *fmt, ...)
309{
310    char	*p, *stack, *stack_top;
311    va_list 	ap;
312    int 	flags = BIOSCODE_FLAG | BIOSDATA_FLAG;
313    u_int 	i, arg_start, arg_end;
314    u_int 	*pte, *ptd;
315
316    arg_start = 0xffffffff;
317    arg_end = 0;
318
319    /*
320     * Some BIOS entrypoints attempt to copy the largest-case
321     * argument frame (in order to generalise handling for
322     * different entry types).  If our argument frame is
323     * smaller than this, the BIOS will reach off the top of
324     * our constructed stack segment.  Pad the top of the stack
325     * with some garbage to avoid this.
326     */
327    stack = (caddr_t)PAGE_SIZE - 32;
328
329    va_start(ap, fmt);
330    for (p = fmt; p && *p; p++) {
331	switch (*p) {
332	case 'p':			/* 32-bit pointer */
333	    i = va_arg(ap, u_int);
334	    arg_start = min(arg_start, i);
335	    arg_end = max(arg_end, i);
336	    flags |= BIOSARGS_FLAG;
337	    stack -= 4;
338	    break;
339
340	case 'i':			/* 32-bit integer */
341	    i = va_arg(ap, u_int);
342	    stack -= 4;
343	    break;
344
345	case 'U':			/* 16-bit selector */
346	    flags |= BIOSUTIL_FLAG;
347	    /* FALLTHROUGH */
348	case 'D':			/* 16-bit selector */
349	case 'C':			/* 16-bit selector */
350	    stack -= 2;
351	    break;
352
353	case 's':			/* 16-bit integer */
354	    i = va_arg(ap, u_short);
355	    stack -= 2;
356	    break;
357
358	default:
359	    return (EINVAL);
360	}
361    }
362
363    if (flags & BIOSARGS_FLAG) {
364	if (arg_end - arg_start > ctob(16))
365	    return (EACCES);
366	args->seg.args.base = arg_start;
367	args->seg.args.limit = 0xffff;
368    }
369
370    args->seg.code32.base = (u_int)&bios16_jmp & PG_FRAME;
371    args->seg.code32.limit = 0xffff;
372
373    ptd = (u_int *)rcr3();
374    if (ptd == IdlePTD) {
375	/*
376	 * no page table, so create one and install it.
377	 */
378	pte = (u_int *)malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
379	ptd = (u_int *)((u_int)ptd + KERNBASE);
380	*ptd = vtophys(pte) | PG_RW | PG_V;
381    } else {
382	/*
383	 * this is a user-level page table
384	 */
385	pte = (u_int *)&PTmap;
386    }
387    /*
388     * install pointer to page 0.  we don't need to flush the tlb,
389     * since there should not be a previous mapping for page 0.
390     */
391    *pte = (vm86pa - PAGE_SIZE) | PG_RW | PG_V;
392
393    stack_top = stack;
394    va_start(ap, fmt);
395    for (p = fmt; p && *p; p++) {
396	switch (*p) {
397	case 'p':			/* 32-bit pointer */
398	    i = va_arg(ap, u_int);
399	    *(u_int *)stack = (i - arg_start) |
400		(GSEL(GBIOSARGS_SEL, SEL_KPL) << 16);
401	    stack += 4;
402	    break;
403
404	case 'i':			/* 32-bit integer */
405	    i = va_arg(ap, u_int);
406	    *(u_int *)stack = i;
407	    stack += 4;
408	    break;
409
410	case 'U':			/* 16-bit selector */
411	    *(u_short *)stack = GSEL(GBIOSUTIL_SEL, SEL_KPL);
412	    stack += 2;
413	    break;
414
415	case 'D':			/* 16-bit selector */
416	    *(u_short *)stack = GSEL(GBIOSDATA_SEL, SEL_KPL);
417	    stack += 2;
418	    break;
419
420	case 'C':			/* 16-bit selector */
421	    *(u_short *)stack = GSEL(GBIOSCODE16_SEL, SEL_KPL);
422	    stack += 2;
423	    break;
424
425	case 's':			/* 16-bit integer */
426	    i = va_arg(ap, u_short);
427	    *(u_short *)stack = i;
428	    stack += 2;
429	    break;
430
431	default:
432	    return (EINVAL);
433	}
434    }
435
436    set_bios_selectors(&args->seg, flags);
437    bioscall_vector.vec16.offset = (u_short)args->entry;
438    bioscall_vector.vec16.segment = GSEL(GBIOSCODE16_SEL, SEL_KPL);
439
440    i = bios16_call(&args->r, stack_top);
441
442    if (pte == (u_int *)&PTmap) {
443	*pte = 0;			/* remove entry */
444    } else {
445	*ptd = 0;			/* remove page table */
446	free(pte, M_TEMP);		/* ... and free it */
447    }
448
449    /*
450     * XXX only needs to be invlpg(0) but that doesn't work on the 386
451     */
452    invltlb();
453
454    return (i);
455}
456
457#ifdef PNPBIOS			/* remove conditional later */
458
459/*
460 * PnP BIOS interface; enumerate devices only known to the system
461 * BIOS and save information about them for later use.
462 */
463
464struct pnp_sysdev
465{
466    u_int16_t	size;
467    u_int8_t	handle;
468    u_int32_t	devid;
469    u_int8_t	type[3];
470    u_int16_t	attrib;
471#define PNPATTR_NODISABLE	(1<<0)	/* can't be disabled */
472#define PNPATTR_NOCONFIG	(1<<1)	/* can't be configured */
473#define PNPATTR_OUTPUT		(1<<2)	/* can be primary output */
474#define PNPATTR_INPUT		(1<<3)	/* can be primary input */
475#define PNPATTR_BOOTABLE	(1<<4)	/* can be booted from */
476#define PNPATTR_DOCK		(1<<5)	/* is a docking station */
477#define PNPATTR_REMOVEABLE	(1<<6)	/* device is removeable */
478#define PNPATTR_CONFIG_STATIC	0x00
479#define PNPATTR_CONFIG_DYNAMIC	0x07
480#define PNPATTR_CONFIG_DYNONLY	0x17
481    /* device-specific data comes here */
482    u_int8_t	devdata[0];
483} __attribute__ ((packed));
484
485/* We have to cluster arguments within a 64k range for the bios16 call */
486struct pnp_sysdevargs
487{
488    u_int16_t	next;
489    struct pnp_sysdev node;
490};
491
492/*
493 * This function is called after the bus has assigned resource
494 * locations for a logical device.
495 */
496static void
497pnpbios_set_config(void *arg, struct isa_config *config, int enable)
498{
499}
500
501/*
502 * Quiz the PnP BIOS, build a list of PNP IDs and resource data.
503 */
504static void
505pnpbios_identify(driver_t *driver, device_t parent)
506{
507    struct PnPBIOS_table	*pt = PnPBIOStable;
508    struct bios_args		args;
509    struct pnp_sysdev		*pd;
510    struct pnp_sysdevargs	*pda;
511    u_int16_t			ndevs, bigdev;
512    int				error, currdev;
513    u_int8_t			*devnodebuf, tag;
514    u_int32_t			*devid, *compid;
515    int				idx, left;
516    device_t			dev;
517
518    /* no PnP BIOS information */
519    if (pt == NULL)
520	return;
521
522    bzero(&args, sizeof(args));
523    args.seg.code16.base = BIOS_PADDRTOVADDR(pt->pmentrybase);
524    args.seg.code16.limit = 0xffff;		/* XXX ? */
525    args.seg.data.base = BIOS_PADDRTOVADDR(pt->pmdataseg);
526    args.seg.data.limit = 0xffff;
527    args.entry = pt->pmentryoffset;
528
529    if ((error = bios16(&args, PNP_COUNT_DEVNODES, &ndevs, &bigdev)) || (args.r.eax & 0xff))
530	printf("pnpbios: error %d/%x getting device count/size limit\n", error, args.r.eax);
531    ndevs &= 0xff;				/* clear high byte garbage */
532    if (bootverbose)
533	printf("pnpbios: %d devices, largest %d bytes\n", ndevs, bigdev);
534
535    devnodebuf = malloc(bigdev + (sizeof(struct pnp_sysdevargs) - sizeof(struct pnp_sysdev)),
536			M_DEVBUF, M_NOWAIT);
537    pda = (struct pnp_sysdevargs *)devnodebuf;
538    pd = &pda->node;
539
540    for (currdev = 0, left = ndevs; (currdev != 0xff) && (left > 0); left--) {
541
542	bzero(pd, bigdev);
543	pda->next = currdev;
544	/* get current configuration */
545	if ((error = bios16(&args, PNP_GET_DEVNODE, &pda->next, &pda->node, (u_int16_t)1))) {
546	    printf("pnpbios: error %d making BIOS16 call\n", error);
547	    break;
548	}
549	if ((error = (args.r.eax & 0xff))) {
550	    if (bootverbose)
551		printf("pnpbios: %s 0x%x fetching node %d\n", error & 0x80 ? "error" : "warning", error, currdev);
552	    if (error & 0x80)
553		break;
554	}
555	currdev = pda->next;
556	if (pd->size < sizeof(struct pnp_sysdev)) {
557	    printf("pnpbios: bogus system node data, aborting scan\n");
558	    break;
559	}
560
561	/* Add the device and parse its resources */
562	dev = BUS_ADD_CHILD(parent, ISA_ORDER_PNP, NULL, -1);
563	isa_set_vendorid(dev, pd->devid);
564	isa_set_logicalid(dev, pd->devid);
565	ISA_SET_CONFIG_CALLBACK(parent, dev, pnpbios_set_config, 0);
566	pnp_parse_resources(dev, &pd->devdata[0],
567			    pd->size - sizeof(struct pnp_sysdev));
568	if (!device_get_desc(dev))
569	    device_set_desc_copy(dev, pnp_eisaformat(pd->devid));
570
571	/* Find device IDs */
572	devid = &pd->devid;
573	compid = NULL;
574
575	/* look for a compatible device ID too */
576	left = pd->size - sizeof(struct pnp_sysdev);
577	idx = 0;
578	while (idx < left) {
579	    tag = pd->devdata[idx++];
580	    if (PNP_RES_TYPE(tag) == 0) {
581		/* Small resource */
582		switch (PNP_SRES_NUM(tag)) {
583		case PNP_TAG_COMPAT_DEVICE:
584		    compid = (u_int32_t *)(pd->devdata + idx);
585		    if (bootverbose)
586			printf("pnpbios: node %d compat ID 0x%08x\n", pd->handle, *compid);
587		    /* FALLTHROUGH */
588		case PNP_TAG_END:
589		    idx = left;
590		    break;
591		default:
592		    idx += PNP_SRES_LEN(tag);
593		    break;
594		}
595	    } else
596		/* Large resource, skip it */
597		idx += *(u_int16_t *)(pd->devdata + idx) + 2;
598	}
599	if (bootverbose) {
600	    printf("pnpbios: handle %d device ID %s (%08x)",
601		   pd->handle, pnp_eisaformat(*devid), *devid);
602	    if (compid != NULL)
603		printf(" compat ID %s (%08x)",
604		       pnp_eisaformat(*compid), *compid);
605	    printf("\n");
606	}
607    }
608}
609
610static device_method_t pnpbios_methods[] = {
611	/* Device interface */
612	DEVMETHOD(device_identify,	pnpbios_identify),
613
614	{ 0, 0 }
615};
616
617static driver_t pnpbios_driver = {
618	"pnpbios",
619	pnpbios_methods,
620	1,			/* no softc */
621};
622
623static devclass_t pnpbios_devclass;
624
625DRIVER_MODULE(pnpbios, isa, pnpbios_driver, pnpbios_devclass, 0, 0);
626
627#endif /* PNPBIOS */
628