bios.c revision 52121 
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 52121 1999-10-11 14:50:03Z peter $
28 */
29
30/*
31 * Code for dealing with the BIOS in x86 PC systems.
32 */
33
34#include <sys/param.h>
35#include <sys/systm.h>
36#include <sys/kernel.h>
37#include <sys/malloc.h>
38#include <vm/vm.h>
39#include <vm/pmap.h>
40#include <machine/md_var.h>
41#include <machine/segments.h>
42#include <machine/stdarg.h>
43#include <machine/vmparam.h>
44#include <machine/pc/bios.h>
45#include <isa/pnpreg.h>
46
47#define BIOS_START	0xe0000
48#define BIOS_SIZE	0x20000
49
50/* exported lookup results */
51struct bios32_SDentry		PCIbios = {entry : 0};
52struct PnPBIOS_table		*PnPBIOStable = 0;
53
54static u_int			bios32_SDCI = 0;
55
56/* start fairly early */
57static void			bios32_init(void *junk);
58SYSINIT(bios32, SI_SUB_CPU, SI_ORDER_ANY, bios32_init, NULL);
59
60static void	pnpbios_scan(void);
61static char 	*pnp_eisaformat(u_int8_t *data);
62
63
64/*
65 * bios32_init
66 *
67 * Locate various bios32 entities.
68 */
69static void
70bios32_init(void *junk)
71{
72    u_long			sigaddr;
73    struct bios32_SDheader	*sdh;
74    struct PnPBIOS_table	*pt;
75    u_int8_t			ck, *cv;
76    int				i;
77
78    /*
79     * BIOS32 Service Directory
80     */
81
82    /* look for the signature */
83    if ((sigaddr = bios_sigsearch(0, "_32_", 4, 16, 0)) != 0) {
84
85	/* get a virtual pointer to the structure */
86	sdh = (struct bios32_SDheader *)(uintptr_t)BIOS_PADDRTOVADDR(sigaddr);
87	for (cv = (u_int8_t *)sdh, ck = 0, i = 0; i < (sdh->len * 16); i++) {
88	    ck += cv[i];
89	}
90	/* If checksum is OK, enable use of the entrypoint */
91	if ((ck == 0) && (sdh->entry < (BIOS_START + BIOS_SIZE))) {
92	    bios32_SDCI = BIOS_PADDRTOVADDR(sdh->entry);
93	    if (bootverbose) {
94		printf("bios32: Found BIOS32 Service Directory header at %p\n", sdh);
95		printf("bios32: Entry = 0x%x (%x)  Rev = %d  Len = %d\n",
96		       sdh->entry, bios32_SDCI, sdh->revision, sdh->len);
97	    }
98	    /* See if there's a PCI BIOS entrypoint here */
99	    PCIbios.ident.id = 0x49435024;	/* PCI systems should have this */
100	    if (!bios32_SDlookup(&PCIbios) && bootverbose)
101		printf("pcibios: PCI BIOS entry at 0x%x\n", PCIbios.entry);
102	} else {
103	    printf("bios32: Bad BIOS32 Service Directory\n");
104	}
105    }
106
107    /*
108     * PnP BIOS
109     */
110    if ((sigaddr = bios_sigsearch(0, "$PnP", 4, 16, 0)) != 0) {
111
112	/* get a virtual pointer to the structure */
113	pt = (struct PnPBIOS_table *)(uintptr_t)BIOS_PADDRTOVADDR(sigaddr);
114	for (cv = (u_int8_t *)pt, ck = 0, i = 0; i < pt->len; i++) {
115	    ck += cv[i];
116	}
117	/* If checksum is OK, enable use of the entrypoint */
118	if (ck == 0) {
119	    PnPBIOStable = pt;
120	    if (bootverbose) {
121		printf("pnpbios: Found PnP BIOS data at %p\n", pt);
122		printf("pnpbios: Entry = %x:%x  Rev = %d.%d\n",
123		       pt->pmentrybase, pt->pmentryoffset, pt->version >> 4, pt->version & 0xf);
124		if ((pt->control & 0x3) == 0x01)
125		    printf("pnpbios: Event flag at %x\n", pt->evflagaddr);
126		if (pt->oemdevid != 0)
127		    printf("pnpbios: OEM ID %x\n", pt->oemdevid);
128
129	    }
130	    pnpbios_scan();
131	} else {
132	    printf("pnpbios: Bad PnP BIOS data checksum\n");
133	}
134    }
135
136    if (bootverbose) {
137	    /* look for other know signatures */
138	    printf("Other BIOS signatures found:\n");
139	    printf("ACPI: %08x\n", bios_sigsearch(0, "RSD PTR ", 8, 16, 0));
140    }
141}
142
143/*
144 * bios32_SDlookup
145 *
146 * Query the BIOS32 Service Directory for the service named in (ent),
147 * returns nonzero if the lookup fails.  The caller must fill in
148 * (ent->ident), the remainder are populated on a successful lookup.
149 */
150int
151bios32_SDlookup(struct bios32_SDentry *ent)
152{
153    struct bios_regs args;
154
155    if (bios32_SDCI == 0)
156	return (1);
157
158    args.eax = ent->ident.id;		/* set up arguments */
159    args.ebx = args.ecx = args.edx = 0;
160    bios32(&args, bios32_SDCI, GSEL(GCODE_SEL, SEL_KPL));
161    if ((args.eax & 0xff) == 0) {	/* success? */
162	ent->base = args.ebx;
163	ent->len = args.ecx;
164	ent->entry = args.edx;
165	return (0);			/* all OK */
166    }
167    return (1);				/* failed */
168}
169
170
171/*
172 * bios_sigsearch
173 *
174 * Search some or all of the BIOS region for a signature string.
175 *
176 * (start)	Optional offset returned from this function
177 *		(for searching for multiple matches), or NULL
178 *		to start the search from the base of the BIOS.
179 *		Note that this will be a _physical_ address in
180 *		the range 0xe0000 - 0xfffff.
181 * (sig)	is a pointer to the byte(s) of the signature.
182 * (siglen)	number of bytes in the signature.
183 * (paralen)	signature paragraph (alignment) size.
184 * (sigofs)	offset of the signature within the paragraph.
185 *
186 * Returns the _physical_ address of the found signature, 0 if the
187 * signature was not found.
188 */
189
190u_int32_t
191bios_sigsearch(u_int32_t start, u_char *sig, int siglen, int paralen, int sigofs)
192{
193    u_char	*sp, *end;
194
195    /* compute the starting address */
196    if ((start >= BIOS_START) && (start <= (BIOS_START + BIOS_SIZE))) {
197	sp = (char *)BIOS_PADDRTOVADDR(start);
198    } else if (start == 0) {
199	sp = (char *)BIOS_PADDRTOVADDR(BIOS_START);
200    } else {
201	return 0;				/* bogus start address */
202    }
203
204    /* compute the end address */
205    end = (u_char *)BIOS_PADDRTOVADDR(BIOS_START + BIOS_SIZE);
206
207    /* loop searching */
208    while ((sp + sigofs + siglen) < end) {
209
210	/* compare here */
211	if (!bcmp(sp + sigofs, sig, siglen)) {
212	    /* convert back to physical address */
213	    return((u_int32_t)BIOS_VADDRTOPADDR(sp));
214	}
215	sp += paralen;
216    }
217    return(0);
218}
219
220/*
221 * do not staticize, used by bioscall.s
222 */
223union {
224    struct {
225	u_short	offset;
226	u_short	segment;
227    } vec16;
228    struct {
229	u_int	offset;
230	u_short	segment;
231    } vec32;
232} bioscall_vector;			/* bios jump vector */
233
234void
235set_bios_selectors(struct bios_segments *seg, int flags)
236{
237    struct soft_segment_descriptor ssd = {
238	0,			/* segment base address (overwritten) */
239	0,			/* length (overwritten) */
240	SDT_MEMERA,		/* segment type (overwritten) */
241	0,			/* priority level */
242	1,			/* descriptor present */
243	0, 0,
244	1,			/* descriptor size (overwritten) */
245	0			/* granularity == byte units */
246    };
247    union descriptor *p_gdt;
248
249#ifdef SMP
250    p_gdt = &gdt[cpuid];
251#else
252    p_gdt = gdt;
253#endif
254
255    ssd.ssd_base = seg->code32.base;
256    ssd.ssd_limit = seg->code32.limit;
257    ssdtosd(&ssd, &p_gdt[GBIOSCODE32_SEL].sd);
258
259    ssd.ssd_def32 = 0;
260    if (flags & BIOSCODE_FLAG) {
261	ssd.ssd_base = seg->code16.base;
262	ssd.ssd_limit = seg->code16.limit;
263	ssdtosd(&ssd, &p_gdt[GBIOSCODE16_SEL].sd);
264    }
265
266    ssd.ssd_type = SDT_MEMRWA;
267    if (flags & BIOSDATA_FLAG) {
268	ssd.ssd_base = seg->data.base;
269	ssd.ssd_limit = seg->data.limit;
270	ssdtosd(&ssd, &p_gdt[GBIOSDATA_SEL].sd);
271    }
272
273    if (flags & BIOSUTIL_FLAG) {
274	ssd.ssd_base = seg->util.base;
275	ssd.ssd_limit = seg->util.limit;
276	ssdtosd(&ssd, &p_gdt[GBIOSUTIL_SEL].sd);
277    }
278
279    if (flags & BIOSARGS_FLAG) {
280	ssd.ssd_base = seg->args.base;
281	ssd.ssd_limit = seg->args.limit;
282	ssdtosd(&ssd, &p_gdt[GBIOSARGS_SEL].sd);
283    }
284}
285
286extern int vm86pa;
287extern void bios16_jmp(void);
288
289/*
290 * this routine is really greedy with selectors, and uses 5:
291 *
292 * 32-bit code selector:	to return to kernel
293 * 16-bit code selector:	for running code
294 *        data selector:	for 16-bit data
295 *        util selector:	extra utility selector
296 *        args selector:	to handle pointers
297 *
298 * the util selector is set from the util16 entry in bios16_args, if a
299 * "U" specifier is seen.
300 *
301 * See <machine/pc/bios.h> for description of format specifiers
302 */
303int
304bios16(struct bios_args *args, char *fmt, ...)
305{
306    char	*p, *stack, *stack_top;
307    va_list 	ap;
308    int 	flags = BIOSCODE_FLAG | BIOSDATA_FLAG;
309    u_int 	i, arg_start, arg_end;
310    u_int 	*pte, *ptd;
311
312    arg_start = 0xffffffff;
313    arg_end = 0;
314
315    /*
316     * Some BIOS entrypoints attempt to copy the largest-case
317     * argument frame (in order to generalise handling for
318     * different entry types).  If our argument frame is
319     * smaller than this, the BIOS will reach off the top of
320     * our constructed stack segment.  Pad the top of the stack
321     * with some garbage to avoid this.
322     */
323    stack = (caddr_t)PAGE_SIZE - 32;
324
325    va_start(ap, fmt);
326    for (p = fmt; p && *p; p++) {
327	switch (*p) {
328	case 'p':			/* 32-bit pointer */
329	    i = va_arg(ap, u_int);
330	    arg_start = min(arg_start, i);
331	    arg_end = max(arg_end, i);
332	    flags |= BIOSARGS_FLAG;
333	    stack -= 4;
334	    break;
335
336	case 'i':			/* 32-bit integer */
337	    i = va_arg(ap, u_int);
338	    stack -= 4;
339	    break;
340
341	case 'U':			/* 16-bit selector */
342	    flags |= BIOSUTIL_FLAG;
343	    /* FALLTHROUGH */
344	case 'D':			/* 16-bit selector */
345	case 'C':			/* 16-bit selector */
346	    stack -= 2;
347	    break;
348
349	case 's':			/* 16-bit integer */
350	    i = va_arg(ap, u_short);
351	    stack -= 2;
352	    break;
353
354	default:
355	    return (EINVAL);
356	}
357    }
358
359    if (flags & BIOSARGS_FLAG) {
360	if (arg_end - arg_start > ctob(16))
361	    return (EACCES);
362	args->seg.args.base = arg_start;
363	args->seg.args.limit = 0xffff;
364    }
365
366    args->seg.code32.base = (u_int)&bios16_jmp & PG_FRAME;
367    args->seg.code32.limit = 0xffff;
368
369    ptd = (u_int *)rcr3();
370    if (ptd == IdlePTD) {
371	/*
372	 * no page table, so create one and install it.
373	 */
374	pte = (u_int *)malloc(PAGE_SIZE, M_TEMP, M_WAITOK);
375	ptd = (u_int *)((u_int)ptd + KERNBASE);
376	*ptd = vtophys(pte) | PG_RW | PG_V;
377    } else {
378	/*
379	 * this is a user-level page table
380	 */
381	pte = (u_int *)&PTmap;
382    }
383    /*
384     * install pointer to page 0.  we don't need to flush the tlb,
385     * since there should not be a previous mapping for page 0.
386     */
387    *pte = (vm86pa - PAGE_SIZE) | PG_RW | PG_V;
388
389    stack_top = stack;
390    va_start(ap, fmt);
391    for (p = fmt; p && *p; p++) {
392	switch (*p) {
393	case 'p':			/* 32-bit pointer */
394	    i = va_arg(ap, u_int);
395	    *(u_int *)stack = (i - arg_start) |
396		(GSEL(GBIOSARGS_SEL, SEL_KPL) << 16);
397	    stack += 4;
398	    break;
399
400	case 'i':			/* 32-bit integer */
401	    i = va_arg(ap, u_int);
402	    *(u_int *)stack = i;
403	    stack += 4;
404	    break;
405
406	case 'U':			/* 16-bit selector */
407	    *(u_short *)stack = GSEL(GBIOSUTIL_SEL, SEL_KPL);
408	    stack += 2;
409	    break;
410
411	case 'D':			/* 16-bit selector */
412	    *(u_short *)stack = GSEL(GBIOSDATA_SEL, SEL_KPL);
413	    stack += 2;
414	    break;
415
416	case 'C':			/* 16-bit selector */
417	    *(u_short *)stack = GSEL(GBIOSCODE16_SEL, SEL_KPL);
418	    stack += 2;
419	    break;
420
421	case 's':			/* 16-bit integer */
422	    i = va_arg(ap, u_short);
423	    *(u_short *)stack = i;
424	    stack += 2;
425	    break;
426
427	default:
428	    return (EINVAL);
429	}
430    }
431
432    set_bios_selectors(&args->seg, flags);
433    bioscall_vector.vec16.offset = (u_short)args->entry;
434    bioscall_vector.vec16.segment = GSEL(GBIOSCODE16_SEL, SEL_KPL);
435
436    i = bios16_call(&args->r, stack_top);
437
438    if (pte == (u_int *)&PTmap) {
439	*pte = 0;			/* remove entry */
440    } else {
441	*ptd = 0;			/* remove page table */
442	free(pte, M_TEMP);		/* ... and free it */
443    }
444
445    /*
446     * XXX only needs to be invlpg(0) but that doesn't work on the 386
447     */
448    invltlb();
449
450    return (i);
451}
452
453/*
454 * PnP BIOS interface; enumerate devices only known to the system
455 * BIOS and save information about them for later use.
456 */
457
458struct pnp_sysdev
459{
460    u_int16_t	size;
461    u_int8_t	handle;
462    u_int32_t	devid;
463    u_int8_t	type[3];
464    u_int16_t	attrib;
465#define PNPATTR_NODISABLE	(1<<0)	/* can't be disabled */
466#define PNPATTR_NOCONFIG	(1<<1)	/* can't be configured */
467#define PNPATTR_OUTPUT		(1<<2)	/* can be primary output */
468#define PNPATTR_INPUT		(1<<3)	/* can be primary input */
469#define PNPATTR_BOOTABLE	(1<<4)	/* can be booted from */
470#define PNPATTR_DOCK		(1<<5)	/* is a docking station */
471#define PNPATTR_REMOVEABLE	(1<<6)	/* device is removeable */
472#define PNPATTR_CONFIG_STATIC	0x00
473#define PNPATTR_CONFIG_DYNAMIC	0x07
474#define PNPATTR_CONFIG_DYNONLY	0x17
475    /* device-specific data comes here */
476    u_int8_t	devdata[0];
477} __attribute__ ((packed));
478
479/* We have to cluster arguments within a 64k range for the bios16 call */
480struct pnp_sysdevargs
481{
482    u_int16_t	next;
483    struct pnp_sysdev node;
484};
485
486/*
487 * Quiz the PnP BIOS, build a list of PNP IDs and resource data.
488 */
489static void
490pnpbios_scan(void)
491{
492    struct PnPBIOS_table	*pt = PnPBIOStable;
493    struct bios_args		args;
494    struct pnp_sysdev		*pd;
495    struct pnp_sysdevargs	*pda;
496    u_int16_t			ndevs, bigdev;
497    int				error, currdev;
498    u_int8_t			*devnodebuf, tag;
499    u_int32_t			*devid, *compid;
500    int				idx, left;
501
502    /* no PnP BIOS information */
503    if (pt == NULL)
504	return;
505
506    bzero(&args, sizeof(args));
507    args.seg.code16.base = BIOS_PADDRTOVADDR(pt->pmentrybase);
508    args.seg.code16.limit = 0xffff;		/* XXX ? */
509    args.seg.data.base = BIOS_PADDRTOVADDR(pt->pmdataseg);
510    args.seg.data.limit = 0xffff;
511    args.entry = pt->pmentryoffset;
512
513    if ((error = bios16(&args, PNP_COUNT_DEVNODES, &ndevs, &bigdev)) || (args.r.eax & 0xff))
514	printf("pnpbios: error %d/%x getting device count/size limit\n", error, args.r.eax);
515    ndevs &= 0xff;				/* clear high byte garbage */
516    if (bootverbose)
517	printf("pnpbios: %d devices, largest %d bytes\n", ndevs, bigdev);
518
519    devnodebuf = malloc(bigdev + (sizeof(struct pnp_sysdevargs) - sizeof(struct pnp_sysdev)),
520			M_DEVBUF, M_NOWAIT);
521    pda = (struct pnp_sysdevargs *)devnodebuf;
522    pd = &pda->node;
523
524    for (currdev = 0, left = ndevs; (currdev != 0xff) && (left > 0); left--) {
525
526	bzero(pd, bigdev);
527	pda->next = currdev;
528	/* get current configuration */
529	if ((error = bios16(&args, PNP_GET_DEVNODE, &pda->next, &pda->node, (u_int16_t)1))) {
530	    printf("pnpbios: error %d making BIOS16 call\n", error);
531	    break;
532	}
533	if ((error = (args.r.eax & 0xff))) {
534	    if (bootverbose)
535		printf("pnpbios: %s 0x%x fetching node %d\n", error & 0x80 ? "error" : "warning", error, currdev);
536	    if (error & 0x80)
537		break;
538	}
539	currdev = pda->next;
540	if (pd->size < sizeof(struct pnp_sysdev)) {
541	    printf("pnpbios: bogus system node data, aborting scan\n");
542	    break;
543	}
544
545	/* Find device IDs */
546	devid = &pd->devid;
547	compid = NULL;
548
549	/* look for a compatible device ID too */
550	left = pd->size - sizeof(struct pnp_sysdev);
551	idx = 0;
552	while (idx < left) {
553	    tag = pd->devdata[idx++];
554	    if (PNP_RES_TYPE(tag) == 0) {
555		/* Small resource */
556		switch (PNP_SRES_NUM(tag)) {
557		case PNP_TAG_COMPAT_DEVICE:
558		    compid = (u_int32_t *)(pd->devdata + idx);
559		    if (bootverbose)
560			printf("pnpbios: node %d compat ID 0x%08x\n", pd->handle, *compid);
561		    /* FALLTHROUGH */
562		case PNP_TAG_END:
563		    idx = left;
564		    break;
565		default:
566		    idx += PNP_SRES_LEN(tag);
567		    break;
568		}
569	    } else
570		/* Large resource, skip it */
571		idx += *(u_int16_t *)(pd->devdata + idx) + 2;
572	}
573	if (bootverbose) {
574	    printf("pnpbios: handle %d device ID %s (%08x)",
575		   pd->handle, pnp_eisaformat((u_int8_t *)devid), *devid);
576	    if (compid != NULL)
577		printf(" compat ID %s (%08x)",
578		       pnp_eisaformat((u_int8_t *)compid), *compid);
579	    printf("\n");
580	}
581    }
582}
583
584/* XXX should be somewhere else */
585static char *
586pnp_eisaformat(u_int8_t *data)
587{
588    static char idbuf[8];
589    const char  hextoascii[] = "0123456789abcdef";
590
591    idbuf[0] = '@' + ((data[0] & 0x7c) >> 2);
592    idbuf[1] = '@' + (((data[0] & 0x3) << 3) + ((data[1] & 0xe0) >> 5));
593    idbuf[2] = '@' + (data[1] & 0x1f);
594    idbuf[3] = hextoascii[(data[2] >> 4)];
595    idbuf[4] = hextoascii[(data[2] & 0xf)];
596    idbuf[5] = hextoascii[(data[3] >> 4)];
597    idbuf[6] = hextoascii[(data[3] & 0xf)];
598    idbuf[7] = 0;
599    return(idbuf);
600}
601