boot2.c revision 239063 
1/*-
2 * Copyright (c) 2008-2009 TAKAHASHI Yoshihiro
3 * Copyright (c) 1998 Robert Nordier
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms are freely
7 * permitted provided that the above copyright notice and this
8 * paragraph and the following disclaimer are duplicated in all
9 * such forms.
10 *
11 * This software is provided "AS IS" and without any express or
12 * implied warranties, including, without limitation, the implied
13 * warranties of merchantability and fitness for a particular
14 * purpose.
15 */
16
17#include <sys/cdefs.h>
18__FBSDID("$FreeBSD: head/sys/boot/pc98/boot2/boot2.c 239063 2012-08-05 14:05:11Z nyan $");
19
20#include <sys/param.h>
21#include <sys/disklabel.h>
22#include <sys/diskpc98.h>
23#include <sys/dirent.h>
24#include <sys/reboot.h>
25
26#include <machine/bootinfo.h>
27#include <machine/cpufunc.h>
28#include <machine/elf.h>
29
30#include <stdarg.h>
31
32#include <a.out.h>
33
34#include <btxv86.h>
35
36#include "boot2.h"
37#include "lib.h"
38
39#define IO_KEYBOARD	1
40#define IO_SERIAL	2
41
42#define SECOND		1	/* Circa that many ticks in a second. */
43
44#define RBX_ASKNAME	0x0	/* -a */
45#define RBX_SINGLE	0x1	/* -s */
46/* 0x2 is reserved for log2(RB_NOSYNC). */
47/* 0x3 is reserved for log2(RB_HALT). */
48/* 0x4 is reserved for log2(RB_INITNAME). */
49#define RBX_DFLTROOT	0x5	/* -r */
50#define RBX_KDB 	0x6	/* -d */
51/* 0x7 is reserved for log2(RB_RDONLY). */
52/* 0x8 is reserved for log2(RB_DUMP). */
53/* 0x9 is reserved for log2(RB_MINIROOT). */
54#define RBX_CONFIG	0xa	/* -c */
55#define RBX_VERBOSE	0xb	/* -v */
56#define RBX_SERIAL	0xc	/* -h */
57#define RBX_CDROM	0xd	/* -C */
58/* 0xe is reserved for log2(RB_POWEROFF). */
59#define RBX_GDB 	0xf	/* -g */
60#define RBX_MUTE	0x10	/* -m */
61/* 0x11 is reserved for log2(RB_SELFTEST). */
62/* 0x12 is reserved for boot programs. */
63/* 0x13 is reserved for boot programs. */
64#define RBX_PAUSE	0x14	/* -p */
65#define RBX_QUIET	0x15	/* -q */
66#define RBX_NOINTR	0x1c	/* -n */
67/* 0x1d is reserved for log2(RB_MULTIPLE) and is just misnamed here. */
68#define RBX_DUAL	0x1d	/* -D */
69/* 0x1f is reserved for log2(RB_BOOTINFO). */
70
71/* pass: -a, -s, -r, -d, -c, -v, -h, -C, -g, -m, -p, -D */
72#define RBX_MASK	(OPT_SET(RBX_ASKNAME) | OPT_SET(RBX_SINGLE) | \
73			OPT_SET(RBX_DFLTROOT) | OPT_SET(RBX_KDB ) | \
74			OPT_SET(RBX_CONFIG) | OPT_SET(RBX_VERBOSE) | \
75			OPT_SET(RBX_SERIAL) | OPT_SET(RBX_CDROM) | \
76			OPT_SET(RBX_GDB ) | OPT_SET(RBX_MUTE) | \
77			OPT_SET(RBX_PAUSE) | OPT_SET(RBX_DUAL))
78
79#define PATH_DOTCONFIG	"/boot.config"
80#define PATH_CONFIG	"/boot/config"
81#define PATH_BOOT3	"/boot/loader"
82#define PATH_KERNEL	"/boot/kernel/kernel"
83
84#define ARGS		0x900
85#define NOPT		14
86#define NDEV		3
87
88#define DRV_DISK	0xf0
89#define DRV_UNIT	0x0f
90
91#define TYPE_AD		0
92#define TYPE_DA		1
93#define TYPE_FD		2
94
95#define OPT_SET(opt)	(1 << (opt))
96#define OPT_CHECK(opt)	((opts) & OPT_SET(opt))
97
98extern uint32_t _end;
99
100static const char optstr[NOPT] = "DhaCcdgmnpqrsv"; /* Also 'P', 'S' */
101static const unsigned char flags[NOPT] = {
102    RBX_DUAL,
103    RBX_SERIAL,
104    RBX_ASKNAME,
105    RBX_CDROM,
106    RBX_CONFIG,
107    RBX_KDB,
108    RBX_GDB,
109    RBX_MUTE,
110    RBX_NOINTR,
111    RBX_PAUSE,
112    RBX_QUIET,
113    RBX_DFLTROOT,
114    RBX_SINGLE,
115    RBX_VERBOSE
116};
117
118static const char *const dev_nm[NDEV] = {"ad", "da", "fd"};
119static const unsigned char dev_maj[NDEV] = {30, 4, 2};
120static const unsigned char dev_daua[NDEV] = {0x80, 0xa0, 0x90};
121
122static struct dsk {
123    unsigned daua;
124    unsigned type;
125    unsigned disk;
126    unsigned unit;
127    unsigned head;
128    unsigned sec;
129    uint8_t slice;
130    uint8_t part;
131    unsigned start;
132} dsk;
133static char cmd[512], cmddup[512], knamebuf[1024];
134static const char *kname;
135static uint32_t opts;
136static int comspeed = SIOSPD;
137static struct bootinfo bootinfo;
138static uint8_t ioctrl = IO_KEYBOARD;
139
140void exit(int);
141static void load(void);
142static int parse(void);
143static int dskread(void *, unsigned, unsigned);
144static void printf(const char *,...);
145static void putchar(int);
146static int drvread(void *, unsigned);
147static int keyhit(unsigned);
148static int xputc(int);
149static int xgetc(int);
150static inline int getc(int);
151
152static void memcpy(void *, const void *, int);
153static void
154memcpy(void *dst, const void *src, int len)
155{
156    const char *s = src;
157    char *d = dst;
158
159    while (len--)
160        *d++ = *s++;
161}
162
163static inline int
164strcmp(const char *s1, const char *s2)
165{
166    for (; *s1 == *s2 && *s1; s1++, s2++);
167    return (unsigned char)*s1 - (unsigned char)*s2;
168}
169
170#define	UFS_SMALL_CGBASE
171#include "ufsread.c"
172
173static inline int
174xfsread(ufs_ino_t inode, void *buf, size_t nbyte)
175{
176    if ((size_t)fsread(inode, buf, nbyte) != nbyte) {
177	printf("Invalid %s\n", "format");
178	return -1;
179    }
180    return 0;
181}
182
183static inline void
184getstr(void)
185{
186    char *s;
187    int c;
188
189    s = cmd;
190    for (;;) {
191	switch (c = xgetc(0)) {
192	case 0:
193	    break;
194	case '\177':
195	case '\b':
196	    if (s > cmd) {
197		s--;
198		printf("\b \b");
199	    }
200	    break;
201	case '\n':
202	case '\r':
203	    *s = 0;
204	    return;
205	default:
206	    if (s - cmd < sizeof(cmd) - 1)
207		*s++ = c;
208	    putchar(c);
209	}
210    }
211}
212
213static inline void
214putc(int c)
215{
216
217    v86.ctl = V86_ADDR | V86_CALLF | V86_FLAGS;
218    v86.addr = PUTCORG;		/* call to putc in boot1 */
219    v86.eax = c;
220    v86int();
221    v86.ctl = V86_FLAGS;
222}
223
224static inline int
225is_scsi_hd(void)
226{
227
228    if ((*(u_char *)PTOV(0x482) >> dsk.unit) & 0x01)
229	return 1;
230
231    return 0;
232}
233
234static inline void
235fix_sector_size(void)
236{
237    u_char *p;
238
239    p = (u_char *)PTOV(0x460 + dsk.unit * 4);	/* SCSI equipment parameter */
240
241    if ((p[0] & 0x1f) == 7) {		/* SCSI MO */
242	if (!(p[3] & 0x30)) {		/* 256B / sector */
243	    p[3] |= 0x10;		/* forced set 512B / sector */
244	    p[3 + 0xa1000] |= 0x10;
245	}
246    }
247}
248
249static inline uint32_t
250get_diskinfo(void)
251{
252
253    if (dsk.disk == 0x30) {				/* 1440KB FD */
254	/* 80 cylinders, 2 heads, 18 sectors */
255	return (80 << 16) | (2 << 8) | 18;
256    } else if (dsk.disk == 0x90) {			/* 1200KB FD */
257	/* 80 cylinders, 2 heads, 15 sectors */
258	return (80 << 16) | (2 << 8) | 15;
259    } else if (dsk.disk == 0x80 || is_scsi_hd()) {	/* IDE or SCSI HDD */
260	v86.addr = 0x1b;
261	v86.eax = 0x8400 | dsk.daua;
262	v86int();
263	return (v86.ecx << 16) | v86.edx;
264    }
265
266    /* SCSI MO or CD */
267    fix_sector_size();	/* SCSI MO */
268
269    /* other SCSI devices */
270    return (65535 << 16) | (8 << 8) | 32;
271}
272
273static void
274set_dsk(void)
275{
276    uint32_t di;
277
278    di = get_diskinfo();
279
280    dsk.head = (di >> 8) & 0xff;
281    dsk.sec = di & 0xff;
282    dsk.start = 0;
283}
284
285#ifdef GET_BIOSGEOM
286static uint32_t
287bd_getbigeom(int bunit)
288{
289    int hds = 0;
290    int unit = 0x80;		/* IDE HDD */
291    u_int addr = 0x55d;
292
293    while (unit < 0xa7) {
294	if (*(u_char *)PTOV(addr) & (1 << (unit & 0x0f)))
295	    if (hds++ == bunit)
296		break;
297
298	if (unit >= 0xA0) {
299	    int media = ((unsigned *)PTOV(0x460))[unit & 0x0F] & 0x1F;
300
301	    if (media == 7 && hds++ == bunit)	/* SCSI MO */
302		return(0xFFFE0820); /* C:65535 H:8 S:32 */
303	}
304	if (++unit == 0x84) {
305	    unit = 0xA0;	/* SCSI HDD */
306	    addr = 0x482;
307	}
308    }
309    if (unit == 0xa7)
310	return 0x4F020F;	/* 1200KB FD C:80 H:2 S:15 */
311    v86.addr = 0x1b;
312    v86.eax = 0x8400 | unit;
313    v86int();
314    if (v86.efl & 0x1)
315	return 0x4F020F;	/* 1200KB FD C:80 H:2 S:15 */
316    return ((v86.ecx & 0xffff) << 16) | (v86.edx & 0xffff);
317}
318#endif
319
320static int
321check_slice(void)
322{
323    struct pc98_partition *dp;
324    char *sec;
325    unsigned i, cyl;
326
327    sec = dmadat->secbuf;
328    cyl = *(uint16_t *)PTOV(ARGS);
329    set_dsk();
330
331    if (dsk.type == TYPE_FD)
332	return (WHOLE_DISK_SLICE);
333    if (drvread(sec, DOSBBSECTOR + 1))
334	return (WHOLE_DISK_SLICE);	/* Read error */
335    dp = (void *)(sec + DOSPARTOFF);
336    for (i = 0; i < NDOSPART; i++) {
337	if (dp[i].dp_mid == DOSMID_386BSD) {
338	    if (dp[i].dp_scyl <= cyl && cyl <= dp[i].dp_ecyl)
339		return (BASE_SLICE + i);
340	}
341    }
342
343    return (WHOLE_DISK_SLICE);
344}
345
346int
347main(void)
348{
349#ifdef GET_BIOSGEOM
350    int i;
351#endif
352    uint8_t autoboot;
353    ufs_ino_t ino;
354    size_t nbyte;
355
356    dmadat = (void *)(roundup2(__base + (int32_t)&_end, 0x10000) - __base);
357    v86.ctl = V86_FLAGS;
358    v86.efl = PSL_RESERVED_DEFAULT | PSL_I;
359    dsk.daua = *(uint8_t *)PTOV(0x584);
360    dsk.disk = dsk.daua & DRV_DISK;
361    dsk.unit = dsk.daua & DRV_UNIT;
362    if (dsk.disk == 0x80)
363        dsk.type = TYPE_AD;
364    else if (dsk.disk == 0xa0)
365        dsk.type = TYPE_DA;
366    else /* if (dsk.disk == 0x30 || dsk.disk == 0x90) */
367        dsk.type = TYPE_FD;
368    dsk.slice = check_slice();
369#ifdef GET_BIOSGEOM
370    for (i = 0; i < N_BIOS_GEOM; i++)
371	bootinfo.bi_bios_geom[i] = bd_getbigeom(i);
372#endif
373    bootinfo.bi_version = BOOTINFO_VERSION;
374    bootinfo.bi_size = sizeof(bootinfo);
375
376    /* Process configuration file */
377
378    autoboot = 1;
379
380    if ((ino = lookup(PATH_CONFIG)) ||
381        (ino = lookup(PATH_DOTCONFIG))) {
382	nbyte = fsread(ino, cmd, sizeof(cmd) - 1);
383	cmd[nbyte] = '\0';
384    }
385
386    if (*cmd) {
387	memcpy(cmddup, cmd, sizeof(cmd));
388	if (parse())
389	    autoboot = 0;
390	if (!OPT_CHECK(RBX_QUIET))
391	    printf("%s: %s", PATH_CONFIG, cmddup);
392	/* Do not process this command twice */
393	*cmd = 0;
394    }
395
396    /*
397     * Try to exec stage 3 boot loader. If interrupted by a keypress,
398     * or in case of failure, try to load a kernel directly instead.
399     */
400
401    if (!kname) {
402	kname = PATH_BOOT3;
403	if (autoboot && !keyhit(3*SECOND)) {
404	    load();
405	    kname = PATH_KERNEL;
406	}
407    }
408
409    /* Present the user with the boot2 prompt. */
410
411    for (;;) {
412	if (!autoboot || !OPT_CHECK(RBX_QUIET))
413	    printf("\nFreeBSD/pc98 boot\n"
414		   "Default: %u:%s(%u,%c)%s\n"
415		   "boot: ",
416		   dsk.unit, dev_nm[dsk.type], dsk.unit,
417		   'a' + dsk.part, kname);
418	if (ioctrl & IO_SERIAL)
419	    sio_flush();
420	if (!autoboot || keyhit(3*SECOND))
421	    getstr();
422	else if (!autoboot || !OPT_CHECK(RBX_QUIET))
423	    putchar('\n');
424	autoboot = 0;
425	if (parse())
426	    putchar('\a');
427	else
428	    load();
429    }
430}
431
432/* XXX - Needed for btxld to link the boot2 binary; do not remove. */
433void
434exit(int x)
435{
436}
437
438static void
439load(void)
440{
441    union {
442	struct exec ex;
443	Elf32_Ehdr eh;
444    } hdr;
445    static Elf32_Phdr ep[2];
446    static Elf32_Shdr es[2];
447    caddr_t p;
448    ufs_ino_t ino;
449    uint32_t addr;
450    int i, j;
451
452    if (!(ino = lookup(kname))) {
453	if (!ls)
454	    printf("No %s\n", kname);
455	return;
456    }
457    if (xfsread(ino, &hdr, sizeof(hdr)))
458	return;
459
460    if (N_GETMAGIC(hdr.ex) == ZMAGIC) {
461	addr = hdr.ex.a_entry & 0xffffff;
462	p = PTOV(addr);
463	fs_off = PAGE_SIZE;
464	if (xfsread(ino, p, hdr.ex.a_text))
465	    return;
466	p += roundup2(hdr.ex.a_text, PAGE_SIZE);
467	if (xfsread(ino, p, hdr.ex.a_data))
468	    return;
469    } else if (IS_ELF(hdr.eh)) {
470	fs_off = hdr.eh.e_phoff;
471	for (j = i = 0; i < hdr.eh.e_phnum && j < 2; i++) {
472	    if (xfsread(ino, ep + j, sizeof(ep[0])))
473		return;
474	    if (ep[j].p_type == PT_LOAD)
475		j++;
476	}
477	for (i = 0; i < 2; i++) {
478	    p = PTOV(ep[i].p_paddr & 0xffffff);
479	    fs_off = ep[i].p_offset;
480	    if (xfsread(ino, p, ep[i].p_filesz))
481		return;
482	}
483	p += roundup2(ep[1].p_memsz, PAGE_SIZE);
484	bootinfo.bi_symtab = VTOP(p);
485	if (hdr.eh.e_shnum == hdr.eh.e_shstrndx + 3) {
486	    fs_off = hdr.eh.e_shoff + sizeof(es[0]) *
487		(hdr.eh.e_shstrndx + 1);
488	    if (xfsread(ino, &es, sizeof(es)))
489		return;
490	    for (i = 0; i < 2; i++) {
491		*(Elf32_Word *)p = es[i].sh_size;
492		p += sizeof(es[i].sh_size);
493		fs_off = es[i].sh_offset;
494		if (xfsread(ino, p, es[i].sh_size))
495		    return;
496		p += es[i].sh_size;
497	    }
498	}
499	addr = hdr.eh.e_entry & 0xffffff;
500	bootinfo.bi_esymtab = VTOP(p);
501    } else {
502	printf("Invalid %s\n", "format");
503	return;
504    }
505
506    bootinfo.bi_kernelname = VTOP(kname);
507    bootinfo.bi_bios_dev = dsk.daua;
508    __exec((caddr_t)addr, RB_BOOTINFO | (opts & RBX_MASK),
509	   MAKEBOOTDEV(dev_maj[dsk.type], dsk.slice, dsk.unit, dsk.part),
510	   0, 0, 0, VTOP(&bootinfo));
511}
512
513static int
514parse()
515{
516    char *arg = cmd;
517    char *ep, *p, *q;
518    const char *cp;
519    unsigned int drv;
520    int c, i, j;
521
522    while ((c = *arg++)) {
523	if (c == ' ' || c == '\t' || c == '\n')
524	    continue;
525	for (p = arg; *p && *p != '\n' && *p != ' ' && *p != '\t'; p++);
526	ep = p;
527	if (*p)
528	    *p++ = 0;
529	if (c == '-') {
530	    while ((c = *arg++)) {
531		if (c == 'P') {
532		    if (*(uint8_t *)PTOV(0x481) & 0x48) {
533			cp = "yes";
534		    } else {
535			opts |= OPT_SET(RBX_DUAL) | OPT_SET(RBX_SERIAL);
536			cp = "no";
537		    }
538		    printf("Keyboard: %s\n", cp);
539		    continue;
540		} else if (c == 'S') {
541		    j = 0;
542		    while ((unsigned int)(i = *arg++ - '0') <= 9)
543			j = j * 10 + i;
544		    if (j > 0 && i == -'0') {
545			comspeed = j;
546			break;
547		    }
548		    /* Fall through to error below ('S' not in optstr[]). */
549		}
550		for (i = 0; c != optstr[i]; i++)
551		    if (i == NOPT - 1)
552			return -1;
553		opts ^= OPT_SET(flags[i]);
554	    }
555	    ioctrl = OPT_CHECK(RBX_DUAL) ? (IO_SERIAL|IO_KEYBOARD) :
556		     OPT_CHECK(RBX_SERIAL) ? IO_SERIAL : IO_KEYBOARD;
557	    if (ioctrl & IO_SERIAL)
558	        sio_init(115200 / comspeed);
559	} else {
560	    for (q = arg--; *q && *q != '('; q++);
561	    if (*q) {
562		drv = -1;
563		if (arg[1] == ':') {
564		    drv = *arg - '0';
565		    if (drv > 9)
566			return (-1);
567		    arg += 2;
568		}
569		if (q - arg != 2)
570		    return -1;
571		for (i = 0; arg[0] != dev_nm[i][0] ||
572			    arg[1] != dev_nm[i][1]; i++)
573		    if (i == NDEV - 1)
574			return -1;
575		dsk.type = i;
576		arg += 3;
577		dsk.unit = *arg - '0';
578		if (arg[1] != ',' || dsk.unit > 9)
579		    return -1;
580		arg += 2;
581		dsk.slice = WHOLE_DISK_SLICE;
582		if (arg[1] == ',') {
583		    dsk.slice = *arg - '0' + 1;
584		    if (dsk.slice > NDOSPART + 1)
585			return -1;
586		    arg += 2;
587		}
588		if (arg[1] != ')')
589		    return -1;
590		dsk.part = *arg - 'a';
591		if (dsk.part > 7)
592		    return (-1);
593		arg += 2;
594		if (drv == -1)
595		    drv = dsk.unit;
596		dsk.disk = dev_daua[dsk.type];
597		dsk.daua = dsk.disk | dsk.unit;
598		dsk_meta = 0;
599	    }
600	    if ((i = ep - arg)) {
601		if ((size_t)i >= sizeof(knamebuf))
602		    return -1;
603		memcpy(knamebuf, arg, i + 1);
604		kname = knamebuf;
605	    }
606	}
607	arg = p;
608    }
609    return 0;
610}
611
612static int
613dskread(void *buf, unsigned lba, unsigned nblk)
614{
615    struct pc98_partition *dp;
616    struct disklabel *d;
617    char *sec;
618    unsigned i;
619    uint8_t sl;
620    u_char *p;
621
622    if (!dsk_meta) {
623	sec = dmadat->secbuf;
624	set_dsk();
625	if (dsk.type == TYPE_FD)
626	    goto unsliced;
627	if (drvread(sec, DOSBBSECTOR + 1))
628	    return -1;
629	dp = (void *)(sec + DOSPARTOFF);
630	sl = dsk.slice;
631	if (sl < BASE_SLICE) {
632	    for (i = 0; i < NDOSPART; i++)
633		if (dp[i].dp_mid == DOSMID_386BSD) {
634		    sl = BASE_SLICE + i;
635		    break;
636		}
637	    dsk.slice = sl;
638	}
639	if (sl != WHOLE_DISK_SLICE) {
640	    dp += sl - BASE_SLICE;
641	    if (dp->dp_mid != DOSMID_386BSD) {
642		printf("Invalid %s\n", "slice");
643		return -1;
644	    }
645	    dsk.start = dp->dp_scyl * dsk.head * dsk.sec +
646		dp->dp_shd * dsk.sec + dp->dp_ssect;
647	}
648	if (drvread(sec, dsk.start + LABELSECTOR))
649		return -1;
650	d = (void *)(sec + LABELOFFSET);
651	if (d->d_magic != DISKMAGIC || d->d_magic2 != DISKMAGIC) {
652	    if (dsk.part != RAW_PART) {
653		printf("Invalid %s\n", "label");
654		return -1;
655	    }
656	} else {
657	    if (dsk.part >= d->d_npartitions ||
658		!d->d_partitions[dsk.part].p_size) {
659		printf("Invalid %s\n", "partition");
660		return -1;
661	    }
662	    dsk.start += d->d_partitions[dsk.part].p_offset;
663	    dsk.start -= d->d_partitions[RAW_PART].p_offset;
664	}
665    unsliced: ;
666    }
667    for (p = buf; nblk; p += 512, lba++, nblk--) {
668	if ((i = drvread(p, dsk.start + lba)))
669	    return i;
670    }
671    return 0;
672}
673
674static void
675printf(const char *fmt,...)
676{
677    va_list ap;
678    static char buf[10];
679    char *s;
680    unsigned u;
681    int c;
682
683    va_start(ap, fmt);
684    while ((c = *fmt++)) {
685	if (c == '%') {
686	    c = *fmt++;
687	    switch (c) {
688	    case 'c':
689		putchar(va_arg(ap, int));
690		continue;
691	    case 's':
692		for (s = va_arg(ap, char *); *s; s++)
693		    putchar(*s);
694		continue;
695	    case 'u':
696		u = va_arg(ap, unsigned);
697		s = buf;
698		do
699		    *s++ = '0' + u % 10U;
700		while (u /= 10U);
701		while (--s >= buf)
702		    putchar(*s);
703		continue;
704	    }
705	}
706	putchar(c);
707    }
708    va_end(ap);
709    return;
710}
711
712static void
713putchar(int c)
714{
715    if (c == '\n')
716	xputc('\r');
717    xputc(c);
718}
719
720static int
721drvread(void *buf, unsigned lba)
722{
723    static unsigned c = 0x2d5c7c2f;
724    unsigned bpc, x, cyl, head, sec;
725
726    bpc = dsk.sec * dsk.head;
727    cyl = lba / bpc;
728    x = lba % bpc;
729    head = x / dsk.sec;
730    sec = x % dsk.sec;
731
732    if (!OPT_CHECK(RBX_QUIET))
733	printf("%c\b", c = c << 8 | c >> 24);
734    v86.ctl = V86_ADDR | V86_CALLF | V86_FLAGS;
735    v86.addr = READORG;		/* call to read in boot1 */
736    v86.ecx = cyl;
737    v86.edx = (head << 8) | sec;
738    v86.edi = lba;
739    v86.ebx = 512;
740    v86.es = VTOPSEG(buf);
741    v86.ebp = VTOPOFF(buf);
742    v86int();
743    v86.ctl = V86_FLAGS;
744    if (V86_CY(v86.efl)) {
745	printf("error %u c/h/s %u/%u/%u lba %u\n", v86.eax >> 8 & 0xff,
746	       cyl, head, sec, lba);
747	return -1;
748    }
749    return 0;
750}
751
752static inline void
753delay(void)
754{
755    int i;
756
757    i = 800;
758    do {
759	outb(0x5f, 0);	/* about 600ns */
760    } while (--i >= 0);
761}
762
763static int
764keyhit(unsigned sec)
765{
766    unsigned i;
767
768    if (OPT_CHECK(RBX_NOINTR))
769	return 0;
770    for (i = 0; i < sec * 1000; i++) {
771	if (xgetc(1))
772	    return 1;
773	delay();
774    }
775    return 0;
776}
777
778static int
779xputc(int c)
780{
781    if (ioctrl & IO_KEYBOARD)
782	putc(c);
783    if (ioctrl & IO_SERIAL)
784	sio_putc(c);
785    return c;
786}
787
788static int
789getc(int fn)
790{
791    v86.addr = 0x18;
792    v86.eax = fn << 8;
793    v86int();
794    if (fn)
795	return (v86.ebx >> 8) & 0x01;
796    else
797	return v86.eax & 0xff;
798}
799
800static int
801xgetc(int fn)
802{
803    if (OPT_CHECK(RBX_NOINTR))
804	return 0;
805    for (;;) {
806	if (ioctrl & IO_KEYBOARD && getc(1))
807	    return fn ? 1 : getc(0);
808	if (ioctrl & IO_SERIAL && sio_ischar())
809	    return fn ? 1 : sio_getc();
810	if (fn)
811	    return 0;
812    }
813}
814