/*
* Quiz the BIOS for disk devices, save a little info about them.
*/
static int
bd_init(void)
{
int base, unit;
int da_drive=0, n=-0x10;
/* sequence 0x90, 0x80, 0xa0 */
for (base = 0x90; base <= 0xa0; base += n, n += 0x30) {
for (unit = base; (nbdinfo < MAXBDDEV) || ((unit & 0x0f) < 4); unit++) {
bdinfo[nbdinfo].bd_open = 0;
bdinfo[nbdinfo].bd_bcache = NULL;
bdinfo[nbdinfo].bd_unit = unit;
bdinfo[nbdinfo].bd_flags = (unit & 0xf0) == 0x90 ? BD_FLOPPY : 0;
if (!bd_int13probe(&bdinfo[nbdinfo])){
if (((unit & 0xf0) == 0x90 && (unit & 0x0f) < 4) ||
((unit & 0xf0) == 0xa0 && (unit & 0x0f) < 6))
continue; /* Target IDs are not contiguous. */
else
break;
}
if (bdinfo[nbdinfo].bd_flags & BD_FLOPPY){
/* available 1.44MB access? */
if (*(u_char *)PTOV(0xA15AE) & (1<<(unit & 0xf))) {
/* boot media 1.2MB FD? */
if ((*(u_char *)PTOV(0xA1584) & 0xf0) != 0x90)
bdinfo[nbdinfo].bd_unit = 0x30 + (unit & 0xf);
}
}
else {
if ((unit & 0xF0) == 0xA0) /* SCSI HD or MO */
bdinfo[nbdinfo].bd_da_unit = da_drive++;
}
/* XXX we need "disk aliases" to make this simpler */
printf("BIOS drive %c: is disk%d\n",
'A' + nbdinfo, nbdinfo);
nbdinfo++;
}
}
bcache_add_dev(nbdinfo);
return(0);
}
/*
* Quiz the BIOS for disk devices, save a little info about them.
*
* XXX should we be consulting the BIOS equipment list, specifically
* the value at 0x475?
*/
static int
bd_init(void)
{
int base, unit;
/* sequence 0, 0x80 */
for (base = 0; base <= 0x80; base += 0x80) {
for (unit = base; (nbdinfo < MAXBDDEV); unit++) {
bdinfo[nbdinfo].bd_unit = unit;
bdinfo[nbdinfo].bd_flags = (unit < 0x80) ? BD_FLOPPY : 0;
/* XXX add EDD probes */
if (!bd_int13probe(&bdinfo[nbdinfo]))
break;
/* XXX we need "disk aliases" to make this simpler */
printf("BIOS drive %c: is disk%d\n",
(unit < 0x80) ? ('A' + unit) : ('C' + unit - 0x80), nbdinfo);
nbdinfo++;
}
}
return(0);
}
