int is_no_emulation(int drive)
{
struct packet
{
unsigned char packet_size;
unsigned char media_type;
unsigned char drive_num;
unsigned char ctrlr_index;
unsigned long lba;
unsigned short device_spec;
unsigned short buffer_segment;
unsigned short load_segment;
unsigned short sector_count;
unsigned char cyl_count;
unsigned char sec_count;
unsigned char head_count;
unsigned char reseved;
} __attribute__((packed));
static struct packet pkt;
bzero(&pkt, sizeof(pkt));
pkt.packet_size = 0x13;
bb.intno = 0x13;
bb.eax.r.h = 0x4b;
bb.eax.r.l = 0x01; // subfunc: get info
bb.edx.r.l = drive;
bb.esi.rr = NORMALIZED_OFFSET((unsigned)&pkt);
bb.ds = NORMALIZED_SEGMENT((unsigned)&pkt);
bios(&bb);
#if DEBUG
printf("el_torito info drive %x\n", drive);
printf("--> cf %x, eax %x\n", bb.flags.cf, bb.eax.rr);
printf("pkt_size: %x\n", pkt.packet_size);
printf("media_type: %x\n", pkt.media_type);
printf("drive_num: %x\n", pkt.drive_num);
printf("device_spec: %x\n", pkt.device_spec);
printf("press a key->\n");
getchar();
#endif
/* Some BIOSes erroneously return cf = 1 */
/* Just check to see if the drive number is the same. */
if (pkt.drive_num == drive && (pkt.media_type & 0x0F) == 0)
{
return 1; // We are in no-emulation mode.
}
return 0;
}
int get_drive_info(int drive, struct driveInfo *dp)
{
boot_drive_info_t *di = &dp->di;
int ret = 0;
#if UNUSED
if (maxhd == 0)
{
bb.intno = 0x13;
bb.eax.r.h = 0x08;
bb.edx.r.l = 0x80;
bios(&bb);
if (bb.flags.cf == 0)
maxhd = 0x7f + bb.edx.r.l;
};
if (drive > maxhd)
return 0;
#endif
bzero(dp, sizeof(struct driveInfo));
dp->biosdev = drive;
/* Check for El Torito no-emulation mode. */
dp->no_emulation = is_no_emulation(drive);
/* Check drive for EBIOS support. */
bb.intno = 0x13;
bb.eax.r.h = 0x41;
bb.edx.r.l = drive;
bb.ebx.rr = 0x55aa;
bios(&bb);
if ((bb.ebx.rr == 0xaa55) && (bb.flags.cf == 0))
dp->uses_ebios = bb.ecx.r.l; // Get flags for supported operations.
if (dp->uses_ebios & (EBIOS_ENHANCED_DRIVE_INFO | EBIOS_LOCKING_ACCESS | EBIOS_FIXED_DISK_ACCESS))
{
// Get EBIOS drive info.
static struct drive_params params;
params.buf_size = sizeof(params);
bb.intno = 0x13;
bb.eax.r.h = 0x48;
bb.edx.r.l = drive;
bb.esi.rr = NORMALIZED_OFFSET((unsigned)¶ms);
bb.ds = NORMALIZED_SEGMENT((unsigned)¶ms);
bios(&bb);
if (bb.flags.cf != 0 /* || params.phys_sectors < 2097152 */)
{
dp->uses_ebios = 0;
di->params.buf_size = 1;
}
else
{
bcopy(¶ms, &di->params, sizeof(params));
if (drive >= BASE_HD_DRIVE &&
(dp->uses_ebios & EBIOS_ENHANCED_DRIVE_INFO) &&
di->params.buf_size >= 30 &&
!(di->params.dpte_offset == 0xFFFF && di->params.dpte_segment == 0xFFFF))
{
void *ptr = (void *)(di->params.dpte_offset + ((unsigned int)di->params.dpte_segment << 4));
bcopy(ptr, &di->dpte, sizeof(di->dpte));
}
}
}
if (dp->no_emulation)
{
/* Some BIOSes give us erroneous EBIOS support information.
* Assume that if you're on a CD, then you can use
* EBIOS disk calls.
*/
dp->uses_ebios |= EBIOS_FIXED_DISK_ACCESS;
}
#if DEBUG
print_drive_info(di);
printf("uses_ebios = 0x%x\n", dp->uses_ebios);
printf("result %d\n", ret);
printf("press a key->\n");getc();
#endif
if (ret == 0)
dp->valid = 1;
return ret;
}
int ebiosread(int dev, unsigned long long sec, int count)
{
int i;
static struct
{
unsigned char size;
unsigned char reserved;
unsigned char numblocks;
unsigned char reserved2;
unsigned short bufferOffset;
unsigned short bufferSegment;
unsigned long long startblock;
} addrpacket __attribute__((aligned(16))) = {0};
addrpacket.size = sizeof(addrpacket);
for (i = 0; ;)
{
bb.intno = 0x13;
bb.eax.r.h = 0x42;
bb.edx.r.l = dev;
bb.esi.rr = NORMALIZED_OFFSET((unsigned)&addrpacket);
bb.ds = NORMALIZED_SEGMENT((unsigned)&addrpacket);
addrpacket.reserved = addrpacket.reserved2 = 0;
addrpacket.numblocks = count;
addrpacket.bufferOffset = OFFSET(ptov(BIOS_ADDR));
addrpacket.bufferSegment = SEGMENT(ptov(BIOS_ADDR));
addrpacket.startblock = sec;
bios(&bb);
// In case of a successful call, make sure we set AH (return code) to zero.
if (bb.flags.cf == 0)
{
bb.eax.r.h = 0;
}
// Now we can really check for the return code (AH) value.
if ((bb.eax.r.h == 0x00) || (i++ >= 5))
{
break;
}
// Reset disk subsystem and try again.
bb.eax.r.h = 0x00;
bios(&bb);
}
return bb.eax.r.h;
}
//==============================================================================
void putc(int ch)
{
bb.intno = 0x10;
bb.ebx.r.h = 0x00; /* background black */
bb.ebx.r.l = 0x0F; /* foreground white */
bb.eax.r.h = 0x0e;
bb.eax.r.l = ch;
bios(&bb);
}
unsigned long getMemoryMap(MemoryRange * rangeArray, unsigned long maxRangeCount, unsigned long * conMemSizePtr, unsigned long * extMemSizePtr)
{
#define kMemoryMapSignature 'SMAP'
#define kDescriptorSizeMin 20
MemoryRange * range = (MemoryRange *)BIOS_ADDR;
unsigned long count = 0;
unsigned long long conMemSize = 0;
unsigned long long extMemSize = 0;
// Prepare for the INT15 E820h call. Each call returns a single
// memory range. A continuation value is returned that must be
// provided on a subsequent call to fetch the next range.
//
// Certain BIOSes (Award 6.00PG) expect the upper word in EAX
// to be cleared on entry, otherwise only a single range will
// be reported.
//
// Some BIOSes will simply ignore the value of ECX on entry.
// Probably best to keep its value at 20 to avoid surprises.
//printf("Get memory map 0x%x, %d\n", rangeArray);getc();
if (maxRangeCount > (BIOS_LEN / sizeof(MemoryRange)))
maxRangeCount = (BIOS_LEN / sizeof(MemoryRange));
bb.ebx.rx = 0; // Initial continuation value must be zero.
while (count < maxRangeCount)
{
bb.intno = 0x15;
bb.eax.rx = 0xe820;
bb.ecx.rx = kDescriptorSizeMin;
bb.edx.rx = kMemoryMapSignature;
bb.edi.rr = NORMALIZED_OFFSET( (unsigned long) range );
bb.es = NORMALIZED_SEGMENT( (unsigned long) range );
bios(&bb);
// Check for errors.
if ( bb.flags.cf || bb.eax.rx != kMemoryMapSignature
|| bb.ecx.rx != kDescriptorSizeMin )
{
//printf("Got an error %x %x %x\n", bb.flags.cf,
// bb.eax.rx, bb.ecx.rx);
break;
}
// Tally up the conventional/extended memory sizes.
if (range->type == kMemoryRangeUsable || range->type == kMemoryRangeACPI ||
range->type == kMemoryRangeNVS )
{
// Tally the conventional memory ranges.
if (range->base + range->length <= 0xa0000)
conMemSize += range->length;
// Record the top of extended memory.
if (range->base >= EXTENDED_ADDR)
extMemSize += range->length;
}
range++;
count++;
// Is this the last address range?
if ( bb.ebx.rx == 0 ) {
//printf("last range\n");
break;
}
}
*conMemSizePtr = conMemSize / 1024; // size in KB
*extMemSizePtr = extMemSize / 1024; // size in KB
// Copy out data
bcopy((char *)BIOS_ADDR, rangeArray, ((char *)range - (char *)BIOS_ADDR));
#if DEBUG
{
int i;
printf("%d total ranges\n", count);getc();
for (i=0, range = rangeArray; i<count; i++, range++)
{
printf("range: type %d, base 0x%x, length 0x%x\n",
range->type, (unsigned int)range->base, (unsigned int)range->length);
getc();
}
}
#endif
return count;
}
