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use total cylinders (+1 for count, not maximum value)

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git-svn-id: https://svn.code.sf.net/p/freedos/svn/kernel/trunk@1377 6ac86273-5f31-0410-b378-82cca8765d1b
This commit is contained in:
Kenneth J Davis 2009-05-11 17:11:30 +00:00
parent c6b55c1119
commit da25cd58b4
1 changed files with 32 additions and 15 deletions
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37
kernel/initdisk.c
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@ -339,7 +339,22 @@ COUNT init_getdriveparm(UBYTE drive, bpb * pbpbarray)
/*
translate LBA sectors into CHS addressing
copied and pasted from dsk.c!
initially copied and pasted from dsk.c!
LBA to/from CHS conversion - see http://www.ata-atapi.com/ How It Works section on CHSxlat - CHS Translation
LBA (logical block address) simple 0 to N-1 used internally and with extended int 13h (BIOS)
L-CHS (logical CHS) is the CHS view when using int 13h (BIOS)
P-CHS (physical CHS) is the CHS view when directly accessing disk, should not, but could be used in BS or MBR
LBA = ( (cylinder * heads_per_cylinder + heads ) * sectors_per_track ) + sector - 1
cylinder = LBA / (heads_per_cylinder * sectors_per_track)
temp = LBA % (heads_per_cylinder * sectors_per_track)
head = temp / sectors_per_track
sector = temp % sectors_per_track + 1
where heads_per_cylinder and sectors_per_track are the current translation mode values.
cyclinder and heads are 0 to N-1 based, sector is 1 to N based
*/
void init_LBA_to_CHS(struct CHS *chs, ULONG LBA_address,
@ -747,9 +762,11 @@ StandardBios: /* old way to get parameters */
if (regs.flags & 0x01)
goto ErrorReturn;
driveParam->chs.Head = (regs.d.x >> 8) + 1;
driveParam->chs.Sector = (regs.c.x & 0x3f);
driveParam->chs.Cylinder = (regs.c.x >> 8) | ((regs.c.x & 0xc0) << 2);
/* int13h call returns max value, store as count (#) i.e. +1 for 0 based heads & cylinders */
driveParam->chs.Head = (regs.d.x >> 8) + 1; /* DH = max head value = # of heads - 1 (0-255) */
driveParam->chs.Sector = (regs.c.x & 0x3f); /* CL bits 0-5 = max sector value = # (sectors/track) - 1 (1-63) */
/* max cylinder value = # cylinders - 1 (0-1023) = [high two bits]CL7:6=cyls9:8, [low byte]CH=cyls7:0 */
driveParam->chs.Cylinder = (regs.c.x >> 8) | ((regs.c.x & 0xc0) << 2) + 1;
if (driveParam->chs.Sector == 0) {
/* happens e.g. with Bochs 1.x if no harddisk defined */
@ -760,13 +777,13 @@ StandardBios: /* old way to get parameters */
if (!(driveParam->descflags & DF_LBA))
{
driveParam->total_sectors =
min(driveParam->chs.Cylinder, 1023)
(ULONG)driveParam->chs.Cylinder
* driveParam->chs.Head * driveParam->chs.Sector;
}
driveParam->driveno = drive;
DebugPrintf(("drive parameters %02x - %04lu-%u-%u",
DebugPrintf(("drive %02Xh total: C = %u, H = %u, S = %u,",
drive,
driveParam->chs.Cylinder,
driveParam->chs.Head, driveParam->chs.Sector));
@ -986,8 +1003,8 @@ int Read1LBASector(struct DriveParamS *driveParam, unsigned drive,
#if 0
if (LBA_address >= driveParam->total_sectors)
{
printf("LBA-Transfer error : address overflow = %lu > %lu max\n",
LBA_address + 1, driveParam->total_sectors);
printf("LBA-Transfer error : address overflow = %lu, > %lu total sectors\n",
LBA_address, driveParam->total_sectors);
return 1;
}
#endif
@ -1021,7 +1038,7 @@ int Read1LBASector(struct DriveParamS *driveParam, unsigned drive,
if (chs.Cylinder > 1023)
{
printf("LBA-Transfer error : cylinder %u > 1023\n", chs.Cylinder);
printf("LBA-Transfer error : address = %lu, cylinder %u > 1023\n", LBA_address, chs.Cylinder);
return 1;
}
@ -1078,7 +1095,7 @@ strange_restart:
if (Read1LBASector
(&driveParam, drive, RelSectorOffset, InitDiskTransferBuffer))
{
printf("Error reading partition table drive %02x sector %lu", drive,
printf("Error reading partition table drive %02Xh sector %lu", drive,
RelSectorOffset);
return PartitionsToIgnore;
}