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[FREELOADER]

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- Remove duplicated code
- Add back the Mac hack but use 0x8A for the lowest CD-ROM drive number instead of 0x90

svn path=/trunk/; revision=47576
This commit is contained in:
Cameron Gutman 2010-06-04 20:22:29 +00:00
parent 63ce635b0f
commit fc022a8506
2 changed files with 30 additions and 82 deletions
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42
reactos/boot/freeldr/freeldr/arch/i386/i386disk.c
View file

@ -51,10 +51,32 @@ BOOLEAN DiskResetController(ULONG DriveNumber)
BOOLEAN DiskInt13ExtensionsSupported(ULONG DriveNumber)
{
static ULONG LastDriveNumber = 0xffffffff;
static BOOLEAN LastSupported;
REGS RegsIn;
REGS RegsOut;
DPRINTM(DPRINT_DISK, "DiskInt13ExtensionsSupported()\n");
DPRINTM(DPRINT_DISK, "PcDiskInt13ExtensionsSupported()\n");
if (DriveNumber == LastDriveNumber)
{
DPRINTM(DPRINT_DISK, "Using cached value %s for drive 0x%x\n", LastSupported ? "TRUE" : "FALSE", DriveNumber);
return LastSupported;
}
// Some BIOSes report that extended disk access functions are not supported
// when booting from a CD (e.g. Phoenix BIOS v6.00PG and Insyde BIOS shipping
// with Intel Macs). Therefore we just return TRUE if we're booting from a CD -
// we can assume that all El Torito capable BIOSes support INT 13 extensions.
// We simply detect whether we're booting from CD by checking whether the drive
// number is >= 0x8A. It's 0x90 on the Insyde BIOS, and 0x9F on most other BIOSes.
if (DriveNumber >= 0x8A)
{
LastSupported = TRUE;
return TRUE;
}
LastDriveNumber = DriveNumber;
// IBM/MS INT 13 Extensions - INSTALLATION CHECK
// AH = 41h
@ -90,35 +112,27 @@ BOOLEAN DiskInt13ExtensionsSupported(ULONG DriveNumber)
if (!INT386_SUCCESS(RegsOut))
{
// CF set on error (extensions not supported)
LastSupported = FALSE;
return FALSE;
}
if (RegsOut.w.bx != 0xAA55)
{
// BX = AA55h if installed
LastSupported = FALSE;
return FALSE;
}
// Note:
// The original check is too strict because some BIOSes report that
// extended disk access functions are not suported when booting
// from a CD (e.g. Phoenix BIOS v6.00PG). Argh!
#if 0
if (!(RegsOut.w.cx & 0x0001))
{
// CX = API subset support bitmap
// Bit 0, extended disk access functions (AH=42h-44h,47h,48h) supported
return FALSE;
}
#endif
// Use this relaxed check instead
if (RegsOut.w.cx == 0x0000)
{
// CX = API subset support bitmap
DbgPrint("Suspicious API subset support bitmap 0x%x on device 0x%lx\n", RegsOut.w.cx, DriveNumber);
LastSupported = FALSE;
return FALSE;
}
LastSupported = TRUE;
return TRUE;
}

70
reactos/boot/freeldr/freeldr/arch/i386/pcdisk.c
View file

@ -264,72 +264,6 @@ static BOOLEAN PcDiskReadLogicalSectorsCHS(ULONG DriveNumber, ULONGLONG SectorNu
return TRUE;
}
static BOOLEAN PcDiskInt13ExtensionsSupported(ULONG DriveNumber)
{
static ULONG LastDriveNumber = 0xffffffff;
static BOOLEAN LastSupported;
REGS RegsIn;
REGS RegsOut;
DPRINTM(DPRINT_DISK, "PcDiskInt13ExtensionsSupported()\n");
if (DriveNumber == LastDriveNumber)
{
DPRINTM(DPRINT_DISK, "Using cached value %s for drive 0x%x\n", LastSupported ? "TRUE" : "FALSE", DriveNumber);
return LastSupported;
}
LastDriveNumber = DriveNumber;
// IBM/MS INT 13 Extensions - INSTALLATION CHECK
// AH = 41h
// BX = 55AAh
// DL = drive (80h-FFh)
// Return:
// CF set on error (extensions not supported)
// AH = 01h (invalid function)
// CF clear if successful
// BX = AA55h if installed
// AH = major version of extensions
// 01h = 1.x
// 20h = 2.0 / EDD-1.0
// 21h = 2.1 / EDD-1.1
// 30h = EDD-3.0
// AL = internal use
// CX = API subset support bitmap
// DH = extension version (v2.0+ ??? -- not present in 1.x)
//
// Bitfields for IBM/MS INT 13 Extensions API support bitmap
// Bit 0, extended disk access functions (AH=42h-44h,47h,48h) supported
// Bit 1, removable drive controller functions (AH=45h,46h,48h,49h,INT 15/AH=52h) supported
// Bit 2, enhanced disk drive (EDD) functions (AH=48h,AH=4Eh) supported
// extended drive parameter table is valid
// Bits 3-15 reserved
RegsIn.b.ah = 0x41;
RegsIn.w.bx = 0x55AA;
RegsIn.b.dl = DriveNumber;
// Reset the disk controller
Int386(0x13, &RegsIn, &RegsOut);
if (!INT386_SUCCESS(RegsOut))
{
// CF set on error (extensions not supported)
LastSupported = FALSE;
return FALSE;
}
if (RegsOut.w.bx != 0xAA55)
{
// BX = AA55h if installed
LastSupported = FALSE;
return FALSE;
}
LastSupported = TRUE;
return TRUE;
}
BOOLEAN PcDiskReadLogicalSectors(ULONG DriveNumber, ULONGLONG SectorNumber, ULONG SectorCount, PVOID Buffer)
{
@ -340,9 +274,9 @@ BOOLEAN PcDiskReadLogicalSectors(ULONG DriveNumber, ULONGLONG SectorNumber, ULON
// If so then check to see if Int13 extensions work
// If they do then use them, otherwise default back to BIOS calls
//
if ((DriveNumber >= 0x80) && PcDiskInt13ExtensionsSupported(DriveNumber))
if ((DriveNumber >= 0x80) && DiskInt13ExtensionsSupported(DriveNumber))
{
DPRINTM(DPRINT_DISK, "Using Int 13 Extensions for read. PcDiskInt13ExtensionsSupported(%d) = %s\n", DriveNumber, PcDiskInt13ExtensionsSupported(DriveNumber) ? "TRUE" : "FALSE");
DPRINTM(DPRINT_DISK, "Using Int 13 Extensions for read. DiskInt13ExtensionsSupported(%d) = %s\n", DriveNumber, DiskInt13ExtensionsSupported(DriveNumber) ? "TRUE" : "FALSE");
//
// LBA is easy, nothing to calculate