[cgutman] 47576: [FREELOADER] - Remove duplicated code - Add back the Mac hack but use 0x8A for the lowest CD-ROM drive number instead of 0x90
Author: cgutman Date: Fri Jun 4 22:22:29 2010 New Revision: 47576
URL: http://svn.reactos.org/svn/reactos?rev=47576&view=rev Log: [FREELOADER] - Remove duplicated code - Add back the Mac hack but use 0x8A for the lowest CD-ROM drive number instead of 0x90
Modified: trunk/reactos/boot/freeldr/freeldr/arch/i386/i386disk.c trunk/reactos/boot/freeldr/freeldr/arch/i386/pcdisk.c
Modified: trunk/reactos/boot/freeldr/freeldr/arch/i386/i386disk.c URL: http://svn.reactos.org/svn/reactos/trunk/reactos/boot/freeldr/freeldr/arch/i... ============================================================================== --- trunk/reactos/boot/freeldr/freeldr/arch/i386/i386disk.c [iso-8859-1] (original) +++ trunk/reactos/boot/freeldr/freeldr/arch/i386/i386disk.c [iso-8859-1] Fri Jun 4 22:22:29 2010 @@ -51,10 +51,32 @@
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 @@ if (!INT386_SUCCESS(RegsOut)) { // CF set on error (extensions not supported) + LastSupported = FALSE; return FALSE; }
if (RegsOut.w.bx != 0xAA55) { // BX = AA55h if installed - 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 + LastSupported = FALSE; + return FALSE; + } + 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 - return FALSE; - } - + 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; }
Modified: trunk/reactos/boot/freeldr/freeldr/arch/i386/pcdisk.c URL: http://svn.reactos.org/svn/reactos/trunk/reactos/boot/freeldr/freeldr/arch/i... ============================================================================== --- trunk/reactos/boot/freeldr/freeldr/arch/i386/pcdisk.c [iso-8859-1] (original) +++ trunk/reactos/boot/freeldr/freeldr/arch/i386/pcdisk.c [iso-8859-1] Fri Jun 4 22:22:29 2010 @@ -264,72 +264,6 @@ 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 @@ // 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)) - { - DPRINTM(DPRINT_DISK, "Using Int 13 Extensions for read. PcDiskInt13ExtensionsSupported(%d) = %s\n", DriveNumber, PcDiskInt13ExtensionsSupported(DriveNumber) ? "TRUE" : "FALSE"); + if ((DriveNumber >= 0x80) && DiskInt13ExtensionsSupported(DriveNumber)) + { + DPRINTM(DPRINT_DISK, "Using Int 13 Extensions for read. DiskInt13ExtensionsSupported(%d) = %s\n", DriveNumber, DiskInt13ExtensionsSupported(DriveNumber) ? "TRUE" : "FALSE");
// // LBA is easy, nothing to calculate
-
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