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[NTVDM]

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When the VGA memory map is A0000-BFFFF, mirror the bottom 64 KB into the top.
This should take care of all VGA addressing problems.


svn path=/trunk/; revision=67377
This commit is contained in:
Aleksandar Andrejevic 2015-04-24 01:05:50 +00:00
parent 492d1e96d1
commit 3a9b91f9d7
1 changed files with 3 additions and 7 deletions
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10
reactos/subsystems/mvdm/ntvdm/hardware/video/vga.c
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@ -22,7 +22,7 @@
/* PRIVATE VARIABLES **********************************************************/
static CONST DWORD MemoryBase[] = { 0xA0000, 0xA0000, 0xB0000, 0xB8000 };
static CONST DWORD MemoryLimit[] = { 0xAFFFF, 0xAFFFF, 0xB7FFF, 0xBFFFF };
static CONST DWORD MemoryLimit[] = { 0xBFFFF, 0xAFFFF, 0xB7FFF, 0xBFFFF };
/*
* Activate this line if you want to use the real
@ -622,7 +622,7 @@ static inline DWORD VgaGetAddressSize(VOID)
static inline DWORD VgaTranslateReadAddress(DWORD Address)
{
DWORD Offset = Address - VgaGetVideoBaseAddress();
DWORD Offset = LOWORD(Address - VgaGetVideoBaseAddress());
BYTE Plane;
/* Check for chain-4 and odd-even mode */
@ -649,7 +649,7 @@ static inline DWORD VgaTranslateReadAddress(DWORD Address)
static inline DWORD VgaTranslateWriteAddress(DWORD Address)
{
DWORD Offset = Address - VgaGetVideoBaseAddress();
DWORD Offset = LOWORD(Address - VgaGetVideoBaseAddress());
/* Check for chain-4 and odd-even mode */
if (VgaSeqRegisters[VGA_SEQ_MEM_REG] & VGA_SEQ_MEM_C4)
@ -1905,8 +1905,6 @@ VOID NTAPI VgaReadMemory(ULONG Address, PVOID Buffer, ULONG Size)
PUCHAR BufPtr = (PUCHAR)Buffer;
DPRINT("VgaReadMemory: Address 0x%08X, Size %lu\n", Address, Size);
Address = min(max(Address, VgaGetVideoBaseAddress()), VgaGetVideoLimitAddress());
Size = min(Size, VgaGetVideoLimitAddress() - Address + 1);
/* Ignore if video RAM access is disabled */
if ((VgaMiscRegister & VGA_MISC_RAM_ENABLED) == 0) return;
@ -1934,8 +1932,6 @@ BOOLEAN NTAPI VgaWriteMemory(ULONG Address, PVOID Buffer, ULONG Size)
PUCHAR BufPtr = (PUCHAR)Buffer;
DPRINT("VgaWriteMemory: Address 0x%08X, Size %lu\n", Address, Size);
Address = min(max(Address, VgaGetVideoBaseAddress()), VgaGetVideoLimitAddress());
Size = min(Size, VgaGetVideoLimitAddress() - Address + 1);
/* Ignore if video RAM access is disabled */
if ((VgaMiscRegister & VGA_MISC_RAM_ENABLED) == 0) return TRUE;