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Patch by Brian Palmer:
Properly handle a memory hole below 16MB, which some machines have.

svn path=/trunk/; revision=53796
This commit is contained in:
Timo Kreuzer 2011-09-21 21:48:44 +00:00
parent 84727b099d
commit 994898f151
1 changed files with 100 additions and 80 deletions
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180
reactos/boot/freeldr/freeldr/arch/i386/pcmem.c
View file

@ -27,95 +27,100 @@
DBG_DEFAULT_CHANNEL(MEMORY); DBG_DEFAULT_CHANNEL(MEMORY);
static ULONG static
PcMemGetExtendedMemorySize(VOID) BOOLEAN
GetExtendedMemoryConfiguration(ULONG* pMemoryAtOneMB /* in KB */, ULONG* pMemoryAtSixteenMB /* in 64KB */)
{ {
REGS RegsIn; REGS RegsIn;
REGS RegsOut; REGS RegsOut;
ULONG MemorySize;
TRACE("GetExtendedMemorySize()\n"); TRACE("GetExtendedMemoryConfiguration()\n");
/* Int 15h AX=E801h *pMemoryAtOneMB = 0;
* Phoenix BIOS v4.0 - GET MEMORY SIZE FOR >64M CONFIGURATIONS *pMemoryAtSixteenMB = 0;
*
* AX = E801h
* Return:
* CF clear if successful
* AX = extended memory between 1M and 16M, in K (max 3C00h = 15MB)
* BX = extended memory above 16M, in 64K blocks
* CX = configured memory 1M to 16M, in K
* DX = configured memory above 16M, in 64K blocks
* CF set on error
*/
RegsIn.w.ax = 0xE801;
Int386(0x15, &RegsIn, &RegsOut);
TRACE("Int15h AX=E801h\n"); // Int 15h AX=E801h
TRACE("AX = 0x%x\n", RegsOut.w.ax); // Phoenix BIOS v4.0 - GET MEMORY SIZE FOR >64M CONFIGURATIONS
TRACE("BX = 0x%x\n", RegsOut.w.bx); //
TRACE("CX = 0x%x\n", RegsOut.w.cx); // AX = E801h
TRACE("DX = 0x%x\n", RegsOut.w.dx); // Return:
TRACE("CF set = %s\n\n", (RegsOut.x.eflags & EFLAGS_CF) ? "TRUE" : "FALSE"); // CF clear if successful
// AX = extended memory between 1M and 16M, in K (max 3C00h = 15MB)
// BX = extended memory above 16M, in 64K blocks
// CX = configured memory 1M to 16M, in K
// DX = configured memory above 16M, in 64K blocks
// CF set on error
RegsIn.w.ax = 0xE801;
Int386(0x15, &RegsIn, &RegsOut);
if (INT386_SUCCESS(RegsOut)) TRACE("Int15h AX=E801h\n");
TRACE("AX = 0x%x\n", RegsOut.w.ax);
TRACE("BX = 0x%x\n", RegsOut.w.bx);
TRACE("CX = 0x%x\n", RegsOut.w.cx);
TRACE("DX = 0x%x\n", RegsOut.w.dx);
TRACE("CF set = %s\n\n", (RegsOut.x.eflags & EFLAGS_CF) ? "TRUE" : "FALSE");
if (INT386_SUCCESS(RegsOut))
{ {
/* If AX=BX=0000h the use CX and DX */ // If AX=BX=0000h the use CX and DX
if (RegsOut.w.ax == 0) if (RegsOut.w.ax == 0)
{ {
/* Return extended memory size in K */ // Return extended memory size in K
MemorySize = RegsOut.w.dx * 64; *pMemoryAtSixteenMB = RegsOut.w.dx;
MemorySize += RegsOut.w.cx; *pMemoryAtOneMB = RegsOut.w.cx;
return MemorySize; return TRUE;
} }
else else
{ {
/* Return extended memory size in K */ // Return extended memory size in K
MemorySize = RegsOut.w.bx * 64; *pMemoryAtSixteenMB = RegsOut.w.bx;
MemorySize += RegsOut.w.ax; *pMemoryAtOneMB = RegsOut.w.ax;
return MemorySize; return TRUE;
} }
} }
/* If we get here then Int15 Func E801h didn't work */ // If we get here then Int15 Func E801h didn't work
/* So try Int15 Func 88h */ // So try Int15 Func 88h
// Int 15h AH=88h
// SYSTEM - GET EXTENDED MEMORY SIZE (286+)
//
// AH = 88h
// Return:
// CF clear if successful
// AX = number of contiguous KB starting at absolute address 100000h
// CF set on error
// AH = status
// 80h invalid command (PC,PCjr)
// 86h unsupported function (XT,PS30)
RegsIn.b.ah = 0x88;
Int386(0x15, &RegsIn, &RegsOut);
/* Int 15h AH=88h TRACE("Int15h AH=88h\n");
* SYSTEM - GET EXTENDED MEMORY SIZE (286+) TRACE("AX = 0x%x\n", RegsOut.w.ax);
* TRACE("CF set = %s\n\n", (RegsOut.x.eflags & EFLAGS_CF) ? "TRUE" : "FALSE");
* AH = 88h
* Return:
* CF clear if successful
* AX = number of contiguous KB starting at absolute address 100000h
* CF set on error
* AH = status
* 80h invalid command (PC,PCjr)
* 86h unsupported function (XT,PS30)
*/
RegsIn.b.ah = 0x88;
Int386(0x15, &RegsIn, &RegsOut);
TRACE("Int15h AH=88h\n"); if (INT386_SUCCESS(RegsOut) && RegsOut.w.ax != 0)
TRACE("AX = 0x%x\n", RegsOut.w.ax);
TRACE("CF set = %s\n\n", (RegsOut.x.eflags & EFLAGS_CF) ? "TRUE" : "FALSE");
if (INT386_SUCCESS(RegsOut) && RegsOut.w.ax != 0)
{ {
MemorySize = RegsOut.w.ax; *pMemoryAtOneMB = RegsOut.w.ax;
return MemorySize; return TRUE;
} }
/* If we get here then Int15 Func 88h didn't work */ // If we get here then Int15 Func 88h didn't work
/* So try reading the CMOS */ // So try reading the CMOS
WRITE_PORT_UCHAR((PUCHAR)0x70, 0x31); WRITE_PORT_UCHAR((PUCHAR)0x70, 0x31);
MemorySize = READ_PORT_UCHAR((PUCHAR)0x71); *pMemoryAtOneMB = READ_PORT_UCHAR((PUCHAR)0x71);
MemorySize = (MemorySize & 0xFFFF); *pMemoryAtOneMB = (*pMemoryAtOneMB & 0xFFFF);
MemorySize = (MemorySize << 8); *pMemoryAtOneMB = (*pMemoryAtOneMB << 8);
TRACE("Int15h Failed\n"); TRACE("Int15h Failed\n");
TRACE("CMOS reports: 0x%x\n", MemorySize); TRACE("CMOS reports: 0x%x\n", *pMemoryAtOneMB);
return MemorySize; if (*pMemoryAtOneMB != 0)
{
return TRUE;
}
return FALSE;
} }
static ULONG static ULONG
@ -228,21 +233,36 @@ ULONG
PcMemGetMemoryMap(PBIOS_MEMORY_MAP BiosMemoryMap, ULONG MaxMemoryMapSize) PcMemGetMemoryMap(PBIOS_MEMORY_MAP BiosMemoryMap, ULONG MaxMemoryMapSize)
{ {
ULONG EntryCount; ULONG EntryCount;
ULONG ExtendedMemorySizeAtOneMB;
ULONG ExtendedMemorySizeAtSixteenMB;
EntryCount = PcMemGetBiosMemoryMap(BiosMemoryMap, MaxMemoryMapSize); EntryCount = PcMemGetBiosMemoryMap(BiosMemoryMap, MaxMemoryMapSize);
/* If the BIOS didn't provide a memory map, synthesize one */ /* If the BIOS didn't provide a memory map, synthesize one */
if (0 == EntryCount && 2 <= MaxMemoryMapSize) if (0 == EntryCount && 3 <= MaxMemoryMapSize)
{ {
/* Conventional memory */ GetExtendedMemoryConfiguration(&ExtendedMemorySizeAtOneMB, &ExtendedMemorySizeAtSixteenMB);
BiosMemoryMap[0].BaseAddress = 0;
BiosMemoryMap[0].Length = PcMemGetConventionalMemorySize() * 1024; /* Conventional memory */
BiosMemoryMap[0].Type = BiosMemoryUsable; BiosMemoryMap[EntryCount].BaseAddress = 0;
/* Extended memory */ BiosMemoryMap[EntryCount].Length = PcMemGetConventionalMemorySize() * 1024;
BiosMemoryMap[1].BaseAddress = 1024 * 1024; BiosMemoryMap[EntryCount].Type = BiosMemoryUsable;
BiosMemoryMap[1].Length = PcMemGetExtendedMemorySize() * 1024; EntryCount++;
BiosMemoryMap[1].Type = BiosMemoryUsable;
EntryCount = 2; /* Extended memory at 1MB */
BiosMemoryMap[EntryCount].BaseAddress = 1024 * 1024;
BiosMemoryMap[EntryCount].Length = ExtendedMemorySizeAtOneMB * 1024;
BiosMemoryMap[EntryCount].Type = BiosMemoryUsable;
EntryCount++;
if (ExtendedMemorySizeAtSixteenMB != 0)
{
/* Extended memory at 16MB */
BiosMemoryMap[EntryCount].BaseAddress = 0x1000000;
BiosMemoryMap[EntryCount].Length = ExtendedMemorySizeAtSixteenMB * 64 * 1024;
BiosMemoryMap[EntryCount].Type = BiosMemoryUsable;
EntryCount++;
}
} }
return EntryCount; return EntryCount;