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|
DefinitionBlock (
"AcpiDebug.aml",
"SSDT",
1,
"Intel_",
"ADebTabl",
0x1000
)
{
Scope(\)
{
//
// These pointers are patched during POST.
//
Name(DPTR, 0x80000000) // Address of Acpi debug memory buffer, fixed up during POST
Name(EPTR, 0x80000000) // End of Acpi debug memory buffer, fixed up during POST
Name(CPTR, 0x80000000) // Current pointer used as an index into the buffer(starts after the buffer signature), fixed up during POST
//
//Use a Mutex to prevent multiple calls from simutaneously writing to the same memory.
//
Mutex(MMUT, 0)
//
// Write a string to a memory buffer
//
Method(MDBG,1,Serialized)
{
Store (Acquire(MMUT, 1000),Local0) // save Acquire result so we can check for Mutex acquired
If (LEqual(Local0, Zero)) // check for Mutex acquired
{
OperationRegion(ABLK, SystemMemory, CPTR, 16) // Operation region to allow writes to ACPI debug buffer
Field(ABLK, ByteAcc, NoLock, Preserve)
{
Offset(0x0),
AAAA, 128 // 16 byte string or data
}
Store(Arg0,AAAA) // anything past string buffer size is ignored by ACPI
Add(CPTR,16,CPTR) // advance current pointer to next string location in memory buffer
If (LGreaterEqual(CPTR,EPTR) ) // check for end of 64kb Acpi debug buffer
{
Add(DPTR,16,CPTR) // wrap around to beginning of buffer if the end has been reached
}
Release(MMUT)
}
Return(Local0) // return error code indicating whether Mutex was acquired
}
} // End Scope
} // End SSDT
|
