diff options
Diffstat (limited to 'MdeModulePkg/Universal/DebugSupportDxe/Ia32/PlDebugSupport.c')
-rw-r--r-- | MdeModulePkg/Universal/DebugSupportDxe/Ia32/PlDebugSupport.c | 20 |
1 files changed, 19 insertions, 1 deletions
diff --git a/MdeModulePkg/Universal/DebugSupportDxe/Ia32/PlDebugSupport.c b/MdeModulePkg/Universal/DebugSupportDxe/Ia32/PlDebugSupport.c index 3c96f9b..ed38d06 100644 --- a/MdeModulePkg/Universal/DebugSupportDxe/Ia32/PlDebugSupport.c +++ b/MdeModulePkg/Universal/DebugSupportDxe/Ia32/PlDebugSupport.c @@ -1,5 +1,5 @@ /** @file
- Generic debug support functions for IA32/x64.
+ IA32/x64 generic functions to support Debug Support protocol.
Copyright (c) 2006 - 2008, Intel Corporation
All rights reserved. This program and the accompanying materials
@@ -90,11 +90,27 @@ HookEntry ( //
OldIntFlagState = SaveAndDisableInterrupts ();
+ //
+ // gets IDT Gate descriptor by index
+ //
ReadIdtGateDescriptor (ExceptionType, &(IdtEntryTable[ExceptionType].OrigDesc));
+ //
+ // stores orignal interrupt handle
+ //
IdtEntryTable[ExceptionType].OrigVector = (DEBUG_PROC) GetInterruptHandleFromIdt (&(IdtEntryTable[ExceptionType].OrigDesc));
+ //
+ // encodes new IDT Gate descriptor by stub entry
+ //
Vect2Desc (&IdtEntryTable[ExceptionType].NewDesc, IdtEntryTable[ExceptionType].StubEntry);
+ //
+ // stores NewCallback
+ //
IdtEntryTable[ExceptionType].RegisteredCallback = NewCallback;
+
+ //
+ // writes back new IDT Gate descriptor
+ //
WriteIdtGateDescriptor (ExceptionType, &(IdtEntryTable[ExceptionType].NewDesc));
//
@@ -214,6 +230,7 @@ RegisterExceptionCallback ( return ManageIdtEntryTable (ExceptionCallback, ExceptionType);
}
+
/**
Invalidates processor instruction cache for a memory range. Subsequent execution in this range
causes a fresh memory fetch to retrieve code to be executed.
@@ -244,6 +261,7 @@ InvalidateInstructionCache ( Common piece of code that invokes the registered handlers.
This code executes in exception context so no efi calls are allowed.
+ This code is called from assembly file.
@param ExceptionType Exception type
@param ContextRecord System context
|