PlDebugSupport.c revision 4fd606d1f5abe38e1f42c38de1d2e895166bd0f4
/** @file
Copyright (c) 2006 - 2010, Intel Corporation. All rights reserved.<BR>
This program and the accompanying materials
are licensed and made available under the terms and conditions of the BSD License
which accompanies this distribution. The full text of the license may be found at
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
**/
#include "DebugSupport.h"
//
// This the global main table to keep track of the interrupts
//
/**
Read IDT Gate Descriptor from IDT Table.
@param Vector Specifies vector number.
@param IdtGateDescriptor Pointer to IDT Gate Descriptor read from IDT Table.
**/
)
{
AsmReadIdtr (&IdtrValue);
CopyMem ((VOID *) IdtGateDescriptor, (VOID *) &(IdtTable)[Vector], sizeof (IA32_IDT_GATE_DESCRIPTOR));
}
/**
Write IDT Gate Descriptor into IDT Table.
@param Vector Specifies vector number.
@param IdtGateDescriptor Pointer to IDT Gate Descriptor written into IDT Table.
**/
)
{
AsmReadIdtr (&IdtrValue);
CopyMem ((VOID *) &(IdtTable)[Vector], (VOID *) IdtGateDescriptor, sizeof (IA32_IDT_GATE_DESCRIPTOR));
}
/**
Creates a nes entry stub. Then saves the current IDT entry and replaces it
with an interrupt gate for the new entry point. The IdtEntryTable is updated
with the new registered function.
This code executes in boot services context. The stub entry executes in interrupt
context.
@param ExceptionType Specifies which vector to hook.
@param NewCallback A pointer to the new function to be registered.
**/
)
{
//
// Disables CPU interrupts and returns the previous interrupt state
//
//
// gets IDT Gate descriptor by index
//
//
// stores orignal interrupt handle
//
IdtEntryTable[ExceptionType].OrigVector = (DEBUG_PROC) GetInterruptHandleFromIdt (&(IdtEntryTable[ExceptionType].OrigDesc));
//
// encodes new IDT Gate descriptor by stub entry
//
//
// stores NewCallback
//
//
// writes back new IDT Gate descriptor
//
//
// restore interrupt state
//
return ;
}
/**
Undoes HookEntry. This code executes in boot services context.
@param ExceptionType Specifies which entry to unhook
**/
)
{
//
// Disables CPU interrupts and returns the previous interrupt state
//
//
// restore the default IDT Date Descriptor
//
//
// restore interrupt state
//
return ;
}
/**
Returns the maximum value that may be used for the ProcessorIndex parameter in
RegisterPeriodicCallback() and RegisterExceptionCallback().
Hard coded to support only 1 processor for now.
@param This A pointer to the EFI_DEBUG_SUPPORT_PROTOCOL instance.
@param MaxProcessorIndex Pointer to a caller-allocated UINTN in which the maximum supported
processor index is returned. Always 0 returned.
@retval EFI_SUCCESS Always returned with **MaxProcessorIndex set to 0.
**/
)
{
*MaxProcessorIndex = 0;
return EFI_SUCCESS;
}
/**
Registers a function to be called back periodically in interrupt context.
@param This A pointer to the EFI_DEBUG_SUPPORT_PROTOCOL instance.
@param ProcessorIndex Specifies which processor the callback function applies to.
@param PeriodicCallback A pointer to a function of type PERIODIC_CALLBACK that is the main
periodic entry point of the debug agent.
@retval EFI_SUCCESS The function completed successfully.
@retval EFI_ALREADY_STARTED Non-NULL PeriodicCallback parameter when a callback
function was previously registered.
@retval EFI_OUT_OF_RESOURCES System has insufficient memory resources to register new callback
function.
**/
)
{
}
/**
Registers a function to be called when a given processor exception occurs.
This code executes in boot services context.
@param This A pointer to the EFI_DEBUG_SUPPORT_PROTOCOL instance.
@param ProcessorIndex Specifies which processor the callback function applies to.
@param ExceptionCallback A pointer to a function of type EXCEPTION_CALLBACK that is called
when the processor exception specified by ExceptionType occurs.
@param ExceptionType Specifies which processor exception to hook.
@retval EFI_SUCCESS The function completed successfully.
@retval EFI_ALREADY_STARTED Non-NULL PeriodicCallback parameter when a callback
function was previously registered.
@retval EFI_OUT_OF_RESOURCES System has insufficient memory resources to register new callback
function.
**/
)
{
}
/**
Invalidates processor instruction cache for a memory range. Subsequent execution in this range
causes a fresh memory fetch to retrieve code to be executed.
@param This A pointer to the EFI_DEBUG_SUPPORT_PROTOCOL instance.
@param ProcessorIndex Specifies which processor's instruction cache is to be invalidated.
@param Start Specifies the physical base of the memory range to be invalidated.
@param Length Specifies the minimum number of bytes in the processor's instruction
cache to invalidate.
@retval EFI_SUCCESS Always returned.
**/
)
{
AsmWbinvd ();
return EFI_SUCCESS;
}
/**
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
**/
)
{
if (ExceptionType != SYSTEM_TIMER_VECTOR) {
} else {
}
}
}
/**
This is the callback that is written to the Loaded Image protocol instance
on the image handle. It uninstalls all registered handlers and frees all entry
stub memory.
@param ImageHandle The firmware allocated handle for the EFI image.
@retval EFI_SUCCESS Always.
**/
)
{
//
// Free space for each Interrupt Stub precedure.
//
}
}
return EFI_SUCCESS;
}
/**
Initializes driver's handler registration database.
This code executes in boot services context.
Must be public because it's referenced from DebugSupport.c
the context save will fail, so these processors are not supported.
@retval EFI_OUT_OF_RESOURCES Fails to allocate memory.
@retval EFI_SUCCESS Initializes successfully.
**/
)
{
//
// Check whether FxStor instructions are supported.
//
if (!FxStorSupport ()) {
return EFI_UNSUPPORTED;
}
if (IdtEntryTable == NULL) {
return EFI_OUT_OF_RESOURCES;
}
goto ErrorCleanup;
}
//
// Copy Interrupt stub code.
//
}
return EFI_SUCCESS;
}
}
return EFI_OUT_OF_RESOURCES;
}