mirror of https://github.com/acidanthera/audk.git
146 lines
4.4 KiB
C
146 lines
4.4 KiB
C
/** @file
|
|
IA32 specific functions to support Debug Support protocol.
|
|
|
|
Copyright (c) 2008, Intel Corporation
|
|
All rights reserved. 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
|
|
http://opensource.org/licenses/bsd-license.php
|
|
|
|
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 "PlDebugSupport.h"
|
|
|
|
IA32_IDT_GATE_DESCRIPTOR NullDesc = {{0}};
|
|
|
|
/**
|
|
Get Interrupt Handle from IDT Gate Descriptor.
|
|
|
|
@param IdtGateDescriptor IDT Gate Descriptor.
|
|
|
|
@return Interrupt Handle stored in IDT Gate Descriptor.
|
|
|
|
**/
|
|
UINTN
|
|
GetInterruptHandleFromIdt (
|
|
IN IA32_IDT_GATE_DESCRIPTOR *IdtGateDescriptor
|
|
)
|
|
{
|
|
UINTN InterruptHandle;
|
|
|
|
//
|
|
// InterruptHandle 0-15 : OffsetLow
|
|
// InterruptHandle 16-31 : OffsetHigh
|
|
//
|
|
((UINT16 *) &InterruptHandle)[0] = (UINT16) IdtGateDescriptor->Bits.OffsetLow;
|
|
((UINT16 *) &InterruptHandle)[1] = (UINT16) IdtGateDescriptor->Bits.OffsetHigh;
|
|
|
|
return InterruptHandle;
|
|
}
|
|
|
|
/**
|
|
Allocate pool for a new IDT entry stub.
|
|
|
|
Copy the generic stub into the new buffer and fixup the vector number
|
|
and jump target address.
|
|
|
|
@param ExceptionType This is the exception type that the new stub will be created
|
|
for.
|
|
@param Stub On successful exit, *Stub contains the newly allocated entry stub.
|
|
|
|
**/
|
|
VOID
|
|
CreateEntryStub (
|
|
IN EFI_EXCEPTION_TYPE ExceptionType,
|
|
OUT VOID **Stub
|
|
)
|
|
{
|
|
UINT8 *StubCopy;
|
|
|
|
StubCopy = *Stub;
|
|
|
|
//
|
|
// Fixup the stub code for this vector
|
|
//
|
|
|
|
// The stub code looks like this:
|
|
//
|
|
// 00000000 89 25 00000004 R mov AppEsp, esp ; save stack top
|
|
// 00000006 BC 00008014 R mov esp, offset DbgStkBot ; switch to debugger stack
|
|
// 0000000B 6A 00 push 0 ; push vector number - will be modified before installed
|
|
// 0000000D E9 db 0e9h ; jump rel32
|
|
// 0000000E 00000000 dd 0 ; fixed up to relative address of CommonIdtEntry
|
|
//
|
|
|
|
//
|
|
// poke in the exception type so the second push pushes the exception type
|
|
//
|
|
StubCopy[0x0c] = (UINT8) ExceptionType;
|
|
|
|
//
|
|
// fixup the jump target to point to the common entry
|
|
//
|
|
*(UINT32 *) &StubCopy[0x0e] = (UINT32) CommonIdtEntry - (UINT32) &StubCopy[StubSize];
|
|
|
|
return ;
|
|
}
|
|
|
|
/**
|
|
This is the main worker function that manages the state of the interrupt
|
|
handlers. It both installs and uninstalls interrupt handlers based on the
|
|
value of NewCallback. If NewCallback is NULL, then uninstall is indicated.
|
|
If NewCallback is non-NULL, then install is indicated.
|
|
|
|
@param NewCallback If non-NULL, NewCallback specifies the new handler to register.
|
|
If NULL, specifies that the previously registered handler should
|
|
be uninstalled.
|
|
@param ExceptionType Indicates which entry to manage.
|
|
|
|
@retval EFI_SUCCESS Installing or Uninstalling operation is ok.
|
|
@retval EFI_INVALID_PARAMETER Requested uninstalling a handler from a vector that has
|
|
no handler registered for it
|
|
@retval EFI_ALREADY_STARTED Requested install to a vector that already has a handler registered.
|
|
|
|
**/
|
|
EFI_STATUS
|
|
ManageIdtEntryTable (
|
|
VOID (*NewCallback)(),
|
|
EFI_EXCEPTION_TYPE ExceptionType
|
|
)
|
|
{
|
|
EFI_STATUS Status;
|
|
|
|
Status = EFI_SUCCESS;
|
|
|
|
if (CompareMem (&IdtEntryTable[ExceptionType].NewDesc, &NullDesc, sizeof (IA32_IDT_GATE_DESCRIPTOR)) != 0) {
|
|
//
|
|
// we've already installed to this vector
|
|
//
|
|
if (NewCallback != NULL) {
|
|
//
|
|
// if the input handler is non-null, error
|
|
//
|
|
Status = EFI_ALREADY_STARTED;
|
|
} else {
|
|
UnhookEntry (ExceptionType);
|
|
}
|
|
} else {
|
|
//
|
|
// no user handler installed on this vector
|
|
//
|
|
if (NewCallback == NULL) {
|
|
//
|
|
// if the input handler is null, error
|
|
//
|
|
Status = EFI_INVALID_PARAMETER;
|
|
} else {
|
|
HookEntry (ExceptionType, NewCallback);
|
|
}
|
|
}
|
|
|
|
return Status;
|
|
}
|