audk/SourceLevelDebugPkg/Library/DebugAgent/SmmDebugAgent/SmmDebugAgentLib.c

155 lines
4.1 KiB
C

/** @file
Debug Agent library implementition.
Copyright (c) 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
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 "SmmDebugAgentLib.h"
DEBUG_AGENT_MAILBOX *mMailboxPointer = NULL;
DEBUG_AGENT_MAILBOX mLocalMailbox;
UINTN mSavedDebugRegisters[6];
CONST BOOLEAN MultiProcessorDebugSupport = FALSE;
/**
Get Debug Agent Mailbox pointer.
@return Mailbox pointer.
**/
DEBUG_AGENT_MAILBOX *
GetMailboxPointer (
VOID
)
{
return mMailboxPointer;
}
/**
Get debug port handle.
@return Debug port handle.
**/
DEBUG_PORT_HANDLE
GetDebugPortHandle (
VOID
)
{
return (DEBUG_PORT_HANDLE) (UINTN)(mMailboxPointer->DebugPortHandle);
}
/**
Store debug register when SMI exit.
**/
VOID
SaveDebugRegister (
VOID
)
{
mSavedDebugRegisters[0] = AsmReadDr0 ();
mSavedDebugRegisters[1] = AsmReadDr1 ();
mSavedDebugRegisters[2] = AsmReadDr2 ();
mSavedDebugRegisters[3] = AsmReadDr3 ();
mSavedDebugRegisters[4] = AsmReadDr6 ();
mSavedDebugRegisters[5] = AsmReadDr7 ();
}
/**
Restore debug register when SMI exit.
**/
VOID
RestoreDebugRegister (
VOID
)
{
AsmWriteDr7 (0);
AsmWriteDr0 (mSavedDebugRegisters[0]);
AsmWriteDr1 (mSavedDebugRegisters[1]);
AsmWriteDr2 (mSavedDebugRegisters[2]);
AsmWriteDr3 (mSavedDebugRegisters[3]);
AsmWriteDr6 (mSavedDebugRegisters[4]);
AsmWriteDr7 (mSavedDebugRegisters[5]);
}
/**
Initialize debug agent.
This function is used to set up debug enviroment for source level debug
in SMM code.
If InitFlag is DEBUG_AGENT_INIT_SMM, it will overirde IDT table entries
and initialize debug port. It will get debug agent Mailbox from GUIDed HOB,
it it exists, debug agent wiil copied it into the local Mailbox in SMM space.
it will overirde IDT table entries and initialize debug port. Context will be
NULL.
If InitFlag is DEBUG_AGENT_INIT_ENTER_SMI, debug agent will save Debug
Registers and get local Mailbox in SMM space. Context will be NULL.
If InitFlag is DEBUG_AGENT_INIT_EXIT_SMI, debug agent will restore Debug
Registers. Context will be NULL.
@param[in] InitFlag Init flag is used to decide initialize process.
@param[in] Context Context needed according to InitFlag.
@param[in] Function Continue function called by debug agent library; it was
optional.
**/
VOID
EFIAPI
InitializeDebugAgent (
IN UINT32 InitFlag,
IN VOID *Context, OPTIONAL
IN DEBUG_AGENT_CONTINUE Function OPTIONAL
)
{
EFI_STATUS Status;
UINT64 DebugPortHandle;
switch (InitFlag) {
case DEBUG_AGENT_INIT_SMM:
Status = EfiGetSystemConfigurationTable (&gEfiDebugAgentGuid, (VOID **) &mMailboxPointer);
if (EFI_ERROR (Status) || mMailboxPointer == NULL) {
ZeroMem (&mLocalMailbox, sizeof (DEBUG_AGENT_MAILBOX));
mMailboxPointer = &mLocalMailbox;
}
break;
case DEBUG_AGENT_INIT_ENTER_SMI:
SaveDebugRegister ();
InitializeDebugIdt ();
if (mMailboxPointer != NULL) {
//
// Initialize debug communication port
//
DebugPortHandle = (UINT64) (UINTN)DebugPortInitialize ((DEBUG_PORT_HANDLE) (UINTN)mMailboxPointer->DebugPortHandle, NULL);
mMailboxPointer->DebugPortHandle = DebugPortHandle;
if (mMailboxPointer->DebugFlag.Bits.BreakOnNextSmi == 1) {
//
// If SMM entry break is set, SMM code will be break at here.
//
CpuBreakpoint ();
}
}
break;
case DEBUG_AGENT_INIT_EXIT_SMI:
RestoreDebugRegister ();
break;
}
}