/** @file
IPF specific functions to support Debug Support protocol.
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
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"
BOOLEAN mInHandler = FALSE;
//
// number of bundles to swap in ivt
//
#define NUM_BUNDLES_IN_STUB 5
#define NUM_IVT_ENTRIES 64
typedef struct {
BUNDLE OrigBundles[NUM_BUNDLES_IN_STUB];
CALLBACK_FUNC RegisteredCallback;
} IVT_ENTRY;
IVT_ENTRY IvtEntryTable[NUM_IVT_ENTRIES];
//
// IPF context record is overallocated by 512 bytes to guarantee a 512 byte alignment exists
// within the buffer and still have a large enough buffer to hold a whole IPF context record.
//
UINT8 IpfContextBuf[sizeof (EFI_SYSTEM_CONTEXT_IPF) + 512];
//
// The PatchSaveBuffer is used to store the original bundles from the IVT where it is patched
// with the common handler.
//
UINT8 PatchSaveBuffer[0x400];
UINTN ExternalInterruptCount;
/**
IPF specific DebugSupport driver initialization.
Must be public because it's referenced from DebugSupport.c
@retval EFI_SUCCESS Always.
**/
EFI_STATUS
PlInitializeDebugSupportDriver (
VOID
)
{
ZeroMem (IvtEntryTable, sizeof (IvtEntryTable));
ExternalInterruptCount = 0;
return EFI_SUCCESS;
}
/**
Unload handler that is called during UnloadImage() - deallocates pool memory
used by the driver.
Must be public because it's referenced from DebugSuport.c
@param ImageHandle The firmware allocated handle for the EFI image.
@retval EFI_SUCCESS Always.
**/
EFI_STATUS
EFIAPI
PlUnloadDebugSupportDriver (
IN EFI_HANDLE ImageHandle
)
{
EFI_EXCEPTION_TYPE ExceptionType;
for (ExceptionType = 0; ExceptionType < NUM_IVT_ENTRIES; ExceptionType++) {
ManageIvtEntryTable (ExceptionType, NULL, NULL);
}
return EFI_SUCCESS;
}
/**
C routine that is called for all registered exceptions. This is the main
exception dispatcher.
Must be public because it's referenced from AsmFuncs.s.
@param ExceptionType Specifies which processor exception.
@param Context System Context.
**/
VOID
CommonHandler (
IN EFI_EXCEPTION_TYPE ExceptionType,
IN EFI_SYSTEM_CONTEXT Context
)
{
DEBUG_CODE_BEGIN ();
if (mInHandler) {
DEBUG ((EFI_D_INFO, "ERROR: Re-entered debugger!\n"
" ExceptionType == %X\n"
" Context == %X\n"
" Context.SystemContextIpf->CrIip == %LX\n"
" Context.SystemContextIpf->CrIpsr == %LX\n"
" mInHandler == %X\n",
(INT32)ExceptionType,
Context,
Context.SystemContextIpf->CrIip,
Context.SystemContextIpf->CrIpsr,
mInHandler));
}
DEBUG_CODE_END ();
ASSERT (!mInHandler);
mInHandler = TRUE;
if (IvtEntryTable[ExceptionType].RegisteredCallback != NULL) {
if (ExceptionType != EXCEPT_IPF_EXTERNAL_INTERRUPT) {
IvtEntryTable[ExceptionType].RegisteredCallback (ExceptionType, Context.SystemContextIpf);
} else {
IvtEntryTable[ExceptionType].RegisteredCallback (Context.SystemContextIpf);
}
} else {
ASSERT (0);
}
mInHandler = FALSE;
}
/**
Given an integer number, return the physical address of the entry point in the IFT.
@param HandlerIndex Index of the Handler
@param EntryPoint IFT Entrypoint
**/
VOID
GetHandlerEntryPoint (
UINTN HandlerIndex,
VOID **EntryPoint
)
{
UINT8 *TempPtr;
//
// get base address of IVT
//
TempPtr = GetIva ();
if (HandlerIndex < 20) {
//
// first 20 provide 64 bundles per vector
//
TempPtr += 0x400 * HandlerIndex;
} else {
//
// the rest provide 16 bundles per vector
//
TempPtr += 0x5000 + 0x100 * (HandlerIndex - 20);
}
*EntryPoint = (VOID *) TempPtr;
}
/**
This is the worker function that uninstalls and removes all handlers.
@param ExceptionType Specifies which processor exception.
@param NewBundles New Boundles.
@param NewCallback A pointer to the new function to be registered.
@retval EFI_ALEADY_STARTED Ivt already hooked.
@retval EFI_SUCCESS Successfully uninstalled.
**/
EFI_STATUS
ManageIvtEntryTable (
IN EFI_EXCEPTION_TYPE ExceptionType,
IN BUNDLE NewBundles[NUM_BUNDLES_IN_STUB],
IN CALLBACK_FUNC NewCallback
)
{
BUNDLE *B0Ptr;
UINT64 InterruptFlags;
EFI_TPL OldTpl;
//
// Get address of bundle 0
//
GetHandlerEntryPoint (ExceptionType, (VOID **) &B0Ptr);
if (IvtEntryTable[ExceptionType].RegisteredCallback != NULL) {
//
// we've already installed to this vector
//
if (NewCallback != NULL) {
//
// if the input handler is non-null, error
//
return EFI_ALREADY_STARTED;
} else {
//
// else remove the previously installed handler
//
OldTpl = gBS->RaiseTPL (TPL_HIGH_LEVEL);
InterruptFlags = ProgramInterruptFlags (DISABLE_INTERRUPTS);
if (ExceptionType == EXCEPT_IPF_EXTERNAL_INTERRUPT) {
UnchainExternalInterrupt ();
} else {
UnhookEntry (ExceptionType);
}
ProgramInterruptFlags (InterruptFlags);
gBS->RestoreTPL (OldTpl);
//
// re-init IvtEntryTable
//
ZeroMem (&IvtEntryTable[ExceptionType], sizeof (IVT_ENTRY));
}
} else {
//
// no user handler installed on this vector
//
if (NewCallback != NULL) {
OldTpl = gBS->RaiseTPL (TPL_HIGH_LEVEL);
InterruptFlags = ProgramInterruptFlags (DISABLE_INTERRUPTS);
if (ExceptionType == EXCEPT_IPF_EXTERNAL_INTERRUPT) {
ChainExternalInterrupt (NewCallback);
} else {
HookEntry (ExceptionType, NewBundles, NewCallback);
}
ProgramInterruptFlags (InterruptFlags);
gBS->RestoreTPL (OldTpl);
}
}
return EFI_SUCCESS;
}
/**
Saves original IVT contents and inserts a few new bundles which are fixed up
to store the ExceptionType and then call the common handler.
@param ExceptionType Specifies which processor exception.
@param NewBundles New Boundles.
@param NewCallback A pointer to the new function to be hooked.
**/
VOID
HookEntry (
IN EFI_EXCEPTION_TYPE ExceptionType,
IN BUNDLE NewBundles[4],
IN CALLBACK_FUNC NewCallback
)
{
BUNDLE *FixupBundle;
BUNDLE *B0Ptr;
//
// Get address of bundle 0
//
GetHandlerEntryPoint (ExceptionType, (VOID **) &B0Ptr);
//
// copy original bundles from IVT to IvtEntryTable so we can restore them later
//
CopyMem (
IvtEntryTable[ExceptionType].OrigBundles,
B0Ptr,
sizeof (BUNDLE) * NUM_BUNDLES_IN_STUB
);
//
// insert new B0
//
CopyMem (B0Ptr, NewBundles, sizeof (BUNDLE) * NUM_BUNDLES_IN_STUB);
//
// fixup IVT entry so it stores its index and whether or not to chain...
//
FixupBundle = B0Ptr + 2;
FixupBundle->High |= ExceptionType << 36;
InstructionCacheFlush (B0Ptr, 5);
IvtEntryTable[ExceptionType].RegisteredCallback = NewCallback;
}
/**
Restores original IVT contents when unregistering a callback function.
@param ExceptionType Specifies which processor exception.
**/
VOID
UnhookEntry (
IN EFI_EXCEPTION_TYPE ExceptionType
)
{
BUNDLE *B0Ptr;
//
// Get address of bundle 0
//
GetHandlerEntryPoint (ExceptionType, (VOID **) &B0Ptr);
//
// restore original bundles in IVT
//
CopyMem (
B0Ptr,
IvtEntryTable[ExceptionType].OrigBundles,
sizeof (BUNDLE) * NUM_BUNDLES_IN_STUB
);
InstructionCacheFlush (B0Ptr, 5);
}
/**
Sets up cache flush and calls assembly function to chain external interrupt.
Records new callback in IvtEntryTable.
@param NewCallback A pointer to the interrupt handle.
**/
VOID
ChainExternalInterrupt (
IN CALLBACK_FUNC NewCallback
)
{
VOID *Start;
Start = (VOID *) ((UINT8 *) GetIva () + 0x400 * EXCEPT_IPF_EXTERNAL_INTERRUPT + 0x400);
IvtEntryTable[EXCEPT_IPF_EXTERNAL_INTERRUPT].RegisteredCallback = NewCallback;
ChainHandler ();
InstructionCacheFlush (Start, 0x400);
}
/**
Sets up cache flush and calls assembly function to restore external interrupt.
Removes registered callback from IvtEntryTable.
**/
VOID
UnchainExternalInterrupt (
VOID
)
{
VOID *Start;
Start = (VOID *) ((UINT8 *) GetIva () + 0x400 * EXCEPT_IPF_EXTERNAL_INTERRUPT + 0x400);
UnchainHandler ();
InstructionCacheFlush (Start, 0x400);
IvtEntryTable[EXCEPT_IPF_EXTERNAL_INTERRUPT].RegisteredCallback = NULL;
}
/**
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.
**/
EFI_STATUS
EFIAPI
GetMaximumProcessorIndex (
IN EFI_DEBUG_SUPPORT_PROTOCOL *This,
OUT UINTN *MaxProcessorIndex
)
{
*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.
**/
EFI_STATUS
EFIAPI
RegisterPeriodicCallback (
IN EFI_DEBUG_SUPPORT_PROTOCOL *This,
IN UINTN ProcessorIndex,
IN EFI_PERIODIC_CALLBACK PeriodicCallback
)
{
return ManageIvtEntryTable (EXCEPT_IPF_EXTERNAL_INTERRUPT, NULL, PeriodicCallback);
}
/**
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.
**/
EFI_STATUS
EFIAPI
RegisterExceptionCallback (
IN EFI_DEBUG_SUPPORT_PROTOCOL *This,
IN UINTN ProcessorIndex,
IN EFI_EXCEPTION_CALLBACK ExceptionCallback,
IN EFI_EXCEPTION_TYPE ExceptionType
)
{
return ManageIvtEntryTable (
ExceptionType,
(BUNDLE *) ((EFI_PLABEL *) HookStub)->EntryPoint,
ExceptionCallback
);
}
/**
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.
**/
EFI_STATUS
EFIAPI
InvalidateInstructionCache (
IN EFI_DEBUG_SUPPORT_PROTOCOL *This,
IN UINTN ProcessorIndex,
IN VOID *Start,
IN UINTN Length
)
{
InstructionCacheFlush (Start, Length);
return EFI_SUCCESS;
}