[mirror_edk2.git] / MdeModulePkg / Universal / DebugSupportDxe / X64 / PlDebugSupport.c

/** @file\r
  X64 specific debug support functions\r
\r
Copyright (c) 2006 - 2007, Intel Corporation\r
All rights reserved. This program and the accompanying materials\r
are licensed and made available under the terms and conditions of the BSD License\r
which accompanies this distribution.  The full text of the license may be found at\r
http://opensource.org/licenses/bsd-license.php\r
\r
THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
\r
**/\r
\r
//\r
// private header files\r
//\r
#include "PlDebugSupport.h"\r
\r
//\r
// This the global main table to keep track of the interrupts\r
//\r
IDT_ENTRY   *IdtEntryTable  = NULL;\r
DESCRIPTOR  NullDesc        = {0, 0};\r
\r
/**\r
  Allocate pool for a new IDT entry stub.\r
\r
  Copy the generic stub into the new buffer and fixup the vector number\r
  and jump target address.\r
\r
  @param  ExceptionType   This is the exception type that the new stub will be created\r
                          for.\r
  @param  Stub            On successful exit, *Stub contains the newly allocated entry stub.\r
\r
  @retval EFI_SUCCESS     Always.\r
\r
**/\r
EFI_STATUS\r
CreateEntryStub (\r
  IN EFI_EXCEPTION_TYPE     ExceptionType,\r
  OUT VOID                  **Stub\r
  )\r
{\r
  UINT8       *StubCopy;\r
\r
  StubCopy = *Stub;\r
\r
  //\r
  // Fixup the stub code for this vector\r
  //\r
\r
  // The stub code looks like this:\r
  //\r
  //    00000000  6A 00               push    0                       ; push vector number - will be modified before installed\r
  //    00000002  E9                  db      0e9h                    ; jump rel32\r
  //    00000003  00000000            dd      0                       ; fixed up to relative address of CommonIdtEntry\r
  //\r
\r
  //\r
  // poke in the exception type so the second push pushes the exception type\r
  //\r
  StubCopy[0x1] = (UINT8) ExceptionType;\r
\r
  //\r
  // fixup the jump target to point to the common entry\r
  //\r
  *(UINT32 *) &StubCopy[0x3] = (UINT32)((UINTN) CommonIdtEntry - (UINTN) &StubCopy[StubSize]);\r
\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  Creates a nes entry stub.  Then saves the current IDT entry and replaces it\r
  with an interrupt gate for the new entry point.  The IdtEntryTable is updated\r
  with the new registered function.\r
\r
  This code executes in boot services context.  The stub entry executes in interrupt\r
  context.\r
\r
  @param  ExceptionType      Specifies which vector to hook.\r
  @param  NewCallback        A pointer to the new function to be registered.\r
\r
  @retval EFI_SUCCESS        Always.\r
\r
**/\r
EFI_STATUS\r
HookEntry (\r
  IN EFI_EXCEPTION_TYPE            ExceptionType,\r
  IN VOID                         (*NewCallback) ()\r
  )\r
{\r
  BOOLEAN     OldIntFlagState;\r
  EFI_STATUS  Status;\r
\r
  Status = CreateEntryStub (ExceptionType, (VOID **) &IdtEntryTable[ExceptionType].StubEntry);\r
  if (Status == EFI_SUCCESS) {\r
    OldIntFlagState = WriteInterruptFlag (0);\r
    READ_IDT (ExceptionType, &(IdtEntryTable[ExceptionType].OrigDesc));\r
\r
    ((UINT16 *) &IdtEntryTable[ExceptionType].OrigVector)[0]  = ((UINT16 *) &IdtEntryTable[ExceptionType].OrigDesc.Low)[0];\r
    ((UINT16 *) &IdtEntryTable[ExceptionType].OrigVector)[1]  = ((UINT16 *) &IdtEntryTable[ExceptionType].OrigDesc.Low)[3];\r
    ((UINT32 *) &IdtEntryTable[ExceptionType].OrigVector)[1]  = ((UINT32 *) &IdtEntryTable[ExceptionType].OrigDesc.High)[0];\r
\r
    Vect2Desc (&IdtEntryTable[ExceptionType].NewDesc, IdtEntryTable[ExceptionType].StubEntry);\r
    IdtEntryTable[ExceptionType].RegisteredCallback = NewCallback;\r
    WRITE_IDT (ExceptionType, &(IdtEntryTable[ExceptionType].NewDesc));\r
    WriteInterruptFlag (OldIntFlagState);\r
  }\r
\r
  return Status;\r
}\r
\r
/**\r
  Undoes HookEntry. This code executes in boot services context.\r
\r
  @param  ExceptionType   Specifies which entry to unhook\r
\r
  @retval EFI_SUCCESS     Always.\r
\r
**/\r
EFI_STATUS\r
UnhookEntry (\r
  IN EFI_EXCEPTION_TYPE           ExceptionType\r
  )\r
{\r
  BOOLEAN     OldIntFlagState;\r
\r
  OldIntFlagState = WriteInterruptFlag (0);\r
  WRITE_IDT (ExceptionType, &(IdtEntryTable[ExceptionType].OrigDesc));\r
  WriteInterruptFlag (OldIntFlagState);\r
\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  This is the main worker function that manages the state of the interrupt\r
  handlers.  It both installs and uninstalls interrupt handlers based on the\r
  value of NewCallback.  If NewCallback is NULL, then uninstall is indicated.\r
  If NewCallback is non-NULL, then install is indicated.\r
\r
  @param  NewCallback   If non-NULL, NewCallback specifies the new handler to register.\r
                        If NULL, specifies that the previously registered handler should\r
                        be uninstalled.\r
  @param  ExceptionType Indicates which entry to manage.\r
\r
  @retval EFI_SUCCESS            Process is ok.\r
  @retval EFI_INVALID_PARAMETER  Requested uninstalling a handler from a vector that has\r
                                 no handler registered for it\r
  @retval EFI_ALREADY_STARTED    Requested install to a vector that already has a handler registered.\r
  @retval others                 Possible return values are passed through from UnHookEntry and HookEntry.\r
\r
**/\r
EFI_STATUS\r
ManageIdtEntryTable (\r
  VOID (*NewCallback)(),\r
  EFI_EXCEPTION_TYPE ExceptionType\r
  )\r
{\r
  EFI_STATUS  Status;\r
\r
  Status = EFI_SUCCESS;\r
\r
  if (COMPARE_DESCRIPTOR (&IdtEntryTable[ExceptionType].NewDesc, &NullDesc)) {\r
    //\r
    // we've already installed to this vector\r
    //\r
    if (NewCallback != NULL) {\r
      //\r
      // if the input handler is non-null, error\r
      //\r
      Status = EFI_ALREADY_STARTED;\r
    } else {\r
      Status = UnhookEntry (ExceptionType);\r
    }\r
  } else {\r
    //\r
    // no user handler installed on this vector\r
    //\r
    if (NewCallback == NULL) {\r
      //\r
      // if the input handler is null, error\r
      //\r
      Status = EFI_INVALID_PARAMETER;\r
    } else {\r
      Status = HookEntry (ExceptionType, NewCallback);\r
    }\r
  }\r
\r
  return Status;\r
}\r
\r
/**\r
  This is a DebugSupport protocol member function, hard\r
  coded to support only 1 processor for now.\r
\r
  @param  This                The DebugSupport instance\r
  @param  MaxProcessorIndex   The maximuim supported processor index\r
\r
  @retval EFI_SUCCESS         Always returned with **MaxProcessorIndex set to 0.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
GetMaximumProcessorIndex (\r
  IN EFI_DEBUG_SUPPORT_PROTOCOL       *This,\r
  OUT UINTN                           *MaxProcessorIndex\r
  )\r
{\r
  *MaxProcessorIndex = 0;\r
  return (EFI_SUCCESS);\r
}\r
\r
/**\r
  DebugSupport protocol member function.\r
\r
  @param  This               The DebugSupport instance\r
  @param  ProcessorIndex     Which processor the callback applies to.\r
  @param  PeriodicCallback   Callback function\r
\r
  @retval EFI_SUCCESS        Indicates the callback was registered.\r
  @retval others             Callback was not registered.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
RegisterPeriodicCallback (\r
  IN EFI_DEBUG_SUPPORT_PROTOCOL *This,\r
  IN UINTN                      ProcessorIndex,\r
  IN EFI_PERIODIC_CALLBACK      PeriodicCallback\r
  )\r
{\r
  return ManageIdtEntryTable (PeriodicCallback, SYSTEM_TIMER_VECTOR);\r
}\r
\r
/**\r
  DebugSupport protocol member function.\r
\r
  This code executes in boot services context.\r
\r
  @param  This              The DebugSupport instance\r
  @param  ProcessorIndex    Which processor the callback applies to.\r
  @param  NewCallback       Callback function\r
  @param  ExceptionType     Which exception to hook\r
\r
  @retval EFI_SUCCESS        Indicates the callback was registered.\r
  @retval others             Callback was not registered.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
RegisterExceptionCallback (\r
  IN EFI_DEBUG_SUPPORT_PROTOCOL *This,\r
  IN UINTN                      ProcessorIndex,\r
  IN EFI_EXCEPTION_CALLBACK     NewCallback,\r
  IN EFI_EXCEPTION_TYPE         ExceptionType\r
  )\r
{\r
  return ManageIdtEntryTable (NewCallback, ExceptionType);\r
}\r
\r
/**\r
  DebugSupport protocol member function.  Calls assembly routine to flush cache.\r
\r
  @param  This              The DebugSupport instance\r
  @param  ProcessorIndex    Which processor the callback applies to.\r
  @param  Start             Physical base of the memory range to be invalidated\r
  @param  Length            mininum number of bytes in instruction cache to invalidate\r
\r
  @retval EFI_SUCCESS       Always returned.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
InvalidateInstructionCache (\r
  IN EFI_DEBUG_SUPPORT_PROTOCOL       *This,\r
  IN UINTN                            ProcessorIndex,\r
  IN VOID                             *Start,\r
  IN UINT64                           Length\r
  )\r
{\r
  AsmWbinvd ();\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  Initializes driver's handler registration databas. \r
  \r
  This code executes in boot services context\r
  Must be public because it's referenced from DebugSupport.c\r
\r
  @retval  EFI_UNSUPPORTED      If x64 processor does not support FXSTOR/FXRSTOR instructions,\r
                                the context save will fail, so these processor's are not supported.\r
  @retval  EFI_OUT_OF_RESOURCES Fails to allocate memory.\r
  @retval  EFI_SUCCESS          Initializes successfully.\r
\r
**/\r
EFI_STATUS\r
PlInitializeDebugSupportDriver (\r
  VOID\r
  )\r
{\r
  EFI_EXCEPTION_TYPE  ExceptionType;\r
\r
  if (!FxStorSupport ()) {\r
    return EFI_UNSUPPORTED;\r
  }\r
\r
  IdtEntryTable = AllocateZeroPool (sizeof (IDT_ENTRY) * NUM_IDT_ENTRIES);\r
  if (IdtEntryTable == NULL) {\r
    return EFI_OUT_OF_RESOURCES;\r
  }\r
\r
  for (ExceptionType = 0; ExceptionType < NUM_IDT_ENTRIES; ExceptionType++) {\r
    IdtEntryTable[ExceptionType].StubEntry = (DEBUG_PROC) (UINTN) AllocatePool (StubSize);\r
    if (IdtEntryTable[ExceptionType].StubEntry == NULL) {\r
      goto ErrorCleanup;\r
    }\r
\r
    CopyMem ((VOID *)(UINTN)IdtEntryTable[ExceptionType].StubEntry, InterruptEntryStub, StubSize);\r
  }\r
  return EFI_SUCCESS;\r
\r
ErrorCleanup:\r
\r
  for (ExceptionType = 0; ExceptionType < NUM_IDT_ENTRIES; ExceptionType++) {\r
    if (IdtEntryTable[ExceptionType].StubEntry != NULL) {\r
      FreePool ((VOID *)(UINTN)IdtEntryTable[ExceptionType].StubEntry);\r
    }\r
  }\r
  FreePool (IdtEntryTable);\r
\r
  return EFI_OUT_OF_RESOURCES;\r
}\r
\r
/**\r
  This is the callback that is written to the LoadedImage protocol instance\r
  on the image handle. It uninstalls all registered handlers and frees all entry\r
  stub memory.\r
\r
  @param  ImageHandle    The firmware allocated handle for the EFI image.\r
\r
  @retval EFI_SUCCESS    Always.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
PlUnloadDebugSupportDriver (\r
  IN EFI_HANDLE ImageHandle\r
  )\r
{\r
  EFI_EXCEPTION_TYPE  ExceptionType;\r
\r
  for (ExceptionType = 0; ExceptionType < NUM_IDT_ENTRIES; ExceptionType++) {\r
    ManageIdtEntryTable (NULL, ExceptionType);\r
  }\r
\r
  FreePool (IdtEntryTable);\r
  return EFI_SUCCESS;\r
}\r
\r
/**\r
  Common piece of code that invokes the registered handlers.\r
\r
  This code executes in exception context so no efi calls are allowed.\r
\r
  @param  ExceptionType     Exception type\r
  @param  ContextRecord     System context\r
\r
**/\r
VOID\r
InterruptDistrubutionHub (\r
  EFI_EXCEPTION_TYPE      ExceptionType,\r
  EFI_SYSTEM_CONTEXT_IA32 *ContextRecord\r
  )\r
{\r
  if (IdtEntryTable[ExceptionType].RegisteredCallback != NULL) {\r
    if (ExceptionType != SYSTEM_TIMER_VECTOR) {\r
      IdtEntryTable[ExceptionType].RegisteredCallback (ExceptionType, ContextRecord);\r
    } else {\r
      OrigVector = IdtEntryTable[ExceptionType].OrigVector;\r
      IdtEntryTable[ExceptionType].RegisteredCallback (ContextRecord);\r
    }\r
  }\r
}\r
Commit	Line	Data
	1	/** @file\r
	2	X64 specific debug support functions\r
	3	\r
	4	Copyright (c) 2006 - 2007, Intel Corporation\r
	5	All rights reserved. This program and the accompanying materials\r
	6	are licensed and made available under the terms and conditions of the BSD License\r
	7	which accompanies this distribution. The full text of the license may be found at\r
	8	http://opensource.org/licenses/bsd-license.php\r
	9	\r
	10	THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
	11	WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
	12	\r
	13	**/\r
	14	\r
	15	//\r
	16	// private header files\r
	17	//\r
	18	#include "PlDebugSupport.h"\r
	19	\r
	20	//\r
	21	// This the global main table to keep track of the interrupts\r
	22	//\r
	23	IDT_ENTRY *IdtEntryTable = NULL;\r
	24	DESCRIPTOR NullDesc = {0, 0};\r
	25	\r
	26	/**\r
	27	Allocate pool for a new IDT entry stub.\r
	28	\r
	29	Copy the generic stub into the new buffer and fixup the vector number\r
	30	and jump target address.\r
	31	\r
	32	@param ExceptionType This is the exception type that the new stub will be created\r
	33	for.\r
	34	@param Stub On successful exit, *Stub contains the newly allocated entry stub.\r
	35	\r
	36	@retval EFI_SUCCESS Always.\r
	37	\r
	38	**/\r
	39	EFI_STATUS\r
	40	CreateEntryStub (\r
	41	IN EFI_EXCEPTION_TYPE ExceptionType,\r
	42	OUT VOID **Stub\r
	43	)\r
	44	{\r
	45	UINT8 *StubCopy;\r
	46	\r
	47	StubCopy = *Stub;\r
	48	\r
	49	//\r
	50	// Fixup the stub code for this vector\r
	51	//\r
	52	\r
	53	// The stub code looks like this:\r
	54	//\r
	55	// 00000000 6A 00 push 0 ; push vector number - will be modified before installed\r
	56	// 00000002 E9 db 0e9h ; jump rel32\r
	57	// 00000003 00000000 dd 0 ; fixed up to relative address of CommonIdtEntry\r
	58	//\r
	59	\r
	60	//\r
	61	// poke in the exception type so the second push pushes the exception type\r
	62	//\r
	63	StubCopy[0x1] = (UINT8) ExceptionType;\r
	64	\r
	65	//\r
	66	// fixup the jump target to point to the common entry\r
	67	//\r
	68	(UINT32 ) &StubCopy[0x3] = (UINT32)((UINTN) CommonIdtEntry - (UINTN) &StubCopy[StubSize]);\r
	69	\r
	70	return EFI_SUCCESS;\r
	71	}\r
	72	\r
	73	/**\r
	74	Creates a nes entry stub. Then saves the current IDT entry and replaces it\r
	75	with an interrupt gate for the new entry point. The IdtEntryTable is updated\r
	76	with the new registered function.\r
	77	\r
	78	This code executes in boot services context. The stub entry executes in interrupt\r
	79	context.\r
	80	\r
	81	@param ExceptionType Specifies which vector to hook.\r
	82	@param NewCallback A pointer to the new function to be registered.\r
	83	\r
	84	@retval EFI_SUCCESS Always.\r
	85	\r
	86	**/\r
	87	EFI_STATUS\r
	88	HookEntry (\r
	89	IN EFI_EXCEPTION_TYPE ExceptionType,\r
	90	IN VOID (*NewCallback) ()\r
	91	)\r
	92	{\r
	93	BOOLEAN OldIntFlagState;\r
	94	EFI_STATUS Status;\r
	95	\r
	96	Status = CreateEntryStub (ExceptionType, (VOID **) &IdtEntryTable[ExceptionType].StubEntry);\r
	97	if (Status == EFI_SUCCESS) {\r
	98	OldIntFlagState = WriteInterruptFlag (0);\r
	99	READ_IDT (ExceptionType, &(IdtEntryTable[ExceptionType].OrigDesc));\r
	100	\r
	101	((UINT16 ) &IdtEntryTable[ExceptionType].OrigVector)[0] = ((UINT16 ) &IdtEntryTable[ExceptionType].OrigDesc.Low)[0];\r
	102	((UINT16 ) &IdtEntryTable[ExceptionType].OrigVector)[1] = ((UINT16 ) &IdtEntryTable[ExceptionType].OrigDesc.Low)[3];\r
	103	((UINT32 ) &IdtEntryTable[ExceptionType].OrigVector)[1] = ((UINT32 ) &IdtEntryTable[ExceptionType].OrigDesc.High)[0];\r
	104	\r
	105	Vect2Desc (&IdtEntryTable[ExceptionType].NewDesc, IdtEntryTable[ExceptionType].StubEntry);\r
	106	IdtEntryTable[ExceptionType].RegisteredCallback = NewCallback;\r
	107	WRITE_IDT (ExceptionType, &(IdtEntryTable[ExceptionType].NewDesc));\r
	108	WriteInterruptFlag (OldIntFlagState);\r
	109	}\r
	110	\r
	111	return Status;\r
	112	}\r
	113	\r
	114	/**\r
	115	Undoes HookEntry. This code executes in boot services context.\r
	116	\r
	117	@param ExceptionType Specifies which entry to unhook\r
	118	\r
	119	@retval EFI_SUCCESS Always.\r
	120	\r
	121	**/\r
	122	EFI_STATUS\r
	123	UnhookEntry (\r
	124	IN EFI_EXCEPTION_TYPE ExceptionType\r
	125	)\r
	126	{\r
	127	BOOLEAN OldIntFlagState;\r
	128	\r
	129	OldIntFlagState = WriteInterruptFlag (0);\r
	130	WRITE_IDT (ExceptionType, &(IdtEntryTable[ExceptionType].OrigDesc));\r
	131	WriteInterruptFlag (OldIntFlagState);\r
	132	\r
	133	return EFI_SUCCESS;\r
	134	}\r
	135	\r
	136	/**\r
	137	This is the main worker function that manages the state of the interrupt\r
	138	handlers. It both installs and uninstalls interrupt handlers based on the\r
	139	value of NewCallback. If NewCallback is NULL, then uninstall is indicated.\r
	140	If NewCallback is non-NULL, then install is indicated.\r
	141	\r
	142	@param NewCallback If non-NULL, NewCallback specifies the new handler to register.\r
	143	If NULL, specifies that the previously registered handler should\r
	144	be uninstalled.\r
	145	@param ExceptionType Indicates which entry to manage.\r
	146	\r
	147	@retval EFI_SUCCESS Process is ok.\r
	148	@retval EFI_INVALID_PARAMETER Requested uninstalling a handler from a vector that has\r
	149	no handler registered for it\r
	150	@retval EFI_ALREADY_STARTED Requested install to a vector that already has a handler registered.\r
	151	@retval others Possible return values are passed through from UnHookEntry and HookEntry.\r
	152	\r
	153	**/\r
	154	EFI_STATUS\r
	155	ManageIdtEntryTable (\r
	156	VOID (*NewCallback)(),\r
	157	EFI_EXCEPTION_TYPE ExceptionType\r
	158	)\r
	159	{\r
	160	EFI_STATUS Status;\r
	161	\r
	162	Status = EFI_SUCCESS;\r
	163	\r
	164	if (COMPARE_DESCRIPTOR (&IdtEntryTable[ExceptionType].NewDesc, &NullDesc)) {\r
	165	//\r
	166	// we've already installed to this vector\r
	167	//\r
	168	if (NewCallback != NULL) {\r
	169	//\r
	170	// if the input handler is non-null, error\r
	171	//\r
	172	Status = EFI_ALREADY_STARTED;\r
	173	} else {\r
	174	Status = UnhookEntry (ExceptionType);\r
	175	}\r
	176	} else {\r
	177	//\r
	178	// no user handler installed on this vector\r
	179	//\r
	180	if (NewCallback == NULL) {\r
	181	//\r
	182	// if the input handler is null, error\r
	183	//\r
	184	Status = EFI_INVALID_PARAMETER;\r
	185	} else {\r
	186	Status = HookEntry (ExceptionType, NewCallback);\r
	187	}\r
	188	}\r
	189	\r
	190	return Status;\r
	191	}\r
	192	\r
	193	/**\r
	194	This is a DebugSupport protocol member function, hard\r
	195	coded to support only 1 processor for now.\r
	196	\r
	197	@param This The DebugSupport instance\r
	198	@param MaxProcessorIndex The maximuim supported processor index\r
	199	\r
	200	@retval EFI_SUCCESS Always returned with **MaxProcessorIndex set to 0.\r
	201	\r
	202	**/\r
	203	EFI_STATUS\r
	204	EFIAPI\r
	205	GetMaximumProcessorIndex (\r
	206	IN EFI_DEBUG_SUPPORT_PROTOCOL *This,\r
	207	OUT UINTN *MaxProcessorIndex\r
	208	)\r
	209	{\r
	210	*MaxProcessorIndex = 0;\r
	211	return (EFI_SUCCESS);\r
	212	}\r
	213	\r
	214	/**\r
	215	DebugSupport protocol member function.\r
	216	\r
	217	@param This The DebugSupport instance\r
	218	@param ProcessorIndex Which processor the callback applies to.\r
	219	@param PeriodicCallback Callback function\r
	220	\r
	221	@retval EFI_SUCCESS Indicates the callback was registered.\r
	222	@retval others Callback was not registered.\r
	223	\r
	224	**/\r
	225	EFI_STATUS\r
	226	EFIAPI\r
	227	RegisterPeriodicCallback (\r
	228	IN EFI_DEBUG_SUPPORT_PROTOCOL *This,\r
	229	IN UINTN ProcessorIndex,\r
	230	IN EFI_PERIODIC_CALLBACK PeriodicCallback\r
	231	)\r
	232	{\r
	233	return ManageIdtEntryTable (PeriodicCallback, SYSTEM_TIMER_VECTOR);\r
	234	}\r
	235	\r
	236	/**\r
	237	DebugSupport protocol member function.\r
	238	\r
	239	This code executes in boot services context.\r
	240	\r
	241	@param This The DebugSupport instance\r
	242	@param ProcessorIndex Which processor the callback applies to.\r
	243	@param NewCallback Callback function\r
	244	@param ExceptionType Which exception to hook\r
	245	\r
	246	@retval EFI_SUCCESS Indicates the callback was registered.\r
	247	@retval others Callback was not registered.\r
	248	\r
	249	**/\r
	250	EFI_STATUS\r
	251	EFIAPI\r
	252	RegisterExceptionCallback (\r
	253	IN EFI_DEBUG_SUPPORT_PROTOCOL *This,\r
	254	IN UINTN ProcessorIndex,\r
	255	IN EFI_EXCEPTION_CALLBACK NewCallback,\r
	256	IN EFI_EXCEPTION_TYPE ExceptionType\r
	257	)\r
	258	{\r
	259	return ManageIdtEntryTable (NewCallback, ExceptionType);\r
	260	}\r
	261	\r
	262	/**\r
	263	DebugSupport protocol member function. Calls assembly routine to flush cache.\r
	264	\r
	265	@param This The DebugSupport instance\r
	266	@param ProcessorIndex Which processor the callback applies to.\r
	267	@param Start Physical base of the memory range to be invalidated\r
	268	@param Length mininum number of bytes in instruction cache to invalidate\r
	269	\r
	270	@retval EFI_SUCCESS Always returned.\r
	271	\r
	272	**/\r
	273	EFI_STATUS\r
	274	EFIAPI\r
	275	InvalidateInstructionCache (\r
	276	IN EFI_DEBUG_SUPPORT_PROTOCOL *This,\r
	277	IN UINTN ProcessorIndex,\r
	278	IN VOID *Start,\r
	279	IN UINT64 Length\r
	280	)\r
	281	{\r
	282	AsmWbinvd ();\r
	283	return EFI_SUCCESS;\r
	284	}\r
	285	\r
	286	/**\r
	287	Initializes driver's handler registration databas. \r
	288	\r
	289	This code executes in boot services context\r
	290	Must be public because it's referenced from DebugSupport.c\r
	291	\r
	292	@retval EFI_UNSUPPORTED If x64 processor does not support FXSTOR/FXRSTOR instructions,\r
	293	the context save will fail, so these processor's are not supported.\r
	294	@retval EFI_OUT_OF_RESOURCES Fails to allocate memory.\r
	295	@retval EFI_SUCCESS Initializes successfully.\r
	296	\r
	297	**/\r
	298	EFI_STATUS\r
	299	PlInitializeDebugSupportDriver (\r
	300	VOID\r
	301	)\r
	302	{\r
	303	EFI_EXCEPTION_TYPE ExceptionType;\r
	304	\r
	305	if (!FxStorSupport ()) {\r
	306	return EFI_UNSUPPORTED;\r
	307	}\r
	308	\r
	309	IdtEntryTable = AllocateZeroPool (sizeof (IDT_ENTRY) * NUM_IDT_ENTRIES);\r
	310	if (IdtEntryTable == NULL) {\r
	311	return EFI_OUT_OF_RESOURCES;\r
	312	}\r
	313	\r
	314	for (ExceptionType = 0; ExceptionType < NUM_IDT_ENTRIES; ExceptionType++) {\r
	315	IdtEntryTable[ExceptionType].StubEntry = (DEBUG_PROC) (UINTN) AllocatePool (StubSize);\r
	316	if (IdtEntryTable[ExceptionType].StubEntry == NULL) {\r
	317	goto ErrorCleanup;\r
	318	}\r
	319	\r
	320	CopyMem ((VOID *)(UINTN)IdtEntryTable[ExceptionType].StubEntry, InterruptEntryStub, StubSize);\r
	321	}\r
	322	return EFI_SUCCESS;\r
	323	\r
	324	ErrorCleanup:\r
	325	\r
	326	for (ExceptionType = 0; ExceptionType < NUM_IDT_ENTRIES; ExceptionType++) {\r
	327	if (IdtEntryTable[ExceptionType].StubEntry != NULL) {\r
	328	FreePool ((VOID *)(UINTN)IdtEntryTable[ExceptionType].StubEntry);\r
	329	}\r
	330	}\r
	331	FreePool (IdtEntryTable);\r
	332	\r
	333	return EFI_OUT_OF_RESOURCES;\r
	334	}\r
	335	\r
	336	/**\r
	337	This is the callback that is written to the LoadedImage protocol instance\r
	338	on the image handle. It uninstalls all registered handlers and frees all entry\r
	339	stub memory.\r
	340	\r
	341	@param ImageHandle The firmware allocated handle for the EFI image.\r
	342	\r
	343	@retval EFI_SUCCESS Always.\r
	344	\r
	345	**/\r
	346	EFI_STATUS\r
	347	EFIAPI\r
	348	PlUnloadDebugSupportDriver (\r
	349	IN EFI_HANDLE ImageHandle\r
	350	)\r
	351	{\r
	352	EFI_EXCEPTION_TYPE ExceptionType;\r
	353	\r
	354	for (ExceptionType = 0; ExceptionType < NUM_IDT_ENTRIES; ExceptionType++) {\r
	355	ManageIdtEntryTable (NULL, ExceptionType);\r
	356	}\r
	357	\r
	358	FreePool (IdtEntryTable);\r
	359	return EFI_SUCCESS;\r
	360	}\r
	361	\r
	362	/**\r
	363	Common piece of code that invokes the registered handlers.\r
	364	\r
	365	This code executes in exception context so no efi calls are allowed.\r
	366	\r
	367	@param ExceptionType Exception type\r
	368	@param ContextRecord System context\r
	369	\r
	370	**/\r
	371	VOID\r
	372	InterruptDistrubutionHub (\r
	373	EFI_EXCEPTION_TYPE ExceptionType,\r
	374	EFI_SYSTEM_CONTEXT_IA32 *ContextRecord\r
	375	)\r
	376	{\r
	377	if (IdtEntryTable[ExceptionType].RegisteredCallback != NULL) {\r
	378	if (ExceptionType != SYSTEM_TIMER_VECTOR) {\r
	379	IdtEntryTable[ExceptionType].RegisteredCallback (ExceptionType, ContextRecord);\r
	380	} else {\r
	381	OrigVector = IdtEntryTable[ExceptionType].OrigVector;\r
	382	IdtEntryTable[ExceptionType].RegisteredCallback (ContextRecord);\r
	383	}\r
	384	}\r
	385	}\r