[mirror_edk2.git] / EmulatorPkg / TimerDxe / Timer.c

/*++ @file\r
  Emu Emulation Timer Architectural Protocol Driver as defined in DXE CIS\r
\r
  This Timer module uses an Emu Thread to simulate the timer-tick driven\r
  timer service.  In the future, the Thread creation should possibly be\r
  abstracted by the CPU architectural protocol\r
\r
Copyright (c) 2004 - 2016, Intel Corporation. All rights reserved.<BR>\r
Portions copyright (c) 2010 - 2011, Apple Inc. All rights reserved.\r
SPDX-License-Identifier: BSD-2-Clause-Patent\r
\r
\r
**/\r
\r
#include "PiDxe.h"\r
#include <Protocol/Timer.h>\r
#include <Protocol/Cpu.h>\r
#include "Timer.h"\r
#include <Library/BaseLib.h>\r
#include <Library/DebugLib.h>\r
#include <Library/UefiLib.h>\r
#include <Library/UefiDriverEntryPoint.h>\r
#include <Library/MemoryAllocationLib.h>\r
#include <Library/UefiBootServicesTableLib.h>\r
#include <Library/EmuThunkLib.h>\r
\r
//\r
// Pointer to the CPU Architectural Protocol instance\r
//\r
EFI_CPU_ARCH_PROTOCOL  *mCpu;\r
\r
//\r
// The Timer Architectural Protocol that this driver produces\r
//\r
EFI_TIMER_ARCH_PROTOCOL  mTimer = {\r
  EmuTimerDriverRegisterHandler,\r
  EmuTimerDriverSetTimerPeriod,\r
  EmuTimerDriverGetTimerPeriod,\r
  EmuTimerDriverGenerateSoftInterrupt\r
};\r
\r
//\r
// The notification function to call on every timer interrupt\r
//\r
EFI_TIMER_NOTIFY  mTimerNotifyFunction = NULL;\r
\r
//\r
// The current period of the timer interrupt\r
//\r
UINT64  mTimerPeriodMs;\r
\r
VOID\r
EFIAPI\r
TimerCallback (\r
  UINT64  DeltaMs\r
  )\r
{\r
  EFI_TPL           OriginalTPL;\r
  EFI_TIMER_NOTIFY  CallbackFunction;\r
\r
  OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);\r
\r
  if (OriginalTPL < TPL_HIGH_LEVEL) {\r
    CallbackFunction = mTimerNotifyFunction;\r
\r
    //\r
    // Only invoke the callback function if a Non-NULL handler has been\r
    // registered. Assume all other handlers are legal.\r
    //\r
    if (CallbackFunction != NULL) {\r
      CallbackFunction (MultU64x32 (DeltaMs, 10000));\r
    }\r
  }\r
\r
  gBS->RestoreTPL (OriginalTPL);\r
}\r
\r
EFI_STATUS\r
EFIAPI\r
EmuTimerDriverRegisterHandler (\r
  IN EFI_TIMER_ARCH_PROTOCOL  *This,\r
  IN EFI_TIMER_NOTIFY         NotifyFunction\r
  )\r
\r
/*++\r
\r
Routine Description:\r
\r
  This function registers the handler NotifyFunction so it is called every time\r
  the timer interrupt fires.  It also passes the amount of time since the last\r
  handler call to the NotifyFunction.  If NotifyFunction is NULL, then the\r
  handler is unregistered.  If the handler is registered, then EFI_SUCCESS is\r
  returned.  If the CPU does not support registering a timer interrupt handler,\r
  then EFI_UNSUPPORTED is returned.  If an attempt is made to register a handler\r
  when a handler is already registered, then EFI_ALREADY_STARTED is returned.\r
  If an attempt is made to unregister a handler when a handler is not registered,\r
  then EFI_INVALID_PARAMETER is returned.  If an error occurs attempting to\r
  register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR\r
  is returned.\r
\r
Arguments:\r
\r
  This           - The EFI_TIMER_ARCH_PROTOCOL instance.\r
\r
  NotifyFunction - The function to call when a timer interrupt fires.  This\r
                   function executes at TPL_HIGH_LEVEL.  The DXE Core will\r
                   register a handler for the timer interrupt, so it can know\r
                   how much time has passed.  This information is used to\r
                   signal timer based events.  NULL will unregister the handler.\r
\r
Returns:\r
\r
  EFI_SUCCESS           - The timer handler was registered.\r
\r
  EFI_UNSUPPORTED       - The platform does not support timer interrupts.\r
\r
  EFI_ALREADY_STARTED   - NotifyFunction is not NULL, and a handler is already\r
                          registered.\r
\r
  EFI_INVALID_PARAMETER - NotifyFunction is NULL, and a handler was not\r
                          previously registered.\r
\r
  EFI_DEVICE_ERROR      - The timer handler could not be registered.\r
\r
**/\r
{\r
  //\r
  // Check for invalid parameters\r
  //\r
  if ((NotifyFunction == NULL) && (mTimerNotifyFunction == NULL)) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  if ((NotifyFunction != NULL) && (mTimerNotifyFunction != NULL)) {\r
    return EFI_ALREADY_STARTED;\r
  }\r
\r
  if (NotifyFunction == NULL) {\r
    /* Disable timer.  */\r
    gEmuThunk->SetTimer (0, TimerCallback);\r
  } else if (mTimerNotifyFunction == NULL) {\r
    /* Enable Timer.  */\r
    gEmuThunk->SetTimer (mTimerPeriodMs, TimerCallback);\r
  }\r
\r
  mTimerNotifyFunction = NotifyFunction;\r
\r
  return EFI_SUCCESS;\r
}\r
\r
EFI_STATUS\r
EFIAPI\r
EmuTimerDriverSetTimerPeriod (\r
  IN EFI_TIMER_ARCH_PROTOCOL  *This,\r
  IN UINT64                   TimerPeriod\r
  )\r
\r
/*++\r
\r
Routine Description:\r
\r
  This function adjusts the period of timer interrupts to the value specified\r
  by TimerPeriod.  If the timer period is updated, then the selected timer\r
  period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned.  If\r
  the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.\r
  If an error occurs while attempting to update the timer period, then the\r
  timer hardware will be put back in its state prior to this call, and\r
  EFI_DEVICE_ERROR is returned.  If TimerPeriod is 0, then the timer interrupt\r
  is disabled.  This is not the same as disabling the CPU's interrupts.\r
  Instead, it must either turn off the timer hardware, or it must adjust the\r
  interrupt controller so that a CPU interrupt is not generated when the timer\r
  interrupt fires.\r
\r
Arguments:\r
\r
  This        - The EFI_TIMER_ARCH_PROTOCOL instance.\r
\r
  TimerPeriod - The rate to program the timer interrupt in 100 nS units.  If\r
                the timer hardware is not programmable, then EFI_UNSUPPORTED is\r
                returned.  If the timer is programmable, then the timer period\r
                will be rounded up to the nearest timer period that is supported\r
                by the timer hardware.  If TimerPeriod is set to 0, then the\r
                timer interrupts will be disabled.\r
\r
Returns:\r
\r
  EFI_SUCCESS      - The timer period was changed.\r
\r
  EFI_UNSUPPORTED  - The platform cannot change the period of the timer interrupt.\r
\r
  EFI_DEVICE_ERROR - The timer period could not be changed due to a device error.\r
\r
**/\r
{\r
  //\r
  // If TimerPeriod is 0, then the timer thread should be canceled\r
  // If the TimerPeriod is valid, then create and/or adjust the period of the timer thread\r
  //\r
  if (  (TimerPeriod == 0)\r
     || (  (TimerPeriod > TIMER_MINIMUM_VALUE)\r
        && (TimerPeriod < TIMER_MAXIMUM_VALUE)))\r
  {\r
    mTimerPeriodMs = DivU64x32 (TimerPeriod + 5000, 10000);\r
\r
    gEmuThunk->SetTimer (mTimerPeriodMs, TimerCallback);\r
  }\r
\r
  return EFI_SUCCESS;\r
}\r
\r
EFI_STATUS\r
EFIAPI\r
EmuTimerDriverGetTimerPeriod (\r
  IN EFI_TIMER_ARCH_PROTOCOL  *This,\r
  OUT UINT64                  *TimerPeriod\r
  )\r
\r
/*++\r
\r
Routine Description:\r
\r
  This function retrieves the period of timer interrupts in 100 ns units,\r
  returns that value in TimerPeriod, and returns EFI_SUCCESS.  If TimerPeriod\r
  is NULL, then EFI_INVALID_PARAMETER is returned.  If a TimerPeriod of 0 is\r
  returned, then the timer is currently disabled.\r
\r
Arguments:\r
\r
  This        - The EFI_TIMER_ARCH_PROTOCOL instance.\r
\r
  TimerPeriod - A pointer to the timer period to retrieve in 100 ns units.  If\r
                0 is returned, then the timer is currently disabled.\r
\r
Returns:\r
\r
  EFI_SUCCESS           - The timer period was returned in TimerPeriod.\r
\r
  EFI_INVALID_PARAMETER - TimerPeriod is NULL.\r
\r
**/\r
{\r
  if (TimerPeriod == NULL) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  *TimerPeriod = MultU64x32 (mTimerPeriodMs, 10000);\r
\r
  return EFI_SUCCESS;\r
}\r
\r
EFI_STATUS\r
EFIAPI\r
EmuTimerDriverGenerateSoftInterrupt (\r
  IN EFI_TIMER_ARCH_PROTOCOL  *This\r
  )\r
\r
/*++\r
\r
Routine Description:\r
\r
  This function generates a soft timer interrupt. If the platform does not support soft\r
  timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned.\r
  If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler()\r
  service, then a soft timer interrupt will be generated. If the timer interrupt is\r
  enabled when this service is called, then the registered handler will be invoked. The\r
  registered handler should not be able to distinguish a hardware-generated timer\r
  interrupt from a software-generated timer interrupt.\r
\r
Arguments:\r
\r
  This  -  The EFI_TIMER_ARCH_PROTOCOL instance.\r
\r
Returns:\r
\r
  EFI_SUCCESS       - The soft timer interrupt was generated.\r
\r
  EFI_UNSUPPORTED   - The platform does not support the generation of soft timer interrupts.\r
\r
**/\r
{\r
  return EFI_UNSUPPORTED;\r
}\r
\r
EFI_STATUS\r
EFIAPI\r
EmuTimerDriverInitialize (\r
  IN EFI_HANDLE        ImageHandle,\r
  IN EFI_SYSTEM_TABLE  *SystemTable\r
  )\r
\r
/*++\r
\r
Routine Description:\r
\r
  Initialize the Timer Architectural Protocol driver\r
\r
Arguments:\r
\r
  ImageHandle - ImageHandle of the loaded driver\r
\r
  SystemTable - Pointer to the System Table\r
\r
Returns:\r
\r
  EFI_SUCCESS           - Timer Architectural Protocol created\r
\r
  EFI_OUT_OF_RESOURCES  - Not enough resources available to initialize driver.\r
\r
  EFI_DEVICE_ERROR      - A device error occurred attempting to initialize the driver.\r
\r
**/\r
{\r
  EFI_STATUS  Status;\r
  EFI_HANDLE  Handle;\r
\r
  //\r
  // Make sure the Timer Architectural Protocol is not already installed in the system\r
  //\r
  ASSERT_PROTOCOL_ALREADY_INSTALLED (NULL, &gEfiTimerArchProtocolGuid);\r
\r
  //\r
  // Get the CPU Architectural Protocol instance\r
  //\r
  Status = gBS->LocateProtocol (&gEfiCpuArchProtocolGuid, NULL, (void *)&mCpu);\r
  ASSERT_EFI_ERROR (Status);\r
\r
  //\r
  // Start the timer thread at the default timer period\r
  //\r
  Status = mTimer.SetTimerPeriod (&mTimer, DEFAULT_TIMER_TICK_DURATION);\r
  if (EFI_ERROR (Status)) {\r
    return Status;\r
  }\r
\r
  //\r
  // Install the Timer Architectural Protocol onto a new handle\r
  //\r
  Handle = NULL;\r
  Status = gBS->InstallProtocolInterface (\r
                  &Handle,\r
                  &gEfiTimerArchProtocolGuid,\r
                  EFI_NATIVE_INTERFACE,\r
                  &mTimer\r
                  );\r
  if (EFI_ERROR (Status)) {\r
    return Status;\r
  }\r
\r
  return EFI_SUCCESS;\r
}\r
Commit	Line	Data
949f388f	1	/*++ @file\r
	2	Emu Emulation Timer Architectural Protocol Driver as defined in DXE CIS\r
	3	\r
	4	This Timer module uses an Emu Thread to simulate the timer-tick driven\r
	5	timer service. In the future, the Thread creation should possibly be\r
	6	abstracted by the CPU architectural protocol\r
	7	\r
daea123d	8	Copyright (c) 2004 - 2016, Intel Corporation. All rights reserved.<BR>\r
949f388f	9	Portions copyright (c) 2010 - 2011, Apple Inc. All rights reserved.\r
e3ba31da	10	SPDX-License-Identifier: BSD-2-Clause-Patent\r
949f388f	11	\r
	12	\r
	13	**/\r
	14	\r
	15	#include "PiDxe.h"\r
	16	#include <Protocol/Timer.h>\r
	17	#include <Protocol/Cpu.h>\r
	18	#include "Timer.h"\r
	19	#include <Library/BaseLib.h>\r
	20	#include <Library/DebugLib.h>\r
	21	#include <Library/UefiLib.h>\r
	22	#include <Library/UefiDriverEntryPoint.h>\r
	23	#include <Library/MemoryAllocationLib.h>\r
	24	#include <Library/UefiBootServicesTableLib.h>\r
	25	#include <Library/EmuThunkLib.h>\r
	26	\r
	27	//\r
	28	// Pointer to the CPU Architectural Protocol instance\r
	29	//\r
a550d468	30	EFI_CPU_ARCH_PROTOCOL *mCpu;\r
949f388f	31	\r
	32	//\r
	33	// The Timer Architectural Protocol that this driver produces\r
	34	//\r
a550d468	35	EFI_TIMER_ARCH_PROTOCOL mTimer = {\r
949f388f	36	EmuTimerDriverRegisterHandler,\r
	37	EmuTimerDriverSetTimerPeriod,\r
	38	EmuTimerDriverGetTimerPeriod,\r
	39	EmuTimerDriverGenerateSoftInterrupt\r
	40	};\r
	41	\r
	42	//\r
	43	// The notification function to call on every timer interrupt\r
	44	//\r
a550d468	45	EFI_TIMER_NOTIFY mTimerNotifyFunction = NULL;\r
949f388f	46	\r
	47	//\r
	48	// The current period of the timer interrupt\r
	49	//\r
a550d468	50	UINT64 mTimerPeriodMs;\r
949f388f	51	\r
	52	VOID\r
	53	EFIAPI\r
a550d468 MK	54	TimerCallback (\r
	55	UINT64 DeltaMs\r
	56	)\r
949f388f	57	{\r
	58	EFI_TPL OriginalTPL;\r
	59	EFI_TIMER_NOTIFY CallbackFunction;\r
	60	\r
949f388f	61	OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);\r
	62	\r
	63	if (OriginalTPL < TPL_HIGH_LEVEL) {\r
	64	CallbackFunction = mTimerNotifyFunction;\r
	65	\r
	66	//\r
	67	// Only invoke the callback function if a Non-NULL handler has been\r
	68	// registered. Assume all other handlers are legal.\r
	69	//\r
	70	if (CallbackFunction != NULL) {\r
e148512e	71	CallbackFunction (MultU64x32 (DeltaMs, 10000));\r
949f388f	72	}\r
	73	}\r
	74	\r
	75	gBS->RestoreTPL (OriginalTPL);\r
949f388f	76	}\r
	77	\r
	78	EFI_STATUS\r
	79	EFIAPI\r
	80	EmuTimerDriverRegisterHandler (\r
a550d468 MK	81	IN EFI_TIMER_ARCH_PROTOCOL *This,\r
a550d468 MK	82	IN EFI_TIMER_NOTIFY NotifyFunction\r
949f388f	83	)\r
a550d468	84	\r
949f388f	85	/*++\r
	86	\r
	87	Routine Description:\r
	88	\r
	89	This function registers the handler NotifyFunction so it is called every time\r
	90	the timer interrupt fires. It also passes the amount of time since the last\r
	91	handler call to the NotifyFunction. If NotifyFunction is NULL, then the\r
	92	handler is unregistered. If the handler is registered, then EFI_SUCCESS is\r
	93	returned. If the CPU does not support registering a timer interrupt handler,\r
	94	then EFI_UNSUPPORTED is returned. If an attempt is made to register a handler\r
	95	when a handler is already registered, then EFI_ALREADY_STARTED is returned.\r
	96	If an attempt is made to unregister a handler when a handler is not registered,\r
	97	then EFI_INVALID_PARAMETER is returned. If an error occurs attempting to\r
	98	register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR\r
	99	is returned.\r
	100	\r
	101	Arguments:\r
	102	\r
	103	This - The EFI_TIMER_ARCH_PROTOCOL instance.\r
	104	\r
	105	NotifyFunction - The function to call when a timer interrupt fires. This\r
	106	function executes at TPL_HIGH_LEVEL. The DXE Core will\r
	107	register a handler for the timer interrupt, so it can know\r
	108	how much time has passed. This information is used to\r
	109	signal timer based events. NULL will unregister the handler.\r
	110	\r
	111	Returns:\r
	112	\r
	113	EFI_SUCCESS - The timer handler was registered.\r
	114	\r
	115	EFI_UNSUPPORTED - The platform does not support timer interrupts.\r
	116	\r
	117	EFI_ALREADY_STARTED - NotifyFunction is not NULL, and a handler is already\r
	118	registered.\r
	119	\r
	120	EFI_INVALID_PARAMETER - NotifyFunction is NULL, and a handler was not\r
	121	previously registered.\r
	122	\r
	123	EFI_DEVICE_ERROR - The timer handler could not be registered.\r
	124	\r
	125	**/\r
	126	{\r
	127	//\r
	128	// Check for invalid parameters\r
	129	//\r
a550d468	130	if ((NotifyFunction == NULL) && (mTimerNotifyFunction == NULL)) {\r
949f388f	131	return EFI_INVALID_PARAMETER;\r
	132	}\r
	133	\r
a550d468	134	if ((NotifyFunction != NULL) && (mTimerNotifyFunction != NULL)) {\r
949f388f	135	return EFI_ALREADY_STARTED;\r
	136	}\r
	137	\r
	138	if (NotifyFunction == NULL) {\r
	139	/* Disable timer. */\r
	140	gEmuThunk->SetTimer (0, TimerCallback);\r
	141	} else if (mTimerNotifyFunction == NULL) {\r
	142	/* Enable Timer. */\r
	143	gEmuThunk->SetTimer (mTimerPeriodMs, TimerCallback);\r
	144	}\r
a550d468	145	\r
949f388f	146	mTimerNotifyFunction = NotifyFunction;\r
	147	\r
	148	return EFI_SUCCESS;\r
	149	}\r
	150	\r
	151	EFI_STATUS\r
	152	EFIAPI\r
	153	EmuTimerDriverSetTimerPeriod (\r
	154	IN EFI_TIMER_ARCH_PROTOCOL *This,\r
	155	IN UINT64 TimerPeriod\r
	156	)\r
a550d468	157	\r
949f388f	158	/*++\r
	159	\r
	160	Routine Description:\r
	161	\r
	162	This function adjusts the period of timer interrupts to the value specified\r
	163	by TimerPeriod. If the timer period is updated, then the selected timer\r
	164	period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned. If\r
	165	the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.\r
	166	If an error occurs while attempting to update the timer period, then the\r
	167	timer hardware will be put back in its state prior to this call, and\r
	168	EFI_DEVICE_ERROR is returned. If TimerPeriod is 0, then the timer interrupt\r
	169	is disabled. This is not the same as disabling the CPU's interrupts.\r
	170	Instead, it must either turn off the timer hardware, or it must adjust the\r
	171	interrupt controller so that a CPU interrupt is not generated when the timer\r
	172	interrupt fires.\r
	173	\r
	174	Arguments:\r
	175	\r
	176	This - The EFI_TIMER_ARCH_PROTOCOL instance.\r
	177	\r
	178	TimerPeriod - The rate to program the timer interrupt in 100 nS units. If\r
	179	the timer hardware is not programmable, then EFI_UNSUPPORTED is\r
	180	returned. If the timer is programmable, then the timer period\r
	181	will be rounded up to the nearest timer period that is supported\r
	182	by the timer hardware. If TimerPeriod is set to 0, then the\r
	183	timer interrupts will be disabled.\r
	184	\r
	185	Returns:\r
	186	\r
	187	EFI_SUCCESS - The timer period was changed.\r
	188	\r
	189	EFI_UNSUPPORTED - The platform cannot change the period of the timer interrupt.\r
	190	\r
	191	EFI_DEVICE_ERROR - The timer period could not be changed due to a device error.\r
	192	\r
	193	**/\r
	194	{\r
949f388f	195	//\r
	196	// If TimerPeriod is 0, then the timer thread should be canceled\r
	197	// If the TimerPeriod is valid, then create and/or adjust the period of the timer thread\r
	198	//\r
a550d468 MK	199	if ( (TimerPeriod == 0)\r
	200	\|\| ( (TimerPeriod > TIMER_MINIMUM_VALUE)\r
	201	&& (TimerPeriod < TIMER_MAXIMUM_VALUE)))\r
	202	{\r
949f388f	203	mTimerPeriodMs = DivU64x32 (TimerPeriod + 5000, 10000);\r
	204	\r
	205	gEmuThunk->SetTimer (mTimerPeriodMs, TimerCallback);\r
	206	}\r
	207	\r
	208	return EFI_SUCCESS;\r
	209	}\r
	210	\r
	211	EFI_STATUS\r
	212	EFIAPI\r
	213	EmuTimerDriverGetTimerPeriod (\r
a550d468 MK	214	IN EFI_TIMER_ARCH_PROTOCOL *This,\r
a550d468 MK	215	OUT UINT64 *TimerPeriod\r
949f388f	216	)\r
a550d468	217	\r
949f388f	218	/*++\r
	219	\r
	220	Routine Description:\r
	221	\r
	222	This function retrieves the period of timer interrupts in 100 ns units,\r
	223	returns that value in TimerPeriod, and returns EFI_SUCCESS. If TimerPeriod\r
	224	is NULL, then EFI_INVALID_PARAMETER is returned. If a TimerPeriod of 0 is\r
	225	returned, then the timer is currently disabled.\r
	226	\r
	227	Arguments:\r
	228	\r
	229	This - The EFI_TIMER_ARCH_PROTOCOL instance.\r
	230	\r
	231	TimerPeriod - A pointer to the timer period to retrieve in 100 ns units. If\r
	232	0 is returned, then the timer is currently disabled.\r
	233	\r
	234	Returns:\r
	235	\r
	236	EFI_SUCCESS - The timer period was returned in TimerPeriod.\r
	237	\r
	238	EFI_INVALID_PARAMETER - TimerPeriod is NULL.\r
	239	\r
	240	**/\r
	241	{\r
	242	if (TimerPeriod == NULL) {\r
	243	return EFI_INVALID_PARAMETER;\r
	244	}\r
	245	\r
e148512e	246	*TimerPeriod = MultU64x32 (mTimerPeriodMs, 10000);\r
949f388f	247	\r
	248	return EFI_SUCCESS;\r
	249	}\r
	250	\r
	251	EFI_STATUS\r
	252	EFIAPI\r
	253	EmuTimerDriverGenerateSoftInterrupt (\r
	254	IN EFI_TIMER_ARCH_PROTOCOL *This\r
	255	)\r
a550d468	256	\r
949f388f	257	/*++\r
	258	\r
	259	Routine Description:\r
	260	\r
	261	This function generates a soft timer interrupt. If the platform does not support soft\r
	262	timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned.\r
	263	If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler()\r
	264	service, then a soft timer interrupt will be generated. If the timer interrupt is\r
	265	enabled when this service is called, then the registered handler will be invoked. The\r
	266	registered handler should not be able to distinguish a hardware-generated timer\r
	267	interrupt from a software-generated timer interrupt.\r
	268	\r
	269	Arguments:\r
	270	\r
	271	This - The EFI_TIMER_ARCH_PROTOCOL instance.\r
	272	\r
	273	Returns:\r
	274	\r
	275	EFI_SUCCESS - The soft timer interrupt was generated.\r
	276	\r
daea123d	277	EFI_UNSUPPORTED - The platform does not support the generation of soft timer interrupts.\r
949f388f	278	\r
	279	**/\r
	280	{\r
	281	return EFI_UNSUPPORTED;\r
	282	}\r
	283	\r
	284	EFI_STATUS\r
	285	EFIAPI\r
	286	EmuTimerDriverInitialize (\r
	287	IN EFI_HANDLE ImageHandle,\r
	288	IN EFI_SYSTEM_TABLE *SystemTable\r
	289	)\r
a550d468	290	\r
949f388f	291	/*++\r
	292	\r
	293	Routine Description:\r
	294	\r
	295	Initialize the Timer Architectural Protocol driver\r
	296	\r
	297	Arguments:\r
	298	\r
	299	ImageHandle - ImageHandle of the loaded driver\r
	300	\r
	301	SystemTable - Pointer to the System Table\r
	302	\r
	303	Returns:\r
	304	\r
	305	EFI_SUCCESS - Timer Architectural Protocol created\r
	306	\r
	307	EFI_OUT_OF_RESOURCES - Not enough resources available to initialize driver.\r
	308	\r
f034c05c	309	EFI_DEVICE_ERROR - A device error occurred attempting to initialize the driver.\r
949f388f	310	\r
	311	**/\r
	312	{\r
	313	EFI_STATUS Status;\r
	314	EFI_HANDLE Handle;\r
	315	\r
	316	//\r
	317	// Make sure the Timer Architectural Protocol is not already installed in the system\r
	318	//\r
	319	ASSERT_PROTOCOL_ALREADY_INSTALLED (NULL, &gEfiTimerArchProtocolGuid);\r
	320	\r
	321	//\r
	322	// Get the CPU Architectural Protocol instance\r
	323	//\r
	324	Status = gBS->LocateProtocol (&gEfiCpuArchProtocolGuid, NULL, (void *)&mCpu);\r
	325	ASSERT_EFI_ERROR (Status);\r
	326	\r
1ef41207	327	//\r
	328	// Start the timer thread at the default timer period\r
	329	//\r
	330	Status = mTimer.SetTimerPeriod (&mTimer, DEFAULT_TIMER_TICK_DURATION);\r
	331	if (EFI_ERROR (Status)) {\r
	332	return Status;\r
	333	}\r
	334	\r
949f388f	335	//\r
	336	// Install the Timer Architectural Protocol onto a new handle\r
	337	//\r
	338	Handle = NULL;\r
	339	Status = gBS->InstallProtocolInterface (\r
	340	&Handle,\r
	341	&gEfiTimerArchProtocolGuid,\r
	342	EFI_NATIVE_INTERFACE,\r
	343	&mTimer\r
	344	);\r
	345	if (EFI_ERROR (Status)) {\r
	346	return Status;\r
	347	}\r
	348	\r
949f388f	349	return EFI_SUCCESS;\r
949f388f	350	}\r