[mirror_edk2.git] / Omap35xxPkg / TimerDxe / Timer.c

/** @file\r
  Template for Timer Architecture Protocol driver of the ARM flavor\r
\r
  Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>\r
\r
  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
#include <PiDxe.h>\r
\r
#include <Library/BaseLib.h>\r
#include <Library/DebugLib.h>\r
#include <Library/BaseMemoryLib.h>\r
#include <Library/UefiBootServicesTableLib.h>\r
#include <Library/UefiLib.h>\r
#include <Library/PcdLib.h>\r
#include <Library/IoLib.h>\r
#include <Library/OmapLib.h>\r
\r
#include <Protocol/Timer.h>\r
#include <Protocol/HardwareInterrupt.h>\r
\r
#include <Omap3530/Omap3530.h>\r
\r
\r
// The notification function to call on every timer interrupt.\r
volatile EFI_TIMER_NOTIFY      mTimerNotifyFunction   = (EFI_TIMER_NOTIFY)NULL;\r
\r
\r
// The current period of the timer interrupt\r
volatile UINT64 mTimerPeriod = 0;\r
\r
// Cached copy of the Hardware Interrupt protocol instance\r
EFI_HARDWARE_INTERRUPT_PROTOCOL *gInterrupt = NULL;\r
\r
// Cached registers\r
volatile UINT32 TISR;\r
volatile UINT32 TCLR;\r
volatile UINT32 TLDR;\r
volatile UINT32 TCRR;\r
volatile UINT32 TIER;\r
\r
// Cached interrupt vector\r
volatile UINTN  gVector;\r
\r
\r
/**\r
\r
  C Interrupt Handler calledin the interrupt context when Source interrupt is active.\r
\r
\r
  @param Source         Source of the interrupt. Hardware routing off a specific platform defines\r
                        what source means.\r
\r
  @param SystemContext  Pointer to system register context. Mostly used by debuggers and will\r
                        update the system context after the return from the interrupt if\r
                        modified. Don't change these values unless you know what you are doing\r
\r
**/\r
VOID\r
EFIAPI\r
TimerInterruptHandler (\r
  IN  HARDWARE_INTERRUPT_SOURCE   Source,\r
  IN  EFI_SYSTEM_CONTEXT          SystemContext\r
  )\r
{\r
  EFI_TPL OriginalTPL;\r
\r
\r
\r
  //\r
  // DXE core uses this callback for the EFI timer tick. The DXE core uses locks\r
  // that raise to TPL_HIGH and then restore back to current level. Thus we need\r
  // to make sure TPL level is set to TPL_HIGH while we are handling the timer tick.\r
  //\r
  OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);\r
\r
  if (mTimerNotifyFunction) {\r
    mTimerNotifyFunction(mTimerPeriod);\r
  }\r
\r
  // Clear all timer interrupts\r
  MmioWrite32 (TISR, TISR_CLEAR_ALL);\r
\r
  // Poll interrupt status bits to ensure clearing\r
  while ((MmioRead32 (TISR) & TISR_ALL_INTERRUPT_MASK) != TISR_NO_INTERRUPTS_PENDING);\r
\r
  gBS->RestoreTPL (OriginalTPL);\r
}\r
\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
  @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.\r
  @param  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
  @retval EFI_SUCCESS           The timer handler was registered.\r
  @retval EFI_UNSUPPORTED       The platform does not support timer interrupts.\r
  @retval EFI_ALREADY_STARTED   NotifyFunction is not NULL, and a handler is already\r
                                registered.\r
  @retval EFI_INVALID_PARAMETER NotifyFunction is NULL, and a handler was not\r
                                previously registered.\r
  @retval EFI_DEVICE_ERROR      The timer handler could not be registered.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
TimerDriverRegisterHandler (\r
  IN EFI_TIMER_ARCH_PROTOCOL  *This,\r
  IN EFI_TIMER_NOTIFY         NotifyFunction\r
  )\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
  mTimerNotifyFunction = NotifyFunction;\r
\r
  return EFI_SUCCESS;\r
}\r
\r
/**\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
  @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.\r
  @param  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
\r
  @retval EFI_SUCCESS           The timer period was changed.\r
  @retval EFI_UNSUPPORTED       The platform cannot change the period of the timer interrupt.\r
  @retval EFI_DEVICE_ERROR      The timer period could not be changed due to a device error.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
TimerDriverSetTimerPeriod (\r
  IN EFI_TIMER_ARCH_PROTOCOL  *This,\r
  IN UINT64                   TimerPeriod\r
  )\r
{\r
  EFI_STATUS  Status;\r
  UINT64      TimerCount;\r
  INT32       LoadValue;\r
\r
  if (TimerPeriod == 0) {\r
    // Turn off GPTIMER3\r
    MmioWrite32 (TCLR, TCLR_ST_OFF);\r
\r
    Status = gInterrupt->DisableInterruptSource(gInterrupt, gVector);\r
  } else {\r
    // Calculate required timer count\r
    TimerCount = DivU64x32(TimerPeriod * 100, PcdGet32(PcdEmbeddedPerformanceCounterPeriodInNanoseconds));\r
\r
    // Set GPTIMER3 Load register\r
    LoadValue = (INT32) -TimerCount;\r
    MmioWrite32 (TLDR, LoadValue);\r
    MmioWrite32 (TCRR, LoadValue);\r
\r
    // Enable Overflow interrupt\r
    MmioWrite32 (TIER, TIER_TCAR_IT_DISABLE | TIER_OVF_IT_ENABLE | TIER_MAT_IT_DISABLE);\r
\r
    // Turn on GPTIMER3, it will reload at overflow\r
    MmioWrite32 (TCLR, TCLR_AR_AUTORELOAD | TCLR_ST_ON);\r
\r
    Status = gInterrupt->EnableInterruptSource(gInterrupt, gVector);\r
  }\r
\r
  //\r
  // Save the new timer period\r
  //\r
  mTimerPeriod = TimerPeriod;\r
  return Status;\r
}\r
\r
\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
  @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.\r
  @param  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
\r
  @retval EFI_SUCCESS           The timer period was returned in TimerPeriod.\r
  @retval EFI_INVALID_PARAMETER TimerPeriod is NULL.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
TimerDriverGetTimerPeriod (\r
  IN EFI_TIMER_ARCH_PROTOCOL   *This,\r
  OUT UINT64                   *TimerPeriod\r
  )\r
{\r
  if (TimerPeriod == NULL) {\r
    return EFI_INVALID_PARAMETER;\r
  }\r
\r
  *TimerPeriod = mTimerPeriod;\r
  return EFI_SUCCESS;\r
}\r
\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
  @param  This             The EFI_TIMER_ARCH_PROTOCOL instance.\r
\r
  @retval EFI_SUCCESS           The soft timer interrupt was generated.\r
  @retval EFI_UNSUPPORTED       The platform does not support the generation of soft timer interrupts.\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
TimerDriverGenerateSoftInterrupt (\r
  IN EFI_TIMER_ARCH_PROTOCOL  *This\r
  )\r
{\r
  return EFI_UNSUPPORTED;\r
}\r
\r
\r
/**\r
  Interface stucture for the Timer Architectural Protocol.\r
\r
  @par Protocol Description:\r
  This protocol provides the services to initialize a periodic timer\r
  interrupt, and to register a handler that is called each time the timer\r
  interrupt fires.  It may also provide a service to adjust the rate of the\r
  periodic timer interrupt.  When a timer interrupt occurs, the handler is\r
  passed the amount of time that has passed since the previous timer\r
  interrupt.\r
\r
  @param RegisterHandler\r
  Registers a handler that will be called each time the\r
  timer interrupt fires.  TimerPeriod defines the minimum\r
  time between timer interrupts, so TimerPeriod will also\r
  be the minimum time between calls to the registered\r
  handler.\r
\r
  @param SetTimerPeriod\r
  Sets the period of the timer interrupt in 100 nS units.\r
  This function is optional, and may return EFI_UNSUPPORTED.\r
  If this function is supported, then the timer period will\r
  be rounded up to the nearest supported timer period.\r
\r
\r
  @param GetTimerPeriod\r
  Retrieves the period of the timer interrupt in 100 nS units.\r
\r
  @param GenerateSoftInterrupt\r
  Generates a soft timer interrupt that simulates the firing of\r
  the timer interrupt. This service can be used to invoke the   registered handler if the timer interrupt has been masked for\r
  a period of time.\r
\r
**/\r
EFI_TIMER_ARCH_PROTOCOL   gTimer = {\r
  TimerDriverRegisterHandler,\r
  TimerDriverSetTimerPeriod,\r
  TimerDriverGetTimerPeriod,\r
  TimerDriverGenerateSoftInterrupt\r
};\r
\r
\r
/**\r
  Initialize the state information for the Timer Architectural Protocol and\r
  the Timer Debug support protocol that allows the debugger to break into a\r
  running program.\r
\r
  @param  ImageHandle   of the loaded driver\r
  @param  SystemTable   Pointer to the System Table\r
\r
  @retval EFI_SUCCESS           Protocol registered\r
  @retval EFI_OUT_OF_RESOURCES  Cannot allocate protocol data structure\r
  @retval EFI_DEVICE_ERROR      Hardware problems\r
\r
**/\r
EFI_STATUS\r
EFIAPI\r
TimerInitialize (\r
  IN EFI_HANDLE         ImageHandle,\r
  IN EFI_SYSTEM_TABLE   *SystemTable\r
  )\r
{\r
  EFI_HANDLE  Handle = NULL;\r
  EFI_STATUS  Status;\r
  UINT32      TimerBaseAddress;\r
\r
  // Find the interrupt controller protocol.  ASSERT if not found.\r
  Status = gBS->LocateProtocol (&gHardwareInterruptProtocolGuid, NULL, (VOID **)&gInterrupt);\r
  ASSERT_EFI_ERROR (Status);\r
\r
  // Set up the timer registers\r
  TimerBaseAddress = TimerBase (FixedPcdGet32(PcdOmap35xxArchTimer));\r
  TISR = TimerBaseAddress + GPTIMER_TISR;\r
  TCLR = TimerBaseAddress + GPTIMER_TCLR;\r
  TLDR = TimerBaseAddress + GPTIMER_TLDR;\r
  TCRR = TimerBaseAddress + GPTIMER_TCRR;\r
  TIER = TimerBaseAddress + GPTIMER_TIER;\r
\r
  // Disable the timer\r
  Status = TimerDriverSetTimerPeriod (&gTimer, 0);\r
  ASSERT_EFI_ERROR (Status);\r
\r
  // Install interrupt handler\r
  gVector = InterruptVectorForTimer (FixedPcdGet32(PcdOmap35xxArchTimer));\r
  Status = gInterrupt->RegisterInterruptSource (gInterrupt, gVector, TimerInterruptHandler);\r
  ASSERT_EFI_ERROR (Status);\r
\r
  // Turn on the functional clock for Timer\r
  MmioOr32 (CM_FCLKEN_PER, CM_FCLKEN_PER_EN_GPT3_ENABLE);\r
\r
  // Set up default timer\r
  Status = TimerDriverSetTimerPeriod (&gTimer, FixedPcdGet32(PcdTimerPeriod));\r
  ASSERT_EFI_ERROR (Status);\r
\r
  // Install the Timer Architectural Protocol onto a new handle\r
  Status = gBS->InstallMultipleProtocolInterfaces (\r
                  &Handle,\r
                  &gEfiTimerArchProtocolGuid,      &gTimer,\r
                  NULL\r
                  );\r
  ASSERT_EFI_ERROR(Status);\r
\r
  return Status;\r
}\r
\r
Commit	Line	Data
1e57a462	1	/** @file\r
	2	Template for Timer Architecture Protocol driver of the ARM flavor\r
	3	\r
	4	Copyright (c) 2008 - 2009, Apple Inc. All rights reserved.<BR>\r
1e57a462	5	\r
3402aac7 RC	6	This program and the accompanying materials\r
	7	are licensed and made available under the terms and conditions of the BSD License\r
	8	which accompanies this distribution. The full text of the license may be found at\r
	9	http://opensource.org/licenses/bsd-license.php\r
	10	\r
	11	THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
	12	WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.\r
1e57a462	13	\r
	14	**/\r
	15	\r
	16	\r
	17	#include <PiDxe.h>\r
	18	\r
	19	#include <Library/BaseLib.h>\r
	20	#include <Library/DebugLib.h>\r
	21	#include <Library/BaseMemoryLib.h>\r
	22	#include <Library/UefiBootServicesTableLib.h>\r
	23	#include <Library/UefiLib.h>\r
	24	#include <Library/PcdLib.h>\r
	25	#include <Library/IoLib.h>\r
	26	#include <Library/OmapLib.h>\r
	27	\r
	28	#include <Protocol/Timer.h>\r
	29	#include <Protocol/HardwareInterrupt.h>\r
	30	\r
	31	#include <Omap3530/Omap3530.h>\r
	32	\r
	33	\r
	34	// The notification function to call on every timer interrupt.\r
	35	volatile EFI_TIMER_NOTIFY mTimerNotifyFunction = (EFI_TIMER_NOTIFY)NULL;\r
	36	\r
	37	\r
	38	// The current period of the timer interrupt\r
	39	volatile UINT64 mTimerPeriod = 0;\r
	40	\r
	41	// Cached copy of the Hardware Interrupt protocol instance\r
	42	EFI_HARDWARE_INTERRUPT_PROTOCOL *gInterrupt = NULL;\r
	43	\r
	44	// Cached registers\r
	45	volatile UINT32 TISR;\r
	46	volatile UINT32 TCLR;\r
	47	volatile UINT32 TLDR;\r
	48	volatile UINT32 TCRR;\r
	49	volatile UINT32 TIER;\r
	50	\r
	51	// Cached interrupt vector\r
	52	volatile UINTN gVector;\r
	53	\r
	54	\r
	55	/**\r
	56	\r
	57	C Interrupt Handler calledin the interrupt context when Source interrupt is active.\r
	58	\r
	59	\r
	60	@param Source Source of the interrupt. Hardware routing off a specific platform defines\r
	61	what source means.\r
	62	\r
	63	@param SystemContext Pointer to system register context. Mostly used by debuggers and will\r
3402aac7	64	update the system context after the return from the interrupt if\r
1e57a462	65	modified. Don't change these values unless you know what you are doing\r
	66	\r
	67	**/\r
	68	VOID\r
	69	EFIAPI\r
	70	TimerInterruptHandler (\r
	71	IN HARDWARE_INTERRUPT_SOURCE Source,\r
3402aac7	72	IN EFI_SYSTEM_CONTEXT SystemContext\r
1e57a462	73	)\r
	74	{\r
	75	EFI_TPL OriginalTPL;\r
	76	\r
	77	\r
	78	\r
	79	//\r
3402aac7	80	// DXE core uses this callback for the EFI timer tick. The DXE core uses locks\r
1e57a462	81	// that raise to TPL_HIGH and then restore back to current level. Thus we need\r
3402aac7	82	// to make sure TPL level is set to TPL_HIGH while we are handling the timer tick.\r
1e57a462	83	//\r
	84	OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);\r
	85	\r
	86	if (mTimerNotifyFunction) {\r
	87	mTimerNotifyFunction(mTimerPeriod);\r
	88	}\r
	89	\r
	90	// Clear all timer interrupts\r
3402aac7	91	MmioWrite32 (TISR, TISR_CLEAR_ALL);\r
1e57a462	92	\r
	93	// Poll interrupt status bits to ensure clearing\r
	94	while ((MmioRead32 (TISR) & TISR_ALL_INTERRUPT_MASK) != TISR_NO_INTERRUPTS_PENDING);\r
	95	\r
	96	gBS->RestoreTPL (OriginalTPL);\r
	97	}\r
	98	\r
	99	/**\r
3402aac7 RC	100	This function registers the handler NotifyFunction so it is called every time\r
	101	the timer interrupt fires. It also passes the amount of time since the last\r
	102	handler call to the NotifyFunction. If NotifyFunction is NULL, then the\r
	103	handler is unregistered. If the handler is registered, then EFI_SUCCESS is\r
	104	returned. If the CPU does not support registering a timer interrupt handler,\r
	105	then EFI_UNSUPPORTED is returned. If an attempt is made to register a handler\r
	106	when a handler is already registered, then EFI_ALREADY_STARTED is returned.\r
	107	If an attempt is made to unregister a handler when a handler is not registered,\r
	108	then EFI_INVALID_PARAMETER is returned. If an error occurs attempting to\r
	109	register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR\r
1e57a462	110	is returned.\r
	111	\r
	112	@param This The EFI_TIMER_ARCH_PROTOCOL instance.\r
	113	@param NotifyFunction The function to call when a timer interrupt fires. This\r
	114	function executes at TPL_HIGH_LEVEL. The DXE Core will\r
	115	register a handler for the timer interrupt, so it can know\r
	116	how much time has passed. This information is used to\r
	117	signal timer based events. NULL will unregister the handler.\r
	118	@retval EFI_SUCCESS The timer handler was registered.\r
	119	@retval EFI_UNSUPPORTED The platform does not support timer interrupts.\r
	120	@retval EFI_ALREADY_STARTED NotifyFunction is not NULL, and a handler is already\r
	121	registered.\r
	122	@retval EFI_INVALID_PARAMETER NotifyFunction is NULL, and a handler was not\r
	123	previously registered.\r
	124	@retval EFI_DEVICE_ERROR The timer handler could not be registered.\r
	125	\r
	126	**/\r
	127	EFI_STATUS\r
	128	EFIAPI\r
	129	TimerDriverRegisterHandler (\r
	130	IN EFI_TIMER_ARCH_PROTOCOL *This,\r
	131	IN EFI_TIMER_NOTIFY NotifyFunction\r
	132	)\r
	133	{\r
	134	if ((NotifyFunction == NULL) && (mTimerNotifyFunction == NULL)) {\r
	135	return EFI_INVALID_PARAMETER;\r
	136	}\r
	137	\r
	138	if ((NotifyFunction != NULL) && (mTimerNotifyFunction != NULL)) {\r
	139	return EFI_ALREADY_STARTED;\r
	140	}\r
	141	\r
	142	mTimerNotifyFunction = NotifyFunction;\r
	143	\r
	144	return EFI_SUCCESS;\r
	145	}\r
	146	\r
	147	/**\r
	148	\r
3402aac7 RC	149	This function adjusts the period of timer interrupts to the value specified\r
	150	by TimerPeriod. If the timer period is updated, then the selected timer\r
	151	period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned. If\r
	152	the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.\r
	153	If an error occurs while attempting to update the timer period, then the\r
	154	timer hardware will be put back in its state prior to this call, and\r
	155	EFI_DEVICE_ERROR is returned. If TimerPeriod is 0, then the timer interrupt\r
	156	is disabled. This is not the same as disabling the CPU's interrupts.\r
	157	Instead, it must either turn off the timer hardware, or it must adjust the\r
	158	interrupt controller so that a CPU interrupt is not generated when the timer\r
	159	interrupt fires.\r
1e57a462	160	\r
	161	@param This The EFI_TIMER_ARCH_PROTOCOL instance.\r
	162	@param TimerPeriod The rate to program the timer interrupt in 100 nS units. If\r
	163	the timer hardware is not programmable, then EFI_UNSUPPORTED is\r
	164	returned. If the timer is programmable, then the timer period\r
	165	will be rounded up to the nearest timer period that is supported\r
	166	by the timer hardware. If TimerPeriod is set to 0, then the\r
	167	timer interrupts will be disabled.\r
	168	\r
	169	\r
	170	@retval EFI_SUCCESS The timer period was changed.\r
	171	@retval EFI_UNSUPPORTED The platform cannot change the period of the timer interrupt.\r
	172	@retval EFI_DEVICE_ERROR The timer period could not be changed due to a device error.\r
	173	\r
	174	**/\r
	175	EFI_STATUS\r
	176	EFIAPI\r
	177	TimerDriverSetTimerPeriod (\r
	178	IN EFI_TIMER_ARCH_PROTOCOL *This,\r
	179	IN UINT64 TimerPeriod\r
	180	)\r
	181	{\r
	182	EFI_STATUS Status;\r
	183	UINT64 TimerCount;\r
	184	INT32 LoadValue;\r
3402aac7	185	\r
1e57a462	186	if (TimerPeriod == 0) {\r
	187	// Turn off GPTIMER3\r
	188	MmioWrite32 (TCLR, TCLR_ST_OFF);\r
3402aac7 RC	189	\r
	190	Status = gInterrupt->DisableInterruptSource(gInterrupt, gVector);\r
	191	} else {\r
1e57a462	192	// Calculate required timer count\r
	193	TimerCount = DivU64x32(TimerPeriod * 100, PcdGet32(PcdEmbeddedPerformanceCounterPeriodInNanoseconds));\r
	194	\r
	195	// Set GPTIMER3 Load register\r
	196	LoadValue = (INT32) -TimerCount;\r
	197	MmioWrite32 (TLDR, LoadValue);\r
	198	MmioWrite32 (TCRR, LoadValue);\r
	199	\r
	200	// Enable Overflow interrupt\r
	201	MmioWrite32 (TIER, TIER_TCAR_IT_DISABLE \| TIER_OVF_IT_ENABLE \| TIER_MAT_IT_DISABLE);\r
	202	\r
	203	// Turn on GPTIMER3, it will reload at overflow\r
	204	MmioWrite32 (TCLR, TCLR_AR_AUTORELOAD \| TCLR_ST_ON);\r
	205	\r
3402aac7	206	Status = gInterrupt->EnableInterruptSource(gInterrupt, gVector);\r
1e57a462	207	}\r
	208	\r
	209	//\r
	210	// Save the new timer period\r
	211	//\r
	212	mTimerPeriod = TimerPeriod;\r
	213	return Status;\r
	214	}\r
	215	\r
	216	\r
	217	/**\r
3402aac7 RC	218	This function retrieves the period of timer interrupts in 100 ns units,\r
	219	returns that value in TimerPeriod, and returns EFI_SUCCESS. If TimerPeriod\r
	220	is NULL, then EFI_INVALID_PARAMETER is returned. If a TimerPeriod of 0 is\r
1e57a462	221	returned, then the timer is currently disabled.\r
	222	\r
	223	@param This The EFI_TIMER_ARCH_PROTOCOL instance.\r
	224	@param TimerPeriod A pointer to the timer period to retrieve in 100 ns units. If\r
	225	0 is returned, then the timer is currently disabled.\r
	226	\r
	227	\r
	228	@retval EFI_SUCCESS The timer period was returned in TimerPeriod.\r
	229	@retval EFI_INVALID_PARAMETER TimerPeriod is NULL.\r
	230	\r
	231	**/\r
	232	EFI_STATUS\r
	233	EFIAPI\r
	234	TimerDriverGetTimerPeriod (\r
	235	IN EFI_TIMER_ARCH_PROTOCOL *This,\r
	236	OUT UINT64 *TimerPeriod\r
	237	)\r
	238	{\r
	239	if (TimerPeriod == NULL) {\r
	240	return EFI_INVALID_PARAMETER;\r
	241	}\r
	242	\r
	243	*TimerPeriod = mTimerPeriod;\r
	244	return EFI_SUCCESS;\r
	245	}\r
	246	\r
	247	/**\r
3402aac7 RC	248	This function generates a soft timer interrupt. If the platform does not support soft\r
	249	timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned.\r
	250	If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler()\r
	251	service, then a soft timer interrupt will be generated. If the timer interrupt is\r
	252	enabled when this service is called, then the registered handler will be invoked. The\r
	253	registered handler should not be able to distinguish a hardware-generated timer\r
1e57a462	254	interrupt from a software-generated timer interrupt.\r
	255	\r
	256	@param This The EFI_TIMER_ARCH_PROTOCOL instance.\r
	257	\r
	258	@retval EFI_SUCCESS The soft timer interrupt was generated.\r
	259	@retval EFI_UNSUPPORTED The platform does not support the generation of soft timer interrupts.\r
	260	\r
	261	**/\r
	262	EFI_STATUS\r
	263	EFIAPI\r
	264	TimerDriverGenerateSoftInterrupt (\r
	265	IN EFI_TIMER_ARCH_PROTOCOL *This\r
	266	)\r
	267	{\r
	268	return EFI_UNSUPPORTED;\r
	269	}\r
	270	\r
	271	\r
	272	/**\r
	273	Interface stucture for the Timer Architectural Protocol.\r
	274	\r
	275	@par Protocol Description:\r
3402aac7	276	This protocol provides the services to initialize a periodic timer\r
1e57a462	277	interrupt, and to register a handler that is called each time the timer\r
1e57a462	278	interrupt fires. It may also provide a service to adjust the rate of the\r
3402aac7 RC	279	periodic timer interrupt. When a timer interrupt occurs, the handler is\r
3402aac7 RC	280	passed the amount of time that has passed since the previous timer\r
1e57a462	281	interrupt.\r
	282	\r
	283	@param RegisterHandler\r
3402aac7 RC	284	Registers a handler that will be called each time the\r
	285	timer interrupt fires. TimerPeriod defines the minimum\r
	286	time between timer interrupts, so TimerPeriod will also\r
	287	be the minimum time between calls to the registered\r
1e57a462	288	handler.\r
	289	\r
	290	@param SetTimerPeriod\r
3402aac7 RC	291	Sets the period of the timer interrupt in 100 nS units.\r
	292	This function is optional, and may return EFI_UNSUPPORTED.\r
	293	If this function is supported, then the timer period will\r
1e57a462	294	be rounded up to the nearest supported timer period.\r
	295	\r
	296	\r
	297	@param GetTimerPeriod\r
	298	Retrieves the period of the timer interrupt in 100 nS units.\r
	299	\r
	300	@param GenerateSoftInterrupt\r
3402aac7 RC	301	Generates a soft timer interrupt that simulates the firing of\r
3402aac7 RC	302	the timer interrupt. This service can be used to invoke the registered handler if the timer interrupt has been masked for\r
1e57a462	303	a period of time.\r
	304	\r
	305	**/\r
	306	EFI_TIMER_ARCH_PROTOCOL gTimer = {\r
	307	TimerDriverRegisterHandler,\r
	308	TimerDriverSetTimerPeriod,\r
	309	TimerDriverGetTimerPeriod,\r
	310	TimerDriverGenerateSoftInterrupt\r
	311	};\r
	312	\r
	313	\r
	314	/**\r
	315	Initialize the state information for the Timer Architectural Protocol and\r
	316	the Timer Debug support protocol that allows the debugger to break into a\r
	317	running program.\r
	318	\r
	319	@param ImageHandle of the loaded driver\r
	320	@param SystemTable Pointer to the System Table\r
	321	\r
	322	@retval EFI_SUCCESS Protocol registered\r
	323	@retval EFI_OUT_OF_RESOURCES Cannot allocate protocol data structure\r
	324	@retval EFI_DEVICE_ERROR Hardware problems\r
	325	\r
	326	**/\r
	327	EFI_STATUS\r
	328	EFIAPI\r
	329	TimerInitialize (\r
	330	IN EFI_HANDLE ImageHandle,\r
	331	IN EFI_SYSTEM_TABLE *SystemTable\r
	332	)\r
	333	{\r
	334	EFI_HANDLE Handle = NULL;\r
	335	EFI_STATUS Status;\r
	336	UINT32 TimerBaseAddress;\r
	337	\r
	338	// Find the interrupt controller protocol. ASSERT if not found.\r
	339	Status = gBS->LocateProtocol (&gHardwareInterruptProtocolGuid, NULL, (VOID **)&gInterrupt);\r
	340	ASSERT_EFI_ERROR (Status);\r
	341	\r
	342	// Set up the timer registers\r
	343	TimerBaseAddress = TimerBase (FixedPcdGet32(PcdOmap35xxArchTimer));\r
	344	TISR = TimerBaseAddress + GPTIMER_TISR;\r
	345	TCLR = TimerBaseAddress + GPTIMER_TCLR;\r
	346	TLDR = TimerBaseAddress + GPTIMER_TLDR;\r
	347	TCRR = TimerBaseAddress + GPTIMER_TCRR;\r
	348	TIER = TimerBaseAddress + GPTIMER_TIER;\r
	349	\r
	350	// Disable the timer\r
	351	Status = TimerDriverSetTimerPeriod (&gTimer, 0);\r
	352	ASSERT_EFI_ERROR (Status);\r
	353	\r
	354	// Install interrupt handler\r
	355	gVector = InterruptVectorForTimer (FixedPcdGet32(PcdOmap35xxArchTimer));\r
	356	Status = gInterrupt->RegisterInterruptSource (gInterrupt, gVector, TimerInterruptHandler);\r
	357	ASSERT_EFI_ERROR (Status);\r
	358	\r
	359	// Turn on the functional clock for Timer\r
	360	MmioOr32 (CM_FCLKEN_PER, CM_FCLKEN_PER_EN_GPT3_ENABLE);\r
	361	\r
	362	// Set up default timer\r
	363	Status = TimerDriverSetTimerPeriod (&gTimer, FixedPcdGet32(PcdTimerPeriod));\r
	364	ASSERT_EFI_ERROR (Status);\r
	365	\r
	366	// Install the Timer Architectural Protocol onto a new handle\r
367	Status = gBS->InstallMultipleProtocolInterfaces (\r
368	&Handle,\r
369	&gEfiTimerArchProtocolGuid, &gTimer,\r
370	NULL\r
371	);\r
372	ASSERT_EFI_ERROR(Status);\r
373	\r
374	return Status;\r
375	}\r
376	\r