[mirror_edk2.git] / ArmPkg / Drivers / TimerDxe / TimerDxe.c

/** @file\r
  Timer Architecture Protocol driver of the ARM flavor\r
\r
  Copyright (c) 2011-2013 ARM Ltd. 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/ArmLib.h>\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/ArmArchTimerLib.h>\r
\r
#include <Protocol/Timer.h>\r
#include <Protocol/HardwareInterrupt.h>\r
\r
// The notification function to call on every timer interrupt.\r
EFI_TIMER_NOTIFY      mTimerNotifyFunction     = (EFI_TIMER_NOTIFY)NULL;\r
EFI_EVENT             EfiExitBootServicesEvent = (EFI_EVENT)NULL;\r
\r
// The current period of the timer interrupt\r
UINT64 mTimerPeriod = 0;\r
\r
// Cached copy of the Hardware Interrupt protocol instance\r
EFI_HARDWARE_INTERRUPT_PROTOCOL *gInterrupt = NULL;\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
    Disable the timer\r
**/\r
VOID\r
EFIAPI\r
ExitBootServicesEvent (\r
  IN EFI_EVENT  Event,\r
  IN VOID       *Context\r
  )\r
{\r
  ArmArchTimerDisableTimer ();\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
  UINT64      TimerTicks;\r
  \r
  // Always disable the timer\r
  ArmArchTimerDisableTimer ();\r
\r
  if (TimerPeriod != 0) {\r
    // Convert TimerPeriod to micro sec units\r
    TimerTicks = DivU64x32 (TimerPeriod, 10);\r
\r
    TimerTicks = MultU64x32 (TimerTicks, (PcdGet32(PcdArmArchTimerFreqInHz)/1000000));\r
\r
    ArmArchTimerSetTimerVal((UINTN)TimerTicks);\r
\r
    // Enable the timer\r
    ArmArchTimerEnableTimer ();\r
  }\r
\r
  // Save the new timer period\r
  mTimerPeriod = TimerPeriod;\r
  return EFI_SUCCESS;\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
  Interface structure 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
  C Interrupt Handler called in 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
  // 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
  // Check if the timer interrupt is active\r
  if ((ArmArchTimerGetTimerCtrlReg () ) & ARM_ARCH_TIMER_ISTATUS) {\r
\r
    // Signal end of interrupt early to help avoid losing subsequent ticks from long duration handlers\r
    gInterrupt->EndOfInterrupt (gInterrupt, Source);\r
\r
    if (mTimerNotifyFunction) {\r
      mTimerNotifyFunction (mTimerPeriod);\r
    }\r
\r
    // Reload the Timer\r
    TimerDriverSetTimerPeriod (&gTimer, FixedPcdGet32(PcdTimerPeriod));\r
  }\r
\r
  // Enable timer interrupts\r
  gInterrupt->EnableInterruptSource (gInterrupt, Source);\r
\r
  gBS->RestoreTPL (OriginalTPL);\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
  UINTN TimerCtrlReg;\r
\r
  if (ArmIsArchTimerImplemented () == 0) {\r
    DEBUG ((EFI_D_ERROR, "ARM Architectural Timer is not available in the CPU, hence cann't use this Driver \n"));\r
    ASSERT (0);\r
  }\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
  // Disable the timer\r
  TimerCtrlReg = ArmArchTimerGetTimerCtrlReg ();\r
  TimerCtrlReg |= ARM_ARCH_TIMER_IMASK;\r
  TimerCtrlReg &= ~ARM_ARCH_TIMER_ENABLE;\r
  ArmArchTimerSetTimerCtrlReg (TimerCtrlReg);\r
  Status = TimerDriverSetTimerPeriod (&gTimer, 0);\r
  ASSERT_EFI_ERROR (Status);\r
\r
  // Install secure and Non-secure interrupt handlers\r
  // Note: Because it is not possible to determine the security state of the\r
  // CPU dynamically, we just install interrupt handler for both sec and non-sec\r
  // timer PPI\r
  Status = gInterrupt->RegisterInterruptSource (gInterrupt, PcdGet32 (PcdArmArchTimerSecIntrNum), TimerInterruptHandler);\r
  ASSERT_EFI_ERROR (Status);\r
\r
  Status = gInterrupt->RegisterInterruptSource (gInterrupt, PcdGet32 (PcdArmArchTimerIntrNum), TimerInterruptHandler);\r
  ASSERT_EFI_ERROR (Status);\r
\r
  // Set up default timer\r
  Status = TimerDriverSetTimerPeriod (&gTimer, FixedPcdGet32(PcdTimerPeriod)); // TIMER_DEFAULT_PERIOD\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
  // Everything is ready, unmask and enable timer interrupts\r
  TimerCtrlReg = ARM_ARCH_TIMER_ENABLE;\r
  ArmArchTimerSetTimerCtrlReg (TimerCtrlReg);\r
\r
  // Register for an ExitBootServicesEvent\r
  Status = gBS->CreateEvent (EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_NOTIFY, ExitBootServicesEvent, NULL, &EfiExitBootServicesEvent);\r
  ASSERT_EFI_ERROR (Status);\r
\r
  return Status;\r
}\r
Commit	Line	Data
1e57a462	1	/** @file\r
	2	Timer Architecture Protocol driver of the ARM flavor\r
	3	\r
e703b085 OM	4	Copyright (c) 2011-2013 ARM Ltd. All rights reserved.<BR>\r
	5	\r
	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
1e57a462	10	\r
e703b085 OM	11	THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,\r
e703b085 OM	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/ArmLib.h>\r
	20	#include <Library/BaseLib.h>\r
	21	#include <Library/DebugLib.h>\r
	22	#include <Library/BaseMemoryLib.h>\r
	23	#include <Library/UefiBootServicesTableLib.h>\r
	24	#include <Library/UefiLib.h>\r
	25	#include <Library/PcdLib.h>\r
	26	#include <Library/IoLib.h>\r
25402f5d	27	#include <Library/ArmArchTimerLib.h>\r
1e57a462	28	\r
	29	#include <Protocol/Timer.h>\r
	30	#include <Protocol/HardwareInterrupt.h>\r
	31	\r
	32	// The notification function to call on every timer interrupt.\r
	33	EFI_TIMER_NOTIFY mTimerNotifyFunction = (EFI_TIMER_NOTIFY)NULL;\r
	34	EFI_EVENT EfiExitBootServicesEvent = (EFI_EVENT)NULL;\r
	35	\r
	36	// The current period of the timer interrupt\r
	37	UINT64 mTimerPeriod = 0;\r
	38	\r
	39	// Cached copy of the Hardware Interrupt protocol instance\r
	40	EFI_HARDWARE_INTERRUPT_PROTOCOL *gInterrupt = NULL;\r
	41	\r
	42	/**\r
	43	This function registers the handler NotifyFunction so it is called every time \r
	44	the timer interrupt fires. It also passes the amount of time since the last \r
	45	handler call to the NotifyFunction. If NotifyFunction is NULL, then the \r
	46	handler is unregistered. If the handler is registered, then EFI_SUCCESS is \r
	47	returned. If the CPU does not support registering a timer interrupt handler, \r
	48	then EFI_UNSUPPORTED is returned. If an attempt is made to register a handler \r
	49	when a handler is already registered, then EFI_ALREADY_STARTED is returned. \r
	50	If an attempt is made to unregister a handler when a handler is not registered, \r
	51	then EFI_INVALID_PARAMETER is returned. If an error occurs attempting to \r
	52	register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR \r
	53	is returned.\r
	54	\r
	55	@param This The EFI_TIMER_ARCH_PROTOCOL instance.\r
	56	@param NotifyFunction The function to call when a timer interrupt fires. This\r
	57	function executes at TPL_HIGH_LEVEL. The DXE Core will\r
	58	register a handler for the timer interrupt, so it can know\r
	59	how much time has passed. This information is used to\r
	60	signal timer based events. NULL will unregister the handler.\r
	61	@retval EFI_SUCCESS The timer handler was registered.\r
	62	@retval EFI_UNSUPPORTED The platform does not support timer interrupts.\r
	63	@retval EFI_ALREADY_STARTED NotifyFunction is not NULL, and a handler is already\r
	64	registered.\r
	65	@retval EFI_INVALID_PARAMETER NotifyFunction is NULL, and a handler was not\r
	66	previously registered.\r
	67	@retval EFI_DEVICE_ERROR The timer handler could not be registered.\r
	68	\r
	69	**/\r
	70	EFI_STATUS\r
	71	EFIAPI\r
	72	TimerDriverRegisterHandler (\r
	73	IN EFI_TIMER_ARCH_PROTOCOL *This,\r
	74	IN EFI_TIMER_NOTIFY NotifyFunction\r
	75	)\r
	76	{\r
	77	if ((NotifyFunction == NULL) && (mTimerNotifyFunction == NULL)) {\r
	78	return EFI_INVALID_PARAMETER;\r
	79	}\r
	80	\r
	81	if ((NotifyFunction != NULL) && (mTimerNotifyFunction != NULL)) {\r
	82	return EFI_ALREADY_STARTED;\r
	83	}\r
	84	\r
	85	mTimerNotifyFunction = NotifyFunction;\r
	86	\r
	87	return EFI_SUCCESS;\r
	88	}\r
	89	\r
	90	/**\r
	91	Disable the timer\r
92	**/\r
93	VOID\r
94	EFIAPI\r
95	ExitBootServicesEvent (\r
96	IN EFI_EVENT Event,\r
97	IN VOID *Context\r
98	)\r
99	{\r
100	ArmArchTimerDisableTimer ();\r
101	}\r
102	\r
103	/**\r
104	\r
105	This function adjusts the period of timer interrupts to the value specified \r
106	by TimerPeriod. If the timer period is updated, then the selected timer \r
107	period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned. If \r
108	the timer hardware is not programmable, then EFI_UNSUPPORTED is returned. \r
109	If an error occurs while attempting to update the timer period, then the \r
110	timer hardware will be put back in its state prior to this call, and \r
111	EFI_DEVICE_ERROR is returned. If TimerPeriod is 0, then the timer interrupt \r
112	is disabled. This is not the same as disabling the CPU's interrupts. \r
113	Instead, it must either turn off the timer hardware, or it must adjust the \r
114	interrupt controller so that a CPU interrupt is not generated when the timer \r
115	interrupt fires. \r
116	\r
117	@param This The EFI_TIMER_ARCH_PROTOCOL instance.\r
118	@param TimerPeriod The rate to program the timer interrupt in 100 nS units. If\r
119	the timer hardware is not programmable, then EFI_UNSUPPORTED is\r
120	returned. If the timer is programmable, then the timer period\r
121	will be rounded up to the nearest timer period that is supported\r
122	by the timer hardware. If TimerPeriod is set to 0, then the\r
123	timer interrupts will be disabled.\r
124	\r
125	\r
126	@retval EFI_SUCCESS The timer period was changed.\r
127	@retval EFI_UNSUPPORTED The platform cannot change the period of the timer interrupt.\r
128	@retval EFI_DEVICE_ERROR The timer period could not be changed due to a device error.\r
129	\r
130	**/\r
131	EFI_STATUS\r
132	EFIAPI\r
133	TimerDriverSetTimerPeriod (\r
134	IN EFI_TIMER_ARCH_PROTOCOL *This,\r
135	IN UINT64 TimerPeriod\r
136	)\r
137	{\r
138	UINT64 TimerTicks;\r
139	\r
140	// Always disable the timer\r
141	ArmArchTimerDisableTimer ();\r
142	\r
143	if (TimerPeriod != 0) {\r
144	// Convert TimerPeriod to micro sec units\r
145	TimerTicks = DivU64x32 (TimerPeriod, 10);\r
146	\r
147	TimerTicks = MultU64x32 (TimerTicks, (PcdGet32(PcdArmArchTimerFreqInHz)/1000000));\r
148	\r
149	ArmArchTimerSetTimerVal((UINTN)TimerTicks);\r
150	\r
151	// Enable the timer\r
152	ArmArchTimerEnableTimer ();\r
153	}\r
154	\r
155	// Save the new timer period\r
156	mTimerPeriod = TimerPeriod;\r
157	return EFI_SUCCESS;\r
158	}\r
159	\r
160	/**\r
161	This function retrieves the period of timer interrupts in 100 ns units, \r
162	returns that value in TimerPeriod, and returns EFI_SUCCESS. If TimerPeriod \r
163	is NULL, then EFI_INVALID_PARAMETER is returned. If a TimerPeriod of 0 is \r
164	returned, then the timer is currently disabled.\r
165	\r
166	@param This The EFI_TIMER_ARCH_PROTOCOL instance.\r
167	@param TimerPeriod A pointer to the timer period to retrieve in 100 ns units. If\r
168	0 is returned, then the timer is currently disabled.\r
169	\r
170	\r
171	@retval EFI_SUCCESS The timer period was returned in TimerPeriod.\r
172	@retval EFI_INVALID_PARAMETER TimerPeriod is NULL.\r
173	\r
174	**/\r
175	EFI_STATUS\r
176	EFIAPI\r
177	TimerDriverGetTimerPeriod (\r
178	IN EFI_TIMER_ARCH_PROTOCOL *This,\r
179	OUT UINT64 *TimerPeriod\r
180	)\r
181	{\r
182	if (TimerPeriod == NULL) {\r
183	return EFI_INVALID_PARAMETER;\r
184	}\r
185	\r
186	*TimerPeriod = mTimerPeriod;\r
187	return EFI_SUCCESS;\r
188	}\r
189	\r
190	/**\r
191	This function generates a soft timer interrupt. If the platform does not support soft \r
192	timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned. \r
193	If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler() \r
194	service, then a soft timer interrupt will be generated. If the timer interrupt is \r
195	enabled when this service is called, then the registered handler will be invoked. The \r
196	registered handler should not be able to distinguish a hardware-generated timer \r
197	interrupt from a software-generated timer interrupt.\r
198	\r
199	@param This The EFI_TIMER_ARCH_PROTOCOL instance.\r
200	\r
201	@retval EFI_SUCCESS The soft timer interrupt was generated.\r
202	@retval EFI_UNSUPPORTED The platform does not support the generation of soft timer interrupts.\r
203	\r
204	**/\r
205	EFI_STATUS\r
206	EFIAPI\r
207	TimerDriverGenerateSoftInterrupt (\r
208	IN EFI_TIMER_ARCH_PROTOCOL *This\r
209	)\r
210	{\r
211	return EFI_UNSUPPORTED;\r
212	}\r
213	\r
214	/**\r
215	Interface structure for the Timer Architectural Protocol.\r
216	\r
217	@par Protocol Description:\r
218	This protocol provides the services to initialize a periodic timer\r
219	interrupt, and to register a handler that is called each time the timer\r
220	interrupt fires. It may also provide a service to adjust the rate of the\r
221	periodic timer interrupt. When a timer interrupt occurs, the handler is\r
222	passed the amount of time that has passed since the previous timer\r
223	interrupt.\r
224	\r
225	@param RegisterHandler\r
226	Registers a handler that will be called each time the\r
227	timer interrupt fires. TimerPeriod defines the minimum\r
228	time between timer interrupts, so TimerPeriod will also\r
229	be the minimum time between calls to the registered\r
230	handler.\r
231	\r
232	@param SetTimerPeriod\r
233	Sets the period of the timer interrupt in 100 nS units.\r
234	This function is optional, and may return EFI_UNSUPPORTED.\r
235	If this function is supported, then the timer period will\r
236	be rounded up to the nearest supported timer period.\r
237	\r
238	\r
239	@param GetTimerPeriod\r
240	Retrieves the period of the timer interrupt in 100 nS units.\r
241	\r
242	@param GenerateSoftInterrupt\r
243	Generates a soft timer interrupt that simulates the firing of\r
244	the timer interrupt. This service can be used to invoke the registered handler if the timer interrupt has been masked for\r
245	a period of time.\r
246	\r
247	**/\r
248	EFI_TIMER_ARCH_PROTOCOL gTimer = {\r
249	TimerDriverRegisterHandler,\r
250	TimerDriverSetTimerPeriod,\r
251	TimerDriverGetTimerPeriod,\r
252	TimerDriverGenerateSoftInterrupt\r
253	};\r
254	\r
255	/**\r
256	\r
257	C Interrupt Handler called in the interrupt context when Source interrupt is active.\r
258	\r
259	\r
260	@param Source Source of the interrupt. Hardware routing off a specific platform defines\r
261	what source means.\r
262	\r
263	@param SystemContext Pointer to system register context. Mostly used by debuggers and will\r
264	update the system context after the return from the interrupt if\r
265	modified. Don't change these values unless you know what you are doing\r
266	\r
267	**/\r
268	VOID\r
269	EFIAPI\r
270	TimerInterruptHandler (\r
271	IN HARDWARE_INTERRUPT_SOURCE Source,\r
272	IN EFI_SYSTEM_CONTEXT SystemContext\r
273	)\r
274	{\r
275	EFI_TPL OriginalTPL;\r
276	\r
277	//\r
278	// DXE core uses this callback for the EFI timer tick. The DXE core uses locks\r
279	// that raise to TPL_HIGH and then restore back to current level. Thus we need\r
280	// to make sure TPL level is set to TPL_HIGH while we are handling the timer tick.\r
281	//\r
282	OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);\r
283	\r
284	// Check if the timer interrupt is active\r
285	if ((ArmArchTimerGetTimerCtrlReg () ) & ARM_ARCH_TIMER_ISTATUS) {\r
286	\r
287	// Signal end of interrupt early to help avoid losing subsequent ticks from long duration handlers\r
288	gInterrupt->EndOfInterrupt (gInterrupt, Source);\r
289	\r
290	if (mTimerNotifyFunction) {\r
291	mTimerNotifyFunction (mTimerPeriod);\r
292	}\r
293	\r
294	// Reload the Timer\r
295	TimerDriverSetTimerPeriod (&gTimer, FixedPcdGet32(PcdTimerPeriod));\r
296	}\r
297	\r
298	// Enable timer interrupts\r
299	gInterrupt->EnableInterruptSource (gInterrupt, Source);\r
300	\r
301	gBS->RestoreTPL (OriginalTPL);\r
302	}\r
303	\r
304	\r
305	/**\r
306	Initialize the state information for the Timer Architectural Protocol and\r
307	the Timer Debug support protocol that allows the debugger to break into a\r
308	running program.\r
309	\r
310	@param ImageHandle of the loaded driver\r
311	@param SystemTable Pointer to the System Table\r
312	\r
313	@retval EFI_SUCCESS Protocol registered\r
314	@retval EFI_OUT_OF_RESOURCES Cannot allocate protocol data structure\r
315	@retval EFI_DEVICE_ERROR Hardware problems\r
316	\r
317	**/\r
318	EFI_STATUS\r
319	EFIAPI\r
320	TimerInitialize (\r
321	IN EFI_HANDLE ImageHandle,\r
322	IN EFI_SYSTEM_TABLE *SystemTable\r
323	)\r
324	{\r
325	EFI_HANDLE Handle = NULL;\r
326	EFI_STATUS Status;\r
327	UINTN TimerCtrlReg;\r
328	\r
329	if (ArmIsArchTimerImplemented () == 0) {\r
330	DEBUG ((EFI_D_ERROR, "ARM Architectural Timer is not available in the CPU, hence cann't use this Driver \n"));\r
331	ASSERT (0);\r
332	}\r
333	\r
334	// Find the interrupt controller protocol. ASSERT if not found.\r
335	Status = gBS->LocateProtocol (&gHardwareInterruptProtocolGuid, NULL, (VOID **)&gInterrupt);\r
336	ASSERT_EFI_ERROR (Status);\r
337	\r
338	// Disable the timer\r
e703b085 OM	339	TimerCtrlReg = ArmArchTimerGetTimerCtrlReg ();\r
	340	TimerCtrlReg \|= ARM_ARCH_TIMER_IMASK;\r
	341	TimerCtrlReg &= ~ARM_ARCH_TIMER_ENABLE;\r
	342	ArmArchTimerSetTimerCtrlReg (TimerCtrlReg);\r
1e57a462	343	Status = TimerDriverSetTimerPeriod (&gTimer, 0);\r
	344	ASSERT_EFI_ERROR (Status);\r
	345	\r
	346	// Install secure and Non-secure interrupt handlers\r
	347	// Note: Because it is not possible to determine the security state of the\r
	348	// CPU dynamically, we just install interrupt handler for both sec and non-sec\r
	349	// timer PPI\r
	350	Status = gInterrupt->RegisterInterruptSource (gInterrupt, PcdGet32 (PcdArmArchTimerSecIntrNum), TimerInterruptHandler);\r
	351	ASSERT_EFI_ERROR (Status);\r
	352	\r
	353	Status = gInterrupt->RegisterInterruptSource (gInterrupt, PcdGet32 (PcdArmArchTimerIntrNum), TimerInterruptHandler);\r
	354	ASSERT_EFI_ERROR (Status);\r
	355	\r
1e57a462	356	// Set up default timer\r
	357	Status = TimerDriverSetTimerPeriod (&gTimer, FixedPcdGet32(PcdTimerPeriod)); // TIMER_DEFAULT_PERIOD\r
	358	ASSERT_EFI_ERROR (Status);\r
	359	\r
	360	// Install the Timer Architectural Protocol onto a new handle\r
	361	Status = gBS->InstallMultipleProtocolInterfaces(\r
	362	&Handle,\r
	363	&gEfiTimerArchProtocolGuid, &gTimer,\r
	364	NULL\r
	365	);\r
	366	ASSERT_EFI_ERROR(Status);\r
	367	\r
e703b085 OM	368	// Everything is ready, unmask and enable timer interrupts\r
	369	TimerCtrlReg = ARM_ARCH_TIMER_ENABLE;\r
	370	ArmArchTimerSetTimerCtrlReg (TimerCtrlReg);\r
1e57a462	371	\r
	372	// Register for an ExitBootServicesEvent\r
	373	Status = gBS->CreateEvent (EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_NOTIFY, ExitBootServicesEvent, NULL, &EfiExitBootServicesEvent);\r
	374	ASSERT_EFI_ERROR (Status);\r
	375	\r
	376	return Status;\r
	377	}\r