-/** @file
- Timer Architecture Protocol driver of the ARM flavor
-
- Copyright (c) 2011 ARM Ltd. All rights reserved.<BR>
-
- This program and the accompanying materials
- are licensed and made available under the terms and conditions of the BSD License
- which accompanies this distribution. The full text of the license may be found at
- http://opensource.org/licenses/bsd-license.php
-
- THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
- WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
-
-**/
-
-
-#include <PiDxe.h>
-
-#include <Library/ArmLib.h>
-#include <Library/BaseLib.h>
-#include <Library/DebugLib.h>
-#include <Library/BaseMemoryLib.h>
-#include <Library/UefiBootServicesTableLib.h>
-#include <Library/UefiLib.h>
-#include <Library/PcdLib.h>
-#include <Library/IoLib.h>
-#include <Library/ArmV7ArchTimerLib.h>
-
-#include <Protocol/Timer.h>
-#include <Protocol/HardwareInterrupt.h>
-
-// The notification function to call on every timer interrupt.
-EFI_TIMER_NOTIFY mTimerNotifyFunction = (EFI_TIMER_NOTIFY)NULL;
-EFI_EVENT EfiExitBootServicesEvent = (EFI_EVENT)NULL;
-
-// The current period of the timer interrupt
-UINT64 mTimerPeriod = 0;
-
-// Cached copy of the Hardware Interrupt protocol instance
-EFI_HARDWARE_INTERRUPT_PROTOCOL *gInterrupt = NULL;
-
-/**
- This function registers the handler NotifyFunction so it is called every time
- the timer interrupt fires. It also passes the amount of time since the last
- handler call to the NotifyFunction. If NotifyFunction is NULL, then the
- handler is unregistered. If the handler is registered, then EFI_SUCCESS is
- returned. If the CPU does not support registering a timer interrupt handler,
- then EFI_UNSUPPORTED is returned. If an attempt is made to register a handler
- when a handler is already registered, then EFI_ALREADY_STARTED is returned.
- If an attempt is made to unregister a handler when a handler is not registered,
- then EFI_INVALID_PARAMETER is returned. If an error occurs attempting to
- register the NotifyFunction with the timer interrupt, then EFI_DEVICE_ERROR
- is returned.
-
- @param This The EFI_TIMER_ARCH_PROTOCOL instance.
- @param NotifyFunction The function to call when a timer interrupt fires. This
- function executes at TPL_HIGH_LEVEL. The DXE Core will
- register a handler for the timer interrupt, so it can know
- how much time has passed. This information is used to
- signal timer based events. NULL will unregister the handler.
- @retval EFI_SUCCESS The timer handler was registered.
- @retval EFI_UNSUPPORTED The platform does not support timer interrupts.
- @retval EFI_ALREADY_STARTED NotifyFunction is not NULL, and a handler is already
- registered.
- @retval EFI_INVALID_PARAMETER NotifyFunction is NULL, and a handler was not
- previously registered.
- @retval EFI_DEVICE_ERROR The timer handler could not be registered.
-
-**/
-EFI_STATUS
-EFIAPI
-TimerDriverRegisterHandler (
- IN EFI_TIMER_ARCH_PROTOCOL *This,
- IN EFI_TIMER_NOTIFY NotifyFunction
- )
-{
- if ((NotifyFunction == NULL) && (mTimerNotifyFunction == NULL)) {
- return EFI_INVALID_PARAMETER;
- }
-
- if ((NotifyFunction != NULL) && (mTimerNotifyFunction != NULL)) {
- return EFI_ALREADY_STARTED;
- }
-
- mTimerNotifyFunction = NotifyFunction;
-
- return EFI_SUCCESS;
-}
-
-/**
- Disable the timer
-**/
-VOID
-EFIAPI
-ExitBootServicesEvent (
- IN EFI_EVENT Event,
- IN VOID *Context
- )
-{
- ArmArchTimerDisableTimer ();
-}
-
-/**
-
- This function adjusts the period of timer interrupts to the value specified
- by TimerPeriod. If the timer period is updated, then the selected timer
- period is stored in EFI_TIMER.TimerPeriod, and EFI_SUCCESS is returned. If
- the timer hardware is not programmable, then EFI_UNSUPPORTED is returned.
- If an error occurs while attempting to update the timer period, then the
- timer hardware will be put back in its state prior to this call, and
- EFI_DEVICE_ERROR is returned. If TimerPeriod is 0, then the timer interrupt
- is disabled. This is not the same as disabling the CPU's interrupts.
- Instead, it must either turn off the timer hardware, or it must adjust the
- interrupt controller so that a CPU interrupt is not generated when the timer
- interrupt fires.
-
- @param This The EFI_TIMER_ARCH_PROTOCOL instance.
- @param TimerPeriod The rate to program the timer interrupt in 100 nS units. If
- the timer hardware is not programmable, then EFI_UNSUPPORTED is
- returned. If the timer is programmable, then the timer period
- will be rounded up to the nearest timer period that is supported
- by the timer hardware. If TimerPeriod is set to 0, then the
- timer interrupts will be disabled.
-
-
- @retval EFI_SUCCESS The timer period was changed.
- @retval EFI_UNSUPPORTED The platform cannot change the period of the timer interrupt.
- @retval EFI_DEVICE_ERROR The timer period could not be changed due to a device error.
-
-**/
-EFI_STATUS
-EFIAPI
-TimerDriverSetTimerPeriod (
- IN EFI_TIMER_ARCH_PROTOCOL *This,
- IN UINT64 TimerPeriod
- )
-{
- UINT64 TimerTicks;
-
- // Always disable the timer
- ArmArchTimerDisableTimer ();
-
- if (TimerPeriod != 0) {
- // Convert TimerPeriod to micro sec units
- TimerTicks = DivU64x32 (TimerPeriod, 10);
-
- TimerTicks = MultU64x32 (TimerTicks, (PcdGet32(PcdArmArchTimerFreqInHz)/1000000));
-
- ArmArchTimerSetTimerVal((UINTN)TimerTicks);
-
- // Enable the timer
- ArmArchTimerEnableTimer ();
- }
-
- // Save the new timer period
- mTimerPeriod = TimerPeriod;
- return EFI_SUCCESS;
-}
-
-/**
- This function retrieves the period of timer interrupts in 100 ns units,
- returns that value in TimerPeriod, and returns EFI_SUCCESS. If TimerPeriod
- is NULL, then EFI_INVALID_PARAMETER is returned. If a TimerPeriod of 0 is
- returned, then the timer is currently disabled.
-
- @param This The EFI_TIMER_ARCH_PROTOCOL instance.
- @param TimerPeriod A pointer to the timer period to retrieve in 100 ns units. If
- 0 is returned, then the timer is currently disabled.
-
-
- @retval EFI_SUCCESS The timer period was returned in TimerPeriod.
- @retval EFI_INVALID_PARAMETER TimerPeriod is NULL.
-
-**/
-EFI_STATUS
-EFIAPI
-TimerDriverGetTimerPeriod (
- IN EFI_TIMER_ARCH_PROTOCOL *This,
- OUT UINT64 *TimerPeriod
- )
-{
- if (TimerPeriod == NULL) {
- return EFI_INVALID_PARAMETER;
- }
-
- *TimerPeriod = mTimerPeriod;
- return EFI_SUCCESS;
-}
-
-/**
- This function generates a soft timer interrupt. If the platform does not support soft
- timer interrupts, then EFI_UNSUPPORTED is returned. Otherwise, EFI_SUCCESS is returned.
- If a handler has been registered through the EFI_TIMER_ARCH_PROTOCOL.RegisterHandler()
- service, then a soft timer interrupt will be generated. If the timer interrupt is
- enabled when this service is called, then the registered handler will be invoked. The
- registered handler should not be able to distinguish a hardware-generated timer
- interrupt from a software-generated timer interrupt.
-
- @param This The EFI_TIMER_ARCH_PROTOCOL instance.
-
- @retval EFI_SUCCESS The soft timer interrupt was generated.
- @retval EFI_UNSUPPORTED The platform does not support the generation of soft timer interrupts.
-
-**/
-EFI_STATUS
-EFIAPI
-TimerDriverGenerateSoftInterrupt (
- IN EFI_TIMER_ARCH_PROTOCOL *This
- )
-{
- return EFI_UNSUPPORTED;
-}
-
-/**
- Interface structure for the Timer Architectural Protocol.
-
- @par Protocol Description:
- This protocol provides the services to initialize a periodic timer
- interrupt, and to register a handler that is called each time the timer
- interrupt fires. It may also provide a service to adjust the rate of the
- periodic timer interrupt. When a timer interrupt occurs, the handler is
- passed the amount of time that has passed since the previous timer
- interrupt.
-
- @param RegisterHandler
- Registers a handler that will be called each time the
- timer interrupt fires. TimerPeriod defines the minimum
- time between timer interrupts, so TimerPeriod will also
- be the minimum time between calls to the registered
- handler.
-
- @param SetTimerPeriod
- Sets the period of the timer interrupt in 100 nS units.
- This function is optional, and may return EFI_UNSUPPORTED.
- If this function is supported, then the timer period will
- be rounded up to the nearest supported timer period.
-
-
- @param GetTimerPeriod
- Retrieves the period of the timer interrupt in 100 nS units.
-
- @param GenerateSoftInterrupt
- Generates a soft timer interrupt that simulates the firing of
- the timer interrupt. This service can be used to invoke the registered handler if the timer interrupt has been masked for
- a period of time.
-
-**/
-EFI_TIMER_ARCH_PROTOCOL gTimer = {
- TimerDriverRegisterHandler,
- TimerDriverSetTimerPeriod,
- TimerDriverGetTimerPeriod,
- TimerDriverGenerateSoftInterrupt
-};
-
-/**
-
- C Interrupt Handler called in the interrupt context when Source interrupt is active.
-
-
- @param Source Source of the interrupt. Hardware routing off a specific platform defines
- what source means.
-
- @param SystemContext Pointer to system register context. Mostly used by debuggers and will
- update the system context after the return from the interrupt if
- modified. Don't change these values unless you know what you are doing
-
-**/
-VOID
-EFIAPI
-TimerInterruptHandler (
- IN HARDWARE_INTERRUPT_SOURCE Source,
- IN EFI_SYSTEM_CONTEXT SystemContext
- )
-{
- EFI_TPL OriginalTPL;
-
- //
- // DXE core uses this callback for the EFI timer tick. The DXE core uses locks
- // that raise to TPL_HIGH and then restore back to current level. Thus we need
- // to make sure TPL level is set to TPL_HIGH while we are handling the timer tick.
- //
- OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);
-
- // Check if the timer interrupt is active
- if ((ArmArchTimerGetTimerCtrlReg () ) & ARM_ARCH_TIMER_ISTATUS) {
-
- // Signal end of interrupt early to help avoid losing subsequent ticks from long duration handlers
- gInterrupt->EndOfInterrupt (gInterrupt, Source);
-
- if (mTimerNotifyFunction) {
- mTimerNotifyFunction (mTimerPeriod);
- }
-
- // Reload the Timer
- TimerDriverSetTimerPeriod (&gTimer, FixedPcdGet32(PcdTimerPeriod));
- }
-
- // Enable timer interrupts
- gInterrupt->EnableInterruptSource (gInterrupt, Source);
-
- gBS->RestoreTPL (OriginalTPL);
-}
-
-
-/**
- Initialize the state information for the Timer Architectural Protocol and
- the Timer Debug support protocol that allows the debugger to break into a
- running program.
-
- @param ImageHandle of the loaded driver
- @param SystemTable Pointer to the System Table
-
- @retval EFI_SUCCESS Protocol registered
- @retval EFI_OUT_OF_RESOURCES Cannot allocate protocol data structure
- @retval EFI_DEVICE_ERROR Hardware problems
-
-**/
-EFI_STATUS
-EFIAPI
-TimerInitialize (
- IN EFI_HANDLE ImageHandle,
- IN EFI_SYSTEM_TABLE *SystemTable
- )
-{
- EFI_HANDLE Handle = NULL;
- EFI_STATUS Status;
- UINTN TimerCtrlReg;
-
- if (ArmIsArchTimerImplemented () == 0) {
- DEBUG ((EFI_D_ERROR, "ARM Architectural Timer is not available in the CPU, hence cann't use this Driver \n"));
- ASSERT (0);
- }
-
- // Find the interrupt controller protocol. ASSERT if not found.
- Status = gBS->LocateProtocol (&gHardwareInterruptProtocolGuid, NULL, (VOID **)&gInterrupt);
- ASSERT_EFI_ERROR (Status);
-
- // Disable the timer
- Status = TimerDriverSetTimerPeriod (&gTimer, 0);
- ASSERT_EFI_ERROR (Status);
-
- // Install secure and Non-secure interrupt handlers
- // Note: Because it is not possible to determine the security state of the
- // CPU dynamically, we just install interrupt handler for both sec and non-sec
- // timer PPI
- Status = gInterrupt->RegisterInterruptSource (gInterrupt, PcdGet32 (PcdArmArchTimerSecIntrNum), TimerInterruptHandler);
- ASSERT_EFI_ERROR (Status);
-
- Status = gInterrupt->RegisterInterruptSource (gInterrupt, PcdGet32 (PcdArmArchTimerIntrNum), TimerInterruptHandler);
- ASSERT_EFI_ERROR (Status);
-
- // Unmask timer interrupts
- TimerCtrlReg = ArmArchTimerGetTimerCtrlReg ();
- TimerCtrlReg &= ~ARM_ARCH_TIMER_IMASK;
- ArmArchTimerSetTimerCtrlReg (TimerCtrlReg);
-
- // Set up default timer
- Status = TimerDriverSetTimerPeriod (&gTimer, FixedPcdGet32(PcdTimerPeriod)); // TIMER_DEFAULT_PERIOD
- ASSERT_EFI_ERROR (Status);
-
- // Install the Timer Architectural Protocol onto a new handle
- Status = gBS->InstallMultipleProtocolInterfaces(
- &Handle,
- &gEfiTimerArchProtocolGuid, &gTimer,
- NULL
- );
- ASSERT_EFI_ERROR(Status);
-
- // enable Secure timer interrupts
- Status = gInterrupt->EnableInterruptSource (gInterrupt, PcdGet32 (PcdArmArchTimerSecIntrNum));
-
- // enable NonSecure timer interrupts
- Status = gInterrupt->EnableInterruptSource (gInterrupt, PcdGet32 (PcdArmArchTimerIntrNum));
-
- // Register for an ExitBootServicesEvent
- Status = gBS->CreateEvent (EVT_SIGNAL_EXIT_BOOT_SERVICES, TPL_NOTIFY, ExitBootServicesEvent, NULL, &EfiExitBootServicesEvent);
- ASSERT_EFI_ERROR (Status);
-
- return Status;
-}
+/** @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/ArmGenericTimerCounterLib.h>\r
+#include <Library/ArmArchTimer.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
+// The latest Timer Tick calculated for mTimerPeriod\r
+UINT64 mTimerTicks = 0;\r
+// Number of elapsed period since the last Timer interrupt\r
+UINT64 mElapsedPeriod = 1;\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
+ ArmGenericTimerDisableTimer ();\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 CounterValue;\r
+ UINT64 TimerTicks;\r
+ EFI_TPL OriginalTPL;\r
+\r
+ // Always disable the timer\r
+ ArmGenericTimerDisableTimer ();\r
+\r
+ if (TimerPeriod != 0) {\r
+ // mTimerTicks = TimerPeriod in 1ms unit x Frequency.10^-3\r
+ // = TimerPeriod.10^-4 x Frequency.10^-3\r
+ // = (TimerPeriod x Frequency) x 10^-7\r
+ TimerTicks = MultU64x32 (TimerPeriod, FixedPcdGet32 (PcdArmArchTimerFreqInHz));\r
+ TimerTicks = DivU64x32 (TimerTicks, 10000000U);\r
+\r
+ // Raise TPL to update the mTimerTicks and mTimerPeriod to ensure these values\r
+ // are coherent in the interrupt handler\r
+ OriginalTPL = gBS->RaiseTPL (TPL_HIGH_LEVEL);\r
+\r
+ mTimerTicks = TimerTicks;\r
+ mTimerPeriod = TimerPeriod;\r
+ mElapsedPeriod = 1;\r
+\r
+ gBS->RestoreTPL (OriginalTPL);\r
+\r
+ // Get value of the current timer\r
+ CounterValue = ArmGenericTimerGetSystemCount ();\r
+ // Set the interrupt in Current Time + mTimerTick\r
+ ArmGenericTimerSetCompareVal (CounterValue + mTimerTicks);\r
+\r
+ // Enable the timer\r
+ ArmGenericTimerEnableTimer ();\r
+ } else {\r
+ // Save the new timer period\r
+ mTimerPeriod = TimerPeriod;\r
+ // Reset the elapsed period\r
+ mElapsedPeriod = 1;\r
+ }\r
+\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
+ UINT64 CurrentValue;\r
+ UINT64 CompareValue;\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 ((ArmGenericTimerGetTimerCtrlReg () ) & 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 * mElapsedPeriod);\r
+ }\r
+\r
+ //\r
+ // Reload the Timer\r
+ //\r
+\r
+ // Get current counter value\r
+ CurrentValue = ArmGenericTimerGetSystemCount ();\r
+ // Get the counter value to compare with\r
+ CompareValue = ArmGenericTimerGetCompareVal ();\r
+\r
+ // This loop is needed in case we missed interrupts (eg: case when the interrupt handling\r
+ // has taken longer than mTickPeriod).\r
+ // Note: Physical Counter is counting up\r
+ mElapsedPeriod = 0;\r
+ do {\r
+ CompareValue += mTimerTicks;\r
+ mElapsedPeriod++;\r
+ } while (CompareValue < CurrentValue);\r
+\r
+ // Set next compare value\r
+ ArmGenericTimerSetCompareVal (CompareValue);\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 = ArmGenericTimerGetTimerCtrlReg ();\r
+ TimerCtrlReg |= ARM_ARCH_TIMER_IMASK;\r
+ TimerCtrlReg &= ~ARM_ARCH_TIMER_ENABLE;\r
+ ArmGenericTimerSetTimerCtrlReg (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 (PcdArmArchTimerVirtIntrNum), TimerInterruptHandler);\r
+ ASSERT_EFI_ERROR (Status);\r
+\r
+ Status = gInterrupt->RegisterInterruptSource (gInterrupt, PcdGet32 (PcdArmArchTimerHypIntrNum), TimerInterruptHandler);\r
+ ASSERT_EFI_ERROR (Status);\r
+\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
+ ArmGenericTimerSetTimerCtrlReg (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