X-Git-Url: https://git.proxmox.com/?p=mirror_edk2.git;a=blobdiff_plain;f=ArmPkg%2FDrivers%2FTimerDxe%2FTimerDxe.c;h=cbc34e8e412123515087f7e3e0080fbb93d84b44;hp=50de7668eaa08b11dd6ab50ce843135a60b52c55;hb=1e57a46299244793beb27e74be171d1540606999;hpb=5767f22fca7c337cdc113e14b411c1fd0ea7bd53 diff --git a/ArmPkg/Drivers/TimerDxe/TimerDxe.c b/ArmPkg/Drivers/TimerDxe/TimerDxe.c index 50de7668ea..cbc34e8e41 100644 --- a/ArmPkg/Drivers/TimerDxe/TimerDxe.c +++ b/ArmPkg/Drivers/TimerDxe/TimerDxe.c @@ -1,380 +1,380 @@ -/** @file - Timer Architecture Protocol driver of the ARM flavor - - Copyright (c) 2011 ARM Ltd. All rights reserved.
- - 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 - -#include -#include -#include -#include -#include -#include -#include -#include -#include - -#include -#include - -// 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 + Timer Architecture Protocol driver of the ARM flavor + + Copyright (c) 2011 ARM Ltd. All rights reserved.
+ + 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 + +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include + +// 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; +}