X-Git-Url: https://git.proxmox.com/?a=blobdiff_plain;f=Omap35xxPkg%2FTimerDxe%2FTimer.c;h=8b56d457e4131ddedf08844f7388d69446c3cf72;hb=f33d5d68abc02727dc828c1079e72ab65e1d63af;hp=2753b98d1a61f5b67af87c7afdb87d9df686c7ab;hpb=026e30c4bb80a73ac7c5c286711ae07b1c51108b;p=mirror_edk2.git diff --git a/Omap35xxPkg/TimerDxe/Timer.c b/Omap35xxPkg/TimerDxe/Timer.c index 2753b98d1a..8b56d457e4 100644 --- a/Omap35xxPkg/TimerDxe/Timer.c +++ b/Omap35xxPkg/TimerDxe/Timer.c @@ -1,539 +1,376 @@ -/** @file - Template for Timer Architecture Protocol driver of the ARM flavor - - Copyright (c) 2008-2009, Apple Inc. All rights reserved. - - 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 - -#include - - -// The notification function to call on every timer interrupt. -volatile EFI_TIMER_NOTIFY mTimerNotifyFunction = (EFI_TIMER_NOTIFY)NULL; -volatile EFI_PERIODIC_CALLBACK mTimerPeriodicCallback = (EFI_PERIODIC_CALLBACK)NULL; - - -// The current period of the timer interrupt -volatile UINT64 mTimerPeriod = 0; - -// Cached copy of the Hardware Interrupt protocol instance -EFI_HARDWARE_INTERRUPT_PROTOCOL *gInterrupt = NULL; - -// Cached registers -volatile UINT32 TISR; -volatile UINT32 TCLR; -volatile UINT32 TLDR; -volatile UINT32 TCRR; -volatile UINT32 TIER; - -// Cached interrupt vector -volatile UINTN gVector; - - -/** - - C Interrupt Handler calledin 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); - - - if (mTimerPeriodicCallback) { - mTimerPeriodicCallback(SystemContext); - } - - if (mTimerNotifyFunction) { - mTimerNotifyFunction(mTimerPeriod); - } - - // Clear all timer interrupts - MmioWrite32 (TISR, TISR_CLEAR_ALL); - - // Poll interrupt status bits to ensure clearing - while ((MmioRead32(TISR) & TISR_ALL_INTERRUPT_MASK) != TISR_NO_INTERRUPTS_PENDING); - - gBS->RestoreTPL (OriginalTPL); -} - -/** - - 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; -} - -/** - - 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 - ) -{ - EFI_STATUS Status; - UINT64 TimerCount; - INT32 LoadValue; - - if (TimerPeriod == 0) { - // Turn off GPTIMER3 - MmioWrite32 (TCLR, TCLR_ST_OFF); - - Status = gInterrupt->DisableInterruptSource(gInterrupt, gVector); - } else { - // Calculate required timer count - TimerCount = DivU64x32(TimerPeriod * 100, PcdGet32(PcdEmbeddedFdPerformanceCounterPeriodInNanoseconds)); - - // Set GPTIMER3 Load register - LoadValue = (INT32) -TimerCount; - MmioWrite32 (TLDR, LoadValue); - MmioWrite32 (TCRR, LoadValue); - - // Enable Overflow interrupt - MmioWrite32 (TIER, TIER_TCAR_IT_DISABLE | TIER_OVF_IT_ENABLE | TIER_MAT_IT_DISABLE); - - // Turn on GPTIMER3, it will reload at overflow - MmioWrite32 (TCLR, TCLR_AR_AUTORELOAD | TCLR_ST_ON); - - Status = gInterrupt->EnableInterruptSource(gInterrupt, gVector); - } - - // - // Save the new timer period - // - mTimerPeriod = TimerPeriod; - return Status; -} - - -/** - - 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; -} - - -EFI_STATUS -EFIAPI -TimerDriverRegisterPeriodicCallback ( - IN TIMER_DEBUG_SUPPORT_PROTOCOL *This, - IN EFI_PERIODIC_CALLBACK PeriodicCallback - ) -{ - if ((PeriodicCallback == NULL) && (mTimerPeriodicCallback == NULL)) { - return EFI_INVALID_PARAMETER; - } - - if ((PeriodicCallback != NULL) && (mTimerPeriodicCallback != NULL)) { - return EFI_ALREADY_STARTED; - } - - mTimerPeriodicCallback = PeriodicCallback; - - return EFI_SUCCESS; -} - - -/** - - Interface stucture 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 -}; - -TIMER_DEBUG_SUPPORT_PROTOCOL gTimerDebugSupport = { - TimerDriverRegisterPeriodicCallback -}; - - -/** - - 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; - UINT32 TimerBaseAddress; - - // Find the interrupt controller protocol. ASSERT if not found. - Status = gBS->LocateProtocol(&gHardwareInterruptProtocolGuid, NULL, (VOID **)&gInterrupt); - ASSERT_EFI_ERROR (Status); - - // Set up the timer registers - TimerBaseAddress = TimerBase(FixedPcdGet32(PcdBeagleArchTimer)); - TISR = TimerBaseAddress + GPTIMER_TISR; - TCLR = TimerBaseAddress + GPTIMER_TCLR; - TLDR = TimerBaseAddress + GPTIMER_TLDR; - TCRR = TimerBaseAddress + GPTIMER_TCRR; - TIER = TimerBaseAddress + GPTIMER_TIER; - - // Disable the timer - Status = TimerDriverSetTimerPeriod(&gTimer, 0); - ASSERT_EFI_ERROR (Status); - - // Install interrupt handler - gVector = InterruptVectorForTimer(FixedPcdGet32(PcdBeagleArchTimer)); - Status = gInterrupt->RegisterInterruptSource(gInterrupt, gVector, TimerInterruptHandler); - ASSERT_EFI_ERROR (Status); - - // Set up default timer - Status = TimerDriverSetTimerPeriod(&gTimer, FixedPcdGet32(PcdTimerPeriod)); - ASSERT_EFI_ERROR (Status); - - // Install the Timer Architectural Protocol onto a new handle - Status = gBS->InstallMultipleProtocolInterfaces(&Handle, - &gEfiTimerArchProtocolGuid, &gTimer, - &gTimerDebugSupportProtocolGuid, &gTimerDebugSupport, - NULL); - ASSERT_EFI_ERROR(Status); - - return Status; -} - +/** @file + Template for Timer Architecture Protocol driver of the ARM flavor + + Copyright (c) 2008 - 2009, Apple Inc. 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. +volatile EFI_TIMER_NOTIFY mTimerNotifyFunction = (EFI_TIMER_NOTIFY)NULL; + + +// The current period of the timer interrupt +volatile UINT64 mTimerPeriod = 0; + +// Cached copy of the Hardware Interrupt protocol instance +EFI_HARDWARE_INTERRUPT_PROTOCOL *gInterrupt = NULL; + +// Cached registers +volatile UINT32 TISR; +volatile UINT32 TCLR; +volatile UINT32 TLDR; +volatile UINT32 TCRR; +volatile UINT32 TIER; + +// Cached interrupt vector +volatile UINTN gVector; + + +/** + + C Interrupt Handler calledin 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); + + if (mTimerNotifyFunction) { + mTimerNotifyFunction(mTimerPeriod); + } + + // Clear all timer interrupts + MmioWrite32 (TISR, TISR_CLEAR_ALL); + + // Poll interrupt status bits to ensure clearing + while ((MmioRead32 (TISR) & TISR_ALL_INTERRUPT_MASK) != TISR_NO_INTERRUPTS_PENDING); + + gBS->RestoreTPL (OriginalTPL); +} + +/** + 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; +} + +/** + + 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 + ) +{ + EFI_STATUS Status; + UINT64 TimerCount; + INT32 LoadValue; + + if (TimerPeriod == 0) { + // Turn off GPTIMER3 + MmioWrite32 (TCLR, TCLR_ST_OFF); + + Status = gInterrupt->DisableInterruptSource(gInterrupt, gVector); + } else { + // Calculate required timer count + TimerCount = DivU64x32(TimerPeriod * 100, PcdGet32(PcdEmbeddedPerformanceCounterPeriodInNanoseconds)); + + // Set GPTIMER3 Load register + LoadValue = (INT32) -TimerCount; + MmioWrite32 (TLDR, LoadValue); + MmioWrite32 (TCRR, LoadValue); + + // Enable Overflow interrupt + MmioWrite32 (TIER, TIER_TCAR_IT_DISABLE | TIER_OVF_IT_ENABLE | TIER_MAT_IT_DISABLE); + + // Turn on GPTIMER3, it will reload at overflow + MmioWrite32 (TCLR, TCLR_AR_AUTORELOAD | TCLR_ST_ON); + + Status = gInterrupt->EnableInterruptSource(gInterrupt, gVector); + } + + // + // Save the new timer period + // + mTimerPeriod = TimerPeriod; + return Status; +} + + +/** + 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 stucture 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 +}; + + +/** + 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; + UINT32 TimerBaseAddress; + + // Find the interrupt controller protocol. ASSERT if not found. + Status = gBS->LocateProtocol (&gHardwareInterruptProtocolGuid, NULL, (VOID **)&gInterrupt); + ASSERT_EFI_ERROR (Status); + + // Set up the timer registers + TimerBaseAddress = TimerBase (FixedPcdGet32(PcdOmap35xxArchTimer)); + TISR = TimerBaseAddress + GPTIMER_TISR; + TCLR = TimerBaseAddress + GPTIMER_TCLR; + TLDR = TimerBaseAddress + GPTIMER_TLDR; + TCRR = TimerBaseAddress + GPTIMER_TCRR; + TIER = TimerBaseAddress + GPTIMER_TIER; + + // Disable the timer + Status = TimerDriverSetTimerPeriod (&gTimer, 0); + ASSERT_EFI_ERROR (Status); + + // Install interrupt handler + gVector = InterruptVectorForTimer (FixedPcdGet32(PcdOmap35xxArchTimer)); + Status = gInterrupt->RegisterInterruptSource (gInterrupt, gVector, TimerInterruptHandler); + ASSERT_EFI_ERROR (Status); + + // Turn on the functional clock for Timer + MmioOr32 (CM_FCLKEN_PER, CM_FCLKEN_PER_EN_GPT3_ENABLE); + + // Set up default timer + Status = TimerDriverSetTimerPeriod (&gTimer, FixedPcdGet32(PcdTimerPeriod)); + ASSERT_EFI_ERROR (Status); + + // Install the Timer Architectural Protocol onto a new handle + Status = gBS->InstallMultipleProtocolInterfaces ( + &Handle, + &gEfiTimerArchProtocolGuid, &gTimer, + NULL + ); + ASSERT_EFI_ERROR(Status); + + return Status; +} +