// Cached interrupt vector
volatile UINTN gVector;
+
+/**\r
+ C Interrupt Handler calledin the interrupt context when Source interrupt is active.\r
+\r
+ @param Source Source of the interrupt. Hardware routing off a specific platform defines\r
+ what source means.\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
+**/
VOID
EFIAPI
TimerInterruptHandler (
IN EFI_SYSTEM_CONTEXT SystemContext
)
{
+ 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
+
if (mTimerPeriodicCallback) {
mTimerPeriodicCallback(SystemContext);
}
// Poll interrupt status bits to ensure clearing
while ((MmioRead32(TISR) & TISR_ALL_INTERRUPT_MASK) != TISR_NO_INTERRUPTS_PENDING);
+
+ gBS->RestoreTPL (OriginalTPL);
}
+/**\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
+\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
EFIAPI
TimerDriverRegisterHandler (
return EFI_SUCCESS;
}
+/**\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
+ @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
+**/
EFI_STATUS
EFIAPI
TimerDriverSetTimerPeriod (
return Status;
}
+
+/**\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
+ @retval EFI_SUCCESS The timer period was returned in TimerPeriod.\r
+ @retval EFI_INVALID_PARAMETER TimerPeriod is NULL.\r
+\r
+**/
EFI_STATUS
EFIAPI
TimerDriverGetTimerPeriod (
return EFI_SUCCESS;
}
+/**\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
+**/
EFI_STATUS
EFIAPI
TimerDriverGenerateSoftInterrupt (
return EFI_UNSUPPORTED;
}
+
EFI_STATUS
EFIAPI
TimerDriverRegisterPeriodicCallback (
return EFI_SUCCESS;
}
+
+/**\r
+ Interface stucture for the Timer Architectural Protocol.\r
+\r
+ @par Protocol Description:\r
+ This protocol provides the services to initialize a periodic timer \r
+ interrupt, and to register a handler that is called each time the timer\r
+ interrupt fires. It may also provide a service to adjust the rate of the\r
+ periodic timer interrupt. When a timer interrupt occurs, the handler is \r
+ passed the amount of time that has passed since the previous timer \r
+ interrupt.\r
+\r
+ @param RegisterHandler\r
+ Registers a handler that will be called each time the \r
+ timer interrupt fires. TimerPeriod defines the minimum \r
+ time between timer interrupts, so TimerPeriod will also \r
+ be the minimum time between calls to the registered \r
+ handler.\r
+\r
+ @param SetTimerPeriod\r
+ Sets the period of the timer interrupt in 100 nS units. \r
+ This function is optional, and may return EFI_UNSUPPORTED. \r
+ If this function is supported, then the timer period will \r
+ be rounded up to the nearest supported timer period.\r
+\r
+ @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 \r
+ registered handler if the timer interrupt has been masked for \r
+ a period of time.\r
+\r
+**/
EFI_TIMER_ARCH_PROTOCOL gTimer = {
TimerDriverRegisterHandler,
TimerDriverSetTimerPeriod,
TimerDriverRegisterPeriodicCallback
};
+
+/**\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
+**/
EFI_STATUS
EFIAPI
TimerInitialize (