/**
Enable/Disable the interrupt of debug timer and return the interrupt state
prior to the operation.
If EnableStatus is TRUE, enable the interrupt of debug timer.
If EnableStatus is FALSE, disable the interrupt of debug timer.
@param[in] EnableStatus Enable/Disable.
@retval TRUE Debug timer interrupt were enabled on entry to this call.
@retval FALSE Debug timer interrupt were disabled on entry to this call.
**/
BOOLEAN
EFIAPI
SaveAndSetDebugTimerInterrupt (
IN BOOLEAN EnableStatus
)
{
BOOLEAN OldDebugTimerInterruptState;
OldDebugTimerInterruptState = GetApicTimerInterruptState ();
if (OldDebugTimerInterruptState != EnableStatus) {
if (EnableStatus) {
EnableApicTimerInterrupt ();
} else {
DisableApicTimerInterrupt ();
}
//
// Validate the Debug Timer interrupt state
// This will make additional delay after Local Apic Timer interrupt state is changed.
// Thus, CPU could handle the potential pending interrupt of Local Apic timer.
//
while (GetApicTimerInterruptState () != EnableStatus) {
CpuPause ();
}
}
return OldDebugTimerInterruptState;
}
/**
Initialize CPU local APIC timer.
@param[out] TimerFrequency Local APIC timer frequency returned.
@param[in] DumpFlag If TRUE, dump Local APIC timer's parameter.
@return 32-bit Local APIC timer init count.
**/
UINT32
InitializeDebugTimer (
OUT UINT32 *TimerFrequency,
IN BOOLEAN DumpFlag
)
{
UINTN ApicTimerDivisor;
UINT32 InitialCount;
UINT32 ApicTimerFrequency;
InitializeLocalApicSoftwareEnable (TRUE);
GetApicTimerState (&ApicTimerDivisor, NULL, NULL);
ApicTimerFrequency = PcdGet32(PcdFSBClock) / (UINT32)ApicTimerDivisor;
//
// Cpu Local Apic timer interrupt frequency, it is set to 0.1s
//
InitialCount = (UINT32)DivU64x32 (
MultU64x64 (
ApicTimerFrequency,
DEBUG_TIMER_INTERVAL
),
1000000u
);
InitializeApicTimer (ApicTimerDivisor, InitialCount, TRUE, DEBUG_TIMER_VECTOR);
//
// Disable Debug Timer interrupt to avoid it is delivered before Debug Port
// is initialized
//
DisableApicTimerInterrupt ();
if (DumpFlag) {
DEBUG ((EFI_D_INFO, "Debug Timer: FSB Clock = %d\n", PcdGet32(PcdFSBClock)));
DEBUG ((EFI_D_INFO, "Debug Timer: Divisor = %d\n", ApicTimerDivisor));
DEBUG ((EFI_D_INFO, "Debug Timer: Frequency = %d\n", ApicTimerFrequency));
DEBUG ((EFI_D_INFO, "Debug Timer: InitialCount = %d\n", InitialCount));
}
if (TimerFrequency != NULL) {
*TimerFrequency = ApicTimerFrequency;
}
return InitialCount;
}
/**
Enable/Disable the interrupt of debug timer and return the interrupt state
prior to the operation.
If EnableStatus is TRUE, enable the interrupt of debug timer.
If EnableStatus is FALSE, disable the interrupt of debug timer.
@param[in] EnableStatus Enable/Disable.
@retval TRUE Debug timer interrupt were enabled on entry to this call.
@retval FALSE Debug timer interrupt were disabled on entry to this call.
**/
BOOLEAN
EFIAPI
SaveAndSetDebugTimerInterrupt (
IN BOOLEAN EnableStatus
)
{
BOOLEAN OldInterruptState;
BOOLEAN OldDebugTimerInterruptState;
OldInterruptState = SaveAndDisableInterrupts ();
OldDebugTimerInterruptState = GetApicTimerInterruptState ();
if (EnableStatus) {
EnableApicTimerInterrupt ();
} else {
DisableApicTimerInterrupt ();
}
SetInterruptState (OldInterruptState);
return OldDebugTimerInterruptState;
}
