internal static void ApicTimer(PMTimer pmTimer, ApicTimer apicTimer)
{
apicTimer.SetDivisor(1);
apicTimer.SetOneShot();
apicTimer.SetInterruptEnabled(false);
apicTimer.SetInitialCount(~0u);
uint apicLast = apicTimer.Value;
uint pmLast = pmTimer.Value;
uint pmLimit = PMTimer.FrequencyHz / 15;
uint pmAccum = 0;
uint apicNow = 0;
// Initial measurements
apicLast = apicTimer.Value;
pmLast = pmTimer.Value;
do
{
apicNow = apicTimer.Value;
uint pmNow = pmTimer.Value | 0xff000000;
pmAccum += PmDelta(pmNow, pmLast);
pmLast = pmNow;
} while (pmAccum < pmLimit);
ulong apicHz = PMTimer.FrequencyHz * (ulong)(apicLast - apicNow) / pmAccum;
DebugStub.Print("Cpu{0}: APIC timer frequency {1} Hz\n",
__arglist(Processor.CurrentProcessor.Id, apicHz));
apicTimer.SetBusFrequency((uint)apicHz);
}
