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Fix APU timer ticking at wrong frequency

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Silent 2020-10-24 13:09:37 +02:00
parent 724a1ca684
commit 0f88b77bfe
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1 changed files with 29 additions and 13 deletions
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42
src/core/hle/DSOUND/DirectSound/DirectSound.cpp
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@ -51,27 +51,43 @@
// Temporary APU Timer Functions
// TODO: Move these to LLE APUDevice once we have one!
#define APU_TIMER_FREQUENCY 48000
LARGE_INTEGER APUInitialPerformanceCounter;
double NativeToXboxAPU_FactorForPerformanceFrequency = 0;
static constexpr uint32_t APU_TIMER_FREQUENCY = 48000;
static constexpr uint32_t SEC_TO_NSEC = 1000000000; // For seconds -> nanoseconds conversions
static uint64_t NativeToXbox_FactorForApu = 0;
static LARGE_INTEGER LastApuQPC;
static DWORD CurrentApu = 0;
static ULONGLONG CurrentApuRemainder = 0; // Must be 64-bit because it stores a nanosecond precision remainder
void ResetApuTimer()
{
// Measure current host performance counter and frequency
QueryPerformanceCounter(&APUInitialPerformanceCounter);
NativeToXboxAPU_FactorForPerformanceFrequency = (double)APU_TIMER_FREQUENCY / APUInitialPerformanceCounter.QuadPart;
// Measure current host performance counter and frequency
LARGE_INTEGER HostClockFrequency;
QueryPerformanceFrequency(&HostClockFrequency);
NativeToXbox_FactorForApu = Muldiv64(HostClockFrequency.QuadPart, SEC_TO_NSEC, APU_TIMER_FREQUENCY);
LARGE_INTEGER tsc;
QueryPerformanceCounter(&tsc);
LastApuQPC = tsc;
CurrentApu = 0;
CurrentApuRemainder = 0;
}
uint32_t GetAPUTime()
{
::LARGE_INTEGER PerformanceCounter;
QueryPerformanceCounter(&PerformanceCounter);
LARGE_INTEGER tsc;
QueryPerformanceCounter(&tsc);
// Re-Base on the time DirectSoundCreate was called
PerformanceCounter.QuadPart -= APUInitialPerformanceCounter.QuadPart;
// Apply a delta to make it appear to tick at 48khz
PerformanceCounter.QuadPart = (ULONGLONG)(NativeToXboxAPU_FactorForPerformanceFrequency * PerformanceCounter.QuadPart);
return (DWORD)PerformanceCounter.QuadPart;
LARGE_INTEGER lastTsc = std::exchange(LastApuQPC, tsc);
tsc.QuadPart -= lastTsc.QuadPart;
tsc.QuadPart *= SEC_TO_NSEC;
tsc.QuadPart += CurrentApuRemainder;
DWORD quotient = static_cast<DWORD>(tsc.QuadPart / NativeToXbox_FactorForApu);
ULONGLONG remainder = tsc.QuadPart % NativeToXbox_FactorForApu;
CurrentApuRemainder = remainder;
return CurrentApu += quotient;
}