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Disabled BD_PROCHOT for all CPUs #18

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Disabled BD_PROCHOT for all CPUs #18

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6 changes: 4 additions & 2 deletions TurboMac/TurboMac.cpp
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Original file line number Diff line number Diff line change
Expand Up @@ -18,6 +18,7 @@ const uint32_t IA32_HWP_CAPABILITIES = 0x771;
const uint32_t IA32_HWP_REQUEST = 0x774;
const uint32_t BASE_HWP_VALUE = 0x80000000;
const uint32_t IA32_MISC_ENABLE = 0x1A0;
const uint32_t BD_PROCHOT_REGISTER = 0x1FC;
const uint64_t SPEEDSTEP_ENABLE_BIT = 1 << 16;

const uint32_t FIRST_BYTE_MASK = (1 << 8) - 1;
Expand Down Expand Up @@ -55,8 +56,6 @@ bool TurboMac::start(IOService *provider)

IOLog("Writing to IA32_HWP_REQUEST to request performance between HighestPerformance and GuaranteedPerformance...");
wrmsr64(IA32_HWP_REQUEST, BASE_HWP_VALUE | (highestPerformance << 8) | guaranteedPerformance);

wrmsr64(0x1FC, rdmsr64(0x1FC) ^ 1);
}
else {
IOLog("CPU does not support SpeedShift.");
Expand All @@ -65,6 +64,9 @@ bool TurboMac::start(IOService *provider)
uint64_t enabledFeatures = rdmsr64(IA32_MISC_ENABLE);
wrmsr64(IA32_MISC_ENABLE, enabledFeatures ^ SPEEDSTEP_ENABLE_BIT);
}

IOLog("Disabling BD_PROCHOT...");
wrmsr64(BD_PROCHOT_REGISTER, rdmsr64(BD_PROCHOT_REGISTER) ^ 1);

IOLog("TurboMac fully initialized.");
return res;
Expand Down