mirror of https://github.com/acidanthera/audk.git
fe0c2770a7
BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=1810 This patch covers two problems. 1. Current code gets CPUID_THERMAL_POWER_MANAGEMENT in ClockModulationInitialize() and uses its ECMD bit for all processors. But ClockModulationInitialize() is only executed by BSP, that means the bit is just for BSP. It may have no functionality issue as all processors may have same bit value in a great possibility. But for good practice, the code should get CPUID_THERMAL_POWER_MANAGEMENT in ClockModulationSupport (executed by all processors), and then use them in ClockModulationInitialize() for all processors. We can see that Aesni.c (and others) have used this good practice. 2. Current code uses 3 CPU_REGISTER_TABLE_WRITE_FIELD for MSR_IA32_CLOCK_MODULATION in ClockModulationInitialize(), they can be reduced to 1 CPU_REGISTER_TABLE_WRITE64 by getting MSR_IA32_CLOCK_MODULATION for all processors in ClockModulationSupport() and then update fields for register table write in ClockModulationInitialize(). We may argue that there may be more times of MSR_IA32_CLOCK_MODULATION getting. But actually the times of MSR_IA32_CLOCK_MODULATION getting could be also reduced. The reason is in ProgramProcessorRegister() of CpuFeaturesInitialize.c, AsmMsrBitFieldWrite64 (AsmReadMsr64 + AsmWriteMsr64) will be used for CPU_REGISTER_TABLE_WRITE_FIELD, and AsmWriteMsr64 will be used for CPU_REGISTER_TABLE_WRITE64. The times of MSR accessing could be reduced with this patch. Without the patch: 3 CPU_REGISTER_TABLE_WRITE_FIELD (in ClockModulationInitialize) ==> 3 AsmMsrBitFieldWrite64 ==> 3 AsmReadMsr64 + 3 AsmWriteMsr64 With the patch: 1 AsmReadMsr64 (in ClockModulationSupport) + 1 CPU_REGISTER_TABLE_WRITE64 (in ClockModulationInitialize) ==> 1 AsmWriteMsr64 Cc: Laszlo Ersek <lersek@redhat.com> Cc: Eric Dong <eric.dong@intel.com> Cc: Ray Ni <ray.ni@intel.com> Cc: Chandana Kumar <chandana.c.kumar@intel.com> Cc: Kevin Li <kevin.y.li@intel.com> Signed-off-by: Star Zeng <star.zeng@intel.com> Reviewed-by: Ray Ni <ray.ni@intel.com> |
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| .. | ||
| Aesni.c | ||
| C1e.c | ||
| ClockModulation.c | ||
| CpuCommonFeatures.h | ||
| CpuCommonFeaturesLib.c | ||
| CpuCommonFeaturesLib.inf | ||
| CpuCommonFeaturesLib.uni | ||
| Eist.c | ||
| ExecuteDisable.c | ||
| FastStrings.c | ||
| FeatureControl.c | ||
| LimitCpuIdMaxval.c | ||
| MachineCheck.c | ||
| MonitorMwait.c | ||
| PendingBreak.c | ||
| Ppin.c | ||
| ProcTrace.c | ||
| X2Apic.c | ||