diff --git a/UefiCpuPkg/Library/RegisterCpuFeaturesLib/CpuFeaturesInitialize.c b/UefiCpuPkg/Library/RegisterCpuFeaturesLib/CpuFeaturesInitialize.c index aff7ad600c..1746f4f07f 100644 --- a/UefiCpuPkg/Library/RegisterCpuFeaturesLib/CpuFeaturesInitialize.c +++ b/UefiCpuPkg/Library/RegisterCpuFeaturesLib/CpuFeaturesInitialize.c @@ -1071,10 +1071,12 @@ CpuFeaturesDetect ( CpuInitDataInitialize (); - // - // Wakeup all APs for data collection. - // - StartupAPsWorker (CollectProcessorData, NULL); + if (CpuFeaturesData->NumberOfCpus > 1) { + // + // Wakeup all APs for data collection. + // + StartupAPsWorker (CollectProcessorData, NULL); + } // // Collect data on BSP diff --git a/UefiCpuPkg/Library/RegisterCpuFeaturesLib/DxeRegisterCpuFeaturesLib.c b/UefiCpuPkg/Library/RegisterCpuFeaturesLib/DxeRegisterCpuFeaturesLib.c index 9c78a2d993..ffd99046a6 100644 --- a/UefiCpuPkg/Library/RegisterCpuFeaturesLib/DxeRegisterCpuFeaturesLib.c +++ b/UefiCpuPkg/Library/RegisterCpuFeaturesLib/DxeRegisterCpuFeaturesLib.c @@ -229,31 +229,36 @@ CpuFeaturesInitialize ( OldBspNumber = GetProcessorIndex (CpuFeaturesData); CpuFeaturesData->BspNumber = OldBspNumber; - Status = gBS->CreateEvent ( - EVT_NOTIFY_WAIT, - TPL_CALLBACK, - EfiEventEmptyFunction, - NULL, - &MpEvent - ); - ASSERT_EFI_ERROR (Status); + if (CpuFeaturesData->NumberOfCpus > 1) { + Status = gBS->CreateEvent ( + EVT_NOTIFY_WAIT, + TPL_CALLBACK, + EfiEventEmptyFunction, + NULL, + &MpEvent + ); + ASSERT_EFI_ERROR (Status); + + // + // Wakeup all APs for programming. + // + StartupAPsWorker (SetProcessorRegister, MpEvent); + } - // - // Wakeup all APs for programming. - // - StartupAPsWorker (SetProcessorRegister, MpEvent); // // Programming BSP // SetProcessorRegister (CpuFeaturesData); - // - // Wait all processors to finish the task. - // - do { - Status = gBS->CheckEvent (MpEvent); - } while (Status == EFI_NOT_READY); - ASSERT_EFI_ERROR (Status); + if (CpuFeaturesData->NumberOfCpus > 1) { + // + // Wait all processors to finish the task. + // + do { + Status = gBS->CheckEvent (MpEvent); + } while (Status == EFI_NOT_READY); + ASSERT_EFI_ERROR (Status); + } // // Switch to new BSP if required diff --git a/UefiCpuPkg/Library/RegisterCpuFeaturesLib/PeiRegisterCpuFeaturesLib.c b/UefiCpuPkg/Library/RegisterCpuFeaturesLib/PeiRegisterCpuFeaturesLib.c index 2b1553f9b8..8ad5a40e5a 100644 --- a/UefiCpuPkg/Library/RegisterCpuFeaturesLib/PeiRegisterCpuFeaturesLib.c +++ b/UefiCpuPkg/Library/RegisterCpuFeaturesLib/PeiRegisterCpuFeaturesLib.c @@ -273,10 +273,13 @@ CpuFeaturesInitialize ( // DXE type instance. // - // - // Wakeup all APs for programming. - // - StartupAPsWorker (SetProcessorRegister, NULL); + if (CpuFeaturesData->NumberOfCpus > 1) { + // + // Wakeup all APs for programming. + // + StartupAPsWorker (SetProcessorRegister, NULL); + } + // // Programming BSP //