Specifications

System BIOS

BIOS event and error reporting

TheBIOSsendstheseeventstotheIPMCduringBIOSstart‐up,earlyPOSTtasks,and

execution:

•Systemevents

• Bootevents

•POSTerroreventsduringearlyPOSTtasks

TheIPMClogstheeventstoitslocalSELandforwardsthemtothe systemSEL.

Correctable and uncorrectable memory error logging

TheIntegratedMemoryController(IMC)supportsECCtodetectandcorrectmemor y

errorswheneverpossible.TheBIOSSMIroutinereportsamemoryerrorsplatformevent

messagetotheIPMCifamemoryerrorisdetected.

ECCandmemoryerrorloggingareenabledfromtheBIOSsetupmenu.TheBIOSinitializes

thesystemaccordingtothesettings.

Correctable memory error logging

EachDIMMintheIMChasahardwarecorrectableECCerrorcounterthatisinitializedto0

atresetandincrementswheneveracorrectablememoryerrorisdetecte d.Whenthe

errorcounterforanysingleDIMMreachesadefinedthreshold(overflow),ainternalSMI

signalsandtheBIOSSMIhandleristriggeredtoreportaplatformeventmessagewith

sensortype0Ch(Memory).

WhentheECCcounterreachesthe limitof10errorswithinanhour,theBIOSsendsa

platformeventmessagewithsensortype0Ch(Memory)withoffset05h(Correctable

ECC/othercorrectablememoryerrorlogginglimitreached)andstopsreporting

correctablememoryerrormessages.Errorcorrectionremainsenabled,butcallstothe

errorhandleraredisabled.

ThefollowingstepsdescribetheprocesstheCPMfollowsforperformingcorrectableerror

loggingifamemoryerroroccurs:

1. Ahardware‐maintainedperDIMMerrorcounterincrementswhenanerroris

detectedonaDIMM.ThehardwarecounterissetintheBIOSbyselectingCorr.Error

Threshold

fromRuntimeErrorLoggingintheAdvancedmenu.

2. Ifthecounteroverflows(comparedtotheCorr.ErrorThresholdBIOSsetting),a

SystemManagementInterrupt(SMI)issignaledandtheBIOSservicestheerror.

3. WhenaSMIoccurs,theBIOSidentifiesthecauseoftheSMIanddeterminesitis

triggeredbyamemoryerror.

4. TheBIOSservicestheerror.