检查ibis模型的时候，出现如下警告，怎么处理？

WARNING - Model CLKIN_800 Receiver Thresholds: Vcross_low must be specified for differential receivers (Pin 30)
WARNING - Model CLKIN_800 Receiver Thresholds: Vcross_high must be specified for differential receivers (Pin 30)
WARNING - Model CLKIN_800 Receiver Thresholds: Vdiff_ac must be specified for differential receivers (Pin 30)
WARNING - Model CLKIN_800 Receiver Thresholds: Vdiff_dc must be specified for differential receivers (Pin 30)
WARNING - Model CLKIN_800 Receiver Thresholds: Tdiffslew_ac must be specified for differential receivers (Pin 30)
WARNING - Model DQ_HALF_ODT150_800 Receiver Thresholds: Vcross_low must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT150_800 Receiver Thresholds: Vcross_high must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT150_800 Receiver Thresholds: Vdiff_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT150_800 Receiver Thresholds: Vdiff_dc must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT150_800 Receiver Thresholds: Tdiffslew_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT75_800 Receiver Thresholds: Vcross_low must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT75_800 Receiver Thresholds: Vcross_high must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT75_800 Receiver Thresholds: Vdiff_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT75_800 Receiver Thresholds: Vdiff_dc must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT75_800 Receiver Thresholds: Tdiffslew_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT50_800 Receiver Thresholds: Vcross_low must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT50_800 Receiver Thresholds: Vcross_high must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT50_800 Receiver Thresholds: Vdiff_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT50_800 Receiver Thresholds: Vdiff_dc must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT50_800 Receiver Thresholds: Tdiffslew_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_800 Receiver Thresholds: Vcross_low must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_800 Receiver Thresholds: Vcross_high must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_800 Receiver Thresholds: Vdiff_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_800 Receiver Thresholds: Vdiff_dc must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_800 Receiver Thresholds: Tdiffslew_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT150_800 Receiver Thresholds: Vcross_low must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT150_800 Receiver Thresholds: Vcross_high must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT150_800 Receiver Thresholds: Vdiff_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT150_800 Receiver Thresholds: Vdiff_dc must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT150_800 Receiver Thresholds: Tdiffslew_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT75_800 Receiver Thresholds: Vcross_low must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT75_800 Receiver Thresholds: Vcross_high must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT75_800 Receiver Thresholds: Vdiff_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT75_800 Receiver Thresholds: Vdiff_dc must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT75_800 Receiver Thresholds: Tdiffslew_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT50_800 Receiver Thresholds: Vcross_low must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT50_800 Receiver Thresholds: Vcross_high must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT50_800 Receiver Thresholds: Vdiff_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT50_800 Receiver Thresholds: Vdiff_dc must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT50_800 Receiver Thresholds: Tdiffslew_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_800 Receiver Thresholds: Vcross_low must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_800 Receiver Thresholds: Vcross_high must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_800 Receiver Thresholds: Vdiff_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_800 Receiver Thresholds: Vdiff_dc must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_800 Receiver Thresholds: Tdiffslew_ac must be specified for differential receivers (Pin 53)
WARNING - Model CLKIN_533 Receiver Thresholds: Vcross_low must be specified for differential receivers (Pin 30)
WARNING - Model CLKIN_533 Receiver Thresholds: Vcross_high must be specified for differential receivers (Pin 30)
WARNING - Model CLKIN_533 Receiver Thresholds: Vdiff_ac must be specified for differential receivers (Pin 30)
WARNING - Model CLKIN_533 Receiver Thresholds: Vdiff_dc must be specified for differential receivers (Pin 30)
WARNING - Model CLKIN_533 Receiver Thresholds: Tdiffslew_ac must be specified for differential receivers (Pin 30)
WARNING - Model DQ_HALF_ODT150_533 Receiver Thresholds: Vcross_low must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT150_533 Receiver Thresholds: Vcross_high must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT150_533 Receiver Thresholds: Vdiff_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT150_533 Receiver Thresholds: Vdiff_dc must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT150_533 Receiver Thresholds: Tdiffslew_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT75_533 Receiver Thresholds: Vcross_low must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT75_533 Receiver Thresholds: Vcross_high must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT75_533 Receiver Thresholds: Vdiff_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT75_533 Receiver Thresholds: Vdiff_dc must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT75_533 Receiver Thresholds: Tdiffslew_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT50_533 Receiver Thresholds: Vcross_low must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT50_533 Receiver Thresholds: Vcross_high must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT50_533 Receiver Thresholds: Vdiff_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT50_533 Receiver Thresholds: Vdiff_dc must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_ODT50_533 Receiver Thresholds: Tdiffslew_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_533 Receiver Thresholds: Vcross_low must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_533 Receiver Thresholds: Vcross_high must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_533 Receiver Thresholds: Vdiff_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_533 Receiver Thresholds: Vdiff_dc must be specified for differential receivers (Pin 53)
WARNING - Model DQ_HALF_533 Receiver Thresholds: Tdiffslew_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT150_533 Receiver Thresholds: Vcross_low must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT150_533 Receiver Thresholds: Vcross_high must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT150_533 Receiver Thresholds: Vdiff_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT150_533 Receiver Thresholds: Vdiff_dc must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT150_533 Receiver Thresholds: Tdiffslew_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT75_533 Receiver Thresholds: Vcross_low must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT75_533 Receiver Thresholds: Vcross_high must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT75_533 Receiver Thresholds: Vdiff_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT75_533 Receiver Thresholds: Vdiff_dc must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT75_533 Receiver Thresholds: Tdiffslew_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT50_533 Receiver Thresholds: Vcross_low must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT50_533 Receiver Thresholds: Vcross_high must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT50_533 Receiver Thresholds: Vdiff_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT50_533 Receiver Thresholds: Vdiff_dc must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_ODT50_533 Receiver Thresholds: Tdiffslew_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_533 Receiver Thresholds: Vcross_low must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_533 Receiver Thresholds: Vcross_high must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_533 Receiver Thresholds: Vdiff_ac must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_533 Receiver Thresholds: Vdiff_dc must be specified for differential receivers (Pin 53)
WARNING - Model DQ_FULL_533 Receiver Thresholds: Tdiffslew_ac must be specified for differential receivers (Pin 53)