regVCN_UMSCH_RB_DB_CTRL
data = RREG32_SOC15(VCN, 0, regVCN_UMSCH_RB_DB_CTRL);
WREG32_SOC15(VCN, 0, regVCN_UMSCH_RB_DB_CTRL, data);
data = RREG32_SOC15(VCN, 0, regVCN_UMSCH_RB_DB_CTRL);
WREG32_SOC15(VCN, 0, regVCN_UMSCH_RB_DB_CTRL, data);