ARM_SMMU_GR0_S2CR
last_s2cr = ARM_SMMU_GR0_S2CR(127);
last_s2cr = ARM_SMMU_GR0_S2CR(smmu->num_mapping_groups - 1);
arm_smmu_gr0_write(smmu, ARM_SMMU_GR0_S2CR(idx), reg);
arm_smmu_gr0_write(smmu, ARM_SMMU_GR0_S2CR(idx), reg);