diff --git a/drivers/iommu/arm-smmu-v3.c b/drivers/iommu/arm-smmu-v3.c index c2c1ad8915d9..4f093373f4c3 100644 --- a/drivers/iommu/arm-smmu-v3.c +++ b/drivers/iommu/arm-smmu-v3.c @@ -2054,9 +2054,17 @@ static int arm_smmu_init_strtab_2lvl(struct arm_smmu_device *smmu) int ret; struct arm_smmu_strtab_cfg *cfg = &smmu->strtab_cfg; - /* Calculate the L1 size, capped to the SIDSIZE */ - size = STRTAB_L1_SZ_SHIFT - (ilog2(STRTAB_L1_DESC_DWORDS) + 3); - size = min(size, smmu->sid_bits - STRTAB_SPLIT); + /* + * If we can resolve everything with a single L2 table, then we + * just need a single L1 descriptor. Otherwise, calculate the L1 + * size, capped to the SIDSIZE. + */ + if (smmu->sid_bits < STRTAB_SPLIT) { + size = 0; + } else { + size = STRTAB_L1_SZ_SHIFT - (ilog2(STRTAB_L1_DESC_DWORDS) + 3); + size = min(size, smmu->sid_bits - STRTAB_SPLIT); + } cfg->num_l1_ents = 1 << size; size += STRTAB_SPLIT;