iommu/arm-smmu: fix ARM_SMMU_FEAT_TRANS_OPS condition

This patch is a fix to "iommu/arm-smmu: add support for iova_to_phys
through ATS1PR".
According to ARM documentation, translation registers are optional even
in SMMUv1, so ID0_S1TS needs to be checked to verify their presence.
Also, we check that the domain is a stage-1 domain.
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Joerg Roedel <jroedel@suse.de>

drivers/iommu/arm-smmu.c

@@ -1288,10 +1288,13 @@ static phys_addr_t arm_smmu_iova_to_phys(struct iommu_domain *domain,
 		return 0;
 
 	spin_lock_irqsave(&smmu_domain->pgtbl_lock, flags);
-	if (smmu_domain->smmu->features & ARM_SMMU_FEAT_TRANS_OPS)
+	if (smmu_domain->smmu->features & ARM_SMMU_FEAT_TRANS_OPS &&
+			smmu_domain->stage == ARM_SMMU_DOMAIN_S1) {
 		ret = arm_smmu_iova_to_phys_hard(domain, iova);
-	else
+	} else {
 		ret = ops->iova_to_phys(ops, iova);
+	}
+
 	spin_unlock_irqrestore(&smmu_domain->pgtbl_lock, flags);
 
 	return ret;
@@ -1556,7 +1559,7 @@ static int arm_smmu_device_cfg_probe(struct arm_smmu_device *smmu)
 		return -ENODEV;
 	}
 
-	if (smmu->version == 1 || (!(id & ID0_ATOSNS) && (id & ID0_S1TS))) {
+	if ((id & ID0_S1TS) && ((smmu->version == 1) || (id & ID0_ATOSNS))) {
 		smmu->features |= ARM_SMMU_FEAT_TRANS_OPS;
 		dev_notice(smmu->dev, "\taddress translation ops\n");
 	}