diff --git a/drivers/iommu/io-pgtable-arm-v7s.c b/drivers/iommu/io-pgtable-arm-v7s.c
index 69062945756563f1269f453052df0331d35ddd14..af330f513653d2849682b2d4536dd86dcb6a43d7 100644
--- a/drivers/iommu/io-pgtable-arm-v7s.c
+++ b/drivers/iommu/io-pgtable-arm-v7s.c
@@ -408,8 +408,12 @@ static arm_v7s_iopte arm_v7s_install_table(arm_v7s_iopte *table,
 	if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS)
 		new |= ARM_V7S_ATTR_NS_TABLE;
 
-	/* Ensure the table itself is visible before its PTE can be */
-	wmb();
+	/*
+	 * Ensure the table itself is visible before its PTE can be.
+	 * Whilst we could get away with cmpxchg64_release below, this
+	 * doesn't have any ordering semantics when !CONFIG_SMP.
+	 */
+	dma_wmb();
 
 	old = cmpxchg_relaxed(ptep, curr, new);
 	__arm_v7s_pte_sync(ptep, 1, cfg);
diff --git a/drivers/iommu/io-pgtable-arm.c b/drivers/iommu/io-pgtable-arm.c
index 52700fa958c209eadc39b7817b3ee6afecf443a8..b182039862c50debf8c55df4aad825cee468eed6 100644
--- a/drivers/iommu/io-pgtable-arm.c
+++ b/drivers/iommu/io-pgtable-arm.c
@@ -331,8 +331,12 @@ static arm_lpae_iopte arm_lpae_install_table(arm_lpae_iopte *table,
 	if (cfg->quirks & IO_PGTABLE_QUIRK_ARM_NS)
 		new |= ARM_LPAE_PTE_NSTABLE;
 
-	/* Ensure the table itself is visible before its PTE can be */
-	wmb();
+	/*
+	 * Ensure the table itself is visible before its PTE can be.
+	 * Whilst we could get away with cmpxchg64_release below, this
+	 * doesn't have any ordering semantics when !CONFIG_SMP.
+	 */
+	dma_wmb();
 
 	old = cmpxchg64_relaxed(ptep, curr, new);