diff --git a/drivers/iommu/dma-iommu.c b/drivers/iommu/dma-iommu.c
index f68a62c3c32b55e1414ee5eff0cc34a452f38489..ef407e4eccdeae3fcfde0401b2affbaa63f5558a 100644
--- a/drivers/iommu/dma-iommu.c
+++ b/drivers/iommu/dma-iommu.c
@@ -1086,6 +1086,13 @@ static int iommu_dma_get_sgtable(struct device *dev, struct sg_table *sgt,
 	return ret;
 }
 
+static unsigned long iommu_dma_get_merge_boundary(struct device *dev)
+{
+	struct iommu_domain *domain = iommu_get_dma_domain(dev);
+
+	return (1UL << __ffs(domain->pgsize_bitmap)) - 1;
+}
+
 static const struct dma_map_ops iommu_dma_ops = {
 	.alloc			= iommu_dma_alloc,
 	.free			= iommu_dma_free,
@@ -1101,6 +1108,7 @@ static const struct dma_map_ops iommu_dma_ops = {
 	.sync_sg_for_device	= iommu_dma_sync_sg_for_device,
 	.map_resource		= iommu_dma_map_resource,
 	.unmap_resource		= iommu_dma_unmap_resource,
+	.get_merge_boundary	= iommu_dma_get_merge_boundary,
 };
 
 /*