diff --git a/arch/sparc64/kernel/iommu.c b/arch/sparc64/kernel/iommu.c
index b781d3d..756fa24 100644
--- a/arch/sparc64/kernel/iommu.c
+++ b/arch/sparc64/kernel/iommu.c
@@ -516,9 +516,11 @@
 	unsigned long flags, handle, prot, ctx;
 	dma_addr_t dma_next = 0, dma_addr;
 	unsigned int max_seg_size;
+	unsigned long seg_boundary_size;
 	int outcount, incount, i;
 	struct strbuf *strbuf;
 	struct iommu *iommu;
+	unsigned long base_shift;
 
 	BUG_ON(direction == DMA_NONE);
 
@@ -549,8 +551,11 @@
 	outs->dma_length = 0;
 
 	max_seg_size = dma_get_max_seg_size(dev);
+	seg_boundary_size = ALIGN(dma_get_seg_boundary(dev) + 1,
+				  IO_PAGE_SIZE) >> IO_PAGE_SHIFT;
+	base_shift = iommu->page_table_map_base >> IO_PAGE_SHIFT;
 	for_each_sg(sglist, s, nelems, i) {
-		unsigned long paddr, npages, entry, slen;
+		unsigned long paddr, npages, entry, out_entry = 0, slen;
 		iopte_t *base;
 
 		slen = s->length;
@@ -593,7 +598,9 @@
 			 * - allocated dma_addr isn't contiguous to previous allocation
 			 */
 			if ((dma_addr != dma_next) ||
-			    (outs->dma_length + s->length > max_seg_size)) {
+			    (outs->dma_length + s->length > max_seg_size) ||
+			    (is_span_boundary(out_entry, base_shift,
+					      seg_boundary_size, outs, s))) {
 				/* Can't merge: create a new segment */
 				segstart = s;
 				outcount++;
@@ -607,6 +614,7 @@
 			/* This is a new segment, fill entries */
 			outs->dma_address = dma_addr;
 			outs->dma_length = slen;
+			out_entry = entry;
 		}
 
 		/* Calculate next page pointer for contiguous check */
diff --git a/arch/sparc64/kernel/iommu_common.h b/arch/sparc64/kernel/iommu_common.h
index 0713bd5..87ace49 100644
--- a/arch/sparc64/kernel/iommu_common.h
+++ b/arch/sparc64/kernel/iommu_common.h
@@ -12,6 +12,7 @@
 #include <linux/mm.h>
 #include <linux/scatterlist.h>
 #include <linux/device.h>
+#include <linux/iommu-helper.h>
 
 #include <asm/iommu.h>
 #include <asm/scatterlist.h>
@@ -58,6 +59,18 @@
 	return npages;
 }
 
+static inline int is_span_boundary(unsigned long entry,
+				   unsigned long shift,
+				   unsigned long boundary_size,
+				   struct scatterlist *outs,
+				   struct scatterlist *sg)
+{
+	unsigned long paddr = SG_ENT_PHYS_ADDRESS(outs);
+	int nr = iommu_num_pages(paddr, outs->dma_length + sg->length);
+
+	return iommu_is_span_boundary(entry, nr, shift, boundary_size);
+}
+
 extern unsigned long iommu_range_alloc(struct device *dev,
 				       struct iommu *iommu,
 				       unsigned long npages,
diff --git a/arch/sparc64/kernel/pci_sun4v.c b/arch/sparc64/kernel/pci_sun4v.c
index ddca6c6..0183970 100644
--- a/arch/sparc64/kernel/pci_sun4v.c
+++ b/arch/sparc64/kernel/pci_sun4v.c
@@ -335,8 +335,10 @@
 	unsigned long flags, handle, prot;
 	dma_addr_t dma_next = 0, dma_addr;
 	unsigned int max_seg_size;
+	unsigned long seg_boundary_size;
 	int outcount, incount, i;
 	struct iommu *iommu;
+	unsigned long base_shift;
 	long err;
 
 	BUG_ON(direction == DMA_NONE);
@@ -362,8 +364,11 @@
 	iommu_batch_start(dev, prot, ~0UL);
 
 	max_seg_size = dma_get_max_seg_size(dev);
+	seg_boundary_size = ALIGN(dma_get_seg_boundary(dev) + 1,
+				  IO_PAGE_SIZE) >> IO_PAGE_SHIFT;
+	base_shift = iommu->page_table_map_base >> IO_PAGE_SHIFT;
 	for_each_sg(sglist, s, nelems, i) {
-		unsigned long paddr, npages, entry, slen;
+		unsigned long paddr, npages, entry, out_entry = 0, slen;
 
 		slen = s->length;
 		/* Sanity check */
@@ -406,7 +411,9 @@
 			 * - allocated dma_addr isn't contiguous to previous allocation
 			 */
 			if ((dma_addr != dma_next) ||
-			    (outs->dma_length + s->length > max_seg_size)) {
+			    (outs->dma_length + s->length > max_seg_size) ||
+			    (is_span_boundary(out_entry, base_shift,
+					      seg_boundary_size, outs, s))) {
 				/* Can't merge: create a new segment */
 				segstart = s;
 				outcount++;
@@ -420,6 +427,7 @@
 			/* This is a new segment, fill entries */
 			outs->dma_address = dma_addr;
 			outs->dma_length = slen;
+			out_entry = entry;
 		}
 
 		/* Calculate next page pointer for contiguous check */