diff --git a/arch/arm/mm/dma-mapping.c b/arch/arm/mm/dma-mapping.c
index d766e4256b74..4044abcf6f9d 100644
--- a/arch/arm/mm/dma-mapping.c
+++ b/arch/arm/mm/dma-mapping.c
@@ -1067,7 +1067,7 @@ static struct page **__iommu_alloc_buffer(struct device *dev, size_t size, gfp_t
 		return NULL;
 
 	while (count) {
-		int j, order = __ffs(count);
+		int j, order = __fls(count);
 
 		pages[i] = alloc_pages(gfp | __GFP_NOWARN, order);
 		while (!pages[i] && order)