diff --git a/arch/nios2/include/asm/io.h b/arch/nios2/include/asm/io.h
index d0adf08..e7da35b 100644
--- a/arch/nios2/include/asm/io.h
+++ b/arch/nios2/include/asm/io.h
@@ -39,7 +39,11 @@
 
 static inline phys_addr_t virt_to_phys(void * vaddr)
 {
-	return (phys_addr_t)(vaddr);
+	DECLARE_GLOBAL_DATA_PTR;
+	if (gd->arch.has_mmu)
+		return (phys_addr_t)vaddr & 0x1fffffff;
+	else
+		return (phys_addr_t)vaddr & 0x7fffffff;
 }
 
 static inline void *ioremap(unsigned long physaddr, unsigned long size)