diff --git a/arch/sparc/mm/sun4c.c b/arch/sparc/mm/sun4c.c
index 1d560390e28212346bae398e3c87e8e619aa253d..731f19603cad719951c7a180fd3c9ca136b55fd6 100644
--- a/arch/sparc/mm/sun4c.c
+++ b/arch/sparc/mm/sun4c.c
@@ -497,7 +497,7 @@ static void __init sun4c_probe_mmu(void)
 	patch_kernel_fault_handler();
 }
 
-volatile unsigned long *sun4c_memerr_reg = NULL;
+volatile unsigned long __iomem *sun4c_memerr_reg = NULL;
 
 void __init sun4c_probe_memerr_reg(void)
 {
diff --git a/include/asm-sparc/memreg.h b/include/asm-sparc/memreg.h
index c0498d3baf931fe71c8d656b4146844a471d67dc..5fb95c828da6760582fe95f93ff5ddf683fc73c7 100644
--- a/include/asm-sparc/memreg.h
+++ b/include/asm-sparc/memreg.h
@@ -36,7 +36,7 @@
 
 /* Memory parity error register with associated bit constants. */
 #ifndef __ASSEMBLY__
-extern __volatile__ unsigned long *sun4c_memerr_reg;
+extern __volatile__ unsigned long __iomem *sun4c_memerr_reg;
 #endif
 
 #define	SUN4C_MPE_ERROR	0x80	/* Parity error detected. (ro) */