diff --git a/arch/mips/include/asm/mach-ralink/ralink_regs.h b/arch/mips/include/asm/mach-ralink/ralink_regs.h
index 5a508f9f94320ed6776d8dc5216b294ab4011905..bd93014490df39eebce2df057d5b3e84f2130aeb 100644
--- a/arch/mips/include/asm/mach-ralink/ralink_regs.h
+++ b/arch/mips/include/asm/mach-ralink/ralink_regs.h
@@ -26,6 +26,13 @@ static inline u32 rt_sysc_r32(unsigned reg)
 	return __raw_readl(rt_sysc_membase + reg);
 }
 
+static inline void rt_sysc_m32(u32 clr, u32 set, unsigned reg)
+{
+	u32 val = rt_sysc_r32(reg) & ~clr;
+
+	__raw_writel(val | set, rt_sysc_membase + reg);
+}
+
 static inline void rt_memc_w32(u32 val, unsigned reg)
 {
 	__raw_writel(val, rt_memc_membase + reg);