--- a/arch/mips/alchemy/common/clock.c
+++ b/arch/mips/alchemy/common/clock.c
@@ -128,6 +128,8 @@
 		t = 396000000;
 	else {
 		t = alchemy_rdsys(AU1000_SYS_CPUPLL) & 0x7f;
+		if (alchemy_get_cputype() != ALCHEMY_CPU_AU1300)
+			t &= 0x3f;
 		t *= parent_rate;
 	}