diff --git a/arch/mips/cpu/start.S b/arch/mips/cpu/start.S
index 827a544987852587a1ca7018e2a160c4b71b19ca..6aec430a670ceb3223b92fd5ab70600e70eacbc0 100644
--- a/arch/mips/cpu/start.S
+++ b/arch/mips/cpu/start.S
@@ -123,8 +123,9 @@ reset:
 	mtc0	zero, CP0_COMPARE
 
 #ifndef CONFIG_SKIP_LOWLEVEL_INIT
-	/* CONFIG0 register */
-	li	t0, CONF_CM_UNCACHED
+	mfc0	t0, CP0_CONFIG
+	and	t0, t0, MIPS_CONF_IMPL
+	or	t0, t0, CONF_CM_UNCACHED
 	mtc0	t0, CP0_CONFIG
 #endif
 
diff --git a/arch/mips/include/asm/mipsregs.h b/arch/mips/include/asm/mipsregs.h
index 3185dc7abf2048d3ea4d917c678333d04b63509c..cd4f952df0af2419865b2aa048a8ecfdb0bfcb62 100644
--- a/arch/mips/include/asm/mipsregs.h
+++ b/arch/mips/include/asm/mipsregs.h
@@ -450,6 +450,7 @@
 #define MIPS_CONF_MT_FTLB	(_ULCAST_(4) <<  7)
 #define MIPS_CONF_AR		(_ULCAST_(7) << 10)
 #define MIPS_CONF_AT		(_ULCAST_(3) << 13)
+#define MIPS_CONF_IMPL		(_ULCAST_(0x1ff) << 16)
 #define MIPS_CONF_M		(_ULCAST_(1) << 31)
 
 /*