[Feature]add MT2731_MP2_MR2_SVN388 baseline version

Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/arch/sh/lib/strlen.S b/src/kernel/linux/v4.14/arch/sh/lib/strlen.S
new file mode 100644
index 0000000..80ea53d
--- /dev/null
+++ b/src/kernel/linux/v4.14/arch/sh/lib/strlen.S
@@ -0,0 +1,71 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/* $Id: strlen.S,v 1.2 2001/06/29 14:07:15 gniibe Exp $
+ *
+ * "strlen" implementation of SuperH
+ *
+ * Copyright (C) 1999  Kaz Kojima
+ *
+ */
+
+/* size_t strlen (const char *s)  */
+
+#include <linux/linkage.h>
+ENTRY(strlen)
+	mov	r4,r0
+	and	#3,r0
+	tst	r0,r0
+	bt/s	1f
+	 mov	#0,r2
+
+	add	#-1,r0
+	shll2	r0
+	shll	r0
+	braf	r0
+	 nop
+
+	mov.b	@r4+,r1
+	tst	r1,r1
+	bt	8f
+	add	#1,r2
+
+	mov.b	@r4+,r1
+	tst	r1,r1
+	bt	8f
+	add	#1,r2
+
+	mov.b	@r4+,r1
+	tst	r1,r1
+	bt	8f
+	add	#1,r2
+
+1:
+	mov	#0,r3
+2:
+	mov.l	@r4+,r1
+	cmp/str	r3,r1
+	bf/s	2b
+	 add	#4,r2
+
+	add	#-4,r2
+#ifndef __LITTLE_ENDIAN__
+	swap.b	r1,r1
+	swap.w	r1,r1
+	swap.b	r1,r1
+#endif
+	extu.b	r1,r0
+	tst	r0,r0
+	bt/s	8f
+	 shlr8	r1
+	add	#1,r2
+	extu.b	r1,r0
+	tst	r0,r0
+	bt/s	8f
+	 shlr8	r1
+	add	#1,r2
+	extu.b	r1,r0
+	tst	r0,r0
+	bt	8f
+	add	#1,r2
+8:
+	rts
+	 mov	r2,r0