[Feature]add MT2731_MP2_MR2_SVN388 baseline version

Change-Id: Ief04314834b31e27effab435d3ca8ba33b499059
diff --git a/src/kernel/linux/v4.14/arch/sparc/lib/ipcsum.S b/src/kernel/linux/v4.14/arch/sparc/lib/ipcsum.S
new file mode 100644
index 0000000..531d89c
--- /dev/null
+++ b/src/kernel/linux/v4.14/arch/sparc/lib/ipcsum.S
@@ -0,0 +1,36 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#include <linux/linkage.h>
+#include <asm/export.h>
+
+	.text
+ENTRY(ip_fast_csum) /* %o0 = iph, %o1 = ihl */
+	sub	%o1, 4, %g7
+	lduw	[%o0 + 0x00], %o2
+	lduw	[%o0 + 0x04], %g2
+	lduw	[%o0 + 0x08], %g3
+	addcc	%g2, %o2, %o2
+	lduw	[%o0 + 0x0c], %g2
+	addccc	%g3, %o2, %o2
+	lduw	[%o0 + 0x10], %g3
+
+	addccc	%g2, %o2, %o2
+	addc	%o2, %g0, %o2
+1:	addcc	%g3, %o2, %o2
+	add	%o0, 4, %o0
+	addccc	%o2, %g0, %o2
+	subcc	%g7, 1, %g7
+	be,a,pt	%icc, 2f
+	 sll	%o2, 16, %g2
+
+	lduw	[%o0 + 0x10], %g3
+	ba,pt	%xcc, 1b
+	 nop
+2:	addcc	%o2, %g2, %g2
+	srl	%g2, 16, %o2
+	addc	%o2, %g0, %o2
+	xnor	%g0, %o2, %o2
+	set	0xffff, %o1
+	retl
+	 and	%o2, %o1, %o0
+ENDPROC(ip_fast_csum)
+EXPORT_SYMBOL(ip_fast_csum)