Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 78 insertions, 0 deletions

diff --git a/kernel/arch/nios2/include/asm/checksum.h b/kernel/arch/nios2/include/asm/checksum.h
new file mode 100644
index 000000000..6bc1f0d5d
--- /dev/null
+++ b/kernel/arch/nios2/include/asm/checksum.h
@@ -0,0 +1,78 @@
+/*
+ * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
+ * Copyright (C) 2004 Microtronix Datacom Ltd.
+ *
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ */
+
+#ifndef _ASM_NIOS_CHECKSUM_H
+#define _ASM_NIOS_CHECKSUM_H
+
+/* Take these from lib/checksum.c */
+extern __wsum csum_partial(const void *buff, int len, __wsum sum);
+extern __wsum csum_partial_copy(const void *src, void *dst, int len,
+				__wsum sum);
+extern __wsum csum_partial_copy_from_user(const void __user *src, void *dst,
+					int len, __wsum sum, int *csum_err);
+#define csum_partial_copy_nocheck(src, dst, len, sum)	\
+	csum_partial_copy((src), (dst), (len), (sum))
+
+extern __sum16 ip_fast_csum(const void *iph, unsigned int ihl);
+extern __sum16 ip_compute_csum(const void *buff, int len);
+
+/*
+ * Fold a partial checksum
+ */
+static inline __sum16 csum_fold(__wsum sum)
+{
+	__asm__ __volatile__(
+		"add	%0, %1, %0\n"
+		"cmpltu	r8, %0, %1\n"
+		"srli	%0, %0, 16\n"
+		"add	%0, %0, r8\n"
+		"nor	%0, %0, %0\n"
+		: "=r" (sum)
+		: "r" (sum << 16), "0" (sum)
+		: "r8");
+	return (__force __sum16) sum;
+}
+
+/*
+ * computes the checksum of the TCP/UDP pseudo-header
+ * returns a 16-bit checksum, already complemented
+ */
+#define csum_tcpudp_nofold csum_tcpudp_nofold
+static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr,
+					unsigned short len,
+					unsigned short proto,
+					__wsum sum)
+{
+	__asm__ __volatile__(
+		"add	%0, %1, %0\n"
+		"cmpltu	r8, %0, %1\n"
+		"add	%0, %0, r8\n"	/* add carry */
+		"add	%0, %2, %0\n"
+		"cmpltu	r8, %0, %2\n"
+		"add	%0, %0, r8\n"	/* add carry */
+		"add	%0, %3, %0\n"
+		"cmpltu	r8, %0, %3\n"
+		"add	%0, %0, r8\n"	/* add carry */
+		: "=r" (sum), "=r" (saddr)
+		: "r" (daddr), "r" ((ntohs(len) << 16) + (proto * 256)),
+		  "0" (sum),
+		  "1" (saddr)
+		: "r8");
+
+	return sum;
+}
+
+static inline __sum16 csum_tcpudp_magic(__be32 saddr, __be32 daddr,
+					unsigned short len,
+					unsigned short proto, __wsum sum)
+{
+	return csum_fold(csum_tcpudp_nofold(saddr, daddr, len, proto, sum));
+}
+
+#endif /* _ASM_NIOS_CHECKSUM_H */