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checksum.h
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1 /*
2  * linux/arch/unicore32/include/asm/checksum.h
3  *
4  * Code specific to PKUnity SoC and UniCore ISA
5  *
6  * Copyright (C) 2001-2010 GUAN Xue-tao
7  *
8  * This program is free software; you can redistribute it and/or modify
9  * it under the terms of the GNU General Public License version 2 as
10  * published by the Free Software Foundation.
11  *
12  * IP checksum routines
13  */
14 #ifndef __UNICORE_CHECKSUM_H__
15 #define __UNICORE_CHECKSUM_H__
16 
17 /*
18  * computes the checksum of the TCP/UDP pseudo-header
19  * returns a 16-bit checksum, already complemented
20  */
21 
22 static inline __wsum
23 csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len,
24  unsigned short proto, __wsum sum)
25 {
26  __asm__(
27  "add.a %0, %1, %2\n"
28  "addc.a %0, %0, %3\n"
29  "addc.a %0, %0, %4 << #8\n"
30  "addc.a %0, %0, %5\n"
31  "addc %0, %0, #0\n"
32  : "=&r"(sum)
33  : "r" (sum), "r" (daddr), "r" (saddr), "r" (len), "Ir" (htons(proto))
34  : "cc");
35  return sum;
36 }
37 #define csum_tcpudp_nofold csum_tcpudp_nofold
38 
39 #include <asm-generic/checksum.h>
40 
41 #endif