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1 #ifndef _CRIS_ARCH_CHECKSUM_H
2 #define _CRIS_ARCH_CHECKSUM_H
3 
4 /* Checksum some values used in TCP/UDP headers.
5  *
6  * The gain by doing this in asm is that C will not generate carry-additions
7  * for the 32-bit components of the checksum, so otherwise we would have had
8  * to split all of those into 16-bit components, then add.
9  */
10 
11 static inline __wsum
csum_tcpudp_nofold(__be32 saddr,__be32 daddr,unsigned short len,unsigned short proto,__wsum sum)12 csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len,
13 		   unsigned short proto, __wsum sum)
14 {
15 	__wsum res;
16 	__asm__ ("add.d %2, %0\n\t"
17 		 "ax\n\t"
18 		 "add.d %3, %0\n\t"
19 		 "ax\n\t"
20 		 "add.d %4, %0\n\t"
21 		 "ax\n\t"
22 		 "addq 0, %0\n"
23 	: "=r" (res)
24 	: "0" (sum), "r" (daddr), "r" (saddr), "r" ((len + proto) << 8));
25 
26 	return res;
27 }
28 
29 #endif
30