1 #ifndef _ASM_CRIS_ARCH_CHECKSUM_H
2 #define _ASM_CRIS_ARCH_CHECKSUM_H
5 * Check values used in TCP/UDP headers.
7 * The gain of doing this in assembler instead of C, is that C doesn't
8 * generate carry-additions for the 32-bit components of the
9 * checksum. Which means it would be necessary to split all those into
10 * 16-bit components and then add.
12 static inline unsigned int
13 csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr,
14 unsigned short len, unsigned short proto, unsigned int sum)
18 __asm__ __volatile__ ("add.d %2, %0\n\t"
23 : "0" (sum), "r" (daddr), "r" (saddr), \
24 "r" ((ntohs(len) << 16) + (proto << 8)));
29 #endif /* _ASM_CRIS_ARCH_CHECKSUM_H */