#ifndef _ASM_CRIS_ARCH_CHECKSUM_H #define _ASM_CRIS_ARCH_CHECKSUM_H /* * Check values used in TCP/UDP headers. * * The gain of doing this in assembler instead of C, is that C doesn't * generate carry-additions for the 32-bit components of the * checksum. Which means it would be necessary to split all those into * 16-bit components and then add. */ static inline __wsum csum_tcpudp_nofold(__be32 saddr, __be32 daddr, unsigned short len, unsigned short proto, __wsum sum) { __wsum res; __asm__ __volatile__ ("add.d %2, %0\n\t" "addc %3, %0\n\t" "addc %4, %0\n\t" "addc 0, %0\n\t" : "=r" (res) : "0" (sum), "r" (daddr), "r" (saddr), \ "r" ((len + proto) << 8)); return res; } #endif /* _ASM_CRIS_ARCH_CHECKSUM_H */