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#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 unsigned int
csum_tcpudp_nofold(unsigned long saddr, unsigned long daddr,
unsigned short len, unsigned short proto, unsigned int sum)
{
int 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" ((ntohs(len) << 16) + (proto << 8)));
return res;
}
#endif /* _ASM_CRIS_ARCH_CHECKSUM_H */
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