diff options
Diffstat (limited to 'arch/tile/include/asm/checksum.h')
| -rw-r--r-- | arch/tile/include/asm/checksum.h | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/arch/tile/include/asm/checksum.h b/arch/tile/include/asm/checksum.h index a120766c7264..b21a2fdec9f7 100644 --- a/arch/tile/include/asm/checksum.h +++ b/arch/tile/include/asm/checksum.h @@ -21,4 +21,22 @@ __wsum do_csum(const unsigned char *buff, int len); #define do_csum do_csum +/* + * Return the sum of all the 16-bit subwords in a long. + * This sums two subwords on a 32-bit machine, and four on 64 bits. + * The implementation does two vector adds to capture any overflow. + */ +static inline unsigned int csum_long(unsigned long x) +{ + unsigned long ret; +#ifdef __tilegx__ + ret = __insn_v2sadu(x, 0); + ret = __insn_v2sadu(ret, 0); +#else + ret = __insn_sadh_u(x, 0); + ret = __insn_sadh_u(ret, 0); +#endif + return ret; +} + #endif /* _ASM_TILE_CHECKSUM_H */ |