linux/arch/tile/include/asm/checksum.h
<<
>>
Prefs
   1/*
   2 * Copyright 2010 Tilera Corporation. All Rights Reserved.
   3 *
   4 *   This program is free software; you can redistribute it and/or
   5 *   modify it under the terms of the GNU General Public License
   6 *   as published by the Free Software Foundation, version 2.
   7 *
   8 *   This program is distributed in the hope that it will be useful, but
   9 *   WITHOUT ANY WARRANTY; without even the implied warranty of
  10 *   MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or
  11 *   NON INFRINGEMENT.  See the GNU General Public License for
  12 *   more details.
  13 */
  14
  15#ifndef _ASM_TILE_CHECKSUM_H
  16#define _ASM_TILE_CHECKSUM_H
  17
  18#include <asm-generic/checksum.h>
  19
  20/* Allow us to provide a more optimized do_csum(). */
  21__wsum do_csum(const unsigned char *buff, int len);
  22#define do_csum do_csum
  23
  24/*
  25 * Return the sum of all the 16-bit subwords in a long.
  26 * This sums two subwords on a 32-bit machine, and four on 64 bits.
  27 * The implementation does two vector adds to capture any overflow.
  28 */
  29static inline unsigned int csum_long(unsigned long x)
  30{
  31        unsigned long ret;
  32#ifdef __tilegx__
  33        ret = __insn_v2sadu(x, 0);
  34        ret = __insn_v2sadu(ret, 0);
  35#else
  36        ret = __insn_sadh_u(x, 0);
  37        ret = __insn_sadh_u(ret, 0);
  38#endif
  39        return ret;
  40}
  41
  42#endif /* _ASM_TILE_CHECKSUM_H */
  43