drivers/net/ethernet/netronome/nfp/nfpcore/crc32.h

   1 /*
   2  * Copyright (C) 2015-2017 Netronome Systems, Inc.
   3  *
   4  * This software is dual licensed under the GNU General License Version 2,
   5  * June 1991 as shown in the file COPYING in the top-level directory of this
   6  * source tree or the BSD 2-Clause License provided below.  You have the
   7  * option to license this software under the complete terms of either license.
   8  *
   9  * The BSD 2-Clause License:
  10  *
  11  *     Redistribution and use in source and binary forms, with or
  12  *     without modification, are permitted provided that the following
  13  *     conditions are met:
  14  *
  15  *      1. Redistributions of source code must retain the above
  16  *         copyright notice, this list of conditions and the following
  17  *         disclaimer.
  18  *
  19  *      2. Redistributions in binary form must reproduce the above
  20  *         copyright notice, this list of conditions and the following
  21  *         disclaimer in the documentation and/or other materials
  22  *         provided with the distribution.
  23  *
  24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31  * SOFTWARE.
  32  */
  33
  34 #ifndef NFP_CRC32_H
  35 #define NFP_CRC32_H
  36
  37 #include <linux/kernel.h>
  38 #include <linux/crc32.h>
  39
  40 /**
  41  * crc32_posix_end() - Finalize POSIX CRC32 working state
  42  * @crc:        Current CRC32 working state
  43  * @total_len:  Total length of data that was CRC32'd
  44  *
  45  * Return: Final POSIX CRC32 value
  46  */
  47 static inline u32 crc32_posix_end(u32 crc, size_t total_len)
  48 {
  49         /* Extend with the length of the string. */
  50         while (total_len != 0) {
  51                 u8 c = total_len & 0xff;
  52
  53                 crc = crc32_be(crc, &c, 1);
  54                 total_len >>= 8;
  55         }
  56
  57         return ~crc;
  58 }
  59
  60 static inline u32 crc32_posix(const void *buff, size_t len)
  61 {
  62         return crc32_posix_end(crc32_be(0, buff, len), len);
  63 }
  64
  65 #endif /* NFP_CRC32_H */