lib/crc8.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  * Copyright (c) 2013 Google, Inc
   4  */
   5
   6 #ifdef USE_HOSTCC
   7 #include <arpa/inet.h>
   8 #endif
   9 #include <asm/sections.h>
  10 #include <u-boot/crc.h>
  11
  12 #define POLY    (0x1070U << 3)
  13
  14 __rcode static unsigned char _crc8(unsigned short data)
  15 {
  16         int i;
  17
  18         for (i = 0; i < 8; i++) {
  19                 if (data & 0x8000)
  20                         data = data ^ POLY;
  21                 data = data << 1;
  22         }
  23
  24         return (unsigned char)(data >> 8);
  25 }
  26
  27 __rcode unsigned int crc8(unsigned int crc, const unsigned char *vptr, int len)
  28 {
  29         int i;
  30
  31         for (i = 0; i < len; i++)
  32                 crc = _crc8((crc ^ vptr[i]) << 8);
  33
  34         return crc;
  35 }
  36
  37 void crc8_wd_buf(const unsigned char *input, unsigned int len,
  38                  unsigned char output[1], unsigned int chunk_sz)
  39 {
  40         *output = crc8(0, input, len);
  41 }