LXR uboot/lib/crc32.c

   1/*
   2 * This file is derived from crc32.c from the zlib-1.1.3 distribution
   3 * by Jean-loup Gailly and Mark Adler.
   4 */
   5
   6/* crc32.c -- compute the CRC-32 of a data stream
   7 * Copyright (C) 1995-1998 Mark Adler
   8 * For conditions of distribution and use, see copyright notice in zlib.h
   9 */
  10
  11#ifndef USE_HOSTCC
  12#include <common.h>
  13#endif
  14#include <compiler.h>
  15#include <u-boot/crc.h>
  16
  17#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
  18#include <watchdog.h>
  19#endif
  20#include "u-boot/zlib.h"
  21
  22#define local static
  23#define ZEXPORT /* empty */
  24
  25#define tole(x) cpu_to_le32(x)
  26
  27#ifdef DYNAMIC_CRC_TABLE
  28
  29local int crc_table_empty = 1;
  30local uint32_t crc_table[256];
  31local void make_crc_table OF((void));
  32
  33/*
  34  Generate a table for a byte-wise 32-bit CRC calculation on the polynomial:
  35  x^32+x^26+x^23+x^22+x^16+x^12+x^11+x^10+x^8+x^7+x^5+x^4+x^2+x+1.
  36
  37  Polynomials over GF(2) are represented in binary, one bit per coefficient,
  38  with the lowest powers in the most significant bit.  Then adding polynomials
  39  is just exclusive-or, and multiplying a polynomial by x is a right shift by
  40  one.  If we call the above polynomial p, and represent a byte as the
  41  polynomial q, also with the lowest power in the most significant bit (so the
  42  byte 0xb1 is the polynomial x^7+x^3+x+1), then the CRC is (q*x^32) mod p,
  43  where a mod b means the remainder after dividing a by b.
  44
  45  This calculation is done using the shift-register method of multiplying and
  46  taking the remainder.  The register is initialized to zero, and for each
  47  incoming bit, x^32 is added mod p to the register if the bit is a one (where
  48  x^32 mod p is p+x^32 = x^26+...+1), and the register is multiplied mod p by
  49  x (which is shifting right by one and adding x^32 mod p if the bit shifted
  50  out is a one).  We start with the highest power (least significant bit) of
  51  q and repeat for all eight bits of q.
  52
  53  The table is simply the CRC of all possible eight bit values.  This is all
  54  the information needed to generate CRC's on data a byte at a time for all
  55  combinations of CRC register values and incoming bytes.
  56*/
  57local void make_crc_table()
  58{
  59  uint32_t c;
  60  int n, k;
  61  uLong poly;           /* polynomial exclusive-or pattern */
  62  /* terms of polynomial defining this crc (except x^32): */
  63  static const Byte p[] = {0,1,2,4,5,7,8,10,11,12,16,22,23,26};
  64
  65  /* make exclusive-or pattern from polynomial (0xedb88320L) */
  66  poly = 0L;
  67  for (n = 0; n < sizeof(p)/sizeof(Byte); n++)
  68    poly |= 1L << (31 - p[n]);
  69
  70  for (n = 0; n < 256; n++)
  71  {
  72    c = (uLong)n;
  73    for (k = 0; k < 8; k++)
  74      c = c & 1 ? poly ^ (c >> 1) : c >> 1;
  75    crc_table[n] = tole(c);
  76  }
  77  crc_table_empty = 0;
  78}
  79#else
  80/* ========================================================================
  81 * Table of CRC-32's of all single-byte values (made by make_crc_table)
  82 */
  83
  84local const uint32_t crc_table[256] = {
  85tole(0x00000000L), tole(0x77073096L), tole(0xee0e612cL), tole(0x990951baL),
  86tole(0x076dc419L), tole(0x706af48fL), tole(0xe963a535L), tole(0x9e6495a3L),
  87tole(0x0edb8832L), tole(0x79dcb8a4L), tole(0xe0d5e91eL), tole(0x97d2d988L),
  88tole(0x09b64c2bL), tole(0x7eb17cbdL), tole(0xe7b82d07L), tole(0x90bf1d91L),
  89tole(0x1db71064L), tole(0x6ab020f2L), tole(0xf3b97148L), tole(0x84be41deL),
  90tole(0x1adad47dL), tole(0x6ddde4ebL), tole(0xf4d4b551L), tole(0x83d385c7L),
  91tole(0x136c9856L), tole(0x646ba8c0L), tole(0xfd62f97aL), tole(0x8a65c9ecL),
  92tole(0x14015c4fL), tole(0x63066cd9L), tole(0xfa0f3d63L), tole(0x8d080df5L),
  93tole(0x3b6e20c8L), tole(0x4c69105eL), tole(0xd56041e4L), tole(0xa2677172L),
  94tole(0x3c03e4d1L), tole(0x4b04d447L), tole(0xd20d85fdL), tole(0xa50ab56bL),
  95tole(0x35b5a8faL), tole(0x42b2986cL), tole(0xdbbbc9d6L), tole(0xacbcf940L),
  96tole(0x32d86ce3L), tole(0x45df5c75L), tole(0xdcd60dcfL), tole(0xabd13d59L),
  97tole(0x26d930acL), tole(0x51de003aL), tole(0xc8d75180L), tole(0xbfd06116L),
  98tole(0x21b4f4b5L), tole(0x56b3c423L), tole(0xcfba9599L), tole(0xb8bda50fL),
  99tole(0x2802b89eL), tole(0x5f058808L), tole(0xc60cd9b2L), tole(0xb10be924L),
 100tole(0x2f6f7c87L), tole(0x58684c11L), tole(0xc1611dabL), tole(0xb6662d3dL),
 101tole(0x76dc4190L), tole(0x01db7106L), tole(0x98d220bcL), tole(0xefd5102aL),
 102tole(0x71b18589L), tole(0x06b6b51fL), tole(0x9fbfe4a5L), tole(0xe8b8d433L),
 103tole(0x7807c9a2L), tole(0x0f00f934L), tole(0x9609a88eL), tole(0xe10e9818L),
 104tole(0x7f6a0dbbL), tole(0x086d3d2dL), tole(0x91646c97L), tole(0xe6635c01L),
 105tole(0x6b6b51f4L), tole(0x1c6c6162L), tole(0x856530d8L), tole(0xf262004eL),
 106tole(0x6c0695edL), tole(0x1b01a57bL), tole(0x8208f4c1L), tole(0xf50fc457L),
 107tole(0x65b0d9c6L), tole(0x12b7e950L), tole(0x8bbeb8eaL), tole(0xfcb9887cL),
 108tole(0x62dd1ddfL), tole(0x15da2d49L), tole(0x8cd37cf3L), tole(0xfbd44c65L),
 109tole(0x4db26158L), tole(0x3ab551ceL), tole(0xa3bc0074L), tole(0xd4bb30e2L),
 110tole(0x4adfa541L), tole(0x3dd895d7L), tole(0xa4d1c46dL), tole(0xd3d6f4fbL),
 111tole(0x4369e96aL), tole(0x346ed9fcL), tole(0xad678846L), tole(0xda60b8d0L),
 112tole(0x44042d73L), tole(0x33031de5L), tole(0xaa0a4c5fL), tole(0xdd0d7cc9L),
 113tole(0x5005713cL), tole(0x270241aaL), tole(0xbe0b1010L), tole(0xc90c2086L),
 114tole(0x5768b525L), tole(0x206f85b3L), tole(0xb966d409L), tole(0xce61e49fL),
 115tole(0x5edef90eL), tole(0x29d9c998L), tole(0xb0d09822L), tole(0xc7d7a8b4L),
 116tole(0x59b33d17L), tole(0x2eb40d81L), tole(0xb7bd5c3bL), tole(0xc0ba6cadL),
 117tole(0xedb88320L), tole(0x9abfb3b6L), tole(0x03b6e20cL), tole(0x74b1d29aL),
 118tole(0xead54739L), tole(0x9dd277afL), tole(0x04db2615L), tole(0x73dc1683L),
 119tole(0xe3630b12L), tole(0x94643b84L), tole(0x0d6d6a3eL), tole(0x7a6a5aa8L),
 120tole(0xe40ecf0bL), tole(0x9309ff9dL), tole(0x0a00ae27L), tole(0x7d079eb1L),
 121tole(0xf00f9344L), tole(0x8708a3d2L), tole(0x1e01f268L), tole(0x6906c2feL),
 122tole(0xf762575dL), tole(0x806567cbL), tole(0x196c3671L), tole(0x6e6b06e7L),
 123tole(0xfed41b76L), tole(0x89d32be0L), tole(0x10da7a5aL), tole(0x67dd4accL),
 124tole(0xf9b9df6fL), tole(0x8ebeeff9L), tole(0x17b7be43L), tole(0x60b08ed5L),
 125tole(0xd6d6a3e8L), tole(0xa1d1937eL), tole(0x38d8c2c4L), tole(0x4fdff252L),
 126tole(0xd1bb67f1L), tole(0xa6bc5767L), tole(0x3fb506ddL), tole(0x48b2364bL),
 127tole(0xd80d2bdaL), tole(0xaf0a1b4cL), tole(0x36034af6L), tole(0x41047a60L),
 128tole(0xdf60efc3L), tole(0xa867df55L), tole(0x316e8eefL), tole(0x4669be79L),
 129tole(0xcb61b38cL), tole(0xbc66831aL), tole(0x256fd2a0L), tole(0x5268e236L),
 130tole(0xcc0c7795L), tole(0xbb0b4703L), tole(0x220216b9L), tole(0x5505262fL),
 131tole(0xc5ba3bbeL), tole(0xb2bd0b28L), tole(0x2bb45a92L), tole(0x5cb36a04L),
 132tole(0xc2d7ffa7L), tole(0xb5d0cf31L), tole(0x2cd99e8bL), tole(0x5bdeae1dL),
 133tole(0x9b64c2b0L), tole(0xec63f226L), tole(0x756aa39cL), tole(0x026d930aL),
 134tole(0x9c0906a9L), tole(0xeb0e363fL), tole(0x72076785L), tole(0x05005713L),
 135tole(0x95bf4a82L), tole(0xe2b87a14L), tole(0x7bb12baeL), tole(0x0cb61b38L),
 136tole(0x92d28e9bL), tole(0xe5d5be0dL), tole(0x7cdcefb7L), tole(0x0bdbdf21L),
 137tole(0x86d3d2d4L), tole(0xf1d4e242L), tole(0x68ddb3f8L), tole(0x1fda836eL),
 138tole(0x81be16cdL), tole(0xf6b9265bL), tole(0x6fb077e1L), tole(0x18b74777L),
 139tole(0x88085ae6L), tole(0xff0f6a70L), tole(0x66063bcaL), tole(0x11010b5cL),
 140tole(0x8f659effL), tole(0xf862ae69L), tole(0x616bffd3L), tole(0x166ccf45L),
 141tole(0xa00ae278L), tole(0xd70dd2eeL), tole(0x4e048354L), tole(0x3903b3c2L),
 142tole(0xa7672661L), tole(0xd06016f7L), tole(0x4969474dL), tole(0x3e6e77dbL),
 143tole(0xaed16a4aL), tole(0xd9d65adcL), tole(0x40df0b66L), tole(0x37d83bf0L),
 144tole(0xa9bcae53L), tole(0xdebb9ec5L), tole(0x47b2cf7fL), tole(0x30b5ffe9L),
 145tole(0xbdbdf21cL), tole(0xcabac28aL), tole(0x53b39330L), tole(0x24b4a3a6L),
 146tole(0xbad03605L), tole(0xcdd70693L), tole(0x54de5729L), tole(0x23d967bfL),
 147tole(0xb3667a2eL), tole(0xc4614ab8L), tole(0x5d681b02L), tole(0x2a6f2b94L),
 148tole(0xb40bbe37L), tole(0xc30c8ea1L), tole(0x5a05df1bL), tole(0x2d02ef8dL)
 149};
 150#endif
 151
 152#if 0
 153/* =========================================================================
 154 * This function can be used by asm versions of crc32()
 155 */
 156const uint32_t * ZEXPORT get_crc_table()
 157{
 158#ifdef DYNAMIC_CRC_TABLE
 159  if (crc_table_empty) make_crc_table();
 160#endif
 161  return (const uint32_t *)crc_table;
 162}
 163#endif
 164
 165/* ========================================================================= */
 166# if __BYTE_ORDER == __LITTLE_ENDIAN
 167#  define DO_CRC(x) crc = tab[(crc ^ (x)) & 255] ^ (crc >> 8)
 168# else
 169#  define DO_CRC(x) crc = tab[((crc >> 24) ^ (x)) & 255] ^ (crc << 8)
 170# endif
 171
 172/* ========================================================================= */
 173
 174/* No ones complement version. JFFS2 (and other things ?)
 175 * don't use ones compliment in their CRC calculations.
 176 */
 177uint32_t ZEXPORT crc32_no_comp(uint32_t crc, const Bytef *buf, uInt len)
 178{
 179    const uint32_t *tab = crc_table;
 180    const uint32_t *b =(const uint32_t *)buf;
 181    size_t rem_len;
 182#ifdef DYNAMIC_CRC_TABLE
 183    if (crc_table_empty)
 184      make_crc_table();
 185#endif
 186    crc = cpu_to_le32(crc);
 187    /* Align it */
 188    if (((long)b) & 3 && len) {
 189         uint8_t *p = (uint8_t *)b;
 190         do {
 191              DO_CRC(*p++);
 192         } while ((--len) && ((long)p)&3);
 193         b = (uint32_t *)p;
 194    }
 195
 196    rem_len = len & 3;
 197    len = len >> 2;
 198    for (--b; len; --len) {
 199         /* load data 32 bits wide, xor data 32 bits wide. */
 200         crc ^= *++b; /* use pre increment for speed */
 201         DO_CRC(0);
 202         DO_CRC(0);
 203         DO_CRC(0);
 204         DO_CRC(0);
 205    }
 206    len = rem_len;
 207    /* And the last few bytes */
 208    if (len) {
 209         uint8_t *p = (uint8_t *)(b + 1) - 1;
 210         do {
 211              DO_CRC(*++p); /* use pre increment for speed */
 212         } while (--len);
 213    }
 214
 215    return le32_to_cpu(crc);
 216}
 217#undef DO_CRC
 218
 219uint32_t ZEXPORT crc32 (uint32_t crc, const Bytef *p, uInt len)
 220{
 221     return crc32_no_comp(crc ^ 0xffffffffL, p, len) ^ 0xffffffffL;
 222}
 223
 224/*
 225 * Calculate the crc32 checksum triggering the watchdog every 'chunk_sz' bytes
 226 * of input.
 227 */
 228uint32_t ZEXPORT crc32_wd (uint32_t crc,
 229                           const unsigned char *buf,
 230                           uInt len, uInt chunk_sz)
 231{
 232#if defined(CONFIG_HW_WATCHDOG) || defined(CONFIG_WATCHDOG)
 233        const unsigned char *end, *curr;
 234        int chunk;
 235
 236        curr = buf;
 237        end = buf + len;
 238        while (curr < end) {
 239                chunk = end - curr;
 240                if (chunk > chunk_sz)
 241                        chunk = chunk_sz;
 242                crc = crc32 (crc, curr, chunk);
 243                curr += chunk;
 244                WATCHDOG_RESET ();
 245        }
 246#else
 247        crc = crc32 (crc, buf, len);
 248#endif
 249
 250        return crc;
 251}
 252