ECC算法c代码

/*****************************************************************************/ /* */ /* PROJECT : SAMSUNG ECC */ /* FILE : SAMSUNG_ECC.c */ /* PURPOSE : This file implements core ECC algorithms adopted */ /* Hamming Error Correction and Detection Algorithm */ /* */ /*---------------------------------------------------------------------------*/ /* */ /* COPYRIGHT 2000-2004, SAMSUNG ELECTRONICS CO., LTD. */ /* ALL RIGHTS RESERVED */ /* */ /* Permission is hereby granted to licensees of Samsung Electronics */ /* Co., Ltd. products to use or abstract this computer program for the */ /* sole purpose of implementing a product based on Samsung */ /* Electronics Co., Ltd. products. No other rights to reproduce, use, */ /* or disseminate this computer program, whether in part or in whole, */ /* are granted. */ /* */ /* Samsung Electronics Co., Ltd. makes no representation or warranties */ /* with respect to the performance of this computer program, and */ /* specifically disclaims any responsibility for any damages, */ /* special or consequential, connected with the use of this program. */ /* */ /*---------------------------------------------------------------------------*/ /* */ /* REVISION HISTORY */ /* */ /* 13-NOV-2003 [Chang JongBaek] : first writing */ /* 03-MAR-2004 [ Kim YoungGon ] : Second writing */ /* 03-MAR-2004 [ Lee JaeBum ] : Third writing */ /*---------------------------------------------------------------------------*/ /* */ /* NOTES */ /* */ /* - Make ECC parity code of 512bytes(256words) and 3 bytes are represented */ /* And ECC compare & Correction code is also represented */ /* */ /*****************************************************************************/ #include <stdio.h> #include <conio.h> #include <stdlib.h> #include <string.h> //#include "ecc.h" #define XMODE 8 /*****************************************************************************/ /* Address Types */ /*****************************************************************************/ typedef unsigned char * address_t; /* address (pointer) */ typedef unsigned long address_value_t; /* address (for calculation) */ /*****************************************************************************/ /* Integer Types */ /*****************************************************************************/ typedef unsigned long uint32_t; /* unsigned 4 byte integer */ typedef signed long int32_t; /* signed 4 byte integer */ typedef unsigned short uint16_t; /* unsigned 2 byte integer */ typedef signed short int16_t; /* signed 2 byte integer */ typedef unsigned char uint8_t; /* unsigned 1 byte integer */ typedef signed char int8_t; /* signed 1 byte integer */ typedef enum { ECC_NO_ERROR = 0, /* no error */ ECC_CORRECTABLE_ERROR = 1, /* one bit data error */ ECC_ECC_ERROR = 2, /* one bit ECC error */ ECC_UNCORRECTABLE_ERROR = 3 /* uncorrectable error */ } eccdiff_t; /*****************************************************************************/ /* */ /* NAME */ /* make_ecc_512 */ /* DESCRIPTION */ /* This function generates 3 byte ECC for 512 byte data. */ /* (Software ECC) */ /* PARAMETERS */ /* ecc_buf the location where ECC should be stored */ /* data_buf given data */ /* RETURN VALUES */ /* none */ /* */ /*****************************************************************************/ #if (XMODE == 8) void make_ecc_512(uint8_t * ecc_buf, uint8_t * data_buf) #else void make_ecc_512(uint16_t * ecc_buf, uint16_t * data_buf) #endif { uint32_t i, ALIGN_FACTOR; uint32_t tmp; uint32_t uiparity = 0; uint32_t parityCol, ecc = 0; uint32_t parityCol4321 = 0, parityCol4343 = 0, parityCol4242 = 0, parityColTot = 0; uint32_t *Data; uint32_t Xorbit=0; ALIGN_FACTOR = (uint32_t)data_buf % 4 ; Data = (uint32_t *)(data_buf + ALIGN_FACTOR); for( i = 0; i < 16; i++) { parityCol = *Data++; tmp = *Data++; parityCol ^= tmp; parityCol4242 ^= tmp; tmp = *Data++; parityCol ^= tmp; parityCol4343 ^= tmp; tmp = *Data++; parityCol ^= tmp; parityCol4343 ^= tmp; parityCol4242 ^= tmp; tmp = *Data++; parityCol ^= tmp; parityCol4321 ^= tmp; tmp = *Data++; parityCol ^= tmp; parityCol4242 ^= tmp; parityCol4321 ^= tmp; tmp = *Data++; parityCol ^= tmp; parityCol4343 ^= tmp; parityCol4321 ^= tmp; tmp = *Data++; parityCol ^= tmp; parityCol4242 ^= tmp; parityCol4343 ^= tmp; parityCol4321 ^= tmp; parityColTot ^= parityCol; tmp = (parityCol >> 16) ^ parityCol; tmp = (tmp >> 8) ^ tmp; tmp = (tmp >> 4) ^ tmp; tmp = ((tmp >> 2) ^ tmp) & 0x03; if ((tmp == 0x01) || (tmp == 0x02)) { uiparity ^= i; Xorbit ^= 0x01; } } #if (XMODE == 8) tmp = (parityCol4321 >> 16) ^ parityCol4321; tmp = (tmp << 8) ^ tmp; tmp = (tmp >> 4) ^ tmp; tmp = (tmp >> 2) ^ tmp; ecc |= ((tmp << 1) ^ tmp) & 0x200; // p128 #else tmp = (parityCol4321 >> 16) ^ parityCol4321; tmp = (tmp >> 8) ^ tmp; tmp = (tmp << 4) ^ tmp; tmp = (tmp << 2) ^ tmp; ecc |= ((tmp << 1) ^ tmp) & 0x80; // p128 #endif #if (XMODE == 8) tmp = (parityCol4343 >> 16) ^ parityCol4343; tmp = (tmp >> 8) ^ tmp; tmp = (tmp << 4) ^ tmp; tmp = (tmp << 2) ^ tmp; ecc |= ((tmp << 1) ^ tmp) & 0x80; // p64 #else tmp = (parityCol4343 >> 16) ^ parityCol4343; tmp = (tmp >> 8) ^ tmp; tmp = (tmp << 4) ^ tmp; tmp = (tmp >> 2) ^ tmp; ecc |= ((tmp << 1) ^ tmp) & 0x20; // p64 #endif #if (XMODE == 8) tmp = (parityCol4242 >> 16) ^ parityCol4242; tmp = (tmp >> 8) ^ tmp; tmp = (tmp << 4) ^ tmp; tmp = (tmp >> 2) ^ tmp; ecc |= ((tmp << 1) ^ tmp) & 0x20; // p32 #else tmp = (parityCol4242 >> 16) ^ parityCol4242; tmp = (tmp >> 8) ^ tmp; tmp = (tmp >> 4) ^ tmp; tmp = (tmp << 2) ^ tmp; ecc |= ((tmp