/*! @file srec.c * FILE:   $Id:$ * * DESCRIPTION: *     This is a light weight Motorola SREC decoder.  The following SREC types *     are supported. *         Type 0 - SREC START *         Type 1 - SREC DATA 1 *         Type 2 - SREC DATA 2 *         Type 3 - SREC DATA 3 *         Type 7 - SREC END TYPE 3 *         Type 8 - SREC END TYPE 2 *         Type 9 - SREC END TYPE 1 * *     Refer to the Motorola SREC documentation for SREC format. * * AUTHOR: *     John Williams, PetaLogix <John.Williams@petalogix.com> * * MODIFICATION: *     Benny Chen, PetaLogix <Benny.Chen@petalogix.com> * * LICENSING: *     Copyright (c) 2006 PetaLogix. All rights reserved. * *  No part of this program may be reproduced or adapted in  any form  or by *  any means, electronic or mechanical, without  permission from PetaLogix. *  This program is  confidential and  may not be  disclosed, decompiled  or *  reverse engineered without permission in writing from PetaLogix. * *//*! * Check if ASCII character is a digit *  * @param  ASCII character * * @return  Return 1 if is digit */static int isdigit(char x){    if(x >= '0' && x <= '9') {        return 1;    } else {        return 0;    }}static int isupper(char x){    if(x >= 'A' && x <= 'F') {        return 1;    } else {        return 0;    }}static int islower(char x){    if(x >= 'a' && x <= 'f') {        return 1;    } else {        return 0;    }}/*! * Return the hex equivalent value of the ASCII characer *  * @param  ASCII character * * @return  Return the hex value */unsigned char nybble_to_val(char x){	if(isdigit(x))		return x-'0';	else if(isupper(x))		return x-'A'+10;	else if(islower(x))		return x-'a'+10;	else		return -1;}	int grab_hex_byte(char *buffer){	return nybble_to_val(buffer[0])*16 + nybble_to_val(buffer[1]);}unsigned int grab_hex_word(char *buffer){	return grab_hex_byte(buffer)*256 + grab_hex_byte(buffer+2);}unsigned int grab_hex_dword(char *buffer){	return grab_hex_word(buffer)*65536 + grab_hex_word(buffer+4);}/*! * Given a SREC line, parse the line and return the information associated * with the SREC. *  * @param  buffer - pointer to SREC line. * @param  binlen - pointer to storage for the data length. * @param  addr -   pointer to the address at which the data is to be written  *                  in memory. * @param  data -   Pointer to the buffer to store the binary data. * * @return  The SREC type. */int decode_srec_line(char *buffer, int *binlen, unsigned long *addr,                                                      unsigned char *data){	int type, data_count, i;         unsigned int ch = 0;        int inc = 0;        unsigned char cksum = 0;        /* Start from the first S */        for(; *buffer; buffer++) {            /* Found our S */	    if(*buffer =='S') {                /* Move to the next byte */                buffer++;                break;            }        }        /* Check if there is any data */        if(*buffer == '\0') {            /* return an invalid type for empty record */            return 99;        }         /* Get the type */	type = *buffer -'0';        buffer++;        /* Get our count in bytes - 1 byte field */	if((*binlen = grab_hex_byte(buffer)) < 0) {            /* Invalid count field */            return -1;        }        /* Increment to start of address field */        buffer += 2;        /* Initialise our check sum */        cksum = *binlen;	data_count=0;	switch(type)	{	case 0: /* Type Start */	case 1:	/* Type 1 */                /*  checksum = 1 byte, Address field = 2 bytes */                *binlen -= 3;                /* Get our 2 bytes address field */                *addr = (unsigned long)grab_hex_word(buffer);                /* Increment to start of data field */                inc = 2;		break;	case 2: /* Type 2 */                /*  checksum = 1 byte, Address field = 3 bytes */                *binlen -= 4;                *addr = (unsigned long)grab_hex_word(buffer);                *addr = (*addr << 8) | grab_hex_byte(buffer + 4);                inc = 3;                break;	case 3: /* Type 3 */                /*  checksum = 1 byte, Address field = 4 bytes */                *binlen -= 5;                /* Get our 4 bytes address field */                *addr = (unsigned long)grab_hex_dword(buffer);                /* Increment to start of data field */                inc = 4;		break;        case 7: /* SREC End for Type 3 */                /* No data field */                *binlen = 0;                *addr = (unsigned long)grab_hex_dword(buffer);                inc = 4;                break;        case 8: /* SREC End for Type 2 */                /* No data field */                *binlen = 0;                *addr = (unsigned long)grab_hex_word(buffer);                *addr = (*addr << 8) | grab_hex_byte(buffer + 4);                inc = 3;                break;        case 9: /* SREC End for Type 1 */                /* No data field */                *binlen = 0;                *addr = (unsigned long)grab_hex_word(buffer);                inc = 2;                break;	default:                /* Invalid or not supported type */                return -1;	}        /* Update the cksum and increment to start of data */        for(i = 0; i < inc; i++) {            cksum += grab_hex_byte(buffer);            buffer += 2;        }        /* Copy data */	if((data_count = *binlen))	{		while(data_count--)		{			ch = grab_hex_byte(buffer);                        *data = (unsigned char) ch;                        data++;                        cksum += ch;                        buffer += 2;		}	}        /* Get the checksum - 1 byte */        if((ch = grab_hex_byte(buffer)) < 0) {            /* No checksum found */            return -1;        }                /* Compare the checksum */        if((unsigned char) ch != (unsigned char)~cksum) {            /* Checksum don't match */            //xil_printf("DEBUG: Checksum failed: Expect:0x%x, Got:0x%x\n\r",            //           (unsigned char) ch, (unsigned char)~cksum);             return -1;        }	return type;}