/* This file has been prepared for Doxygen automatic documentation generation.*/
/**
 * \file
 *
 * \brief Functions for computing 32- and 16-bit CRC for EEPROM and Flash.
 *
 * \par Application note:
 *      AVR1610: Guide to IEC60730 Class B compliance with XMEGA
 *
 * \par Documentation
 *      For comprehensive code documentation, supported compilers, compiler 
 *      settings and supported devices see readme.html
 *
 * \author
 *      Atmel Corporation: http://www.atmel.com \n
 *      Support email: avr@atmel.com
 * 
 * Copyright (C) 2012 Atmel Corporation. All rights reserved.
 *
 * \page License
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 * this list of conditions and the following disclaimer in the documentation
 * and/or other materials provided with the distribution.
 *
 * 3. The name of Atmel may not be used to endorse or promote products derived
 * from this software without specific prior written permission.
 *
 * 4. This software may only be redistributed and used in connection with an
 * Atmel AVR product.
 *
 * THIS SOFTWARE IS PROVIDED BY ATMEL "AS IS" AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
 * EXPRESSLY AND SPECIFICALLY DISCLAIMED. IN NO EVENT SHALL ATMEL BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 */

//! \ingroup classb_crc_sw
//@{
 
#include "classb_crc_sw.h"


/******************* CRC16 Functions ******************/

#if (defined(CLASSB_CRC_USE_SW) && defined(CLASSB_CRC_16_BIT)) || defined(__DOXYGEN__)

#if defined(CRC_USE_16BIT_LOOKUP_TABLE) || defined(__DOXYGEN__)

//! Table for CCITT 16-bit CRC, stored in Flash
const uint16_t PROGMEM_DECLARE( CLASSB_CRC16Table[256] ) = {
    0x0000, 0x1021, 0x2042, 0x3063, 0x4084, 0x50A5, 0x60C6, 0x70E7,
    0x8108, 0x9129, 0xA14A, 0xB16B, 0xC18C, 0xD1AD, 0xE1CE, 0xF1EF,
    0x1231, 0x0210, 0x3273, 0x2252, 0x52B5, 0x4294, 0x72F7, 0x62D6,
    0x9339, 0x8318, 0xB37B, 0xA35A, 0xD3BD, 0xC39C, 0xF3FF, 0xE3DE,
    0x2462, 0x3443, 0x0420, 0x1401, 0x64E6, 0x74C7, 0x44A4, 0x5485,
    0xA56A, 0xB54B, 0x8528, 0x9509, 0xE5EE, 0xF5CF, 0xC5AC, 0xD58D,
    0x3653, 0x2672, 0x1611, 0x0630, 0x76D7, 0x66F6, 0x5695, 0x46B4,
    0xB75B, 0xA77A, 0x9719, 0x8738, 0xF7DF, 0xE7FE, 0xD79D, 0xC7BC,
    0x48C4, 0x58E5, 0x6886, 0x78A7, 0x0840, 0x1861, 0x2802, 0x3823,
    0xC9CC, 0xD9ED, 0xE98E, 0xF9AF, 0x8948, 0x9969, 0xA90A, 0xB92B,
    0x5AF5, 0x4AD4, 0x7AB7, 0x6A96, 0x1A71, 0x0A50, 0x3A33, 0x2A12,
    0xDBFD, 0xCBDC, 0xFBBF, 0xEB9E, 0x9B79, 0x8B58, 0xBB3B, 0xAB1A,
    0x6CA6, 0x7C87, 0x4CE4, 0x5CC5, 0x2C22, 0x3C03, 0x0C60, 0x1C41,
    0xEDAE, 0xFD8F, 0xCDEC, 0xDDCD, 0xAD2A, 0xBD0B, 0x8D68, 0x9D49,
    0x7E97, 0x6EB6, 0x5ED5, 0x4EF4, 0x3E13, 0x2E32, 0x1E51, 0x0E70,
    0xFF9F, 0xEFBE, 0xDFDD, 0xCFFC, 0xBF1B, 0xAF3A, 0x9F59, 0x8F78,
    0x9188, 0x81A9, 0xB1CA, 0xA1EB, 0xD10C, 0xC12D, 0xF14E, 0xE16F,
    0x1080, 0x00A1, 0x30C2, 0x20E3, 0x5004, 0x4025, 0x7046, 0x6067,
    0x83B9, 0x9398, 0xA3FB, 0xB3DA, 0xC33D, 0xD31C, 0xE37F, 0xF35E,
    0x02B1, 0x1290, 0x22F3, 0x32D2, 0x4235, 0x5214, 0x6277, 0x7256,
    0xB5EA, 0xA5CB, 0x95A8, 0x8589, 0xF56E, 0xE54F, 0xD52C, 0xC50D,
    0x34E2, 0x24C3, 0x14A0, 0x0481, 0x7466, 0x6447, 0x5424, 0x4405,
    0xA7DB, 0xB7FA, 0x8799, 0x97B8, 0xE75F, 0xF77E, 0xC71D, 0xD73C,
    0x26D3, 0x36F2, 0x0691, 0x16B0, 0x6657, 0x7676, 0x4615, 0x5634,
    0xD94C, 0xC96D, 0xF90E, 0xE92F, 0x99C8, 0x89E9, 0xB98A, 0xA9AB,
    0x5844, 0x4865, 0x7806, 0x6827, 0x18C0, 0x08E1, 0x3882, 0x28A3,
    0xCB7D, 0xDB5C, 0xEB3F, 0xFB1E, 0x8BF9, 0x9BD8, 0xABBB, 0xBB9A,
    0x4A75, 0x5A54, 0x6A37, 0x7A16, 0x0AF1, 0x1AD0, 0x2AB3, 0x3A92,
    0xFD2E, 0xED0F, 0xDD6C, 0xCD4D, 0xBDAA, 0xAD8B, 0x9DE8, 0x8DC9,
    0x7C26, 0x6C07, 0x5C64, 0x4C45, 0x3CA2, 0x2C83, 0x1CE0, 0x0CC1,
    0xEF1F, 0xFF3E, 0xCF5D, 0xDF7C, 0xAF9B, 0xBFBA, 0x8FD9, 0x9FF8,
    0x6E17, 0x7E36, 0x4E55, 0x5E74, 0x2E93, 0x3EB2, 0x0ED1, 0x1EF0
};
#endif //defined(CRC_USE_16BIT_LOOKUP_TABLE)


/*! \brief Compute 16-bit CRC for EEPROM address range using table lookup.
 *
 * This function returns the 16-bit CRC of the specified EEPROM address range.
 *
 * \param origDataptr Address of EEPROM location to start CRC computation at.
 * \param numBytes    Number of bytes of the data.
 * \param pchecksum	  Pointer to the checksum stored in EEPROM.
 *
 * \note No sanity checking of addresses is done.
 */
uint16_t CLASSB_CRC16_EEPROM_SW (eepromptr_t origDataptr, crcbytenum_t numBytes, eeprom_uint16ptr_t pchecksum)
{
    eeprom_uint8ptr_t dataptr = origDataptr;
    uint16_t remainder = CRC16_INITIAL_REMAINDER;
    uint8_t dataTemp;

    // Ensure that EEPROM is memory mapped.
    CLASSB_EEMAP_BEGIN();
    dataptr += MAPPED_EEPROM_START;

    // Compute CRC for the specified data.
    for (; numBytes != 0; numBytes--) 
	{
        dataTemp = *dataptr++;

#ifdef CRC_USE_16BIT_LOOKUP_TABLE
		CLASSB_CRC_TABLE_16(dataTemp, remainder, CLASSB_CRC16Table);
#else
		CLASSB_CRC(dataTemp, remainder, CRC16_POLYNOMIAL, 16);
#endif
    }
	
	#if defined(__ICCAVR__)	
	 // Disable memory mapping of EEPROM, if necessary.
     CLASSB_EEMAP_END();
	 // Compare checksums and handle error if necessary.
	 if ( remainder != *pchecksum) 
		 CLASSB_ERROR_HANDLER_CRC();
	#elif defined(__GCC__)
	 // Compare checksums and handle error if necessary.
	 if ( remainder != *(eeprom_uint32ptr_t)(MAPPED_EEPROM_START + (uintptr_t) pchecksum)) 
	  	 CLASSB_ERROR_HANDLER_CRC();
	 // Disable memory mapping of EEPROM, if necessary.
     CLASSB_EEMAP_END();
	#endif

    return (remainder);
}


/*! \brief Compute 16-bit CRC for Flash address range using table lookup.
 *
 * This function returns the 16-bit CRC of the specified Flash address range.
 *
 * \param origDataptr Address of Flash location to start CRC computation at.
 * \param numBytes    Number of bytes of the data.
 * \param pchecksum	  Pointer to the checksum stored in EEPROM.
 *
 * \note No sanity checking of addresses is done.
 */
uint16_t CLASSB_CRC16_Flash_SW (flashptr_t origDataptr, crcbytenum_t numBytes, eeprom_uint16ptr_t pchecksum)
{
    flash_uint8ptr_t dataptr = origDataptr;
    uint16_t remainder = CRC16_INITIAL_REMAINDER;
    uint8_t dataTemp;
    
    // Compute CRC for the specified data.
    for (; numBytes != 0; numBytes--) 
	{

#if (PROGMEM_SIZE >= 0x10000UL) 
		 dataTemp = PROGMEM_READ_BYTE_FAR(dataptr++);
#else
         dataTemp = PROGMEM_READ_BYTE(dataptr++);
#endif		

#if defined(CRC_USE_16BIT_LOOKUP_TABLE)
		CLASSB_CRC_TABLE_16(dataTemp, remainder, CLASSB_CRC16Table);
#else
		CLASSB_CRC(dataTemp, remainder, CRC16_POLYNOMIAL, 16);
#endif
    }

	#if defined(__ICCAVR__)	
	 // Compare checksums and handle error if necessary.
	 if ( remainder != *pchecksum) 
		 CLASSB_ERROR_HANDLER_CRC();
	#elif defined(__GCC__)
	 // Ensure that EEPROM is memory mapped.
	 CLASSB_EEMAP_BEGIN();
	 // Compare checksums and handle error if necessary.
	 if ( remainder != *(eeprom_uint16ptr_t)(MAPPED_EEPROM_START + (uintptr_t) pchecksum)) 
	  	 CLASSB_ERROR_HANDLER_CRC();
	 // Disable memory mapping of EEPROM, if necessary.
	 CLASSB_EEMAP_END();
	#endif

    return (remainder);
}
#endif // defined(CLASSB_CRC_USE_SW) && defined(CLASSB_CRC_16_BIT)



/******************* CRC32 Functions ******************/
#if (defined(CLASSB_CRC_USE_SW) && defined(CLASSB_CRC_32_BIT)) || defined(__DOXYGEN__)

#if defined(CRC_USE_32BIT_LOOKUP_TABLE) || defined(__DOXYGEN__)

//! Table for IEE802.3 32-bit CRC, stored in Flash 
const uint32_t PROGMEM_DECLARE( CLASSB_CRC32Table[256] ) = {
    0x00000000, 0x77073096, 0xEE0E612C, 0x990951BA,
	0x076DC419, 0x706AF48F, 0xE963A535, 0x9E6495A3,
	0x0EDB8832, 0x79DCB8A4, 0xE0D5E91E, 0x97D2D988,
	0x09B64C2B, 0x7EB17CBD, 0xE7B82D07, 0x90BF1D91,
	0x1DB71064, 0x6AB020F2, 0xF3B97148, 0x84BE41DE,
	0x1ADAD47D, 0x6DDDE4EB, 0xF4D4B551, 0x83D385C7,
	0x136C9856, 0x646BA8C0, 0xFD62F97A, 0x8A65C9EC,
	0x14015C4F, 0x63066CD9, 0xFA0F3D63, 0x8D080DF5,
	0x3B6E20C8, 0x4C69105E, 0xD56041E4, 0xA2677172,
	0x3C03E4D1, 0x4B04D447, 0xD20D85FD, 0xA50AB56B,
	0x35B5A8FA, 0x42B2986C, 0xDBBBC9D6, 0xACBCF940,
	0x32D86CE3, 0x45DF5C75, 0xDCD60DCF, 0xABD13D59,
	0x26D930AC, 0x51DE003A, 0xC8D75180, 0xBFD06116,
	0x21B4F4B5, 0x56B3C423, 0xCFBA9599, 0xB8BDA50F,
	0x2802B89E, 0x5F058808, 0xC60CD9B2, 0xB10BE924,
	0x2F6F7C87, 0x58684C11, 0xC1611DAB, 0xB6662D3D,
	0x76DC4190, 0x01DB7106, 0x98D220BC, 0xEFD5102A,
	0x71B18589, 0x06B6B51F, 0x9FBFE4A5, 0xE8B8D433,
	0x7807C9A2, 0x0F00F934, 0x9609A88E, 0xE10E9818,
	0x7F6A0DBB, 0x086D3D2D, 0x91646C97, 0xE6635C01,
	0x6B6B51F4, 0x1C6C6162, 0x856530D8, 0xF262004E,
	0x6C0695ED, 0x1B01A57B, 0x8208F4C1, 0xF50FC457,
	0x65B0D9C6, 0x12B7E950, 0x8BBEB8EA, 0xFCB9887C,
	0x62DD1DDF, 0x15DA2D49, 0x8CD37CF3, 0xFBD44C65,
	0x4DB26158, 0x3AB551CE, 0xA3BC0074, 0xD4BB30E2,
	0x4ADFA541, 0x3DD895D7, 0xA4D1C46D, 0xD3D6F4FB,
	0x4369E96A, 0x346ED9FC, 0xAD678846, 0xDA60B8D0,
	0x44042D73, 0x33031DE5, 0xAA0A4C5F, 0xDD0D7CC9,
	0x5005713C, 0x270241AA, 0xBE0B1010, 0xC90C2086,
	0x5768B525, 0x206F85B3, 0xB966D409, 0xCE61E49F,
	0x5EDEF90E, 0x29D9C998, 0xB0D09822, 0xC7D7A8B4,
	0x59B33D17, 0x2EB40D81, 0xB7BD5C3B, 0xC0BA6CAD,
	0xEDB88320, 0x9ABFB3B6, 0x03B6E20C, 0x74B1D29A,
	0xEAD54739, 0x9DD277AF, 0x04DB2615, 0x73DC1683,
	0xE3630B12, 0x94643B84, 0x0D6D6A3E, 0x7A6A5AA8,
	0xE40ECF0B, 0x9309FF9D, 0x0A00AE27, 0x7D079EB1,
	0xF00F9344, 0x8708A3D2, 0x1E01F268, 0x6906C2FE,
	0xF762575D, 0x806567CB, 0x196C3671, 0x6E6B06E7,
	0xFED41B76, 0x89D32BE0, 0x10DA7A5A, 0x67DD4ACC,
	0xF9B9DF6F, 0x8EBEEFF9, 0x17B7BE43, 0x60B08ED5,
	0xD6D6A3E8, 0xA1D1937E, 0x38D8C2C4, 0x4FDFF252,
	0xD1BB67F1, 0xA6BC5767, 0x3FB506DD, 0x48B2364B,
	0xD80D2BDA, 0xAF0A1B4C, 0x36034AF6, 0x41047A60,
	0xDF60EFC3, 0xA867DF55, 0x316E8EEF, 0x4669BE79,
	0xCB61B38C, 0xBC66831A, 0x256FD2A0, 0x5268E236,
	0xCC0C7795, 0xBB0B4703, 0x220216B9, 0x5505262F,
	0xC5BA3BBE, 0xB2BD0B28, 0x2BB45A92, 0x5CB36A04,
	0xC2D7FFA7, 0xB5D0CF31, 0x2CD99E8B, 0x5BDEAE1D,
	0x9B64C2B0, 0xEC63F226, 0x756AA39C, 0x026D930A,
	0x9C0906A9, 0xEB0E363F, 0x72076785, 0x05005713,
	0x95BF4A82, 0xE2B87A14, 0x7BB12BAE, 0x0CB61B38,
	0x92D28E9B, 0xE5D5BE0D, 0x7CDCEFB7, 0x0BDBDF21,
	0x86D3D2D4, 0xF1D4E242, 0x68DDB3F8, 0x1FDA836E,
	0x81BE16CD, 0xF6B9265B, 0x6FB077E1, 0x18B74777,
	0x88085AE6, 0xFF0F6A70, 0x66063BCA, 0x11010B5C,
	0x8F659EFF, 0xF862AE69, 0x616BFFD3, 0x166CCF45,
	0xA00AE278, 0xD70DD2EE, 0x4E048354, 0x3903B3C2,
	0xA7672661, 0xD06016F7, 0x4969474D, 0x3E6E77DB,
	0xAED16A4A, 0xD9D65ADC, 0x40DF0B66, 0x37D83BF0,
	0xA9BCAE53, 0xDEBB9EC5, 0x47B2CF7F, 0x30B5FFE9,
	0xBDBDF21C, 0xCABAC28A, 0x53B39330, 0x24B4A3A6,
	0xBAD03605, 0xCDD70693, 0x54DE5729, 0x23D967BF,
	0xB3667A2E, 0xC4614AB8, 0x5D681B02, 0x2A6F2B94,
	0xB40BBE37, 0xC30C8EA1, 0x5A05DF1B, 0x2D02EF8D
};
#endif //defined(CRC_USE_32BIT_LOOKUP_TABLE)


/*! \brief Compute 32-bit CRC for EEPROM address range using table lookup.
 *
 * This function returns the 32-bit CRC of the specified EEPROM address range.
 *
 * \param origDataptr Address of EEPROM location to start CRC computation at.
 * \param numBytes    Number of bytes of the data.
 * \param pchecksum	  Pointer to the checksum stored in EEPROM.
 * 
 * \note No sanity checking of addresses is done.
 */
uint32_t CLASSB_CRC32_EEPROM_SW (eepromptr_t origDataptr, crcbytenum_t numBytes, eeprom_uint32ptr_t pchecksum)
{
    eeprom_uint8ptr_t dataptr = origDataptr;
    uint32_t remainder = CRC32_INITIAL_REMAINDER;
    uint8_t dataTemp;
    
    // Ensure that EEPROM is memory mapped.
    CLASSB_EEMAP_BEGIN();
    dataptr += MAPPED_EEPROM_START;

    // Compute CRC for the specified data.
    for (; numBytes != 0; numBytes--) 
	{
        dataTemp = *dataptr++;
#if defined(CRC_USE_32BIT_LOOKUP_TABLE)
		CLASSB_CRC_REFL_TABLE_32(dataTemp, remainder, CLASSB_CRC32Table);
#else
		CLASSB_CRC_REFL(dataTemp, remainder, CRC32_POLYNOMIAL, 32);
#endif
    }
    
#ifdef CRC32_FINAL_XOR_VALUE
	remainder ^= CRC32_FINAL_XOR_VALUE;
#endif	
	
	#if defined(__ICCAVR__)	
	 // Disable memory mapping of EEPROM, if necessary.
     CLASSB_EEMAP_END();
	 // Compare checksums and handle error if necessary.
	 if ( remainder != *pchecksum) 
		 CLASSB_ERROR_HANDLER_CRC();
	#elif defined(__GCC__)
	 // Compare checksums and handle error if necessary.
	 if ( remainder != *(eeprom_uint32ptr_t)(MAPPED_EEPROM_START + (uintptr_t) pchecksum)) 
	  	 CLASSB_ERROR_HANDLER_CRC();
	 // Disable memory mapping of EEPROM, if necessary.
     CLASSB_EEMAP_END();
	#endif

    return (remainder);
}


/*! \brief Compute 32-bit CRC for Flash address range using table lookup.
 *
 * This function returns the 32-bit CRC of the specified Flash address range.
 *
 * \param origDataptr Address of Flash location to start CRC computation at.
 * \param numBytes    Number of bytes of the data.
 * \param pchecksum	  Pointer to the checksum stored in EEPROM.
 *
 * \note No sanity checking of addresses is done.
 */
uint32_t CLASSB_CRC32_Flash_SW (flashptr_t origDataptr, crcbytenum_t numBytes, eeprom_uint32ptr_t pchecksum)
{
    flash_uint8ptr_t dataptr = origDataptr;
    uint32_t remainder = CRC32_INITIAL_REMAINDER;
    uint8_t dataTemp;

    // Compute CRC for the specified data.
    for (; numBytes != 0; numBytes--) 
	{
        
#if (PROGMEM_SIZE >= 0x10000UL) 
		 dataTemp = PROGMEM_READ_BYTE_FAR(dataptr++);
#else
         dataTemp = PROGMEM_READ_BYTE(dataptr++);
#endif
		
#if defined(CRC_USE_32BIT_LOOKUP_TABLE)
		CLASSB_CRC_REFL_TABLE_32(dataTemp, remainder, CLASSB_CRC32Table);
#else
		CLASSB_CRC_REFL(dataTemp, remainder, CRC32_POLYNOMIAL, 32);
#endif

    }
	
#ifdef CRC32_FINAL_XOR_VALUE	
	remainder ^= CRC32_FINAL_XOR_VALUE;
#endif	

	#if defined(__ICCAVR__)	
	 // Compare checksums and handle error if necessary.
	 if ( remainder != *pchecksum) 
		 CLASSB_ERROR_HANDLER_CRC();
	#elif defined(__GCC__)
	 // Ensure that EEPROM is memory mapped.
	 CLASSB_EEMAP_BEGIN();
	 // Compare checksums and handle error if necessary.
	 if ( remainder != *(eeprom_uint32ptr_t)(MAPPED_EEPROM_START + (uintptr_t) pchecksum)) 
	  	 CLASSB_ERROR_HANDLER_CRC();
	 // Disable memory mapping of EEPROM, if necessary.
	 CLASSB_EEMAP_END();
	#endif

    return (remainder);
}


#endif // defined(CLASSB_CRC_USE_SW) && defined(CLASSB_CRC_32_BIT)
//@}