eeupd_block.S

/* Copyright (c) 2009  Dmitry Xmelkov
   All rights reserved.

   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions are met:

   * Redistributions of source code must retain the above copyright
     notice, this list of conditions and the following disclaimer.
   * 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.
   * Neither the name of the copyright holders nor the names of
     contributors may be used to endorse or promote products derived
     from this software without specific prior written permission.

   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS 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.  */

/* $Id$ */

#ifndef __DOXYGEN__

#include <avr/io.h>

#if E2END && __AVR_ARCH__ > 1

#include <avr/eeprom.h>
#include "asmdef.h"
#include "eedef.h"

/* void eeprom_update_block (const void *sram, void *eepr, size_t n)
 */

#define sram_lo r24
#define eepr_lo r22

ENTRY   eeprom_update_block

#if RAMEND > 0xFF  ||  E2END > 0xFF
    X_movw  XL, sram_lo
    add XL, n_lo
    adc XH, n_hi
    subi    n_lo, lo8(1)
    sbci    n_hi, hi8(1)
#else
    mov XL, sram_lo
    add XL, n_lo
    subi    n_lo, lo8(1)
#endif
    brlo    3f

#if E2END > 0xFF
    X_movw  addr_lo, eepr_lo
    add addr_lo, n_lo
    adc addr_hi, n_hi
#else
    mov addr_lo, eepr_lo
    add addr_lo, n_lo
#endif

1:  ld  r18, -X
    XCALL   eeprom_update_r18
2:  subi    n_lo, lo8(1)

#if RAMEND > 0xFF  ||  E2END > 0xFF
    sbci    n_hi, hi8(1)
#endif

    brsh    1b
3:  ret

ENDFUNC

#endif  /* E2END && __AVR_ARCH__ > 1 */
#endif  /* !__DOXYGEN__ */