infomem.c

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/*
Copyright 2007, Freie Universitaet Berlin. All rights reserved.

These sources were developed at the Freie Universit鋞 Berlin, Computer
Systems and Telematics group.

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- Redistributions in binary form must reproduce the above copyright
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documentation and/or other materials provided with the distribution.
 
- Neither the name of Freie Universitaet Berlin (FUB) nor the names of its
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.

This software is provided by FUB and the contributors on an "as is"
basis, without any representations or warranties of any kind, express
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particular purpose. In no event shall FUB or contributors be liable
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This implementation was developed by the CST group at the FUB.

For documentation and questions please use the web site
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Berlin, 2007
*/

/**
 * @file		infomem.c
 * @addtogroup	storage
 * @brief		MSP430 Infomemory Storage
 * @author		Michael Baar	<[e-mail]>
 *
 * Functions to store and read data from the two infomemories (2 x 128 Bytes).
 * Offset addresses start at zero, size has a maximum of 128, write operations
 * across both blocks are not allowed.
 */
#include <string.h>
#include <signal.h>
#include <stdarg.h>
#include "contiki-conf.h"
#include <msp430/flash.h>
#include "infomem.h"

void
infomem_read(void *buffer, unsigned int offset, unsigned char size)
{
  uint8_t *address = (uint8_t *) INFOMEM_START + offset;
  memcpy(buffer, address, size);
}

bool
infomem_write(unsigned int offset, unsigned char count, ...)
{
  char backup[INFOMEM_BLOCK_SIZE];	
  uint8_t *buffer;
  uint16_t i;
  uint8_t *flash;
  va_list argp;
  uint16_t size;
  uint8_t *data;
  int s;

  if (offset > (2 * INFOMEM_BLOCK_SIZE))
    return FALSE;

  flash = (uint8_t *) INFOMEM_START + offset;

  s = splhigh();

  // backup into RAM
  memcpy(backup, flash, INFOMEM_BLOCK_SIZE);

  // merge backup with new data
  va_start(argp, count);

  buffer = (uint8_t *) backup;
  for (i = 0; i < count; i++) {
    data = va_arg(argp, uint8_t*);
    size = va_arg(argp, uint16_t);
    memcpy(buffer, data, size);
    buffer += size;
  }

  va_end(argp);

  // init flash access
  FCTL2 = FWKEY + FSSEL1 + FN2;
  FCTL3 = FWKEY;

  // erase flash
  FCTL1 = FWKEY + ERASE;
  *flash = 0;

  // write flash
  FCTL1 = FWKEY + WRT;
  buffer = (uint8_t *) backup;
  for (i = 0; i < INFOMEM_BLOCK_SIZE; i++) {
    *flash++ = *buffer++;
  }

  FCTL1 = FWKEY;
  FCTL3 = FWKEY + LOCK;

  splx(s);

  return TRUE;
}