/****************************************************************************
 * arch/arm/src/armv6-m/up_systemreset.c
 *
 *   Copyright (C) 2013 Gregory Nutt. All rights reserved.
 *   Author: Gregory Nutt <gnutt@nuttx.org>
 *           Darcy Gong
 *
 * 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. Neither the name NuttX 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 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.
 *
 ****************************************************************************/

/****************************************************************************
 * Included Files
 ****************************************************************************/

#include <nuttx/config.h>

#include <stdint.h>

#include <nuttx/board.h>

#include "up_arch.h"
#include "nvic.h"

/****************************************************************************
 * Public functions
 ****************************************************************************/

/****************************************************************************
 * Name: up_systemreset
 *
 * Description:
 *   Internal, Cortex-M0 reset logic.
 *
 ****************************************************************************/

void up_systemreset(void)
{
  uint32_t regval;

  /* Set up for the system reset, retaining the priority group from the
   * the AIRCR register.
   */

  regval = ((0x5fa << SYSCON_AIRCR_VECTKEY_SHIFT) | SYSCON_AIRCR_SYSRESETREQ);
  putreg32(regval, ARMV6M_SYSCON_AIRCR);

  /* Ensure completion of memory accesses */

  __asm volatile ("dsb");

  /* Wait for the reset */

  for (; ; );
}


/****************************************************************************
 * Name: board_reset
 *
 * Description:
 *   Reset board.  This function may or may not be supported by a
 *   particular board architecture.
 *
 * Input Parameters:
 *   status - Status information provided with the reset event.  This
 *     meaning of this status information is board-specific.  If not used by
 *     a board, the value zero may be provided in calls to board_reset.
 *
 * Returned Value:
 *   If this function returns, then it was not possible to power-off the
 *   board due to some constraints.  The return value int this case is a
 *   board-specific reason for the failure to shutdown.
 *
 ****************************************************************************/

#ifdef CONFIG_BOARDCTL_RESET
int board_reset(int status)
{
  up_systemreset();
  return 0;
}
#endif

