text: /****************************************************************************
   * arch/arm/src/armv6-m/up_systemreset.c
   *
   *   Copyright (C) 2013, 2019 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/arch.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 (; ; );
  }
  