mpc55xxevb/start/start-watchdog.c

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /**
0004  * @file
0005  *
0006  * @ingroup RTEMSBSPsPowerPCMPC55XX
0007  *
0008  * @brief Watchdog initialization code.
0009  */
0010
0011 /*
0012  * Copyright (c) 2011 embedded brains GmbH & Co. KG
0013  *
0014  * Redistribution and use in source and binary forms, with or without
0015  * modification, are permitted provided that the following conditions
0016  * are met:
0017  * 1. Redistributions of source code must retain the above copyright
0018  *    notice, this list of conditions and the following disclaimer.
0019  * 2. Redistributions in binary form must reproduce the above copyright
0020  *    notice, this list of conditions and the following disclaimer in the
0021  *    documentation and/or other materials provided with the distribution.
0022  *
0023  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
0024  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
0025  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
0026  * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
0027  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
0028  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
0029  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
0030  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
0031  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
0032  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
0033  * POSSIBILITY OF SUCH DAMAGE.
0034  */
0035
0036 #include <bsp.h>
0037 #include <bsp/start.h>
0038 #include <bsp/mpc55xx-config.h>
0039
0040 BSP_START_TEXT_SECTION void mpc55xx_start_watchdog(void)
0041 {
0042   #ifdef MPC55XX_NEEDS_LOW_LEVEL_INIT
0043     #ifdef MPC55XX_HAS_SWT
0044       /* Write keys to clear soft lock bit */
0045       SWT.SR.R = 0x0000c520;
0046       SWT.SR.R = 0x0000d928;
0047
0048       /* Clear watchdog enable (WEN) */
0049       SWT.CR.R = 0x8000010A;
0050     #endif
0051   #endif
0052 }