raspberrypi/start/watchdog.c

0001 /* SPDX-License-Identifier: BSD-2-Clause */
0002
0003 /**
0004  * @file
0005  *
0006  * @ingroup RTEMSBSPsAArch64RaspberryPi
0007  *
0008  * @brief Watchdog Driver
0009  */
0010
0011 /*
0012  * Copyright (C) 2024 Ning Yang
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/raspberrypi.h>
0037 #include <bsp/watchdog.h>
0038
0039 #define PM_WDOG BCM2835_REG(BCM2711_PM_WDOG)
0040 #define PM_RSTC BCM2835_REG(BCM2711_PM_RSTC)
0041
0042 uint32_t raspberrypi_watchdog_timeout;
0043
0044 void raspberrypi_watchdog_init()
0045 {
0046   raspberrypi_watchdog_timeout = 0;
0047 }
0048
0049 void raspberrypi_watchdog_start(uint32_t timeout_ms)
0050 {
0051   raspberrypi_watchdog_timeout = timeout_ms;
0052
0053   PM_WDOG = BCM2711_PM_PASSWD_MAGIC |
0054             ((timeout_ms * 65536 / 1000) & BCM2711_PM_WDOG_MASK);
0055
0056   PM_RSTC &= BCM2711_PM_RSTC_WRCFG_CLR;
0057   PM_RSTC = (BCM2711_PM_PASSWD_MAGIC | BCM2711_PM_RSTC_WRCFG_FULL);
0058 }
0059
0060 void raspberrypi_watchdog_stop()
0061 {
0062   PM_RSTC = BCM2711_PM_PASSWD_MAGIC | BCM2711_PM_RSTC_RESET;
0063 }
0064
0065 void raspberrypi_watchdog_reload()
0066 {
0067   raspberrypi_watchdog_start(raspberrypi_watchdog_timeout);
0068 }
0069
0070 uint32_t raspberrypi_watchdog_get_remaining_time()
0071 {
0072   return (PM_WDOG & BCM2711_PM_WDOG_MASK)*1000/65536;
0073 }