/**
 * Copyright (c) 2017 - 2018, Nordic Semiconductor ASA
 * 
 * All rights reserved.
 * 
 * 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, except as embedded into a Nordic
 *    Semiconductor ASA integrated circuit in a product or a software update for
 *    such product, 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 of Nordic Semiconductor ASA nor the names of its
 *    contributors may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 * 
 * 4. This software, with or without modification, must only be used with a
 *    Nordic Semiconductor ASA integrated circuit.
 * 
 * 5. Any software provided in binary form under this license must not be reverse
 *    engineered, decompiled, modified and/or disassembled.
 * 
 * THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS
 * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA 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.
 * 
 */
#include "nrf_bootloader_wdt.h"
#include "nrf_wdt.h"
#include "nrf_bootloader_dfu_timers.h"
#include "nrf_log_ctrl.h"

#define NRF_LOG_MODULE_NAME nrf_bootloader_wdt
#include "nrf_log.h"
NRF_LOG_MODULE_REGISTER();

//Flag used to determine if internal feeding should stay active.
static bool m_wdt_keep_internal_feed;

static void wdt_feed(void)
{
    if (nrf_wdt_started())
    {
        for (nrf_wdt_rr_register_t i = NRF_WDT_RR0; i < NRF_WDT_RR7; i++)
        {
            if (nrf_wdt_reload_request_is_enabled(i))
            {
                nrf_wdt_reload_request_set(i);
            }
        }
    }
}


static void wdt_feed_timer_handler(void)
{
    if (m_wdt_keep_internal_feed)
    {
        NRF_LOG_INFO("Internal feed");
        wdt_feed();
    }
}


void WDT_IRQHandler(void)
{
    nrf_wdt_event_clear(NRF_WDT_EVENT_TIMEOUT);
    NRF_LOG_FINAL_FLUSH();
}

void nrf_bootloader_wdt_init(void)
{
    static bool initialized = false;

    if (initialized)
    {
        return;
    }

    if (nrf_wdt_started())
    {
        uint32_t approx_wdt_ms = nrf_wdt_reload_value_get() / 32;

        NRF_LOG_INFO("WDT enabled CRV:%d ms", approx_wdt_ms);

        //wdt_ticks must be reduced (0.75) to feed the watchdog before the timeout.
        uint32_t reduced_timeout_ms = (approx_wdt_ms * 3)/4;

        /* Ideally, watchdog should be fed by the bootloader from the main context but if bootloader latency
         * (mainly driven by signature check) is big enough there is a risk that watchdog will not be fed
         * on time. In that case watchdog will be fed from timer context. */
        m_wdt_keep_internal_feed =
            (reduced_timeout_ms < NRF_BL_WDT_MAX_SCHEDULER_LATENCY_MS);

        /* initial watchdog feed */
        wdt_feed();

        /* If internal feed is needed or WDT is active in sleep module must provide regular wakeup interrupt.*/
        bool wdt_start_timer = m_wdt_keep_internal_feed || (NRF_WDT->CONFIG & WDT_CONFIG_SLEEP_Msk);
        if (wdt_start_timer)
        {
            NRF_LOG_INFO("Starting a timer (%d ms) for feeding watchdog.", reduced_timeout_ms);
            nrf_bootloader_wdt_feed_timer_start(reduced_timeout_ms, wdt_feed_timer_handler);
        }

        NVIC_EnableIRQ(WDT_IRQn);
    }
    else
    {
        NRF_LOG_INFO("WDT is not enabled");
    }

    initialized = true;
}

void nrf_bootloader_wdt_feed(void)
{
    if (nrf_wdt_started())
    {
        wdt_feed();
    }
}