/*
 * File      : board_timer.c
 * This file is part of RT-Thread RTOS
 * COPYRIGHT (C) 2008 - 2016, RT-Thread Development Team
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License along
 *  with this program; if not, write to the Free Software Foundation, Inc.,
 *  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Change Logs:
 * Date           Author       Notes
 * 2015-11-19     Urey         the first version
 */

#include <rthw.h>
#include <rtthread.h>
#include <rtdevice.h>

#include <stdint.h>

#include "board.h"
#include "drv_clock.h"
#include "drv_ost.h"

/**
 * This is the OST timer interrupt service routine.
 */
void rt_hw_ost_handler(void)
{
    /* increase a OS tick */
    rt_tick_increase();

    /* clear flag */
    REG_OSTFR = 0;
}

void rt_hw_ost_init(void)
{
    rt_uint32_t cnt, div;
    struct clk  *clk;

    div = OST_DIV16;
    cnt = BOARD_EXTAL_CLK / 16;

    /* enable OST clock */
    clk = clk_get("sys_ost");
    clk_enable(clk);

    /* Disable OST (channel 1/2) */
    REG_OSTECR = 0x3;

    /* clear counter */
    REG_OSTCR = 0x01;
    REG_OST1CNT = 0;

    /* set timer data (channel 1) */
    REG_OST1DFR   = (cnt / RT_TICK_PER_SECOND - 1);

    /* set prescale ext clk */
    REG_OSTCCR = div;

    /* unmask interrupt */
    REG_OSTMR = 0;

    /* enable OST (channel 1) */
    REG_OSTESR = 0x01;

    clk_put(clk);
}