/*
 * Copyright (c) 2012, Natie van Rooyen. 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 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. No personal names or organizations' names associated with the
 *    Atomthreads project may be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE ATOMTHREADS PROJECT 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 PROJECT 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 "modules.h"
#include <stdio.h>
#include <stdarg.h>
#include "atomport_private.h"
#include "atom.h"
#include "atomport.h"
#include "types.h"

ICP_TIMER_T*                   const           board_timer_0           = (ICP_TIMER_T*)               BOARD_BASE_ADDRESS_TIMER_0 ;
ICP_PIC_T  *                   const           board_pic               = (ICP_PIC_T*)                 BOARD_BASE_ADDRESS_PIC ;

/**
 * \b dbg_format_msg
 *
 * Same as printf. 
 *
 */
void 
dbg_format_msg (char *format, ...)
{
	va_list			args;
	static char		msg[256] ;
    CRITICAL_STORE ;

    va_start (args, format) ;
    CRITICAL_START() ;
	vsnprintf ((char*)msg, 256, (char*)format, args) ;
    CRITICAL_END() ;

    printf (msg) ;
}

/**
 * \b low_level_init
 *
 * Initializes the PIC and start the system timer tick intrerupt.
 *
 */
int
low_level_init (void)
{

    board_pic->IRQ_ENABLECLR = ICP_PIC_IRQ_TIMERINT0 ;
    board_timer_0->INTCLR = 1 ;
    board_pic->IRQ_ENABLESET |= ICP_PIC_IRQ_TIMERINT0 ;

    board_timer_0->LOAD = 0x2000 ;
    board_timer_0->BGLOAD = 0x2000 ;
    board_timer_0->CONTROL = ICP_TIMER_CONTROL_ENABLE |
                            ICP_TIMER_CONTROL_MODE |
                            ICP_TIMER_CONTROL_IE |
                            /*ICP_TIMER_CONTROL_PRESCALE_256 |*/
                            ICP_TIMER_CONTROL_TIMER_SIZE ;

    return 0 ;
}


/**
 * \b __context_preempt_handler
 *
 * System timer tic interupt handler.
 *
 */
void
__context_preempt_handler (void) 
{
    unsigned int status = board_pic->IRQ_STATUS ;

    if (status | ICP_PIC_IRQ_TIMERINT0) {
        
        atomIntEnter();

        /* Call the OS system tick handler */
        atomTimerTick();

        /* ack the interrupt */
        board_timer_0->INTCLR = 0x1 ;

        /* Call the interrupt exit routine */
        atomIntExit(TRUE);

    }


}