Subversion Repositories amber

/*----------------------------------------------------------------

//                                                              //

//  boot-loader-ethmac.c                                        //

//                                                              //

//  This file is part of the Amber project                      //

//  http://www.opencores.org/project,amber                      //

//                                                              //

//  Description                                                 //

//  The main functions for the boot loader application. This    //

//  application is embedded in the FPGA's SRAM and is used      //

//  to load larger applications into the DDR3 memory on         //

//  the development board.                                      //

//                                                              //

//  Author(s):                                                  //

//      - Conor Santifort, csantifort.amber@gmail.com           //

//                                                              //

//////////////////////////////////////////////////////////////////

//                                                              //

// Copyright (C) 2011 Authors and OPENCORES.ORG                 //

//                                                              //

// This source file may be used and distributed without         //

// restriction provided that this copyright statement is not    //

// removed from the file and that any derivative work contains  //

// the original copyright notice and the associated disclaimer. //

//                                                              //

// This source file is free software; you can redistribute it   //

// and/or modify it under the terms of the GNU Lesser General   //

// Public License as published by the Free Software Foundation; //

// either version 2.1 of the License, or (at your option) any   //

// later version.                                               //

//                                                              //

// This source 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 Lesser General Public License for more //

// details.                                                     //

//                                                              //

// You should have received a copy of the GNU Lesser General    //

// Public License along with this source; if not, download it   //

// from http://www.opencores.org/lgpl.shtml                     //

//                                                              //

----------------------------------------------------------------*/

#include "amber_registers.h"

#include "utilities.h"

#include "timer.h"

/* Global variable for the current time */

time_t* current_time_g;

/* Create a timer object */

time_t* new_timer()

{

    time_t* timer;

    timer= malloc(sizeof(time_t));

    timer->milliseconds = 0;

    timer->seconds      = 0;

    return timer;

}

/*Initialize a global variable that keeps

  track of the current up time. Timers are

  compared against this running value.

*/

void init_timer()

{

    /* Initialize the current time object */

    current_time_g = new_timer();

    /* Configure timer 0 */

    /* Counts down from this value and generates an interrupt every 1/100 seconds */

    *(unsigned int *) ( ADR_AMBER_TM_TIMER0_LOAD ) = 1562; // 16-bit, x 256

    *(unsigned int *) ( ADR_AMBER_TM_TIMER0_CTRL ) = 0xc8;  // enable[7], periodic[6],

    /* Enable timer 0 interrupt */

    *(unsigned int *) ( ADR_AMBER_IC_IRQ0_ENABLESET ) = 0x020;

}

/* Set the timer to current time plus a number of milliseconds */

void set_timer (time_t* timer, int milliseconds)

{

    int seconds = _div(milliseconds, 1000);

    int mseconds = milliseconds - seconds*1000;  /* milliseconds % 1000  */

    if (current_time_g->milliseconds >= (1000 - mseconds)) {

        timer->seconds      = current_time_g->seconds + 1;

        timer->milliseconds = current_time_g->milliseconds + mseconds - 1000;

        }

    else {

        timer->seconds      = current_time_g->seconds;

        timer->milliseconds = current_time_g->milliseconds + mseconds;

        }

   timer->seconds += seconds;

}

void timer_interrupt()

{

    /* Clear timer 0 interrupt in timer */

    *(unsigned int *) ( ADR_AMBER_TM_TIMER0_CLR ) = 1;

    /* Disable timer 0 interrupt in interrupt controller */

    *(unsigned int *) ( ADR_AMBER_IC_IRQ0_ENABLECLR ) = 0x020;

    /* Update the global current_time variable */

    if (current_time_g->milliseconds == 990) {

        current_time_g->milliseconds = 0;

        current_time_g->seconds++;

        }

    else {

        current_time_g->milliseconds+=10;

        }

    /* Enable timer 0 interrupt in interrupt controller */

    *(unsigned int *) ( ADR_AMBER_IC_IRQ0_ENABLESET ) = 0x020;

}

/* Return true if timer has expired */

int timer_expired(time_t * expiry_time)

{

    if (!expiry_time->seconds && !expiry_time->milliseconds)

        /* timer is not set */

        return 0;

    else if (expiry_time->seconds < current_time_g->seconds)

        return 1;

    else if ((expiry_time->seconds      == current_time_g->seconds) &&

             (expiry_time->milliseconds < current_time_g->milliseconds))

        return 1;

    else

        return 0;

}