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//==========================================================================

//

//      watchdog/ebsa285.cxx

//

//      Watchdog implementation for Intel EBSA-285 StronARM board

//

//==========================================================================

//####ECOSGPLCOPYRIGHTBEGIN####

// -------------------------------------------

// This file is part of eCos, the Embedded Configurable Operating System.

// Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.

//

// eCos 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 or (at your option) any later version.

//

// eCos 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 eCos; if not, write to the Free Software Foundation, Inc.,

// 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.

//

// As a special exception, if other files instantiate templates or use macros

// or inline functions from this file, or you compile this file and link it

// with other works to produce a work based on this file, this file does not

// by itself cause the resulting work to be covered by the GNU General Public

// License. However the source code for this file must still be made available

// in accordance with section (3) of the GNU General Public License.

//

// This exception does not invalidate any other reasons why a work based on

// this file might be covered by the GNU General Public License.

//

// Alternative licenses for eCos may be arranged by contacting Red Hat, Inc.

// at http://sources.redhat.com/ecos/ecos-license/

// -------------------------------------------

//####ECOSGPLCOPYRIGHTEND####

//==========================================================================

//#####DESCRIPTIONBEGIN####

//

// Author(s):    jskov (based on the MN10300 watchdog code by nickg)

// Contributors: jskov, nickg

// Date:         1999-08-26

// Purpose:      Watchdog class implementation

// Description:  Contains an implementation of the Watchdog class for use

//               with the EBSA285/21285 hardware watchdog timer.

//

//####DESCRIPTIONEND####

//

//==========================================================================

#include <pkgconf/system.h>             // system configuration file

#include <pkgconf/watchdog.h>           // configuration for this package

#include <pkgconf/kernel.h>             // kernel config

#include <cyg/infra/cyg_trac.h>         // tracing macros

#include <cyg/kernel/instrmnt.h>        // instrumentation

#include <cyg/hal/hal_io.h>             // IO register access

#include <cyg/io/watchdog.hxx>          // watchdog API

// -------------------------------------------------------------------------

// 21285 watchdog works by letting timer4 run; if it ever underflows,

// it resets the system. 

// Timer 4 is set to run at fclk_in/16 = 50MHz/16 = 3.125MHz

// The timer register is 24 bits, so it can easily hold a value that

// gives a 1s timeout.

#define WATCHDOG_TIMER_TICKS            3125000

#define WATCHDOG_RESOLUTION             (1000000000)

// -------------------------------------------------------------------------

// Constructor

void

Cyg_Watchdog::init_hw(void)

{

    CYG_REPORT_FUNCTION();

    // HW doesn't need init

    resolution          = WATCHDOG_RESOLUTION;

    CYG_REPORT_RETURN();

}

// -------------------------------------------------------------------------

// Start the watchdog running.

void

Cyg_Watchdog::start(void)

{

    CYG_REPORT_FUNCTION();

    // Init the watchdog timer.

    HAL_WRITE_UINT32(SA110_TIMER4_LOAD, WATCHDOG_TIMER_TICKS);

    HAL_WRITE_UINT32(SA110_TIMER4_CLEAR, 0);

    HAL_WRITE_UINT32(SA110_TIMER4_CONTROL,

                     SA110_TIMER_CONTROL_ENABLE|SA110_TIMER_CONTROL_SCALE_16);

    // Enable the watchdog.

    cyg_uint32 ctrl;

    HAL_READ_UINT32(SA110_CONTROL, ctrl);

    ctrl |= SA110_CONTROL_WATCHDOG;

    HAL_WRITE_UINT32(SA110_CONTROL, ctrl);

    CYG_REPORT_RETURN();

}

// -------------------------------------------------------------------------

// Reset watchdog timer. This needs to be called regularly to prevent

// the watchdog firing.

void

Cyg_Watchdog::reset()

{

    CYG_REPORT_FUNCTION();

    HAL_WRITE_UINT32(SA110_TIMER4_LOAD, WATCHDOG_TIMER_TICKS);

    CYG_REPORT_RETURN();

}

#if 0

// -------------------------------------------------------------------------

// Trigger the watchdog as if the timer had expired.

void

Cyg_Watchdog::reset_action(void)

{

    CYG_REPORT_FUNCTION();

    // Init the watchdog timer.

    HAL_WRITE_UINT32(SA110_TIMER4_LOAD, 1);

    HAL_WRITE_UINT32(SA110_TIMER4_CONTROL, SA110_TIMER_CONTROL_ENABLE);

    // Enable the watchdog.

    cyg_uint32 ctrl;

    HAL_READ_UINT32(SA110_CONTROL, ctrl);

    ctrl |= SA110_CONTROL_WATCHDOG;

    HAL_WRITE_UINT32(SA110_CONTROL, ctrl);

    CYG_REPORT_RETURN();

}

#endif

// -------------------------------------------------------------------------

// EOF watchdog_ebsa285.cxx