//==========================================================================
//
//      io/watchdog/watchdog.cxx
//
//      Watchdog common code
//
//==========================================================================
// ####ECOSGPLCOPYRIGHTBEGIN####                                            
// -------------------------------------------                              
// This file is part of eCos, the Embedded Configurable Operating System.   
// Copyright (C) 1998, 1999, 2000, 2001, 2002, 2009 Free Software Foundation, Inc.
// Copyright (C) 2004 eCosCentric Limited                                   
//
// 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.                                                                 
//
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// 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.,    
// 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, 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   
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// must still be made available in accordance with section (3) of the GNU   
// General Public License v2.                                               
//
// This exception does not invalidate any other reasons why a work based    
// on this file might be covered by the GNU General Public License.         
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// ####ECOSGPLCOPYRIGHTEND####                                              
//==========================================================================
//#####DESCRIPTIONBEGIN####
//
// Author(s):    nickg
// Contributors: nickg
// Date:         1999-02-18
// Purpose:      Watchdog class implementation
//
//####DESCRIPTIONEND####
//
//==========================================================================

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

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

#include <cyg/hal/drv_api.h>            // for locking

#include <cyg/io/watchdog.hxx>          // watchdog API
#include <cyg/io/watchdog.h>            // watchdog c-api

// -------------------------------------------------------------------------
// Statics

// A static pointer to the single system defined watchdog device.
Cyg_Watchdog Cyg_Watchdog::watchdog CYGBLD_ATTRIB_INIT_PRI( CYG_INIT_DEV_WATCHDOG );

// -------------------------------------------------------------------------
// Constructor


Cyg_Watchdog::Cyg_Watchdog()
{
    CYG_REPORT_FUNCTION();

#ifndef CYGSEM_WATCHDOG_RESETS_ON_TIMEOUT    
    action_list         = 0;
#endif

    // HW driver initialization. This must set the watchdog resolution.
    init_hw();
        
    CYG_REPORT_RETURN();
}

// -------------------------------------------------------------------------
// Return reset resolution

cyg_uint64
Cyg_Watchdog::get_resolution()
{
    return resolution;
}

#ifndef CYGSEM_WATCHDOG_RESETS_ON_TIMEOUT
// -------------------------------------------------------------------------
// Trigger the watchdog as if the timer had expired. This should be called
// from the driver's ISR.

void
Cyg_Watchdog::trigger()
{
    CYG_REPORT_FUNCTION();
    
    cyg_drv_dsr_lock();
    
    Cyg_Watchdog_Action *act = action_list;

    while( 0 != act )
    {
        act->action( act->data );

        act = act->next;
    }

    cyg_drv_dsr_unlock();

    CYG_REPORT_RETURN();
}
    
// -------------------------------------------------------------------------
// Register an action routine that will be called when the timer
// triggers.

void
Cyg_Watchdog::install_action( Cyg_Watchdog_Action *action )
{
    CYG_REPORT_FUNCTION();
    
    cyg_drv_dsr_lock();
    
    action->next = action_list;
    action_list = action;

    cyg_drv_dsr_unlock();

    CYG_REPORT_RETURN();
}

// -------------------------------------------------------------------------
// Deregister a previously registered action routine.

void
Cyg_Watchdog::uninstall_action( Cyg_Watchdog_Action *action )
{
    CYG_REPORT_FUNCTION();
    
    cyg_drv_dsr_lock();

    Cyg_Watchdog_Action **act_ptr = &action_list;    

    while( 0 != *act_ptr )
    {
        Cyg_Watchdog_Action *a = *act_ptr;

        if( a == action )
        {
            *act_ptr = a->next;
            break;
        }
        act_ptr = &a->next;
    }
    
    cyg_drv_dsr_unlock();

    CYG_REPORT_RETURN();
}

#endif // CYGSEM_WATCHDOG_RESETS_ON_TIMEOUT

// -------------------------------------------------------------------------
// Implementation of the C-api

externC void
watchdog_start(void)
{
  Cyg_Watchdog::watchdog.start();
}

externC void
watchdog_reset(void)
{
  Cyg_Watchdog::watchdog.reset();
}

externC cyg_uint64
watchdog_get_resolution(void)
{
  return Cyg_Watchdog::watchdog.get_resolution();
}

// -------------------------------------------------------------------------
// EOF io/watchdog/watchdog.cxx
