/*
	FreeRTOS.org V5.3.0 - Copyright (C) 2003-2009 Richard Barry.

	This file is part of the FreeRTOS.org distribution.

	FreeRTOS.org is free software; you can redistribute it and/or modify it
	under the terms of the GNU General Public License (version 2) as published
	by the Free Software Foundation and modified by the FreeRTOS exception.
	**NOTE** The exception to the GPL is included to allow you to distribute a
	combined work that includes FreeRTOS.org without being obliged to provide
	the source code for any proprietary components.  Alternative commercial
	license and support terms are also available upon request.  See the 
	licensing section of http://www.FreeRTOS.org for full details.

	FreeRTOS.org 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 FreeRTOS.org; if not, write to the Free Software Foundation, Inc., 59
	Temple Place, Suite 330, Boston, MA  02111-1307  USA.


	***************************************************************************
	*                                                                         *
	* Get the FreeRTOS eBook!  See http://www.FreeRTOS.org/Documentation      *
	*                                                                         *
	* This is a concise, step by step, 'hands on' guide that describes both   *
	* general multitasking concepts and FreeRTOS specifics. It presents and   *
	* explains numerous examples that are written using the FreeRTOS API.     *
	* Full source code for all the examples is provided in an accompanying    *
	* .zip file.                                                              *
	*                                                                         *
	***************************************************************************

	1 tab == 4 spaces!

	Please ensure to read the configuration and relevant port sections of the
	online documentation.

	http://www.FreeRTOS.org - Documentation, latest information, license and
	contact details.

	http://www.SafeRTOS.com - A version that is certified for use in safety
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*/

/* Scheduler include files. */
#include "FreeRTOS.h"
#include "task.h"
#include "queue.h"

/* Constants required for interrupt management. */
#define tcpCLEAR_VIC_INTERRUPT	( 0 )
#define tcpEINT0_VIC_CHANNEL_BIT	( ( unsigned portLONG ) 0x4000 )

/* EINT0 interrupt handler.  This processes interrupts from the WIZnet device. */
void vEINT0_ISR_Wrapper( void ) __attribute__((naked));

/* The handler that goes with the EINT0 wrapper. */
void vEINT0_ISR_Handler( void );

/* Variable is required for its address, but does not otherwise get used. */
static portLONG lDummyVariable;

/*
 * When the WIZnet device asserts an interrupt we send an (empty) message to
 * the TCP task.  This wakes the task so the interrupt can be processed.  The
 * source of the interrupt has to be ascertained by the TCP task as this 
 * requires an I2C transaction which cannot be performed from this ISR.
 * Note this code predates the introduction of semaphores, a semaphore should
 * be used in place of the empty queue message.
 */
void vEINT0_ISR_Handler( void )
{
extern xQueueHandle xTCPISRQueue;
portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;

	/* Just wake the TCP task so it knows an ISR has occurred. */
	xQueueSendFromISR( xTCPISRQueue, ( void * ) &lDummyVariable, &xHigherPriorityTaskWoken );	

	/* We cannot carry on processing interrupts until the TCP task has 
	processed this one - so for now interrupts are disabled.  The TCP task will
	re-enable it. */
	VICIntEnClear |= tcpEINT0_VIC_CHANNEL_BIT;

	/* Clear the interrupt bit. */	
	VICVectAddr = tcpCLEAR_VIC_INTERRUPT;

	if( xHigherPriorityTaskWoken )
	{
		portYIELD_FROM_ISR();
	}
}
/*-----------------------------------------------------------*/

void vEINT0_ISR_Wrapper( void )
{
	/* Save the context of the interrupted task. */
	portSAVE_CONTEXT();

	/* The handler must be a separate function from the wrapper to
	ensure the correct stack frame is set up. */
	vEINT0_ISR_Handler();

	/* Restore the context of whichever task is going to run next. */
	portRESTORE_CONTEXT();
}