/*
    FreeRTOS V9.0.0 - Copyright (C) 2016 Real Time Engineers Ltd.
    All rights reserved

    VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.

    This file is part of the FreeRTOS distribution.

    FreeRTOS 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 modification to the GPL is included to allow you to     !<<
    >>!   distribute a combined work that includes FreeRTOS without being   !<<
    >>!   obliged to provide the source code for proprietary components     !<<
    >>!   outside of the FreeRTOS kernel.                                   !<<
    ***************************************************************************

    FreeRTOS 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.  Full license text is available on the following
    link: http://www.freertos.org/a00114.html

    ***************************************************************************
     *                                                                       *
     *    FreeRTOS provides completely free yet professionally developed,    *
     *    robust, strictly quality controlled, supported, and cross          *
     *    platform software that is more than just the market leader, it     *
     *    is the industry's de facto standard.                               *
     *                                                                       *
     *    Help yourself get started quickly while simultaneously helping     *
     *    to support the FreeRTOS project by purchasing a FreeRTOS           *
     *    tutorial book, reference manual, or both:                          *
     *    http://www.FreeRTOS.org/Documentation                              *
     *                                                                       *
    ***************************************************************************

    http://www.FreeRTOS.org/FAQHelp.html - Having a problem?  Start by reading
    the FAQ page "My application does not run, what could be wrong?".  Have you
    defined configASSERT()?

    http://www.FreeRTOS.org/support - In return for receiving this top quality
    embedded software for free we request you assist our global community by
    participating in the support forum.

    http://www.FreeRTOS.org/training - Investing in training allows your team to
    be as productive as possible as early as possible.  Now you can receive
    FreeRTOS training directly from Richard Barry, CEO of Real Time Engineers
    Ltd, and the world's leading authority on the world's leading RTOS.

    http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
    including FreeRTOS+Trace - an indispensable productivity tool, a DOS
    compatible FAT file system, and our tiny thread aware UDP/IP stack.

    http://www.FreeRTOS.org/labs - Where new FreeRTOS products go to incubate.
    Come and try FreeRTOS+TCP, our new open source TCP/IP stack for FreeRTOS.

    http://www.OpenRTOS.com - Real Time Engineers ltd. license FreeRTOS to High
    Integrity Systems ltd. to sell under the OpenRTOS brand.  Low cost OpenRTOS
    licenses offer ticketed support, indemnification and commercial middleware.

    http://www.SafeRTOS.com - High Integrity Systems also provide a safety
    engineered and independently SIL3 certified version for use in safety and
    mission critical applications that require provable dependability.

    1 tab == 4 spaces!
*/

/* 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 long ) 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 long 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 QueueHandle_t 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();
}