/*
    FreeRTOS V7.5.3 - Copyright (C) 2013 Real Time Engineers Ltd. 
    All rights reserved

    VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.

    ***************************************************************************
     *                                                                       *
     *    FreeRTOS provides completely free yet professionally developed,    *
     *    robust, strictly quality controlled, supported, and cross          *
     *    platform software that has become a de facto standard.             *
     *                                                                       *
     *    Help yourself get started quickly and support the FreeRTOS         *
     *    project by purchasing a FreeRTOS tutorial book, reference          *
     *    manual, or both from: http://www.FreeRTOS.org/Documentation        *
     *                                                                       *
     *    Thank you!                                                         *
     *                                                                       *
    ***************************************************************************

    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 from the following
    link: http://www.freertos.org/a00114.html

    1 tab == 4 spaces!

    ***************************************************************************
     *                                                                       *
     *    Having a problem?  Start by reading the FAQ "My application does   *
     *    not run, what could be wrong?"                                     *
     *                                                                       *
     *    http://www.FreeRTOS.org/FAQHelp.html                               *
     *                                                                       *
    ***************************************************************************

    http://www.FreeRTOS.org - Documentation, books, training, latest versions,
    license and Real Time Engineers Ltd. contact details.

    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.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High
    Integrity Systems to sell under the OpenRTOS brand.  Low cost OpenRTOS
    licenses offer ticketed support, indemnification and 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!
*/


#include "FreeRTOS.h"
#include "task.h"
#include "semphr.h"
#include "SAM7_EMAC.h"
#include "AT91SAM7X256.h"

/*-----------------------------------------------------------*/

/* The semaphore used to signal the arrival of new data to the interface
task. */
static xSemaphoreHandle xSemaphore = NULL;

/* The interrupt entry point is naked so we can control the context saving. */
void vEMACISR_Wrapper( void ) __attribute__((naked));

/* The interrupt handler function must be separate from the entry function
to ensure the correct stack frame is set up. */
void vEMACISR_Handler( void );

/*-----------------------------------------------------------*/
/*
 * The EMAC ISR.  Handles both Tx and Rx complete interrupts.
 */
void vEMACISR_Handler( void )
{
volatile unsigned long ulIntStatus, ulEventStatus;
portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;
extern void vClearEMACTxBuffer( void );

	/* Find the cause of the interrupt. */
	ulIntStatus = AT91C_BASE_EMAC->EMAC_ISR;
	ulEventStatus = AT91C_BASE_EMAC->EMAC_RSR;

	if( ( ulIntStatus & AT91C_EMAC_RCOMP ) || ( ulEventStatus & AT91C_EMAC_REC ) )
	{
		/* A frame has been received, signal the lwIP task so it can process
		the Rx descriptors. */
		xSemaphoreGiveFromISR( xSemaphore, &xHigherPriorityTaskWoken );
		AT91C_BASE_EMAC->EMAC_RSR = AT91C_EMAC_REC;
	}

	if( ulIntStatus & AT91C_EMAC_TCOMP )
	{
		/* A frame has been transmitted.  Mark all the buffers used by the
		frame just transmitted as free again. */
		vClearEMACTxBuffer();
		AT91C_BASE_EMAC->EMAC_TSR = AT91C_EMAC_COMP;
	}

	/* Clear the interrupt. */
	AT91C_BASE_AIC->AIC_EOICR = 0;

	/* If a task was woken by either a frame being received then we may need to 
	switch to another task.  If the unblocked task was of higher priority then
	the interrupted task it will then execute immediately that the ISR
	completes. */
	if( xHigherPriorityTaskWoken )
	{
		portYIELD_FROM_ISR();
	}
}
/*-----------------------------------------------------------*/

void  vEMACISR_Wrapper( void )
{
	/* Save the context of the interrupted task. */
	portSAVE_CONTEXT();

	/* Call the handler to do the work.  This must be a separate
	function to ensure the stack frame is set up correctly. */
	vEMACISR_Handler();

	/* Restore the context of whichever task will execute next. */
	portRESTORE_CONTEXT();
}
/*-----------------------------------------------------------*/

void vPassEMACSemaphore( xSemaphoreHandle xCreatedSemaphore )
{
	/* Simply store the semaphore that should be used by the ISR. */
	xSemaphore = xCreatedSemaphore;
}