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/*
    FreeRTOS V7.4.0 - Copyright (C) 2013 Real Time Engineers Ltd.

    FEATURES AND PORTS ARE ADDED TO FREERTOS ALL THE TIME.  PLEASE VISIT
    http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.

    ***************************************************************************
     *                                                                       *
     *    FreeRTOS tutorial books are available in pdf and paperback.        *
     *    Complete, revised, and edited pdf reference manuals are also       *
     *    available.                                                         *
     *                                                                       *
     *    Purchasing FreeRTOS documentation will not only help you, by       *
     *    ensuring you get running as quickly as possible and with an        *
     *    in-depth knowledge of how to use FreeRTOS, it will also help       *
     *    the FreeRTOS project to continue with its mission of providing     *
     *    professional grade, cross platform, de facto standard solutions    *
     *    for microcontrollers - completely free of charge!                  *
     *                                                                       *
     *    >>> See http://www.FreeRTOS.org/Documentation for details. <<<     *
     *                                                                       *
     *    Thank you for using FreeRTOS, and thank you for your support!      *
     *                                                                       *
    ***************************************************************************


    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.  See the GNU General Public License for more
    details. You should have received a copy of the GNU General Public License
    and the FreeRTOS license exception along with FreeRTOS; if not itcan be
    viewed here: http://www.freertos.org/a00114.html and also obtained by
    writing to Real Time Engineers Ltd., contact details for whom are available
    on the FreeRTOS WEB site.

    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, and our new
    fully thread aware and reentrant UDP/IP stack.

    http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High 
    Integrity Systems, who sell the code with commercial support, 
    indemnification and middleware, under the OpenRTOS brand.
    
    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.
*/

#include "FreeRTOS.h"
#include "task.h"

__declspec(interrupt:0) void vPIT0InterruptHandler( void );

/* Constants used to configure the interrupts. */
#define portPRESCALE_VALUE			64
#define portPRESCALE_REG_SETTING	( 5 << 8 )
#define portPIT_INTERRUPT_ENABLED	( 0x08 )
#define configPIT0_INTERRUPT_VECTOR	( 55 )

/*
 * FreeRTOS.org requires two interrupts - a tick interrupt generated from a
 * timer source, and a spare interrupt vector used for context switching.
 * The configuration below uses PIT0 for the former, and vector 16 for the
 * latter.  **IF YOUR APPLICATION HAS BOTH OF THESE INTERRUPTS FREE THEN YOU DO
 * NOT NEED TO CHANGE ANY OF THIS CODE** - otherwise instructions are provided
 * here for using alternative interrupt sources.
 *
 * To change the tick interrupt source:
 *
 *	1) Modify vApplicationSetupInterrupts() below to be correct for whichever
 *	peripheral is to be used to generate the tick interrupt.
 *
 *	2) Change the name of the function __cs3_isr_interrupt_119() defined within
 *	this file to be correct for the interrupt vector used by the timer peripheral.
 *	The name of the function should contain the vector number, so by default vector
 *	number 119 is being used.
 *
 *	3) Make sure the tick interrupt is cleared within the interrupt handler function.
 *  Currently __cs3_isr_interrupt_119() clears the PIT0 interrupt.
 *
 * To change the spare interrupt source:
 *
 *  1) Modify vApplicationSetupInterrupts() below to be correct for whichever
 *  interrupt vector is to be used.  Make sure you use a spare interrupt on interrupt
 *  controller 0, otherwise the register used to request context switches will also
 *  require modification.
 *
 *  2) Change the definition of configYIELD_INTERRUPT_VECTOR within FreeRTOSConfig.h
 *  to be correct for your chosen interrupt vector.
 *
 *  3) Change the name of the function __cs3_isr_interrupt_127() within portasm.S
 *  to be correct for whichever vector number is being used.  By default interrupt
 *  controller 0 number 16 is used, which corresponds to vector number 127.
 */
void vApplicationSetupInterrupts( void )
{
const unsigned portSHORT usCompareMatchValue = ( ( configCPU_CLOCK_HZ / portPRESCALE_VALUE ) / configTICK_RATE_HZ );

    /* Configure interrupt priority and level and unmask interrupt for PIT0. */
    MCF_INTC0_ICR55 = ( 1 | ( configKERNEL_INTERRUPT_PRIORITY << 3 ) );
    MCF_INTC0_IMRH &= ~( MCF_INTC_IMRH_INT_MASK55 );

    /* Do the same for vector 63 (interrupt controller 0.  I don't think the
    write to MCF_INTC0_IMRH is actually required here but is included for
    completeness. */
    MCF_INTC0_ICR16 = ( 0 | configKERNEL_INTERRUPT_PRIORITY << 3 );
    MCF_INTC0_IMRL &= ~( MCF_INTC_IMRL_INT_MASK16 | 0x01 );

    /* Configure PIT0 to generate the RTOS tick. */
    MCF_PIT0_PCSR |= MCF_PIT_PCSR_PIF;
    MCF_PIT0_PCSR = ( portPRESCALE_REG_SETTING | MCF_PIT_PCSR_PIE | MCF_PIT_PCSR_RLD | MCF_PIT_PCSR_EN );
	MCF_PIT0_PMR = usCompareMatchValue;
}
/*-----------------------------------------------------------*/

__declspec(interrupt:0) void vPIT0InterruptHandler( void )
{
unsigned portLONG ulSavedInterruptMask;

	/* Clear the PIT0 interrupt. */
	MCF_PIT0_PCSR |= MCF_PIT_PCSR_PIF;

	/* Increment the RTOS tick. */
	ulSavedInterruptMask = portSET_INTERRUPT_MASK_FROM_ISR();
		vTaskIncrementTick();
	portCLEAR_INTERRUPT_MASK_FROM_ISR( ulSavedInterruptMask );

	/* If we are using the pre-emptive scheduler then also request a
	context switch as incrementing the tick could have unblocked a task. */
	#if configUSE_PREEMPTION == 1
	{
		taskYIELD();
	}
	#endif
}