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/*

    FreeRTOS V6.1.1 - Copyright (C) 2011 Real Time Engineers Ltd.

    ***************************************************************************

    *                                                                         *

    * If you are:                                                             *

    *                                                                         *

    *    + New to FreeRTOS,                                                   *

    *    + Wanting to learn FreeRTOS or multitasking in general quickly       *

    *    + Looking for basic training,                                        *

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    *                                                                         *

    * then take a look at the FreeRTOS books - available as PDF or paperback  *

    *                                                                         *

    *        "Using the FreeRTOS Real Time Kernel - a Practical Guide"        *

    *                  http://www.FreeRTOS.org/Documentation                  *

    *                                                                         *

    * A pdf reference manual is also available.  Both are usually delivered   *

    * to your inbox within 20 minutes to two hours when purchased between 8am *

    * and 8pm GMT (although please allow up to 24 hours in case of            *

    * exceptional circumstances).  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 exception 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 it

    can be viewed here: http://www.freertos.org/a00114.html and also obtained

    by writing to Richard Barry, contact details for whom are available on the

    FreeRTOS WEB site.

    1 tab == 4 spaces!

    http://www.FreeRTOS.org - Documentation, latest information, license and

    contact details.

    http://www.SafeRTOS.com - A version that is certified for use in safety

    critical systems.

    http://www.OpenRTOS.com - Commercial support, development, porting,

    licensing and training services.

*/

#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.  The name of the

 *  handler function (currently vPIT0InterruptHandler()) should also be updated

 *  to indicate which peripheral is generating the interrupt.

 *

 *      2) Make sure the interrupt source is cleared within the interrupt handler function.

 *  Currently vPIT0InterruptHandler() clears the PIT0 interrupt.

 *

 *  3) Update the vector table within mcf5225x_vectors.s to install the tick

 *  interrupt handler in the correct vector position.

 *

 * 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) Update the vector table within mcf5225x_vectors.s to install the handler

 *  _vPortYieldISR() in the correct vector position (by default vector number 16 is

 *  used).

 */

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

}