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/*
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"
__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();
if( xTaskIncrementTick() != pdFALSE )
{
taskYIELD();
}
portCLEAR_INTERRUPT_MASK_FROM_ISR( ulSavedInterruptMask );
}
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