/* | |
FreeRTOS V5.4.2 - Copyright (C) 2009 Real Time Engineers Ltd. | |
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. | |
Alternative commercial license and support terms are also available upon | |
request. See the licensing section of http://www.FreeRTOS.org for full | |
license details. | |
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 along | |
with FreeRTOS; if not, write to the Free Software Foundation, Inc., 59 | |
Temple Place, Suite 330, Boston, MA 02111-1307 USA. | |
*************************************************************************** | |
* * | |
* Looking for a quick start? Then check out the FreeRTOS eBook! * | |
* See http://www.FreeRTOS.org/Documentation for details * | |
* * | |
*************************************************************************** | |
1 tab == 4 spaces! | |
Please ensure to read the configuration and relevant port sections of the | |
online documentation. | |
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" | |
/* 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. By default vector 16 is used which is free on most MCF52xxx | |
* devices. | |
* | |
* 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_80() within portasm.S | |
* to be correct for whichever vector number is being used. By default interrupt | |
* controller 0 vector number 16 is used, which corresponds to vector number 80. | |
*/ | |
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 16 (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_IMRH &= ~( MCF_INTC_IPRL_INT16 ); | |
/* 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; | |
} | |
/*-----------------------------------------------------------*/ | |
void __attribute__ ((interrupt)) __cs3_isr_interrupt_119( 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 | |
} |