/* | |
FreeRTOS.org V5.1.2 - Copyright (C) 2003-2009 Richard Barry. | |
This file is part of the FreeRTOS.org distribution. | |
FreeRTOS.org is free software; you can redistribute it and/or modify | |
it under the terms of the GNU General Public License as published by | |
the Free Software Foundation; either version 2 of the License, or | |
(at your option) any later version. | |
FreeRTOS.org 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.org; if not, write to the Free Software | |
Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA | |
A special exception to the GPL can be applied should you wish to distribute | |
a combined work that includes FreeRTOS.org, without being obliged to provide | |
the source code for any proprietary components. See the licensing section | |
of http://www.FreeRTOS.org for full details of how and when the exception | |
can be applied. | |
*************************************************************************** | |
*************************************************************************** | |
* * | |
* Get the FreeRTOS eBook! See http://www.FreeRTOS.org/Documentation * | |
* * | |
* This is a concise, step by step, 'hands on' guide that describes both * | |
* general multitasking concepts and FreeRTOS specifics. It presents and * | |
* explains numerous examples that are written using the FreeRTOS API. * | |
* Full source code for all the examples is provided in an accompanying * | |
* .zip file. * | |
* * | |
*************************************************************************** | |
*************************************************************************** | |
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 | |
} |