/* | |
FreeRTOS V8.2.1 - Copyright (C) 2015 Real Time Engineers Ltd. | |
All rights reserved | |
VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION. | |
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 on the following | |
link: http://www.freertos.org/a00114.html | |
*************************************************************************** | |
* * | |
* FreeRTOS provides completely free yet professionally developed, * | |
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* * | |
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* http://www.FreeRTOS.org/Documentation * | |
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*************************************************************************** | |
http://www.FreeRTOS.org/FAQHelp.html - Having a problem? Start by reading | |
the FAQ page "My application does not run, what could be wrong?". Have you | |
defined configASSERT()? | |
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1 tab == 4 spaces! | |
*/ | |
/*----------------------------------------------------------- | |
* Implementation of functions defined in portable.h for the PIC32MZ port. | |
*----------------------------------------------------------*/ | |
#include <xc.h> | |
/* Scheduler include files. */ | |
#include "FreeRTOS.h" | |
#include "task.h" | |
#if !defined(__PIC32MZ__) | |
#error This port is designed to work with XC32 on PIC32MZ MCUs. Please update your C compiler version or settings. | |
#endif | |
#if( ( configMAX_SYSCALL_INTERRUPT_PRIORITY >= 0x7 ) || ( configMAX_SYSCALL_INTERRUPT_PRIORITY == 0 ) ) | |
#error configMAX_SYSCALL_INTERRUPT_PRIORITY must be less than 7 and greater than 0 | |
#endif | |
/* Hardware specifics. */ | |
#define portTIMER_PRESCALE 8 | |
#define portPRESCALE_BITS 1 | |
/* Bits within various registers. */ | |
#define portIE_BIT ( 0x00000001 ) | |
#define portEXL_BIT ( 0x00000002 ) | |
#define portMX_BIT ( 0x01000000 ) /* Allow access to DSP instructions. */ | |
/* Bits within the CAUSE register. */ | |
#define portCORE_SW_0 ( 0x00000100 ) | |
#define portCORE_SW_1 ( 0x00000200 ) | |
/* The EXL bit is set to ensure interrupts do not occur while the context of | |
the first task is being restored. */ | |
#define portINITIAL_SR ( portIE_BIT | portEXL_BIT | portMX_BIT ) | |
/* | |
By default port.c generates its tick interrupt from TIMER1. The user can | |
override this behaviour by: | |
1: Providing their own implementation of vApplicationSetupTickTimerInterrupt(), | |
which is the function that configures the timer. The function is defined | |
as a weak symbol in this file so if the same function name is used in the | |
application code then the version in the application code will be linked | |
into the application in preference to the version defined in this file. | |
2: Define configTICK_INTERRUPT_VECTOR to the vector number of the timer used | |
to generate the tick interrupt. For example, when timer 1 is used then | |
configTICK_INTERRUPT_VECTOR is set to _TIMER_1_VECTOR. | |
configTICK_INTERRUPT_VECTOR should be defined in FreeRTOSConfig.h. | |
3: Define configCLEAR_TICK_TIMER_INTERRUPT() to clear the interrupt in the | |
timer used to generate the tick interrupt. For example, when timer 1 is | |
used configCLEAR_TICK_TIMER_INTERRUPT() is defined to | |
IFS0CLR = _IFS0_T1IF_MASK. | |
*/ | |
#ifndef configTICK_INTERRUPT_VECTOR | |
#define configTICK_INTERRUPT_VECTOR _TIMER_1_VECTOR | |
#define configCLEAR_TICK_TIMER_INTERRUPT() IFS0CLR = _IFS0_T1IF_MASK | |
#else | |
#ifndef configCLEAR_TICK_TIMER_INTERRUPT | |
#error If configTICK_INTERRUPT_VECTOR is defined in application code then configCLEAR_TICK_TIMER_INTERRUPT must also be defined in application code. | |
#endif | |
#endif | |
/* Let the user override the pre-loading of the initial RA with the address of | |
prvTaskExitError() in case is messes up unwinding of the stack in the | |
debugger - in which case configTASK_RETURN_ADDRESS can be defined as 0 (NULL). */ | |
#ifdef configTASK_RETURN_ADDRESS | |
#define portTASK_RETURN_ADDRESS configTASK_RETURN_ADDRESS | |
#else | |
#define portTASK_RETURN_ADDRESS prvTaskExitError | |
#endif | |
/* Set configCHECK_FOR_STACK_OVERFLOW to 3 to add ISR stack checking to task | |
stack checking. A problem in the ISR stack will trigger an assert, not call the | |
stack overflow hook function (because the stack overflow hook is specific to a | |
task stack, not the ISR stack). */ | |
#if( configCHECK_FOR_STACK_OVERFLOW > 2 ) | |
/* Don't use 0xa5 as the stack fill bytes as that is used by the kernerl for | |
the task stacks, and so will legitimately appear in many positions within | |
the ISR stack. */ | |
#define portISR_STACK_FILL_BYTE 0xee | |
static const uint8_t ucExpectedStackBytes[] = { | |
portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, \ | |
portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, \ | |
portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, \ | |
portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, \ | |
portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE }; \ | |
#define portCHECK_ISR_STACK() configASSERT( ( memcmp( ( void * ) xISRStack, ( void * ) ucExpectedStackBytes, sizeof( ucExpectedStackBytes ) ) == 0 ) ) | |
#else | |
/* Define the function away. */ | |
#define portCHECK_ISR_STACK() | |
#endif /* configCHECK_FOR_STACK_OVERFLOW > 2 */ | |
/*-----------------------------------------------------------*/ | |
/* | |
* Used to catch tasks that attempt to return from their implementing function. | |
*/ | |
static void prvTaskExitError( void ); | |
/*-----------------------------------------------------------*/ | |
/* Records the interrupt nesting depth. This is initialised to one as it is | |
decremented to 0 when the first task starts. */ | |
volatile UBaseType_t uxInterruptNesting = 0x01; | |
/* Stores the task stack pointer when a switch is made to use the system stack. */ | |
UBaseType_t uxSavedTaskStackPointer = 0; | |
/* The stack used by interrupt service routines that cause a context switch. */ | |
StackType_t xISRStack[ configISR_STACK_SIZE ] = { 0 }; | |
/* The top of stack value ensures there is enough space to store 6 registers on | |
the callers stack, as some functions seem to want to do this. */ | |
const StackType_t * const xISRStackTop = &( xISRStack[ configISR_STACK_SIZE - 7 ] ); | |
/*-----------------------------------------------------------*/ | |
/* | |
* See header file for description. | |
*/ | |
StackType_t *pxPortInitialiseStack( StackType_t *pxTopOfStack, TaskFunction_t pxCode, void *pvParameters ) | |
{ | |
/* Ensure byte alignment is maintained when leaving this function. */ | |
pxTopOfStack--; | |
*pxTopOfStack = (StackType_t) 0xDEADBEEF; | |
pxTopOfStack--; | |
*pxTopOfStack = (StackType_t) 0x12345678; /* Word to which the stack pointer will be left pointing after context restore. */ | |
pxTopOfStack--; | |
*pxTopOfStack = (StackType_t) _CP0_GET_CAUSE(); | |
pxTopOfStack--; | |
*pxTopOfStack = (StackType_t) portINITIAL_SR;/* CP0_STATUS */ | |
pxTopOfStack--; | |
*pxTopOfStack = (StackType_t) pxCode; /* CP0_EPC */ | |
pxTopOfStack -= 7; /* Includes space for AC1 - AC3. */ | |
*pxTopOfStack = (StackType_t) 0x00000000; /* DSPControl */ | |
pxTopOfStack--; | |
*pxTopOfStack = (StackType_t) portTASK_RETURN_ADDRESS; /* ra */ | |
pxTopOfStack -= 15; | |
*pxTopOfStack = (StackType_t) pvParameters; /* Parameters to pass in. */ | |
pxTopOfStack -= 15; | |
return pxTopOfStack; | |
} | |
/*-----------------------------------------------------------*/ | |
static void prvTaskExitError( void ) | |
{ | |
/* A function that implements a task must not exit or attempt to return to | |
its caller as there is nothing to return to. If a task wants to exit it | |
should instead call vTaskDelete( NULL ). | |
Artificially force an assert() to be triggered if configASSERT() is | |
defined, then stop here so application writers can catch the error. */ | |
configASSERT( uxSavedTaskStackPointer == 0UL ); | |
portDISABLE_INTERRUPTS(); | |
for( ;; ); | |
} | |
/*-----------------------------------------------------------*/ | |
/* | |
* Setup a timer for a regular tick. This function uses peripheral timer 1. | |
* The function is declared weak so an application writer can use a different | |
* timer by redefining this implementation. If a different timer is used then | |
* configTICK_INTERRUPT_VECTOR must also be defined in FreeRTOSConfig.h to | |
* ensure the RTOS provided tick interrupt handler is installed on the correct | |
* vector number. When Timer 1 is used the vector number is defined as | |
* _TIMER_1_VECTOR. | |
*/ | |
__attribute__(( weak )) void vApplicationSetupTickTimerInterrupt( void ) | |
{ | |
const uint32_t ulCompareMatch = ( (configPERIPHERAL_CLOCK_HZ / portTIMER_PRESCALE) / configTICK_RATE_HZ ) - 1; | |
T1CON = 0x0000; | |
T1CONbits.TCKPS = portPRESCALE_BITS; | |
PR1 = ulCompareMatch; | |
IPC1bits.T1IP = configKERNEL_INTERRUPT_PRIORITY; | |
/* Clear the interrupt as a starting condition. */ | |
IFS0bits.T1IF = 0; | |
/* Enable the interrupt. */ | |
IEC0bits.T1IE = 1; | |
/* Start the timer. */ | |
T1CONbits.TON = 1; | |
} | |
/*-----------------------------------------------------------*/ | |
void vPortEndScheduler(void) | |
{ | |
/* Not implemented in ports where there is nothing to return to. | |
Artificially force an assert. */ | |
configASSERT( uxInterruptNesting == 1000UL ); | |
} | |
/*-----------------------------------------------------------*/ | |
BaseType_t xPortStartScheduler( void ) | |
{ | |
extern void vPortStartFirstTask( void ); | |
extern void *pxCurrentTCB; | |
#if ( configCHECK_FOR_STACK_OVERFLOW > 2 ) | |
{ | |
/* Fill the ISR stack to make it easy to asses how much is being used. */ | |
memset( ( void * ) xISRStack, portISR_STACK_FILL_BYTE, sizeof( xISRStack ) ); | |
} | |
#endif /* configCHECK_FOR_STACK_OVERFLOW > 2 */ | |
/* Clear the software interrupt flag. */ | |
IFS0CLR = _IFS0_CS0IF_MASK; | |
/* Set software timer priority. */ | |
IPC0CLR = _IPC0_CS0IP_MASK; | |
IPC0SET = ( configKERNEL_INTERRUPT_PRIORITY << _IPC0_CS0IP_POSITION ); | |
/* Enable software interrupt. */ | |
IEC0CLR = _IEC0_CS0IE_MASK; | |
IEC0SET = 1 << _IEC0_CS0IE_POSITION; | |
/* Setup the timer to generate the tick. Interrupts will have been | |
disabled by the time we get here. */ | |
vApplicationSetupTickTimerInterrupt(); | |
/* Kick off the highest priority task that has been created so far. | |
Its stack location is loaded into uxSavedTaskStackPointer. */ | |
uxSavedTaskStackPointer = *( UBaseType_t * ) pxCurrentTCB; | |
vPortStartFirstTask(); | |
/* Should never get here as the tasks will now be executing! Call the task | |
exit error function to prevent compiler warnings about a static function | |
not being called in the case that the application writer overrides this | |
functionality by defining configTASK_RETURN_ADDRESS. */ | |
prvTaskExitError(); | |
return pdFALSE; | |
} | |
/*-----------------------------------------------------------*/ | |
void vPortIncrementTick( void ) | |
{ | |
UBaseType_t uxSavedStatus; | |
uxSavedStatus = uxPortSetInterruptMaskFromISR(); | |
{ | |
if( xTaskIncrementTick() != pdFALSE ) | |
{ | |
/* Pend a context switch. */ | |
_CP0_BIS_CAUSE( portCORE_SW_0 ); | |
} | |
} | |
vPortClearInterruptMaskFromISR( uxSavedStatus ); | |
/* Look for the ISR stack getting near or past its limit. */ | |
portCHECK_ISR_STACK(); | |
/* Clear timer interrupt. */ | |
configCLEAR_TICK_TIMER_INTERRUPT(); | |
} | |
/*-----------------------------------------------------------*/ | |
UBaseType_t uxPortSetInterruptMaskFromISR( void ) | |
{ | |
UBaseType_t uxSavedStatusRegister; | |
__builtin_disable_interrupts(); | |
uxSavedStatusRegister = _CP0_GET_STATUS() | 0x01; | |
/* This clears the IPL bits, then sets them to | |
configMAX_SYSCALL_INTERRUPT_PRIORITY. This function should not be called | |
from an interrupt that has a priority above | |
configMAX_SYSCALL_INTERRUPT_PRIORITY so, when used correctly, the action | |
can only result in the IPL being unchanged or raised, and therefore never | |
lowered. */ | |
_CP0_SET_STATUS( ( ( uxSavedStatusRegister & ( ~portALL_IPL_BITS ) ) ) | ( configMAX_SYSCALL_INTERRUPT_PRIORITY << portIPL_SHIFT ) ); | |
return uxSavedStatusRegister; | |
} | |
/*-----------------------------------------------------------*/ | |
void vPortClearInterruptMaskFromISR( UBaseType_t uxSavedStatusRegister ) | |
{ | |
_CP0_SET_STATUS( uxSavedStatusRegister ); | |
} | |
/*-----------------------------------------------------------*/ | |