/* | |
* FreeRTOS Kernel V10.3.0 | |
* Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved. | |
* | |
* Permission is hereby granted, free of charge, to any person obtaining a copy of | |
* this software and associated documentation files (the "Software"), to deal in | |
* the Software without restriction, including without limitation the rights to | |
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of | |
* the Software, and to permit persons to whom the Software is furnished to do so, | |
* subject to the following conditions: | |
* | |
* The above copyright notice and this permission notice shall be included in all | |
* copies or substantial portions of the Software. | |
* | |
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS | |
* FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR | |
* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER | |
* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN | |
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. | |
* | |
* http://www.FreeRTOS.org | |
* http://aws.amazon.com/freertos | |
* | |
* 1 tab == 4 spaces! | |
*/ | |
/* Kernel includes. */ | |
#include "FreeRTOS.h" | |
#include "task.h" | |
#define portINITIAL_FORMAT_VECTOR ( ( StackType_t ) 0x4000 ) | |
/* Supervisor mode set. */ | |
#define portINITIAL_STATUS_REGISTER ( ( StackType_t ) 0x2000) | |
/* The clock prescale into the timer peripheral. */ | |
#define portPRESCALE_VALUE ( ( uint8_t ) 10 ) | |
/* The clock frequency into the RTC. */ | |
#define portRTC_CLOCK_HZ ( ( uint32_t ) 1000 ) | |
asm void interrupt VectorNumber_VL1swi vPortYieldISR( void ); | |
static void prvSetupTimerInterrupt( void ); | |
/* Used to keep track of the number of nested calls to taskENTER_CRITICAL(). This | |
will be set to 0 prior to the first task being started. */ | |
static uint32_t ulCriticalNesting = 0x9999UL; | |
/*-----------------------------------------------------------*/ | |
StackType_t *pxPortInitialiseStack( StackType_t * pxTopOfStack, TaskFunction_t pxCode, void *pvParameters ) | |
{ | |
uint32_t ulOriginalA5; | |
__asm{ MOVE.L A5, ulOriginalA5 }; | |
*pxTopOfStack = (StackType_t) 0xDEADBEEF; | |
pxTopOfStack--; | |
/* Exception stack frame starts with the return address. */ | |
*pxTopOfStack = ( StackType_t ) pxCode; | |
pxTopOfStack--; | |
*pxTopOfStack = ( portINITIAL_FORMAT_VECTOR << 16UL ) | ( portINITIAL_STATUS_REGISTER ); | |
pxTopOfStack--; | |
*pxTopOfStack = ( StackType_t ) 0x0; /*FP*/ | |
pxTopOfStack -= 14; /* A5 to D0. */ | |
/* Parameter in A0. */ | |
*( pxTopOfStack + 8 ) = ( StackType_t ) pvParameters; | |
/* A5 must be maintained as it is resurved by the compiler. */ | |
*( pxTopOfStack + 13 ) = ulOriginalA5; | |
return pxTopOfStack; | |
} | |
/*-----------------------------------------------------------*/ | |
BaseType_t xPortStartScheduler( void ) | |
{ | |
extern void vPortStartFirstTask( void ); | |
ulCriticalNesting = 0UL; | |
/* Configure a timer to generate the tick interrupt. */ | |
prvSetupTimerInterrupt(); | |
/* Start the first task executing. */ | |
vPortStartFirstTask(); | |
return pdFALSE; | |
} | |
/*-----------------------------------------------------------*/ | |
static void prvSetupTimerInterrupt( void ) | |
{ | |
/* Prescale by 1 - ie no prescale. */ | |
RTCSC |= 8; | |
/* Compare match value. */ | |
RTCMOD = portRTC_CLOCK_HZ / configTICK_RATE_HZ; | |
/* Enable the RTC to generate interrupts - interrupts are already disabled | |
when this code executes. */ | |
RTCSC_RTIE = 1; | |
} | |
/*-----------------------------------------------------------*/ | |
void vPortEndScheduler( void ) | |
{ | |
/* Not implemented as there is nothing to return to. */ | |
} | |
/*-----------------------------------------------------------*/ | |
void vPortEnterCritical( void ) | |
{ | |
if( ulCriticalNesting == 0UL ) | |
{ | |
/* Guard against context switches being pended simultaneously with a | |
critical section being entered. */ | |
do | |
{ | |
portDISABLE_INTERRUPTS(); | |
if( INTC_FRC == 0UL ) | |
{ | |
break; | |
} | |
portENABLE_INTERRUPTS(); | |
} while( 1 ); | |
} | |
ulCriticalNesting++; | |
} | |
/*-----------------------------------------------------------*/ | |
void vPortExitCritical( void ) | |
{ | |
ulCriticalNesting--; | |
if( ulCriticalNesting == 0 ) | |
{ | |
portENABLE_INTERRUPTS(); | |
} | |
} | |
/*-----------------------------------------------------------*/ | |
void vPortYieldHandler( void ) | |
{ | |
uint32_t ulSavedInterruptMask; | |
ulSavedInterruptMask = portSET_INTERRUPT_MASK_FROM_ISR(); | |
{ | |
/* Note this will clear all forced interrupts - this is done for speed. */ | |
INTC_CFRC = 0x3E; | |
vTaskSwitchContext(); | |
} | |
portCLEAR_INTERRUPT_MASK_FROM_ISR( ulSavedInterruptMask ); | |
} | |
/*-----------------------------------------------------------*/ | |
void interrupt VectorNumber_Vrtc vPortTickISR( void ) | |
{ | |
uint32_t ulSavedInterruptMask; | |
/* Clear the interrupt. */ | |
RTCSC |= RTCSC_RTIF_MASK; | |
/* Increment the RTOS tick. */ | |
ulSavedInterruptMask = portSET_INTERRUPT_MASK_FROM_ISR(); | |
{ | |
if( xTaskIncrementTick() != pdFALSE ) | |
{ | |
taskYIELD(); | |
} | |
} | |
portCLEAR_INTERRUPT_MASK_FROM_ISR( ulSavedInterruptMask ); | |
} | |