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/*
* 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 );
}
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