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/*
FreeRTOS V9.0.0rc1 - Copyright (C) 2016 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, *
* robust, strictly quality controlled, supported, and cross *
* platform software that is more than just the market leader, it *
* is the industry's de facto standard. *
* *
* Help yourself get started quickly while simultaneously helping *
* to support the FreeRTOS project by purchasing a FreeRTOS *
* tutorial book, reference manual, or both: *
* http://www.FreeRTOS.org/Documentation *
* *
***************************************************************************
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()?
http://www.FreeRTOS.org/support - In return for receiving this top quality
embedded software for free we request you assist our global community by
participating in the support forum.
http://www.FreeRTOS.org/training - Investing in training allows your team to
be as productive as possible as early as possible. Now you can receive
FreeRTOS training directly from Richard Barry, CEO of Real Time Engineers
Ltd, and the world's leading authority on the world's leading RTOS.
http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
including FreeRTOS+Trace - an indispensable productivity tool, a DOS
compatible FAT file system, and our tiny thread aware UDP/IP stack.
http://www.FreeRTOS.org/labs - Where new FreeRTOS products go to incubate.
Come and try FreeRTOS+TCP, our new open source TCP/IP stack for FreeRTOS.
http://www.OpenRTOS.com - Real Time Engineers ltd. license FreeRTOS to High
Integrity Systems ltd. to sell under the OpenRTOS brand. Low cost OpenRTOS
licenses offer ticketed support, indemnification and commercial middleware.
http://www.SafeRTOS.com - High Integrity Systems also provide a safety
engineered and independently SIL3 certified version for use in safety and
mission critical applications that require provable dependability.
1 tab == 4 spaces!
*/
/*-----------------------------------------------------------
* Implementation of functions defined in portable.h for the ST STR91x ARM9
* port.
*----------------------------------------------------------*/
/* Library includes. */
#include "91x_lib.h"
/* Standard includes. */
#include <stdlib.h>
#include <assert.h>
/* Scheduler includes. */
#include "FreeRTOS.h"
#include "task.h"
#ifndef configUSE_WATCHDOG_TICK
#error configUSE_WATCHDOG_TICK must be set to either 1 or 0 in FreeRTOSConfig.h to use either the Watchdog or timer 2 to generate the tick interrupt respectively.
#endif
/* Constants required to setup the initial stack. */
#ifndef _RUN_TASK_IN_ARM_MODE_
#define portINITIAL_SPSR ( ( StackType_t ) 0x3f ) /* System mode, THUMB mode, interrupts enabled. */
#else
#define portINITIAL_SPSR ( ( StackType_t ) 0x1f ) /* System mode, ARM mode, interrupts enabled. */
#endif
#define portINSTRUCTION_SIZE ( ( StackType_t ) 4 )
/* Constants required to handle critical sections. */
#define portNO_CRITICAL_NESTING ( ( uint32_t ) 0 )
#ifndef abs
#define abs(x) ((x)>0 ? (x) : -(x))
#endif
/**
* Toggle a led using the following algorithm:
* if ( GPIO_ReadBit(GPIO9, GPIO_Pin_2) )
* {
* GPIO_WriteBit( GPIO9, GPIO_Pin_2, Bit_RESET );
* }
* else
* {
* GPIO_WriteBit( GPIO9, GPIO_Pin_2, Bit_RESET );
* }
*
*/
#define TOGGLE_LED(port,pin) \
if ( ((((port)->DR[(pin)<<2])) & (pin)) != Bit_RESET ) \
{ \
(port)->DR[(pin) <<2] = 0x00; \
} \
else \
{ \
(port)->DR[(pin) <<2] = (pin); \
}
/*-----------------------------------------------------------*/
/* Setup the watchdog to generate the tick interrupts. */
static void prvSetupTimerInterrupt( void );
/* ulCriticalNesting will get set to zero when the first task starts. It
cannot be initialised to 0 as this will cause interrupts to be enabled
during the kernel initialisation process. */
uint32_t ulCriticalNesting = ( uint32_t ) 9999;
/* Tick interrupt routines for cooperative and preemptive operation
respectively. The preemptive version is not defined as __irq as it is called
from an asm wrapper function. */
void WDG_IRQHandler( void );
/* VIC interrupt default handler. */
static void prvDefaultHandler( void );
#if configUSE_WATCHDOG_TICK == 0
/* Used to update the OCR timer register */
static u16 s_nPulseLength;
#endif
/*-----------------------------------------------------------*/
/*
* Initialise the stack of a task to look exactly as if a call to
* portSAVE_CONTEXT had been called.
*
* See header file for description.
*/
StackType_t *pxPortInitialiseStack( StackType_t *pxTopOfStack, TaskFunction_t pxCode, void *pvParameters )
{
StackType_t *pxOriginalTOS;
pxOriginalTOS = pxTopOfStack;
/* To ensure asserts in tasks.c don't fail, although in this case the assert
is not really required. */
pxTopOfStack--;
/* Setup the initial stack of the task. The stack is set exactly as
expected by the portRESTORE_CONTEXT() macro. */
/* First on the stack is the return address - which in this case is the
start of the task. The offset is added to make the return address appear
as it would within an IRQ ISR. */
*pxTopOfStack = ( StackType_t ) pxCode + portINSTRUCTION_SIZE;
pxTopOfStack--;
*pxTopOfStack = ( StackType_t ) 0xaaaaaaaa; /* R14 */
pxTopOfStack--;
*pxTopOfStack = ( StackType_t ) pxOriginalTOS; /* Stack used when task starts goes in R13. */
pxTopOfStack--;
*pxTopOfStack = ( StackType_t ) 0x12121212; /* R12 */
pxTopOfStack--;
*pxTopOfStack = ( StackType_t ) 0x11111111; /* R11 */
pxTopOfStack--;
*pxTopOfStack = ( StackType_t ) 0x10101010; /* R10 */
pxTopOfStack--;
*pxTopOfStack = ( StackType_t ) 0x09090909; /* R9 */
pxTopOfStack--;
*pxTopOfStack = ( StackType_t ) 0x08080808; /* R8 */
pxTopOfStack--;
*pxTopOfStack = ( StackType_t ) 0x07070707; /* R7 */
pxTopOfStack--;
*pxTopOfStack = ( StackType_t ) 0x06060606; /* R6 */
pxTopOfStack--;
*pxTopOfStack = ( StackType_t ) 0x05050505; /* R5 */
pxTopOfStack--;
*pxTopOfStack = ( StackType_t ) 0x04040404; /* R4 */
pxTopOfStack--;
*pxTopOfStack = ( StackType_t ) 0x03030303; /* R3 */
pxTopOfStack--;
*pxTopOfStack = ( StackType_t ) 0x02020202; /* R2 */
pxTopOfStack--;
*pxTopOfStack = ( StackType_t ) 0x01010101; /* R1 */
pxTopOfStack--;
/* When the task starts is will expect to find the function parameter in
R0. */
*pxTopOfStack = ( StackType_t ) pvParameters; /* R0 */
pxTopOfStack--;
/* The status register is set for system mode, with interrupts enabled. */
*pxTopOfStack = ( StackType_t ) portINITIAL_SPSR;
pxTopOfStack--;
/* Interrupt flags cannot always be stored on the stack and will
instead be stored in a variable, which is then saved as part of the
tasks context. */
*pxTopOfStack = portNO_CRITICAL_NESTING;
return pxTopOfStack;
}
/*-----------------------------------------------------------*/
BaseType_t xPortStartScheduler( void )
{
extern void vPortStartFirstTask( void );
/* Start the timer that generates the tick ISR. Interrupts are disabled
here already. */
prvSetupTimerInterrupt();
/* Start the first task. */
vPortStartFirstTask();
/* Should not get here! */
return 0;
}
/*-----------------------------------------------------------*/
void vPortEndScheduler( void )
{
/* It is unlikely that the ARM port will require this function as there
is nothing to return to. */
}
/*-----------------------------------------------------------*/
/* This function is called from an asm wrapper, so does not require the __irq
keyword. */
#if configUSE_WATCHDOG_TICK == 1
static void prvFindFactors(u32 n, u16 *a, u32 *b)
{
/* This function is copied from the ST STR7 library and is
copyright STMicroelectronics. Reproduced with permission. */
u32 b0;
u16 a0;
int32_t err, err_min=n;
*a = a0 = ((n-1)/65536ul) + 1;
*b = b0 = n / *a;
for (; *a <= 256; (*a)++)
{
*b = n / *a;
err = (int32_t)*a * (int32_t)*b - (int32_t)n;
if (abs(err) > (*a / 2))
{
(*b)++;
err = (int32_t)*a * (int32_t)*b - (int32_t)n;
}
if (abs(err) < abs(err_min))
{
err_min = err;
a0 = *a;
b0 = *b;
if (err == 0) break;
}
}
*a = a0;
*b = b0;
}
/*-----------------------------------------------------------*/
static void prvSetupTimerInterrupt( void )
{
WDG_InitTypeDef xWdg;
uint16_t a;
uint32_t n = configCPU_PERIPH_HZ / configTICK_RATE_HZ, b;
/* Configure the watchdog as a free running timer that generates a
periodic interrupt. */
SCU_APBPeriphClockConfig( __WDG, ENABLE );
WDG_DeInit();
WDG_StructInit(&xWdg);
prvFindFactors( n, &a, &b );
xWdg.WDG_Prescaler = a - 1;
xWdg.WDG_Preload = b - 1;
WDG_Init( &xWdg );
WDG_ITConfig(ENABLE);
/* Configure the VIC for the WDG interrupt. */
VIC_Config( WDG_ITLine, VIC_IRQ, 10 );
VIC_ITCmd( WDG_ITLine, ENABLE );
/* Install the default handlers for both VIC's. */
VIC0->DVAR = ( uint32_t ) prvDefaultHandler;
VIC1->DVAR = ( uint32_t ) prvDefaultHandler;
WDG_Cmd(ENABLE);
}
/*-----------------------------------------------------------*/
void WDG_IRQHandler( void )
{
{
/* Increment the tick counter. */
if( xTaskIncrementTick() != pdFALSE )
{
/* Select a new task to execute. */
vTaskSwitchContext();
}
/* Clear the interrupt in the watchdog. */
WDG->SR &= ~0x0001;
}
}
#else
static void prvFindFactors(u32 n, u8 *a, u16 *b)
{
/* This function is copied from the ST STR7 library and is
copyright STMicroelectronics. Reproduced with permission. */
u16 b0;
u8 a0;
int32_t err, err_min=n;
*a = a0 = ((n-1)/256) + 1;
*b = b0 = n / *a;
for (; *a <= 256; (*a)++)
{
*b = n / *a;
err = (int32_t)*a * (int32_t)*b - (int32_t)n;
if (abs(err) > (*a / 2))
{
(*b)++;
err = (int32_t)*a * (int32_t)*b - (int32_t)n;
}
if (abs(err) < abs(err_min))
{
err_min = err;
a0 = *a;
b0 = *b;
if (err == 0) break;
}
}
*a = a0;
*b = b0;
}
/*-----------------------------------------------------------*/
static void prvSetupTimerInterrupt( void )
{
uint8_t a;
uint16_t b;
uint32_t n = configCPU_PERIPH_HZ / configTICK_RATE_HZ;
TIM_InitTypeDef timer;
SCU_APBPeriphClockConfig( __TIM23, ENABLE );
TIM_DeInit(TIM2);
TIM_StructInit(&timer);
prvFindFactors( n, &a, &b );
timer.TIM_Mode = TIM_OCM_CHANNEL_1;
timer.TIM_OC1_Modes = TIM_TIMING;
timer.TIM_Clock_Source = TIM_CLK_APB;
timer.TIM_Clock_Edge = TIM_CLK_EDGE_RISING;
timer.TIM_Prescaler = a-1;
timer.TIM_Pulse_Level_1 = TIM_HIGH;
timer.TIM_Pulse_Length_1 = s_nPulseLength = b-1;
TIM_Init (TIM2, &timer);
TIM_ITConfig(TIM2, TIM_IT_OC1, ENABLE);
/* Configure the VIC for the WDG interrupt. */
VIC_Config( TIM2_ITLine, VIC_IRQ, 10 );
VIC_ITCmd( TIM2_ITLine, ENABLE );
/* Install the default handlers for both VIC's. */
VIC0->DVAR = ( uint32_t ) prvDefaultHandler;
VIC1->DVAR = ( uint32_t ) prvDefaultHandler;
TIM_CounterCmd(TIM2, TIM_CLEAR);
TIM_CounterCmd(TIM2, TIM_START);
}
/*-----------------------------------------------------------*/
void TIM2_IRQHandler( void )
{
/* Reset the timer counter to avioid overflow. */
TIM2->OC1R += s_nPulseLength;
/* Increment the tick counter. */
if( xTaskIncrementTick() != pdFALSE )
{
/* Select a new task to run. */
vTaskSwitchContext();
}
/* Clear the interrupt in the watchdog. */
TIM2->SR &= ~TIM_FLAG_OC1;
}
#endif /* USE_WATCHDOG_TICK */
/*-----------------------------------------------------------*/
__arm __interwork void vPortEnterCritical( void )
{
/* Disable interrupts first! */
portDISABLE_INTERRUPTS();
/* Now interrupts are disabled ulCriticalNesting can be accessed
directly. Increment ulCriticalNesting to keep a count of how many times
portENTER_CRITICAL() has been called. */
ulCriticalNesting++;
}
/*-----------------------------------------------------------*/
__arm __interwork void vPortExitCritical( void )
{
if( ulCriticalNesting > portNO_CRITICAL_NESTING )
{
/* Decrement the nesting count as we are leaving a critical section. */
ulCriticalNesting--;
/* If the nesting level has reached zero then interrupts should be
re-enabled. */
if( ulCriticalNesting == portNO_CRITICAL_NESTING )
{
portENABLE_INTERRUPTS();
}
}
}
/*-----------------------------------------------------------*/
static void prvDefaultHandler( void )
{
}
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