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/*
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.
*/
/*-----------------------------------------------------------
* Implementation of functions defined in portable.h for the PPC405 port.
*----------------------------------------------------------*/
/* Scheduler includes. */
#include "FreeRTOS.h"
#include "task.h"
/* Library includes. */
#include "xtime_l.h"
#include "xintc.h"
#include "xintc_i.h"
/*-----------------------------------------------------------*/
/* Definitions to set the initial MSR of each task. */
#define portCRITICAL_INTERRUPT_ENABLE ( 1UL << 17UL )
#define portEXTERNAL_INTERRUPT_ENABLE ( 1UL << 15UL )
#define portMACHINE_CHECK_ENABLE ( 1UL << 12UL )
#if configUSE_FPU == 1
#define portAPU_PRESENT ( 1UL << 25UL )
#define portFCM_FPU_PRESENT ( 1UL << 13UL )
#else
#define portAPU_PRESENT ( 0UL )
#define portFCM_FPU_PRESENT ( 0UL )
#endif
#define portINITIAL_MSR ( portCRITICAL_INTERRUPT_ENABLE | portEXTERNAL_INTERRUPT_ENABLE | portMACHINE_CHECK_ENABLE | portAPU_PRESENT | portFCM_FPU_PRESENT )
/*-----------------------------------------------------------*/
/*
* Setup the system timer to generate the tick interrupt.
*/
static void prvSetupTimerInterrupt( void );
/*
* The handler for the tick interrupt - defined in portasm.s.
*/
extern void vPortTickISR( void );
/*
* The handler for the yield function - defined in portasm.s.
*/
extern void vPortYield( void );
/*
* Function to start the scheduler running by starting the highest
* priority task that has thus far been created.
*/
extern void vPortStartFirstTask( void );
/*-----------------------------------------------------------*/
/* Structure used to hold the state of the interrupt controller. */
static XIntc xInterruptController;
/*-----------------------------------------------------------*/
/*
* Initialise the stack of a task to look exactly as if the task had been
* interrupted.
*
* See the header file portable.h.
*/
portSTACK_TYPE *pxPortInitialiseStack( portSTACK_TYPE *pxTopOfStack, pdTASK_CODE pxCode, void *pvParameters )
{
/* Place a known value at the bottom of the stack for debugging. */
*pxTopOfStack = 0xDEADBEEF;
pxTopOfStack--;
/* EABI stack frame. */
pxTopOfStack -= 30; /* Previous backchain and LR, R31 to R4 inclusive. */
/* Parameters in R3. */
*pxTopOfStack = ( portSTACK_TYPE ) pvParameters;
pxTopOfStack--;
*pxTopOfStack = 0x02020202UL; /* R2. */
pxTopOfStack--;
/* R1 is the stack pointer so is omitted. */
*pxTopOfStack = 0x10000001UL;; /* R0. */
pxTopOfStack--;
*pxTopOfStack = 0x00000000UL; /* USPRG0. */
pxTopOfStack--;
*pxTopOfStack = 0x00000000UL; /* CR. */
pxTopOfStack--;
*pxTopOfStack = 0x00000000UL; /* XER. */
pxTopOfStack--;
*pxTopOfStack = 0x00000000UL; /* CTR. */
pxTopOfStack--;
*pxTopOfStack = ( portSTACK_TYPE ) vPortEndScheduler; /* LR. */
pxTopOfStack--;
*pxTopOfStack = ( portSTACK_TYPE ) pxCode; /* SRR0. */
pxTopOfStack--;
*pxTopOfStack = portINITIAL_MSR;/* SRR1. */
pxTopOfStack--;
*pxTopOfStack = ( portSTACK_TYPE ) vPortEndScheduler;/* Next LR. */
pxTopOfStack--;
*pxTopOfStack = 0x00000000UL;/* Backchain. */
return pxTopOfStack;
}
/*-----------------------------------------------------------*/
portBASE_TYPE xPortStartScheduler( void )
{
prvSetupTimerInterrupt();
XExc_RegisterHandler( XEXC_ID_SYSTEM_CALL, ( XExceptionHandler ) vPortYield, ( void * ) 0 );
vPortStartFirstTask();
/* Should not get here as the tasks are now running! */
return pdFALSE;
}
/*-----------------------------------------------------------*/
void vPortEndScheduler( void )
{
/* Not implemented. */
for( ;; );
}
/*-----------------------------------------------------------*/
/*
* Hardware initialisation to generate the RTOS tick.
*/
static void prvSetupTimerInterrupt( void )
{
const unsigned portLONG ulInterval = ( ( configCPU_CLOCK_HZ / configTICK_RATE_HZ ) - 1UL );
XTime_PITClearInterrupt();
XTime_FITClearInterrupt();
XTime_WDTClearInterrupt();
XTime_WDTDisableInterrupt();
XTime_FITDisableInterrupt();
XExc_RegisterHandler( XEXC_ID_PIT_INT, ( XExceptionHandler ) vPortTickISR, ( void * ) 0 );
XTime_PITEnableAutoReload();
XTime_PITSetInterval( ulInterval );
XTime_PITEnableInterrupt();
}
/*-----------------------------------------------------------*/
void vPortISRHandler( void *pvNullDoNotUse )
{
unsigned portLONG ulInterruptStatus, ulInterruptMask = 1UL;
portBASE_TYPE xInterruptNumber;
XIntc_Config *pxInterruptController;
XIntc_VectorTableEntry *pxTable;
/* Just to remove compiler warning. */
( void ) pvNullDoNotUse;
/* Get the configuration by using the device ID - in this case it is
assumed that only one interrupt controller is being used. */
pxInterruptController = &XIntc_ConfigTable[ XPAR_XPS_INTC_0_DEVICE_ID ];
/* Which interrupts are pending? */
ulInterruptStatus = XIntc_mGetIntrStatus( pxInterruptController->BaseAddress );
for( xInterruptNumber = 0; xInterruptNumber < XPAR_INTC_MAX_NUM_INTR_INPUTS; xInterruptNumber++ )
{
if( ulInterruptStatus & 0x01UL )
{
/* Clear the pending interrupt. */
XIntc_mAckIntr( pxInterruptController->BaseAddress, ulInterruptMask );
/* Call the registered handler. */
pxTable = &( pxInterruptController->HandlerTable[ xInterruptNumber ] );
pxTable->Handler( pxTable->CallBackRef );
}
/* Check the next interrupt. */
ulInterruptMask <<= 0x01UL;
ulInterruptStatus >>= 0x01UL;
/* Have we serviced all interrupts? */
if( ulInterruptStatus == 0UL )
{
break;
}
}
}
/*-----------------------------------------------------------*/
void vPortSetupInterruptController( void )
{
extern void vPortISRWrapper( void );
/* Perform all library calls necessary to initialise the exception table
and interrupt controller. This assumes only one interrupt controller is in
use. */
XExc_mDisableExceptions( XEXC_NON_CRITICAL );
XExc_Init();
/* The library functions save the context - we then jump to a wrapper to
save the stack into the TCB. The wrapper then calls the handler defined
above. */
XExc_RegisterHandler( XEXC_ID_NON_CRITICAL_INT, ( XExceptionHandler ) vPortISRWrapper, NULL );
XIntc_Initialize( &xInterruptController, XPAR_XPS_INTC_0_DEVICE_ID );
XIntc_Start( &xInterruptController, XIN_REAL_MODE );
}
/*-----------------------------------------------------------*/
portBASE_TYPE xPortInstallInterruptHandler( unsigned portCHAR ucInterruptID, XInterruptHandler pxHandler, void *pvCallBackRef )
{
portBASE_TYPE xReturn = pdFAIL;
/* This function is defined here so the scope of xInterruptController can
remain within this file. */
if( XST_SUCCESS == XIntc_Connect( &xInterruptController, ucInterruptID, pxHandler, pvCallBackRef ) )
{
XIntc_Enable( &xInterruptController, ucInterruptID );
xReturn = pdPASS;
}
return xReturn;
}
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