Subversion Repositories openrisc_2011-10-31

/*
    FreeRTOS V6.1.1 - Copyright (C) 2011 Real Time Engineers Ltd.
 
    ***************************************************************************
    *                                                                         *
    * If you are:                                                             *
    *                                                                         *
    *    + New to FreeRTOS,                                                   *
    *    + Wanting to learn FreeRTOS or multitasking in general quickly       *
    *    + Looking for basic training,                                        *
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    *                                                                         *
    * then take a look at the FreeRTOS books - available as PDF or paperback  *
    *                                                                         *
    *        "Using the FreeRTOS Real Time Kernel - a Practical Guide"        *
    *                  http://www.FreeRTOS.org/Documentation                  *
    *                                                                         *
    * A pdf reference manual is also available.  Both are usually delivered   *
    * to your inbox within 20 minutes to two hours when purchased between 8am *
    * and 8pm GMT (although please allow up to 24 hours in case of            *
    * exceptional circumstances).  Thank you for your support!                *
    *                                                                         *
    ***************************************************************************
 
    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 exception 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.  See the GNU General Public License for
    more details. You should have received a copy of the GNU General Public
    License and the FreeRTOS license exception along with FreeRTOS; if not it
    can be viewed here: http://www.freertos.org/a00114.html and also obtained
    by writing to Richard Barry, contact details for whom are available on the
    FreeRTOS WEB site.
 
    1 tab == 4 spaces!
 
    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 SH2A port.
 *----------------------------------------------------------*/
 
/* Scheduler includes. */
#include "FreeRTOS.h"
#include "task.h"
 
/* Library includes. */
#include "string.h"
 
/* Hardware specifics. */
#include <iorx62n.h>
 
/*-----------------------------------------------------------*/
 
/* Tasks should start with interrupts enabled and in Supervisor mode, therefore
PSW is set with U and I set, and PM and IPL clear. */
#define portINITIAL_PSW	 ( ( portSTACK_TYPE ) 0x00030000 )
#define portINITIAL_FPSW	( ( portSTACK_TYPE ) 0x00000100 )
 
/*-----------------------------------------------------------*/
 
/*
 * Function to start the first task executing - written in asm code as direct
 * access to registers is required.
 */
extern void prvStartFirstTask( void );
 
/*
 * The tick ISR handler.  The peripheral used is configured by the application
 * via a hook/callback function.
 */
__interrupt void vTickISR( void );
 
/*-----------------------------------------------------------*/
 
extern void *pxCurrentTCB;
 
/*-----------------------------------------------------------*/
 
/*
 * See header file for description.
 */
portSTACK_TYPE *pxPortInitialiseStack( portSTACK_TYPE *pxTopOfStack, pdTASK_CODE pxCode, void *pvParameters )
{
	/* R0 is not included as it is the stack pointer. */
 
	*pxTopOfStack = 0xdeadbeef;
	pxTopOfStack--;
 	*pxTopOfStack = portINITIAL_PSW;
	pxTopOfStack--;
	*pxTopOfStack = ( portSTACK_TYPE ) pxCode;
 
	/* When debugging it can be useful if every register is set to a known
	value.  Otherwise code space can be saved by just setting the registers
	that need to be set. */
	#ifdef USE_FULL_REGISTER_INITIALISATION
	{
		pxTopOfStack--;
		*pxTopOfStack = 0xffffffff;	/* r15. */
		pxTopOfStack--;
		*pxTopOfStack = 0xeeeeeeee;
		pxTopOfStack--;
		*pxTopOfStack = 0xdddddddd;
		pxTopOfStack--;
		*pxTopOfStack = 0xcccccccc;
		pxTopOfStack--;
		*pxTopOfStack = 0xbbbbbbbb;
		pxTopOfStack--;
		*pxTopOfStack = 0xaaaaaaaa;
		pxTopOfStack--;
		*pxTopOfStack = 0x99999999;
		pxTopOfStack--;
		*pxTopOfStack = 0x88888888;
		pxTopOfStack--;
		*pxTopOfStack = 0x77777777;
		pxTopOfStack--;
		*pxTopOfStack = 0x66666666;
		pxTopOfStack--;
		*pxTopOfStack = 0x55555555;
		pxTopOfStack--;
		*pxTopOfStack = 0x44444444;
		pxTopOfStack--;
		*pxTopOfStack = 0x33333333;
		pxTopOfStack--;
		*pxTopOfStack = 0x22222222;
		pxTopOfStack--;
	}
	#else
	{
		pxTopOfStack -= 15;
	}
	#endif
 
	*pxTopOfStack = ( portSTACK_TYPE ) pvParameters; /* R1 */
	pxTopOfStack--;				
	*pxTopOfStack = portINITIAL_FPSW;
	pxTopOfStack--;
	*pxTopOfStack = 0x12345678; /* Accumulator. */
	pxTopOfStack--;
	*pxTopOfStack = 0x87654321; /* Accumulator. */
 
	return pxTopOfStack;
}
/*-----------------------------------------------------------*/
 
portBASE_TYPE xPortStartScheduler( void )
{
extern void vApplicationSetupTimerInterrupt( void );
 
	/* Use pxCurrentTCB just so it does not get optimised away. */
	if( pxCurrentTCB != NULL )
	{
		/* Call an application function to set up the timer that will generate the
		tick interrupt.  This way the application can decide which peripheral to
		use.  A demo application is provided to show a suitable example. */
		vApplicationSetupTimerInterrupt();
 
		/* Enable the software interrupt. */		
		_IEN( _ICU_SWINT ) = 1;
 
		/* Ensure the software interrupt is clear. */
		_IR( _ICU_SWINT ) = 0;
 
		/* Ensure the software interrupt is set to the kernel priority. */
		_IPR( _ICU_SWINT ) = configKERNEL_INTERRUPT_PRIORITY;
 
		/* Start the first task. */
		prvStartFirstTask();
	}
 
	/* Should not get here. */
	return pdFAIL;
}
/*-----------------------------------------------------------*/
 
#pragma vector = configTICK_VECTOR
__interrupt void vTickISR( void )
{
	/* Re-enable interrupts. */
	__enable_interrupt();
 
	/* Increment the tick, and perform any processing the new tick value
	necessitates. */
	__set_interrupt_level( configMAX_SYSCALL_INTERRUPT_PRIORITY );
	{
		vTaskIncrementTick();
	}
	__set_interrupt_level( configKERNEL_INTERRUPT_PRIORITY );
 
	/* Only select a new task if the preemptive scheduler is being used. */
	#if( configUSE_PREEMPTION == 1 )
		taskYIELD();
	#endif
}
/*-----------------------------------------------------------*/
 
void vPortEndScheduler( void )
{
	/* Not implemented as there is nothing to return to. */
}
/*-----------------------------------------------------------*/