FreeRTOS-Kernel/Source/portable/Renesas/RX600/port.c

/*
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*/

/*-----------------------------------------------------------
 * Implementation of functions defined in portable.h for the SH2A port.
 *----------------------------------------------------------*/

/* Scheduler includes. */
#include "FreeRTOS.h"
#include "task.h"

/* Library includes. */
#include "string.h"

/*-----------------------------------------------------------*/

/* Dimensions the array into which the floating point context is saved.  
Allocate enough space for FPR0 to FPR15, FPUL and FPSCR, each of which is 4
bytes big.  If this number is changed then the 72 in portasm.src also needs
changing. */
#define portFLOP_REGISTERS_TO_STORE	( 18 )
#define portFLOP_STORAGE_SIZE 		( portFLOP_REGISTERS_TO_STORE * 4 )

/*-----------------------------------------------------------*/

/*
 * 
 */
void vPortYield( void );

/*
 * Function to start the first task executing.
 */
void vPortStartFirstTask( void );

/*-----------------------------------------------------------*/

/* 
 * See header file for description. 
 */
portSTACK_TYPE *pxPortInitialiseStack( portSTACK_TYPE *pxTopOfStack, pdTASK_CODE pxCode, void *pvParameters )
{
	return pxTopOfStack;
}
/*-----------------------------------------------------------*/

portBASE_TYPE xPortStartScheduler( void )
{
extern void vApplicationSetupTimerInterrupt( void );

	/* 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();

	/* Start the first task.  This will only restore the standard registers and
	not the flop registers.  This does not really matter though because the only
	flop register that is initialised to a particular value is fpscr, and it is
	only initialised to the current value, which will still be the current value
	when the first task starts executing. */
	//trapa( portSTART_SCHEDULER_TRAP_NO );

	/* Should not get here. */
	return pdFAIL;
}
/*-----------------------------------------------------------*/

void vPortEndScheduler( void )
{
	/* Not implemented as there is nothing to return to. */
}
/*-----------------------------------------------------------*/

void vPortYield( void )
{
}
/*-----------------------------------------------------------*/

portBASE_TYPE xPortUsesFloatingPoint( xTaskHandle xTask )
{
unsigned long *pulFlopBuffer;
portBASE_TYPE xReturn;
extern void * volatile pxCurrentTCB;

	/* This function tells the kernel that the task referenced by xTask is
	going to use the floating point registers and therefore requires the
	floating point registers saved as part of its context. */

	/* Passing NULL as xTask is used to indicate that the calling task is the
	subject task - so pxCurrentTCB is the task handle. */
	if( xTask == NULL )
	{
		xTask = ( xTaskHandle ) pxCurrentTCB;
	}

	/* Allocate a buffer large enough to hold all the flop registers. */
	pulFlopBuffer = ( unsigned long * ) pvPortMalloc( portFLOP_STORAGE_SIZE );
	
	if( pulFlopBuffer != NULL )
	{
		/* Start with the registers in a benign state. */
		memset( ( void * ) pulFlopBuffer, 0x00, portFLOP_STORAGE_SIZE );
		
		/* The first thing to get saved in the buffer is the FPSCR value -
		initialise this to the current FPSCR value. */
//_RB_		*pulFlopBuffer = get_fpscr();
		
		/* Use the task tag to point to the flop buffer.  Pass pointer to just 
		above the buffer because the flop save routine uses a pre-decrement. */
		vTaskSetApplicationTaskTag( xTask, ( void * ) ( pulFlopBuffer + portFLOP_REGISTERS_TO_STORE ) );		
		xReturn = pdPASS;
	}
	else
	{
		xReturn = pdFAIL;
	}
	
	return xReturn;
}
/*-----------------------------------------------------------*/

void vPortSaveFlopRegisters( void *pvBuffer )
{
}
/*-----------------------------------------------------------*/

void vPortRestoreFlopRegisters( void *pvBuffer )
{
}
/*-----------------------------------------------------------*/