port.c

FreeRTOS - V5.1.1 Last Update: Nov 20 2008 http://sourceforge.net/projects/freertos/

/*
	FreeRTOS.org V5.1.1 - Copyright (C) 2003-2008 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.

    ***************************************************************************
    ***************************************************************************
    *                                                                         *
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	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 
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*/

#include "FreeRTOS.h"
#include "task.h"
#include "mb96348hs.h"

/*-----------------------------------------------------------
 * Implementation of functions defined in portable.h for the 16FX port.
 *----------------------------------------------------------*/

/* 
 * Get current value of DPR and ADB registers 
 */
portSTACK_TYPE xGet_DPR_ADB_bank( void ); 

/* 
 * Get current value of DTB and PCB registers 
 */
portSTACK_TYPE xGet_DTB_PCB_bank( void );

/*
 * Sets up the periodic ISR used for the RTOS tick.  This uses RLT0, but
 * can be done using any given RLT.
 */
static void prvSetupRLT0Interrupt( void );

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

/* 
 * We require the address of the pxCurrentTCB variable, but don't want to know
 * any details of its type. 
 */
typedef void tskTCB;
extern volatile tskTCB * volatile pxCurrentTCB;

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

/* 
 * Macro to save a task context to the task stack. This macro  copies the 
 * saved context (AH:AL, DPR:ADB, DTB:PCB , PC and PS) from  the   system 
 * stack to task stack pointed by user stack pointer ( USP  for SMALL and 
 * MEDIUM memory model amd USB:USP for COMPACT  and LARGE memory model ),
 * then  it pushes the general purpose registers RW0-RW7  on  to the task 
 * stack. Finally the  resultant  stack  pointer  value is saved into the 
 * task  control  block  so  it  can  be retrieved the next time the task 
 * executes.
 */ 
#if( ( configMEMMODEL == portSMALL ) || ( configMEMMODEL == portMEDIUM ) )

	#define portSAVE_CONTEXT()											\
			{	__asm(" POPW  A ");										\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" PUSHW  A ");									\
				__asm(" OR   CCR,#H'20 ");								\
	    		__asm(" POPW  A ");										\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" PUSHW  A ");									\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" POPW  A ");										\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" PUSHW  A ");									\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" POPW  A ");										\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" PUSHW  A ");									\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" POPW  A ");										\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" PUSHW  A ");									\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" POPW  A ");										\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" PUSHW  A ");									\
				__asm(" PUSHW (RW0,RW1,RW2,RW3,RW4,RW5,RW6,RW7) ");		\
				__asm(" MOVW A, _pxCurrentTCB ");						\
				__asm(" MOVW A, SP ");									\
  				__asm(" SWAPW ");										\
				__asm(" MOVW @AL, AH ");								\
				__asm(" OR   CCR,#H'20 ");								\
			}

/* 
 * Macro to restore a task context from the task stack.  This is effecti-
 * vely the reverse of SAVE_CONTEXT(). First the stack pointer  value
 * (USP for SMALL and MEDIUM memory model amd  USB:USP  for  COMPACT  and 
 * LARGE memory model ) is loaded from the task  control block.  Next the 
 * value of all the general purpose registers RW0-RW7 is retrieved. Fina-
 * lly it copies of the context ( AH:AL,  DPR:ADB, DTB:PCB, PC and PS) of 
 * the task to be executed upon RETI from user stack to system stack.  
 */
 
	#define portRESTORE_CONTEXT()										\
			{	__asm(" MOVW A, _pxCurrentTCB ");						\
				__asm(" MOVW A, @A ");									\
  				__asm(" AND  CCR,#H'DF ");  							\
  				__asm(" MOVW SP, A ");									\
				__asm(" POPW (RW0,RW1,RW2,RW3,RW4,RW5,RW6,RW7) ");		\
				__asm(" POPW  A ");										\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" PUSHW  A ");									\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" POPW  A ");										\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" PUSHW  A ");									\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" POPW  A ");										\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" PUSHW  A ");									\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" POPW  A ");										\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" PUSHW  A ");									\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" POPW  A ");										\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" PUSHW  A ");									\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" POPW  A ");										\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" PUSHW  A ");									\
			}
		
#elif( ( configMEMMODEL == portCOMPACT ) || ( configMEMMODEL == portLARGE ) )

	#define portSAVE_CONTEXT()											\
			{	__asm(" POPW  A ");										\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" PUSHW  A ");									\
				__asm(" OR   CCR,#H'20 ");								\
	    		__asm(" POPW  A ");										\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" PUSHW  A ");									\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" POPW  A ");										\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" PUSHW  A ");									\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" POPW  A ");										\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" PUSHW  A ");									\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" POPW  A ");										\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" PUSHW  A ");									\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" POPW  A ");										\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" PUSHW  A ");									\
				__asm(" PUSHW (RW0,RW1,RW2,RW3,RW4,RW5,RW6,RW7) ");		\
				__asm(" MOVL A, _pxCurrentTCB ");						\
				__asm(" MOVL RL2, A ");									\
				__asm(" MOVW A, SP ");									\
				__asm(" MOVW @RL2+0, A ");								\
				__asm(" MOV A, USB ");									\
				__asm(" MOV @RL2+2, A ");								\
			}	
            
	#define portRESTORE_CONTEXT()										\
			{	__asm(" MOVL A, _pxCurrentTCB ");						\
				__asm(" MOVL RL2, A ");									\
				__asm(" MOVW A, @RL2+0 ");								\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" MOVW SP, A ");									\
				__asm(" MOV A, @RL2+2 ");								\
				__asm(" MOV USB, A ");									\
				__asm(" POPW (RW0,RW1,RW2,RW3,RW4,RW5,RW6,RW7) ");		\
				__asm(" POPW  A ");										\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" PUSHW  A ");									\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" POPW  A ");										\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" PUSHW  A ");									\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" POPW  A ");										\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" PUSHW  A ");									\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" POPW  A ");										\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" PUSHW  A ");									\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" POPW  A ");										\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" PUSHW  A ");									\
				__asm(" AND  CCR,#H'DF ");  							\
				__asm(" POPW  A ");										\
				__asm(" OR   CCR,#H'20 ");								\
				__asm(" PUSHW  A ");									\
			}
#endif

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

/* 
 * Functions for obtaining the current value  of  DPR:ADB, DTB:PCB bank registers
 */
 
#pragma asm

        .GLOBAL    _xGet_DPR_ADB_bank
        .GLOBAL    _xGet_DTB_PCB_bank
        .SECTION   CODE, CODE, ALIGN=1

_xGet_DPR_ADB_bank:

    MOV A, DPR
    SWAP
    MOV A, ADB
    ORW A
	#if configMEMMODEL == portMEDIUM || configMEMMODEL == portLARGE
		RETP
	#elif configMEMMODEL == portSMALL || configMEMMODEL == portCOMPACT   
		RET
	#endif 


_xGet_DTB_PCB_bank: