/*
	FreeRTOS.org V5.2.0 - 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 (version 2) as published
	by the Free Software Foundation and modified by the FreeRTOS exception.

	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 is included to allow you 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.


	***************************************************************************
	*                                                                         *
	* 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.                                                              *
	*                                                                         *
	***************************************************************************

	1 tab == 4 spaces!

	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.
*/

#include "FreeRTOS.h"
#include "task.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: