Source/portable/GCC/H8S2329/port.c - third_party/github/FreeRTOS/FreeRTOS-Kernel - Git at Google

 /*
 	FreeRTOS.org V5.1.0 - 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.

     ***************************************************************************
     ***************************************************************************
     *                                                                         *
     * SAVE TIME AND MONEY!  We can port FreeRTOS.org to your own hardware,    *
     * and even write all or part of your application on your behalf.          *
     * See http://www.OpenRTOS.com for details of the services we provide to   *
     * expedite your project.                                                  *
     *                                                                         *
     ***************************************************************************
     ***************************************************************************

 	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.
 */

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


 /*-----------------------------------------------------------
  * Implementation of functions defined in portable.h for the H8S port.
  *----------------------------------------------------------*/


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

 /* When the task starts interrupts should be enabled. */
 #define portINITIAL_CCR			( ( portSTACK_TYPE ) 0x00 )

 /* Hardware specific constants used to generate the RTOS tick from the TPU. */
 #define portCLEAR_ON_TGRA_COMPARE_MATCH ( ( unsigned portCHAR ) 0x20 )
 #define portCLOCK_DIV_64				( ( unsigned portCHAR ) 0x03 )
 #define portCLOCK_DIV					( ( unsigned portLONG ) 64 )
 #define portTGRA_INTERRUPT_ENABLE		( ( unsigned portCHAR ) 0x01 )
 #define portTIMER_CHANNEL				( ( unsigned portCHAR ) 0x02 )
 #define portMSTP13						( ( unsigned portSHORT ) 0x2000 )

 /*
  * Setup TPU channel one for the RTOS tick at the requested frequency.
  */
 static void prvSetupTimerInterrupt( void );

 /*
  * The ISR used by portYIELD(). This is installed as a trap handler.
  */
 void vPortYield( void ) __attribute__ ( ( saveall, interrupt_handler ) );

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

 /*
  * See header file for description.
  */
 portSTACK_TYPE *pxPortInitialiseStack( portSTACK_TYPE *pxTopOfStack, pdTASK_CODE pxCode, void *pvParameters )
 {
 unsigned portLONG ulValue;

 	/* This requires an even address. */
 	ulValue = ( unsigned portLONG ) pxTopOfStack;
 	if( ulValue & 1UL )
 	{
 		pxTopOfStack = pxTopOfStack - 1;
 	}

 	/* Place a few bytes of known values on the bottom of the stack.
 	This is just useful for debugging. */
 	pxTopOfStack--;
 	*pxTopOfStack = 0xaa;
 	pxTopOfStack--;
 	*pxTopOfStack = 0xbb;
 	pxTopOfStack--;
 	*pxTopOfStack = 0xcc;
 	pxTopOfStack--;
 	*pxTopOfStack = 0xdd;

 	/* The initial stack mimics an interrupt stack.  First there is the program
 	counter (24 bits). */
 	ulValue = ( unsigned portLONG ) pxCode;

 	pxTopOfStack--;
 	*pxTopOfStack = ( portSTACK_TYPE ) ( ulValue & 0xff );
 	pxTopOfStack--;
 	ulValue >>= 8UL;
 	*pxTopOfStack = ( portSTACK_TYPE ) ( ulValue & 0xff );
 	pxTopOfStack--;
 	ulValue >>= 8UL;
 	*pxTopOfStack = ( portSTACK_TYPE ) ( ulValue & 0xff );

 	/* Followed by the CCR. */
 	pxTopOfStack--;
 	*pxTopOfStack = portINITIAL_CCR;

 	/* Next all the general purpose registers - with the parameters being passed
 	in ER0.  The parameter order must match that used by the compiler when the
 	"saveall" function attribute is used. */

 	/* ER6 */
 	pxTopOfStack--;
 	*pxTopOfStack = 0x66;
 	pxTopOfStack--;
 	*pxTopOfStack = 0x66;
 	pxTopOfStack--;
 	*pxTopOfStack = 0x66;
 	pxTopOfStack--;
 	*pxTopOfStack = 0x66;

 	/* ER0 */
 	ulValue = ( unsigned portLONG ) pvParameters;

 	pxTopOfStack--;
 	*pxTopOfStack = ( portSTACK_TYPE ) ( ulValue & 0xff );
 	pxTopOfStack--;
 	ulValue >>= 8UL;
 	*pxTopOfStack = ( portSTACK_TYPE ) ( ulValue & 0xff );
 	pxTopOfStack--;
 	ulValue >>= 8UL;
 	*pxTopOfStack = ( portSTACK_TYPE ) ( ulValue & 0xff );
 	pxTopOfStack--;
 	ulValue >>= 8UL;
 	*pxTopOfStack = ( portSTACK_TYPE ) ( ulValue & 0xff );

 	/* ER1 */
 	pxTopOfStack--;
 	*pxTopOfStack = 0x11;
 	pxTopOfStack--;
 	*pxTopOfStack = 0x11;
 	pxTopOfStack--;
 	*pxTopOfStack = 0x11;
 	pxTopOfStack--;
 	*pxTopOfStack = 0x11;

 	/* ER2 */
 	pxTopOfStack--;
 	*pxTopOfStack = 0x22;
 	pxTopOfStack--;
 	*pxTopOfStack = 0x22;
 	pxTopOfStack--;
 	*pxTopOfStack = 0x22;
 	pxTopOfStack--;
 	*pxTopOfStack = 0x22;

 	/* ER3 */
 	pxTopOfStack--;
 	*pxTopOfStack = 0x33;
 	pxTopOfStack--;
 	*pxTopOfStack = 0x33;
 	pxTopOfStack--;
 	*pxTopOfStack = 0x33;
 	pxTopOfStack--;
 	*pxTopOfStack = 0x33;

 	/* ER4 */
 	pxTopOfStack--;
 	*pxTopOfStack = 0x44;
 	pxTopOfStack--;
 	*pxTopOfStack = 0x44;
 	pxTopOfStack--;
 	*pxTopOfStack = 0x44;
 	pxTopOfStack--;
 	*pxTopOfStack = 0x44;

 	/* ER5 */
 	pxTopOfStack--;
 	*pxTopOfStack = 0x55;
 	pxTopOfStack--;
 	*pxTopOfStack = 0x55;
 	pxTopOfStack--;
 	*pxTopOfStack = 0x55;
 	pxTopOfStack--;
 	*pxTopOfStack = 0x55;

 	return pxTopOfStack;
 }
 /*-----------------------------------------------------------*/

 portBASE_TYPE xPortStartScheduler( void )
 {
 extern void * pxCurrentTCB;

 	/* Setup the hardware to generate the tick. */
 	prvSetupTimerInterrupt();

 	/* Restore the context of the first task that is going to run.  This
 	mirrors the function epilogue code generated by the compiler when the
 	"saveall" function attribute is used. */
 	asm volatile (
 					"MOV.L		@_pxCurrentTCB, ER6			\n\t"
 					"MOV.L		@ER6, ER7					\n\t"
 					"LDM.L     	@SP+, (ER4-ER5)				\n\t"
 					"LDM.L     	@SP+, (ER0-ER3)				\n\t"
 					"MOV.L     	@ER7+, ER6					\n\t"
 					"RTE									\n\t"
 				);

 	( void ) pxCurrentTCB;

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

 void vPortEndScheduler( void )
 {
 	/* It is unlikely that the h8 port will get stopped. */
 }
 /*-----------------------------------------------------------*/

 /*
  * Manual context switch.  This is a trap handler.  The "saveall" function
  * attribute is used so the context is saved by the compiler prologue.  All
  * we have to do is save the stack pointer.
  */
 void vPortYield( void )
 {
 	portSAVE_STACK_POINTER();
 		vTaskSwitchContext();
 	portRESTORE_STACK_POINTER();
 }
 /*-----------------------------------------------------------*/

 /*
  * The interrupt handler installed for the RTOS tick depends on whether the
  * preemptive or cooperative scheduler is being used.
  */
 #if( configUSE_PREEMPTION == 1 )

 	/*
 	 * The preemptive scheduler is used so the ISR calls vTaskSwitchContext().
 	 * The function prologue saves the context so all we have to do is save
 	 * the stack pointer.
 	 */
 	void vTickISR( void ) __attribute__ ( ( saveall, interrupt_handler ) );
 	void vTickISR( void )
 	{
 		portSAVE_STACK_POINTER();

 		vTaskIncrementTick();
 		vTaskSwitchContext();

 		/* Clear the interrupt. */
 		TSR1 &= ~0x01;

 		portRESTORE_STACK_POINTER();
 	}

 #else

 	/*
 	 * The cooperative scheduler is being used so all we have to do is
 	 * periodically increment the tick.  This can just be a normal ISR and
 	 * the "saveall" attribute is not required.
 	 */
 	void vTickISR( void ) __attribute__ ( ( interrupt_handler ) );
 	void vTickISR( void )
 	{
 		vTaskIncrementTick();

 		/* Clear the interrupt. */
 		TSR1 &= ~0x01;
 	}

 #endif
 /*-----------------------------------------------------------*/

 /*
  * Setup timer 1 compare match to generate a tick interrupt.
  */
 static void prvSetupTimerInterrupt( void )
 {
 const unsigned portLONG ulCompareMatch = ( configCPU_CLOCK_HZ / configTICK_RATE_HZ ) / portCLOCK_DIV;

 	/* Turn the module on. */
 	MSTPCR &= ~portMSTP13;

 	/* Configure timer 1. */
 	TCR1 = portCLEAR_ON_TGRA_COMPARE_MATCH | portCLOCK_DIV_64;

 	/* Configure the compare match value for a tick of configTICK_RATE_HZ. */
 	TGR1A = ulCompareMatch;

 	/* Start the timer and enable the interrupt - we can do this here as
 	interrupts are globally disabled when this function is called. */
 	TIER1 |= portTGRA_INTERRUPT_ENABLE;
 	TSTR |= portTIMER_CHANNEL;
 }
 /*-----------------------------------------------------------*/
	/*
	FreeRTOS.org V5.1.0 - 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.

	***************************************************************************
	***************************************************************************
	* *
	* SAVE TIME AND MONEY! We can port FreeRTOS.org to your own hardware, *
	* and even write all or part of your application on your behalf. *
	* See http://www.OpenRTOS.com for details of the services we provide to *
	* expedite your project. *
	* *
	***************************************************************************
	***************************************************************************

	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.
	*/

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


	/*-----------------------------------------------------------
	* Implementation of functions defined in portable.h for the H8S port.
	----------------------------------------------------------/


	/-----------------------------------------------------------/

	/* When the task starts interrupts should be enabled. */
	#define portINITIAL_CCR ( ( portSTACK_TYPE ) 0x00 )

	/* Hardware specific constants used to generate the RTOS tick from the TPU. */
	#define portCLEAR_ON_TGRA_COMPARE_MATCH ( ( unsigned portCHAR ) 0x20 )
	#define portCLOCK_DIV_64 ( ( unsigned portCHAR ) 0x03 )
	#define portCLOCK_DIV ( ( unsigned portLONG ) 64 )
	#define portTGRA_INTERRUPT_ENABLE ( ( unsigned portCHAR ) 0x01 )
	#define portTIMER_CHANNEL ( ( unsigned portCHAR ) 0x02 )
	#define portMSTP13 ( ( unsigned portSHORT ) 0x2000 )

	/*
	* Setup TPU channel one for the RTOS tick at the requested frequency.
	*/
	static void prvSetupTimerInterrupt( void );

	/*
	* The ISR used by portYIELD(). This is installed as a trap handler.
	*/
	void vPortYield( void ) __attribute__ ( ( saveall, interrupt_handler ) );

	/-----------------------------------------------------------/

	/*
	* See header file for description.
	*/
	portSTACK_TYPE pxPortInitialiseStack( portSTACK_TYPE pxTopOfStack, pdTASK_CODE pxCode, void *pvParameters )
	{
	unsigned portLONG ulValue;

	/* This requires an even address. */
	ulValue = ( unsigned portLONG ) pxTopOfStack;
	if( ulValue & 1UL )
	{
	pxTopOfStack = pxTopOfStack - 1;
	}

	/* Place a few bytes of known values on the bottom of the stack.
	This is just useful for debugging. */
	pxTopOfStack--;
	*pxTopOfStack = 0xaa;
	pxTopOfStack--;
	*pxTopOfStack = 0xbb;
	pxTopOfStack--;
	*pxTopOfStack = 0xcc;
	pxTopOfStack--;
	*pxTopOfStack = 0xdd;

	/* The initial stack mimics an interrupt stack. First there is the program
	counter (24 bits). */
	ulValue = ( unsigned portLONG ) pxCode;

	pxTopOfStack--;
	*pxTopOfStack = ( portSTACK_TYPE ) ( ulValue & 0xff );
	pxTopOfStack--;
	ulValue >>= 8UL;
	*pxTopOfStack = ( portSTACK_TYPE ) ( ulValue & 0xff );
	pxTopOfStack--;
	ulValue >>= 8UL;
	*pxTopOfStack = ( portSTACK_TYPE ) ( ulValue & 0xff );

	/* Followed by the CCR. */
	pxTopOfStack--;
	*pxTopOfStack = portINITIAL_CCR;

	/* Next all the general purpose registers - with the parameters being passed
	in ER0. The parameter order must match that used by the compiler when the
	"saveall" function attribute is used. */

	/* ER6 */
	pxTopOfStack--;
	*pxTopOfStack = 0x66;
	pxTopOfStack--;
	*pxTopOfStack = 0x66;
	pxTopOfStack--;
	*pxTopOfStack = 0x66;
	pxTopOfStack--;
	*pxTopOfStack = 0x66;

	/* ER0 */
	ulValue = ( unsigned portLONG ) pvParameters;

	pxTopOfStack--;
	*pxTopOfStack = ( portSTACK_TYPE ) ( ulValue & 0xff );
	pxTopOfStack--;
	ulValue >>= 8UL;
	*pxTopOfStack = ( portSTACK_TYPE ) ( ulValue & 0xff );
	pxTopOfStack--;
	ulValue >>= 8UL;
	*pxTopOfStack = ( portSTACK_TYPE ) ( ulValue & 0xff );
	pxTopOfStack--;
	ulValue >>= 8UL;
	*pxTopOfStack = ( portSTACK_TYPE ) ( ulValue & 0xff );

	/* ER1 */
	pxTopOfStack--;
	*pxTopOfStack = 0x11;
	pxTopOfStack--;
	*pxTopOfStack = 0x11;
	pxTopOfStack--;
	*pxTopOfStack = 0x11;
	pxTopOfStack--;
	*pxTopOfStack = 0x11;

	/* ER2 */
	pxTopOfStack--;
	*pxTopOfStack = 0x22;
	pxTopOfStack--;
	*pxTopOfStack = 0x22;
	pxTopOfStack--;
	*pxTopOfStack = 0x22;
	pxTopOfStack--;
	*pxTopOfStack = 0x22;

	/* ER3 */
	pxTopOfStack--;
	*pxTopOfStack = 0x33;
	pxTopOfStack--;
	*pxTopOfStack = 0x33;
	pxTopOfStack--;
	*pxTopOfStack = 0x33;
	pxTopOfStack--;
	*pxTopOfStack = 0x33;

	/* ER4 */
	pxTopOfStack--;
	*pxTopOfStack = 0x44;
	pxTopOfStack--;
	*pxTopOfStack = 0x44;
	pxTopOfStack--;
	*pxTopOfStack = 0x44;
	pxTopOfStack--;
	*pxTopOfStack = 0x44;

	/* ER5 */
	pxTopOfStack--;
	*pxTopOfStack = 0x55;
	pxTopOfStack--;
	*pxTopOfStack = 0x55;
	pxTopOfStack--;
	*pxTopOfStack = 0x55;
	pxTopOfStack--;
	*pxTopOfStack = 0x55;

	return pxTopOfStack;
	}
	/-----------------------------------------------------------/

	portBASE_TYPE xPortStartScheduler( void )
	{
	extern void * pxCurrentTCB;

	/* Setup the hardware to generate the tick. */
	prvSetupTimerInterrupt();

	/* Restore the context of the first task that is going to run. This
	mirrors the function epilogue code generated by the compiler when the
	"saveall" function attribute is used. */
	asm volatile (
	"MOV.L @_pxCurrentTCB, ER6 \n\t"
	"MOV.L @ER6, ER7 \n\t"
	"LDM.L @SP+, (ER4-ER5) \n\t"
	"LDM.L @SP+, (ER0-ER3) \n\t"
	"MOV.L @ER7+, ER6 \n\t"
	"RTE \n\t"
	);

	( void ) pxCurrentTCB;

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

	void vPortEndScheduler( void )
	{
	/* It is unlikely that the h8 port will get stopped. */
	}
	/-----------------------------------------------------------/

	/*
	* Manual context switch. This is a trap handler. The "saveall" function
	* attribute is used so the context is saved by the compiler prologue. All
	* we have to do is save the stack pointer.
	*/
	void vPortYield( void )
	{
	portSAVE_STACK_POINTER();
	vTaskSwitchContext();
	portRESTORE_STACK_POINTER();
	}
	/-----------------------------------------------------------/

	/*
	* The interrupt handler installed for the RTOS tick depends on whether the
	* preemptive or cooperative scheduler is being used.
	*/
	#if( configUSE_PREEMPTION == 1 )

	/*
	* The preemptive scheduler is used so the ISR calls vTaskSwitchContext().
	* The function prologue saves the context so all we have to do is save
	* the stack pointer.
	*/
	void vTickISR( void ) __attribute__ ( ( saveall, interrupt_handler ) );
	void vTickISR( void )
	{
	portSAVE_STACK_POINTER();

	vTaskIncrementTick();
	vTaskSwitchContext();

	/* Clear the interrupt. */
	TSR1 &= ~0x01;

	portRESTORE_STACK_POINTER();
	}

	#else

	/*
	* The cooperative scheduler is being used so all we have to do is
	* periodically increment the tick. This can just be a normal ISR and
	* the "saveall" attribute is not required.
	*/
	void vTickISR( void ) __attribute__ ( ( interrupt_handler ) );
	void vTickISR( void )
	{
	vTaskIncrementTick();

	/* Clear the interrupt. */
	TSR1 &= ~0x01;
	}

	#endif
	/-----------------------------------------------------------/

	/*
	* Setup timer 1 compare match to generate a tick interrupt.
	*/
	static void prvSetupTimerInterrupt( void )
	{
	const unsigned portLONG ulCompareMatch = ( configCPU_CLOCK_HZ / configTICK_RATE_HZ ) / portCLOCK_DIV;

	/* Turn the module on. */
	MSTPCR &= ~portMSTP13;

	/* Configure timer 1. */
	TCR1 = portCLEAR_ON_TGRA_COMPARE_MATCH \| portCLOCK_DIV_64;

	/* Configure the compare match value for a tick of configTICK_RATE_HZ. */
	TGR1A = ulCompareMatch;

	/* Start the timer and enable the interrupt - we can do this here as
	interrupts are globally disabled when this function is called. */
	TIER1 \|= portTGRA_INTERRUPT_ENABLE;
	TSTR \|= portTIMER_CHANNEL;
	}
	/-----------------------------------------------------------/