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

 /*
     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,                                        *
     *    + Wanting to improve your FreeRTOS skills and productivity           *
     *                                                                         *
     * 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.
 */

 /* 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 char ) 0x20 )
 #define portCLOCK_DIV_64				( ( unsigned char ) 0x03 )
 #define portCLOCK_DIV					( ( unsigned long ) 64 )
 #define portTGRA_INTERRUPT_ENABLE		( ( unsigned char ) 0x01 )
 #define portTIMER_CHANNEL				( ( unsigned char ) 0x02 )
 #define portMSTP13						( ( unsigned short ) 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 long ulValue;

 	/* This requires an even address. */
 	ulValue = ( unsigned long ) 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 long ) 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 long ) 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 long 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 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, *
	* + Wanting to improve your FreeRTOS skills and productivity *
	* *
	* 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.
	*/

	/* 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 char ) 0x20 )
	#define portCLOCK_DIV_64 ( ( unsigned char ) 0x03 )
	#define portCLOCK_DIV ( ( unsigned long ) 64 )
	#define portTGRA_INTERRUPT_ENABLE ( ( unsigned char ) 0x01 )
	#define portTIMER_CHANNEL ( ( unsigned char ) 0x02 )
	#define portMSTP13 ( ( unsigned short ) 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 long ulValue;

	/* This requires an even address. */
	ulValue = ( unsigned long ) 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 long ) 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 long ) 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 long 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;
	}
	/-----------------------------------------------------------/