FreeRTOS/Demo/TriCore_TC1782_TriBoard_GCC/RTOSDemo/serial.c - third_party/github/FreeRTOS/FreeRTOS-Kernel - Git at Google

 /*
     FreeRTOS V7.2.0 - Copyright (C) 2012 Real Time Engineers Ltd.


     ***************************************************************************
      *                                                                       *
      *    FreeRTOS tutorial books are available in pdf and paperback.        *
      *    Complete, revised, and edited pdf reference manuals are also       *
      *    available.                                                         *
      *                                                                       *
      *    Purchasing FreeRTOS documentation will not only help you, by       *
      *    ensuring you get running as quickly as possible and with an        *
      *    in-depth knowledge of how to use FreeRTOS, it will also help       *
      *    the FreeRTOS project to continue with its mission of providing     *
      *    professional grade, cross platform, de facto standard solutions    *
      *    for microcontrollers - completely free of charge!                  *
      *                                                                       *
      *    >>> See http://www.FreeRTOS.org/Documentation for details. <<<     *
      *                                                                       *
      *    Thank you for using FreeRTOS, and 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 modification 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!

     ***************************************************************************
      *                                                                       *
      *    Having a problem?  Start by reading the FAQ "My application does   *
      *    not run, what could be wrong?                                      *
      *                                                                       *
      *    http://www.FreeRTOS.org/FAQHelp.html                               *
      *                                                                       *
     ***************************************************************************


     http://www.FreeRTOS.org - Documentation, training, latest information,
     license and contact details.

     http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
     including FreeRTOS+Trace - an indispensable productivity tool.

     Real Time Engineers ltd license FreeRTOS to High Integrity Systems, who sell
     the code with commercial support, indemnification, and middleware, under
     the OpenRTOS brand: http://www.OpenRTOS.com.  High Integrity Systems also
     provide a safety engineered and independently SIL3 certified version under
     the SafeRTOS brand: http://www.SafeRTOS.com.
 */

 /* Hardware specific includes. */
 #include <tc1782.h>
 #include <machine/intrinsics.h>
 #include <machine/cint.h>
 #include <machine/wdtcon.h>

 /* Scheduler Includes. */
 #include "FreeRTOS.h"
 #include "task.h"
 #include "queue.h"

 /* Demo Includes. */
 #include "serial.h"

 /*****************************************************************************
  * Please note!
  *
  * This file is here to provide a means of generating interrupts to test the
  * FreeRTOS tricore port.  First - it configures the UART into loopback mode,
  * and has only been used in loopback mode.  Therefore, the baud rate
  * calculation used has never been verified for correctness.  Second -
  * characters are passed into and out of the interrupt service routines using
  * character queues.  This provides a good test of the interrupt interaction,
  * context switching mechanism, and kernel loading, it is however highly
  * inefficient if the UART is being used to handle even moderate amounts of
  * data throughput.
  */


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

 /*
  * See if the Serial Transmit Interrupt is currently activated, meaning that
  * the interrupt is working through the back log of bytes that it needs to
  * send. If the ISR is not enabled, then it will be triggered to send the first
  * byte, and it will be automatically re-triggered when that byte has been
  * sent. When the queue is exhausted, the ISR disables itself.
  */
 static void prvCheckTransmit( void );

 /*
  * The transmit and receive interrupt handlers.
  */
 static void prvTxBufferInterruptHandler( int iArg ) __attribute__( ( longcall ) );
 static void prvRxInterruptHandler( int iArg )__attribute__( ( longcall ) );

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

 /* Queues used to pass bytes into and out of the interrupt handlers.
 NOTE:  This is not intended to be an example of an efficient interrupt handler,
 but instead to load the kernel and interrupt mechanisms in order to test the
 FreeRTOS port.  Using a FIFO, DMA, circular buffer, etc. architecture will
 to improve efficiency. */
 static xQueueHandle xSerialTransmitQueue = NULL;
 static xQueueHandle xSerialReceiveQueue = NULL;
 static volatile portBASE_TYPE xTransmitStatus = 0UL;

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

 xComPortHandle xSerialPortInitMinimal( unsigned long ulWantedBaud, unsigned portBASE_TYPE uxQueueLength )
 {
 unsigned long ulReloadValue = 0UL;

 	ulReloadValue = ( configPERIPHERAL_CLOCK_HZ / ( 48UL * ulWantedBaud ) ) - 1UL;

 	if( NULL == xSerialTransmitQueue )
 	{
 		xSerialTransmitQueue = xQueueCreate( uxQueueLength, sizeof( char ) );
 		xSerialReceiveQueue = xQueueCreate( uxQueueLength, sizeof( char ) );
 	}

 	/* Enable ASC0 Module. */
 	unlock_wdtcon();
 	{
 		while ( 0 != ( WDT_CON0.reg & 0x1UL ) );
 		ASC0_CLC.reg = 0x0200UL;
 	}
 	lock_wdtcon();

 	/* Disable the Operation. */
 	ASC0_CON.reg &= 0xFFFF7FFF;

 	/* Set-up the GPIO Ports. */
 	P3_IOCR0.reg = 0x00009000;	/* 3.0 ASC In, 3.1 Alt ASC Out */

 	/* Write the baud rate. */
 	ASC0_BG.reg = ulReloadValue;

 	/* Reconfigure and re-initialise the Operation. */
 	ASC0_PISEL.reg = 0UL;
 	ASC0_CON.reg = 0UL;
 	ASC0_CON.bits.M = 0x01; /* 8bit async. */
 	ASC0_CON.bits.REN = 0x01; /* Receiver enabled. */
 	ASC0_CON.bits.FDE = 0x01; /* Fractional divider enabled. */
 	ASC0_CON.bits.BRS = 0x01; /* Divide by three. */
 	ASC0_CON.bits.LB = 0x01; /* Loopback enabled. */
 	ASC0_CON.bits.R = 0x01; /* Enable the baud rate generator. */

 	/* Install the Tx interrupt. */
 	if( 0 != _install_int_handler( configINTERRUPT_PRIORITY_TX, prvTxBufferInterruptHandler, 0 ) )
 	{
 		ASC0_TBSRC.reg = configINTERRUPT_PRIORITY_TX | 0x5000UL;
 		xTransmitStatus = 0UL;
 	}

 	/* Install the Rx interrupt. */
 	if( 0 != _install_int_handler( configINTERRUPT_PRIORITY_RX, prvRxInterruptHandler, 0 ) )
 	{
 		ASC0_RSRC.reg = configINTERRUPT_PRIORITY_RX | 0x5000UL;
 	}

 	/* COM Handle is never used by demo code. */
 	return (xComPortHandle) pdPASS;
 }
 /*---------------------------------------------------------------------------*/

 void vSerialPutString( xComPortHandle pxPort, const signed char * const pcString, unsigned short usStringLength )
 {
 unsigned short usChar;

 	for( usChar = 0; usChar < usStringLength; usChar++ )
 	{
 		xSerialPutChar( pxPort, pcString[ usChar ], portMAX_DELAY );
 	}
 }
 /*---------------------------------------------------------------------------*/

 signed portBASE_TYPE xSerialGetChar( xComPortHandle pxPort, signed char *pcRxedChar, portTickType xBlockTime )
 {
 	/* Just to remove compiler warnings about unused parameters. */
 	( void )pxPort;

 	return xQueueReceive( xSerialReceiveQueue, pcRxedChar, xBlockTime );
 }
 /*---------------------------------------------------------------------------*/

 signed portBASE_TYPE xSerialPutChar( xComPortHandle pxPort, signed char cOutChar, portTickType xBlockTime )
 {
 portBASE_TYPE xReturn = pdPASS;

 	/* Just to remove compiler warnings about unused parameters. */
 	( void )pxPort;

 	/* Send the character to the interrupt handler. */
 	xReturn = xQueueSend( xSerialTransmitQueue, &cOutChar, xBlockTime );

 	/* Start the transmission of bytes if necessary. */
 	prvCheckTransmit();

 	return xReturn;
 }
 /*---------------------------------------------------------------------------*/

 static void prvTxBufferInterruptHandler( int iArg )
 {
 portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;
 unsigned char ucTx;

 	/* Just to remove compiler warnings about unused parameters. */
 	( void ) iArg;

 	/* ACK. */
 	ASC0_TBSRC.reg |= 0x4000UL;
 	xTransmitStatus = 1UL;

 	/* TBUF Can be refilled. */
 	if( pdPASS == xQueueReceiveFromISR( xSerialTransmitQueue, &ucTx, &xHigherPriorityTaskWoken ) )
 	{
 		ASC0_TBUF.reg = ucTx;
 	}
 	else
 	{
 		/* Failed to get a character out of the Queue. No longer busy. */
 		xTransmitStatus = 0UL;
 	}

 	/* Finally end ISR and switch Task if necessary. */
 	portYIELD_FROM_ISR( xHigherPriorityTaskWoken );
 }
 /*---------------------------------------------------------------------------*/

 static void prvRxInterruptHandler( int iArg )
 {
 portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;
 unsigned char ucRx;

 	/* Just to remove compiler warnings about unused parameters. */
 	( void ) iArg;

 	/* Grab the character as early as possible. */
 	ucRx = ( unsigned char ) ASC0_RBUF.reg;

 	/* ACK. */
 	ASC0_RSRC.reg |= 0x4000UL;

 	/* Frame available in RBUF. */
 	if( pdPASS != xQueueSendFromISR( xSerialReceiveQueue, &ucRx, &xHigherPriorityTaskWoken ) )
 	{
 		/* Error handling code can go here. */
 	}

 	/* Finally end ISR and switch Task if necessary. */
 	portYIELD_FROM_ISR( xHigherPriorityTaskWoken );
 }
 /*---------------------------------------------------------------------------*/

 void prvCheckTransmit( void )
 {
 	/* Check to see if the interrupt handler is working its way through the
 	buffer. */
 	if( 0 == xTransmitStatus )
 	{
 		/* Not currently operational so kick off the first byte. */
 		ASC0_TBSRC.reg |= 0x8000UL;
 	}
 }
 /*---------------------------------------------------------------------------*/
	/*
	FreeRTOS V7.2.0 - Copyright (C) 2012 Real Time Engineers Ltd.


	***************************************************************************
	* *
	* FreeRTOS tutorial books are available in pdf and paperback. *
	* Complete, revised, and edited pdf reference manuals are also *
	* available. *
	* *
	* Purchasing FreeRTOS documentation will not only help you, by *
	* ensuring you get running as quickly as possible and with an *
	* in-depth knowledge of how to use FreeRTOS, it will also help *
	* the FreeRTOS project to continue with its mission of providing *
	* professional grade, cross platform, de facto standard solutions *
	* for microcontrollers - completely free of charge! *
	* *
	* >>> See http://www.FreeRTOS.org/Documentation for details. <<< *
	* *
	* Thank you for using FreeRTOS, and 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 modification 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!

	***************************************************************************
	* *
	* Having a problem? Start by reading the FAQ "My application does *
	* not run, what could be wrong? *
	* *
	* http://www.FreeRTOS.org/FAQHelp.html *
	* *
	***************************************************************************


	http://www.FreeRTOS.org - Documentation, training, latest information,
	license and contact details.

	http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
	including FreeRTOS+Trace - an indispensable productivity tool.

	Real Time Engineers ltd license FreeRTOS to High Integrity Systems, who sell
	the code with commercial support, indemnification, and middleware, under
	the OpenRTOS brand: http://www.OpenRTOS.com. High Integrity Systems also
	provide a safety engineered and independently SIL3 certified version under
	the SafeRTOS brand: http://www.SafeRTOS.com.
	*/

	/* Hardware specific includes. */
	#include <tc1782.h>
	#include <machine/intrinsics.h>
	#include <machine/cint.h>
	#include <machine/wdtcon.h>

	/* Scheduler Includes. */
	#include "FreeRTOS.h"
	#include "task.h"
	#include "queue.h"

	/* Demo Includes. */
	#include "serial.h"

	/*****************************************************************************
	* Please note!
	*
	* This file is here to provide a means of generating interrupts to test the
	* FreeRTOS tricore port. First - it configures the UART into loopback mode,
	* and has only been used in loopback mode. Therefore, the baud rate
	* calculation used has never been verified for correctness. Second -
	* characters are passed into and out of the interrupt service routines using
	* character queues. This provides a good test of the interrupt interaction,
	* context switching mechanism, and kernel loading, it is however highly
	* inefficient if the UART is being used to handle even moderate amounts of
	* data throughput.
	*/


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

	/*
	* See if the Serial Transmit Interrupt is currently activated, meaning that
	* the interrupt is working through the back log of bytes that it needs to
	* send. If the ISR is not enabled, then it will be triggered to send the first
	* byte, and it will be automatically re-triggered when that byte has been
	* sent. When the queue is exhausted, the ISR disables itself.
	*/
	static void prvCheckTransmit( void );

	/*
	* The transmit and receive interrupt handlers.
	*/
	static void prvTxBufferInterruptHandler( int iArg ) __attribute__( ( longcall ) );
	static void prvRxInterruptHandler( int iArg )__attribute__( ( longcall ) );

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

	/* Queues used to pass bytes into and out of the interrupt handlers.
	NOTE: This is not intended to be an example of an efficient interrupt handler,
	but instead to load the kernel and interrupt mechanisms in order to test the
	FreeRTOS port. Using a FIFO, DMA, circular buffer, etc. architecture will
	to improve efficiency. */
	static xQueueHandle xSerialTransmitQueue = NULL;
	static xQueueHandle xSerialReceiveQueue = NULL;
	static volatile portBASE_TYPE xTransmitStatus = 0UL;

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

	xComPortHandle xSerialPortInitMinimal( unsigned long ulWantedBaud, unsigned portBASE_TYPE uxQueueLength )
	{
	unsigned long ulReloadValue = 0UL;

	ulReloadValue = ( configPERIPHERAL_CLOCK_HZ / ( 48UL * ulWantedBaud ) ) - 1UL;

	if( NULL == xSerialTransmitQueue )
	{
	xSerialTransmitQueue = xQueueCreate( uxQueueLength, sizeof( char ) );
	xSerialReceiveQueue = xQueueCreate( uxQueueLength, sizeof( char ) );
	}

	/* Enable ASC0 Module. */
	unlock_wdtcon();
	{
	while ( 0 != ( WDT_CON0.reg & 0x1UL ) );
	ASC0_CLC.reg = 0x0200UL;
	}
	lock_wdtcon();

	/* Disable the Operation. */
	ASC0_CON.reg &= 0xFFFF7FFF;

	/* Set-up the GPIO Ports. */
	P3_IOCR0.reg = 0x00009000; /* 3.0 ASC In, 3.1 Alt ASC Out */

	/* Write the baud rate. */
	ASC0_BG.reg = ulReloadValue;

	/* Reconfigure and re-initialise the Operation. */
	ASC0_PISEL.reg = 0UL;
	ASC0_CON.reg = 0UL;
	ASC0_CON.bits.M = 0x01; /* 8bit async. */
	ASC0_CON.bits.REN = 0x01; /* Receiver enabled. */
	ASC0_CON.bits.FDE = 0x01; /* Fractional divider enabled. */
	ASC0_CON.bits.BRS = 0x01; /* Divide by three. */
	ASC0_CON.bits.LB = 0x01; /* Loopback enabled. */
	ASC0_CON.bits.R = 0x01; /* Enable the baud rate generator. */

	/* Install the Tx interrupt. */
	if( 0 != _install_int_handler( configINTERRUPT_PRIORITY_TX, prvTxBufferInterruptHandler, 0 ) )
	{
	ASC0_TBSRC.reg = configINTERRUPT_PRIORITY_TX \| 0x5000UL;
	xTransmitStatus = 0UL;
	}

	/* Install the Rx interrupt. */
	if( 0 != _install_int_handler( configINTERRUPT_PRIORITY_RX, prvRxInterruptHandler, 0 ) )
	{
	ASC0_RSRC.reg = configINTERRUPT_PRIORITY_RX \| 0x5000UL;
	}

	/* COM Handle is never used by demo code. */
	return (xComPortHandle) pdPASS;
	}
	/---------------------------------------------------------------------------/

	void vSerialPutString( xComPortHandle pxPort, const signed char * const pcString, unsigned short usStringLength )
	{
	unsigned short usChar;

	for( usChar = 0; usChar < usStringLength; usChar++ )
	{
	xSerialPutChar( pxPort, pcString[ usChar ], portMAX_DELAY );
	}
	}
	/---------------------------------------------------------------------------/

	signed portBASE_TYPE xSerialGetChar( xComPortHandle pxPort, signed char *pcRxedChar, portTickType xBlockTime )
	{
	/* Just to remove compiler warnings about unused parameters. */
	( void )pxPort;

	return xQueueReceive( xSerialReceiveQueue, pcRxedChar, xBlockTime );
	}
	/---------------------------------------------------------------------------/

	signed portBASE_TYPE xSerialPutChar( xComPortHandle pxPort, signed char cOutChar, portTickType xBlockTime )
	{
	portBASE_TYPE xReturn = pdPASS;

	/* Just to remove compiler warnings about unused parameters. */
	( void )pxPort;

	/* Send the character to the interrupt handler. */
	xReturn = xQueueSend( xSerialTransmitQueue, &cOutChar, xBlockTime );

	/* Start the transmission of bytes if necessary. */
	prvCheckTransmit();

	return xReturn;
	}
	/---------------------------------------------------------------------------/

	static void prvTxBufferInterruptHandler( int iArg )
	{
	portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;
	unsigned char ucTx;

	/* Just to remove compiler warnings about unused parameters. */
	( void ) iArg;

	/* ACK. */
	ASC0_TBSRC.reg \|= 0x4000UL;
	xTransmitStatus = 1UL;

	/* TBUF Can be refilled. */
	if( pdPASS == xQueueReceiveFromISR( xSerialTransmitQueue, &ucTx, &xHigherPriorityTaskWoken ) )
	{
	ASC0_TBUF.reg = ucTx;
	}
	else
	{
	/* Failed to get a character out of the Queue. No longer busy. */
	xTransmitStatus = 0UL;
	}

	/* Finally end ISR and switch Task if necessary. */
	portYIELD_FROM_ISR( xHigherPriorityTaskWoken );
	}
	/---------------------------------------------------------------------------/

	static void prvRxInterruptHandler( int iArg )
	{
	portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;
	unsigned char ucRx;

	/* Just to remove compiler warnings about unused parameters. */
	( void ) iArg;

	/* Grab the character as early as possible. */
	ucRx = ( unsigned char ) ASC0_RBUF.reg;

	/* ACK. */
	ASC0_RSRC.reg \|= 0x4000UL;

	/* Frame available in RBUF. */
	if( pdPASS != xQueueSendFromISR( xSerialReceiveQueue, &ucRx, &xHigherPriorityTaskWoken ) )
	{
	/* Error handling code can go here. */
	}

	/* Finally end ISR and switch Task if necessary. */
	portYIELD_FROM_ISR( xHigherPriorityTaskWoken );
	}
	/---------------------------------------------------------------------------/

	void prvCheckTransmit( void )
	{
	/* Check to see if the interrupt handler is working its way through the
	buffer. */
	if( 0 == xTransmitStatus )
	{
	/* Not currently operational so kick off the first byte. */
	ASC0_TBSRC.reg \|= 0x8000UL;
	}
	}
	/---------------------------------------------------------------------------/