FreeRTOS/Demo/MicroBlaze_Spartan-6_EthernetLite/SDKProjects/RTOSDemo/serial.c - third_party/github/FreeRTOS/FreeRTOS-Kernel - Git at Google

 /*
     FreeRTOS V8.2.0 - Copyright (C) 2015 Real Time Engineers Ltd.
     All rights reserved

     VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.

     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.  Full license text is available on the following
     link: http://www.freertos.org/a00114.html

     ***************************************************************************
      *                                                                       *
      *    FreeRTOS provides completely free yet professionally developed,    *
      *    robust, strictly quality controlled, supported, and cross          *
      *    platform software that is more than just the market leader, it     *
      *    is the industry's de facto standard.                               *
      *                                                                       *
      *    Help yourself get started quickly while simultaneously helping     *
      *    to support the FreeRTOS project by purchasing a FreeRTOS           *
      *    tutorial book, reference manual, or both:                          *
      *    http://www.FreeRTOS.org/Documentation                              *
      *                                                                       *
     ***************************************************************************

     http://www.FreeRTOS.org/FAQHelp.html - Having a problem?  Start by reading
 	the FAQ page "My application does not run, what could be wrong?".  Have you
 	defined configASSERT()?

 	http://www.FreeRTOS.org/support - In return for receiving this top quality
 	embedded software for free we request you assist our global community by
 	participating in the support forum.

 	http://www.FreeRTOS.org/training - Investing in training allows your team to
 	be as productive as possible as early as possible.  Now you can receive
 	FreeRTOS training directly from Richard Barry, CEO of Real Time Engineers
 	Ltd, and the world's leading authority on the world's leading RTOS.

     http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
     including FreeRTOS+Trace - an indispensable productivity tool, a DOS
     compatible FAT file system, and our tiny thread aware UDP/IP stack.

     http://www.FreeRTOS.org/labs - Where new FreeRTOS products go to incubate.
     Come and try FreeRTOS+TCP, our new open source TCP/IP stack for FreeRTOS.

     http://www.OpenRTOS.com - Real Time Engineers ltd. license FreeRTOS to High
     Integrity Systems ltd. to sell under the OpenRTOS brand.  Low cost OpenRTOS
     licenses offer ticketed support, indemnification and commercial middleware.

     http://www.SafeRTOS.com - High Integrity Systems also provide a safety
     engineered and independently SIL3 certified version for use in safety and
     mission critical applications that require provable dependability.

     1 tab == 4 spaces!
 */

 /*
 	BASIC INTERRUPT DRIVEN SERIAL PORT DRIVER FOR a UARTLite peripheral.
 */

 /* Scheduler includes. */
 #include "FreeRTOS.h"
 #include "queue.h"
 #include "comtest_strings.h"

 /* Library includes. */
 #include "xuartlite.h"
 #include "xuartlite_l.h"

 /* Demo application includes. */
 #include "serial.h"

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

 /* Functions that are installed as the handler for interrupts that are caused by
 Rx and Tx events respectively. */
 static void prvRxHandler( void *pvUnused, unsigned portBASE_TYPE uxByteCount );
 static void prvTxHandler( void *pvUnused, unsigned portBASE_TYPE uxByteCount );

 /* Structure that hold the state of the UARTLite peripheral used by this demo.
 This is used by the Xilinx peripheral driver API functions. */
 static XUartLite xUartLiteInstance;

 /* The queue used to hold received characters. */
 static QueueHandle_t xRxedChars;

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

 xComPortHandle xSerialPortInitMinimal( unsigned long ulWantedBaud, unsigned portBASE_TYPE uxQueueLength )
 {
 portBASE_TYPE xStatus;

 	/* The standard demo header file requires a baud rate to be passed into this
 	function.  However, in this case the baud rate is configured when the
 	hardware is generated, leaving the ulWantedBaud parameter redundant. */
 	( void ) ulWantedBaud;

 	/* Create the queue used to hold Rx characters. */
 	xRxedChars = xQueueCreate( uxQueueLength, ( unsigned portBASE_TYPE ) sizeof( signed char ) );

 	/* If the queue was created correctly, then setup the serial port
 	hardware. */
 	if( xRxedChars != NULL )
 	{
 		xStatus = XUartLite_Initialize( &xUartLiteInstance, XPAR_UARTLITE_1_DEVICE_ID );

 		if( xStatus == XST_SUCCESS )
 		{
 			/* Complete initialisation of the UART and its associated
 			interrupts. */
 			XUartLite_ResetFifos( &xUartLiteInstance );

 			/* Install the handlers that the standard Xilinx library interrupt
 			service routine will call when Rx and Tx events occur
 			respectively. */
 			XUartLite_SetRecvHandler( &xUartLiteInstance, ( XUartLite_Handler ) prvRxHandler, NULL );
 			XUartLite_SetSendHandler( &xUartLiteInstance, ( XUartLite_Handler ) prvTxHandler, NULL );

 			/* Install the standard Xilinx library interrupt handler itself.
 			*NOTE* The xPortInstallInterruptHandler() API function must be used
 			for	this purpose. */
 			xStatus = xPortInstallInterruptHandler( XPAR_INTC_0_UARTLITE_1_VEC_ID, ( XInterruptHandler ) XUartLite_InterruptHandler, &xUartLiteInstance );

 			/* Enable the interrupt in the peripheral. */
 			XUartLite_EnableIntr( xUartLiteInstance.RegBaseAddress );

 			/* Enable the interrupt in the interrupt controller.
 			*NOTE* The vPortEnableInterrupt() API function must be used for this
 			purpose. */
 			vPortEnableInterrupt( XPAR_INTC_0_UARTLITE_1_VEC_ID );
 		}

 		configASSERT( xStatus == pdPASS );
 	}

 	/* This demo file only supports a single port but something must be
 	returned to comply with the standard demo header file. */
 	return ( xComPortHandle ) 0;
 }
 /*-----------------------------------------------------------*/

 portBASE_TYPE xSerialGetChar( xComPortHandle pxPort, signed char *pcRxedChar, TickType_t xBlockTime )
 {
 	/* The port handle is not required as this driver only supports one port. */
 	( void ) pxPort;

 	/* Get the next character from the receive queue.  Return false if no
 	characters are available, or arrive before xBlockTime expires. */
 	if( xQueueReceive( xRxedChars, pcRxedChar, xBlockTime ) )
 	{
 		return pdTRUE;
 	}
 	else
 	{
 		return pdFALSE;
 	}
 }
 /*-----------------------------------------------------------*/

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

 	/* Output uxStringLength bytes starting from pcString. */
 	XUartLite_Send( &xUartLiteInstance, ( unsigned char * ) pcString, usStringLength );
 }
 /*-----------------------------------------------------------*/

 static void prvRxHandler( void *pvUnused, unsigned portBASE_TYPE uxByteCount )
 {
 signed char cRxedChar;
 portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;

 	( void ) pvUnused;
 	( void ) uxByteCount;

 	/* Place any received characters into the receive queue. */
 	while( XUartLite_IsReceiveEmpty( xUartLiteInstance.RegBaseAddress ) == pdFALSE )
 	{
 		cRxedChar = XUartLite_ReadReg( xUartLiteInstance.RegBaseAddress, XUL_RX_FIFO_OFFSET);
 		xQueueSendFromISR( xRxedChars, &cRxedChar, &xHigherPriorityTaskWoken );
 	}

 	/* If calling xQueueSendFromISR() caused a task to unblock, and the task
 	that unblocked has a priority equal to or greater than the task currently
 	in the Running state (the task that was interrupted), then
 	xHigherPriorityTaskWoken will have been set to pdTRUE internally within the
 	xQueueSendFromISR() API function.  If xHigherPriorityTaskWoken is equal to
 	pdTRUE then a context switch should be requested to ensure that the
 	interrupt returns to the highest priority task that is able	to run. */
 	portYIELD_FROM_ISR( xHigherPriorityTaskWoken );
 }
 /*-----------------------------------------------------------*/

 static void prvTxHandler( void *pvUnused, unsigned portBASE_TYPE uxByteCount )
 {
 	( void ) pvUnused;
 	( void ) uxByteCount;

 	/* Nothing to do here.  The Xilinx library function takes care of the
 	transmission. */
 	portNOP();
 }
	/*
	FreeRTOS V8.2.0 - Copyright (C) 2015 Real Time Engineers Ltd.
	All rights reserved

	VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.

	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. Full license text is available on the following
	link: http://www.freertos.org/a00114.html

	***************************************************************************
	* *
	* FreeRTOS provides completely free yet professionally developed, *
	* robust, strictly quality controlled, supported, and cross *
	* platform software that is more than just the market leader, it *
	* is the industry's de facto standard. *
	* *
	* Help yourself get started quickly while simultaneously helping *
	* to support the FreeRTOS project by purchasing a FreeRTOS *
	* tutorial book, reference manual, or both: *
	* http://www.FreeRTOS.org/Documentation *
	* *
	***************************************************************************

	http://www.FreeRTOS.org/FAQHelp.html - Having a problem? Start by reading
	the FAQ page "My application does not run, what could be wrong?". Have you
	defined configASSERT()?

	http://www.FreeRTOS.org/support - In return for receiving this top quality
	embedded software for free we request you assist our global community by
	participating in the support forum.

	http://www.FreeRTOS.org/training - Investing in training allows your team to
	be as productive as possible as early as possible. Now you can receive
	FreeRTOS training directly from Richard Barry, CEO of Real Time Engineers
	Ltd, and the world's leading authority on the world's leading RTOS.

	http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products,
	including FreeRTOS+Trace - an indispensable productivity tool, a DOS
	compatible FAT file system, and our tiny thread aware UDP/IP stack.

	http://www.FreeRTOS.org/labs - Where new FreeRTOS products go to incubate.
	Come and try FreeRTOS+TCP, our new open source TCP/IP stack for FreeRTOS.

	http://www.OpenRTOS.com - Real Time Engineers ltd. license FreeRTOS to High
	Integrity Systems ltd. to sell under the OpenRTOS brand. Low cost OpenRTOS
	licenses offer ticketed support, indemnification and commercial middleware.

	http://www.SafeRTOS.com - High Integrity Systems also provide a safety
	engineered and independently SIL3 certified version for use in safety and
	mission critical applications that require provable dependability.

	1 tab == 4 spaces!
	*/

	/*
	BASIC INTERRUPT DRIVEN SERIAL PORT DRIVER FOR a UARTLite peripheral.
	*/

	/* Scheduler includes. */
	#include "FreeRTOS.h"
	#include "queue.h"
	#include "comtest_strings.h"

	/* Library includes. */
	#include "xuartlite.h"
	#include "xuartlite_l.h"

	/* Demo application includes. */
	#include "serial.h"

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

	/* Functions that are installed as the handler for interrupts that are caused by
	Rx and Tx events respectively. */
	static void prvRxHandler( void *pvUnused, unsigned portBASE_TYPE uxByteCount );
	static void prvTxHandler( void *pvUnused, unsigned portBASE_TYPE uxByteCount );

	/* Structure that hold the state of the UARTLite peripheral used by this demo.
	This is used by the Xilinx peripheral driver API functions. */
	static XUartLite xUartLiteInstance;

	/* The queue used to hold received characters. */
	static QueueHandle_t xRxedChars;

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

	xComPortHandle xSerialPortInitMinimal( unsigned long ulWantedBaud, unsigned portBASE_TYPE uxQueueLength )
	{
	portBASE_TYPE xStatus;

	/* The standard demo header file requires a baud rate to be passed into this
	function. However, in this case the baud rate is configured when the
	hardware is generated, leaving the ulWantedBaud parameter redundant. */
	( void ) ulWantedBaud;

	/* Create the queue used to hold Rx characters. */
	xRxedChars = xQueueCreate( uxQueueLength, ( unsigned portBASE_TYPE ) sizeof( signed char ) );

	/* If the queue was created correctly, then setup the serial port
	hardware. */
	if( xRxedChars != NULL )
	{
	xStatus = XUartLite_Initialize( &xUartLiteInstance, XPAR_UARTLITE_1_DEVICE_ID );

	if( xStatus == XST_SUCCESS )
	{
	/* Complete initialisation of the UART and its associated
	interrupts. */
	XUartLite_ResetFifos( &xUartLiteInstance );

	/* Install the handlers that the standard Xilinx library interrupt
	service routine will call when Rx and Tx events occur
	respectively. */
	XUartLite_SetRecvHandler( &xUartLiteInstance, ( XUartLite_Handler ) prvRxHandler, NULL );
	XUartLite_SetSendHandler( &xUartLiteInstance, ( XUartLite_Handler ) prvTxHandler, NULL );

	/* Install the standard Xilinx library interrupt handler itself.
	NOTE The xPortInstallInterruptHandler() API function must be used
	for this purpose. */
	xStatus = xPortInstallInterruptHandler( XPAR_INTC_0_UARTLITE_1_VEC_ID, ( XInterruptHandler ) XUartLite_InterruptHandler, &xUartLiteInstance );

	/* Enable the interrupt in the peripheral. */
	XUartLite_EnableIntr( xUartLiteInstance.RegBaseAddress );

	/* Enable the interrupt in the interrupt controller.
	NOTE The vPortEnableInterrupt() API function must be used for this
	purpose. */
	vPortEnableInterrupt( XPAR_INTC_0_UARTLITE_1_VEC_ID );
	}

	configASSERT( xStatus == pdPASS );
	}

	/* This demo file only supports a single port but something must be
	returned to comply with the standard demo header file. */
	return ( xComPortHandle ) 0;
	}
	/-----------------------------------------------------------/

	portBASE_TYPE xSerialGetChar( xComPortHandle pxPort, signed char *pcRxedChar, TickType_t xBlockTime )
	{
	/* The port handle is not required as this driver only supports one port. */
	( void ) pxPort;

	/* Get the next character from the receive queue. Return false if no
	characters are available, or arrive before xBlockTime expires. */
	if( xQueueReceive( xRxedChars, pcRxedChar, xBlockTime ) )
	{
	return pdTRUE;
	}
	else
	{
	return pdFALSE;
	}
	}
	/-----------------------------------------------------------/

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

	/* Output uxStringLength bytes starting from pcString. */
	XUartLite_Send( &xUartLiteInstance, ( unsigned char * ) pcString, usStringLength );
	}
	/-----------------------------------------------------------/

	static void prvRxHandler( void *pvUnused, unsigned portBASE_TYPE uxByteCount )
	{
	signed char cRxedChar;
	portBASE_TYPE xHigherPriorityTaskWoken = pdFALSE;

	( void ) pvUnused;
	( void ) uxByteCount;

	/* Place any received characters into the receive queue. */
	while( XUartLite_IsReceiveEmpty( xUartLiteInstance.RegBaseAddress ) == pdFALSE )
	{
	cRxedChar = XUartLite_ReadReg( xUartLiteInstance.RegBaseAddress, XUL_RX_FIFO_OFFSET);
	xQueueSendFromISR( xRxedChars, &cRxedChar, &xHigherPriorityTaskWoken );
	}

	/* If calling xQueueSendFromISR() caused a task to unblock, and the task
	that unblocked has a priority equal to or greater than the task currently
	in the Running state (the task that was interrupted), then
	xHigherPriorityTaskWoken will have been set to pdTRUE internally within the
	xQueueSendFromISR() API function. If xHigherPriorityTaskWoken is equal to
	pdTRUE then a context switch should be requested to ensure that the
	interrupt returns to the highest priority task that is able to run. */
	portYIELD_FROM_ISR( xHigherPriorityTaskWoken );
	}
	/-----------------------------------------------------------/

	static void prvTxHandler( void *pvUnused, unsigned portBASE_TYPE uxByteCount )
	{
	( void ) pvUnused;
	( void ) uxByteCount;

	/* Nothing to do here. The Xilinx library function takes care of the
	transmission. */
	portNOP();
	}