blob: 1cf524704d45cf1969a1980147c97500a34d3470 [file] [log] [blame]
/*
FreeRTOS V8.0.1 - Copyright (C) 2014 Real Time Engineers Ltd.
All rights reserved
VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION.
***************************************************************************
* *
* FreeRTOS provides completely free yet professionally developed, *
* robust, strictly quality controlled, supported, and cross *
* platform software that has become a de facto standard. *
* *
* Help yourself get started quickly and support the FreeRTOS *
* project by purchasing a FreeRTOS tutorial book, reference *
* manual, or both from: http://www.FreeRTOS.org/Documentation *
* *
* Thank you! *
* *
***************************************************************************
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 from the following
link: http://www.freertos.org/a00114.html
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, books, training, latest versions,
license and Real Time Engineers Ltd. contact details.
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.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High
Integrity Systems to sell under the OpenRTOS brand. Low cost OpenRTOS
licenses offer ticketed support, indemnification and 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.
Note1: This driver is used specifically to provide an interface to the
FreeRTOS+CLI command interpreter. It is *not* intended to be a generic
serial port driver. Nor is it intended to be used as an example of an
efficient implementation. In particular, a queue is used to buffer
received characters, which is fine in this case as key presses arrive
slowly, but a DMA and/or RAM buffer should be used in place of the queue in
applications that expect higher throughput.
Note2: This driver does not attempt to handle UART errors.
*/
/* Scheduler includes. */
#include "FreeRTOS.h"
#include "task.h"
#include "queue.h"
#include "semphr.h"
/* Demo application includes. */
#include "serial.h"
/* Xilinx includes. */
#include "xuartps.h"
#include "xscugic.h"
#include "xil_exception.h"
/* The UART interrupts of interest when receiving. */
#define serRECEIVE_INTERRUPT_MASK ( XUARTPS_IXR_RXOVR | XUARTPS_IXR_RXFULL | XUARTPS_IXR_TOUT )
/* The UART interrupts of interest when transmitting. */
#define serTRANSMIT_IINTERRUPT_MASK ( XUARTPS_IXR_TXEMPTY )
/*-----------------------------------------------------------*/
/* The UART being used. */
static XUartPs xUARTInstance;
/* The interrupt controller, which is configred by the hardware setup routines
defined in main(). */
extern XScuGic xInterruptController;
/* The queue into which received key presses are placed. NOTE THE COMMENTS AT
THE TOP OF THIS FILE REGARDING THE USE OF QUEUES FOR THIS PURPOSE. */
static QueueHandle_t xRxQueue = NULL;
/* The semaphore used to indicate the end of a transmission. */
static SemaphoreHandle_t xTxCompleteSemaphore = NULL;
/*-----------------------------------------------------------*/
/*
* The UART interrupt handler is defined in this file to provide more control,
* but still uses parts of the Xilinx provided driver.
*/
void prvUART_Handler( void *pvNotUsed );
/*-----------------------------------------------------------*/
/*
* See the serial2.h header file.
*/
xComPortHandle xSerialPortInitMinimal( uint32_t ulWantedBaud, UBaseType_t uxQueueLength )
{
BaseType_t xStatus;
XUartPs_Config *pxConfig;
/* Create the queue used to hold received characters. NOTE THE COMMENTS AT
THE TOP OF THIS FILE REGARDING THE QUEUE OF QUEUES FOR THIS PURPSOE. */
xRxQueue = xQueueCreate( uxQueueLength, sizeof( char ) );
configASSERT( xRxQueue );
/* Create the semaphore used to signal the end of a transmission, then take
the semaphore so it is in the correct state the first time
xSerialSendString() is called. A block time of zero is used when taking
the semaphore as it is guaranteed to be available (it was just created). */
xTxCompleteSemaphore = xSemaphoreCreateMutex();
configASSERT( xTxCompleteSemaphore );
xSemaphoreTake( xTxCompleteSemaphore, 0 );
/* Look up the UART configuration then initialise the dirver. */
pxConfig = XUartPs_LookupConfig( XPAR_XUARTPS_0_DEVICE_ID );
/* Initialise the driver. */
xStatus = XUartPs_CfgInitialize( &xUARTInstance, pxConfig, XPAR_PS7_UART_1_BASEADDR );
configASSERT( xStatus == XST_SUCCESS );
( void ) xStatus; /* Remove compiler warning if configASSERT() is not defined. */
/* Misc. parameter configuration. */
XUartPs_SetBaudRate( &xUARTInstance, ulWantedBaud );
XUartPs_SetOperMode( &xUARTInstance, XUARTPS_OPER_MODE_NORMAL );
/* Install the interrupt service routine that is defined within this
file. */
xStatus = XScuGic_Connect( &xInterruptController, XPAR_XUARTPS_1_INTR, (Xil_ExceptionHandler) prvUART_Handler, (void *) &xUARTInstance );
configASSERT( xStatus == XST_SUCCESS );
( void ) xStatus; /* Remove compiler warning if configASSERT() is not defined. */
/* Ensure interrupts start clear. */
XUartPs_WriteReg( XPAR_PS7_UART_1_BASEADDR, XUARTPS_ISR_OFFSET, XUARTPS_IXR_MASK );
/* Enable the UART interrupt within the GIC. */
XScuGic_Enable( &xInterruptController, XPAR_XUARTPS_1_INTR );
/* Enable the interrupts of interest in the UART. */
XUartPs_SetInterruptMask( &xUARTInstance, XUARTPS_IXR_RXFULL | XUARTPS_IXR_RXOVR | XUARTPS_IXR_TOUT | XUARTPS_IXR_TXEMPTY );
/* Set the receive timeout. */
XUartPs_SetRecvTimeout( &xUARTInstance, 8 );
return ( xComPortHandle ) 0;
}
/*-----------------------------------------------------------*/
BaseType_t xSerialGetChar( xComPortHandle pxPort, signed char *pcRxedChar, TickType_t xBlockTime )
{
BaseType_t xReturn;
/* Only a single port is supported. */
( void ) pxPort;
/* Obtain a received character from the queue - entering the Blocked state
(so not consuming any processing time) to wait for a character if one is not
already available. */
xReturn = xQueueReceive( xRxQueue, pcRxedChar, xBlockTime );
return xReturn;
}
/*-----------------------------------------------------------*/
void vSerialPutString( xComPortHandle pxPort, const signed char * const pcString, unsigned short usStringLength )
{
const TickType_t xMaxWait = 200UL / portTICK_PERIOD_MS;
/* Only a single port is supported. */
( void ) pxPort;
/* Start the transmission. The interrupt service routine will complete the
transmission if necessary. */
XUartPs_Send( &xUARTInstance, ( void * ) pcString, usStringLength );
/* Wait until the string has been transmitted before exiting this function,
otherwise there is a risk the calling function will overwrite the string
pointed to by the pcString parameter while it is still being transmitted.
The calling task will wait in the Blocked state (so not consuming any
processing time) until the mutex is available. */
xSemaphoreTake( xTxCompleteSemaphore, xMaxWait );
}
/*-----------------------------------------------------------*/
signed portBASE_TYPE xSerialPutChar( xComPortHandle pxPort, signed char cOutChar, TickType_t xBlockTime )
{
/* Only a single port is supported. */
( void ) pxPort;
/* Send the character. */
XUartPs_Send( &xUARTInstance, ( void * ) &cOutChar, sizeof( cOutChar ) );
/* Wait for the transmission to be complete so the mutex is left in the
correct state for the next time vSerialPutString() is called. */
xSemaphoreTake( xTxCompleteSemaphore, xBlockTime );
return pdPASS;
}
/*-----------------------------------------------------------*/
void vSerialClose(xComPortHandle xPort)
{
/* Not supported as not required by the demo application. */
( void ) xPort;
}
/*-----------------------------------------------------------*/
void prvUART_Handler( void *pvNotUsed )
{
extern unsigned int XUartPs_SendBuffer( XUartPs *InstancePtr );
uint32_t ulActiveInterrupts, ulChannelStatusRegister;
BaseType_t xHigherPriorityTaskWoken = pdFALSE;
char cChar;
configASSERT( pvNotUsed == &xUARTInstance );
/* Remove compile warnings if configASSERT() is not defined. */
( void ) pvNotUsed;
/* Read the interrupt ID register to see which interrupt is active. */
ulActiveInterrupts = XUartPs_ReadReg(XPAR_PS7_UART_1_BASEADDR, XUARTPS_IMR_OFFSET);
ulActiveInterrupts &= XUartPs_ReadReg(XPAR_PS7_UART_1_BASEADDR, XUARTPS_ISR_OFFSET);
/* Are any receive events of interest active? */
if( ( ulActiveInterrupts & serRECEIVE_INTERRUPT_MASK ) != 0 )
{
/* Read the Channel Status Register to determine if there is any data in
the RX FIFO. */
ulChannelStatusRegister = XUartPs_ReadReg( XPAR_PS7_UART_1_BASEADDR, XUARTPS_SR_OFFSET );
/* Move data from the Rx FIFO to the Rx queue. NOTE THE COMMENTS AT THE
TOP OF THIS FILE ABOUT USING QUEUES FOR THIS PURPSOE. */
while( ( ulChannelStatusRegister & XUARTPS_SR_RXEMPTY ) == 0 )
{
cChar = XUartPs_ReadReg( XPAR_PS7_UART_1_BASEADDR, XUARTPS_FIFO_OFFSET );
/* If writing to the queue unblocks a task, and the unblocked task
has a priority above the currently running task (the task that this
interrupt interrupted), then xHigherPriorityTaskWoken will be set
to pdTRUE inside the xQueueSendFromISR() function.
xHigherPriorityTaskWoken is then passed to portYIELD_FROM_ISR() at
the end of this interrupt handler to request a context switch so the
interrupt returns directly to the (higher priority) unblocked
task. */
xQueueSendFromISR( xRxQueue, &cChar, &xHigherPriorityTaskWoken );
ulChannelStatusRegister = XUartPs_ReadReg( XPAR_PS7_UART_1_BASEADDR, XUARTPS_SR_OFFSET );
}
}
/* Are any transmit events of interest active? */
if( ( ulActiveInterrupts & serTRANSMIT_IINTERRUPT_MASK ) != 0 )
{
if( xUARTInstance.SendBuffer.RemainingBytes == 0 )
{
/* Give back the semaphore to indicate that the tranmission is
complete. If giving the semaphore unblocks a task, and the
unblocked task has a priority above the currently running task (the
task that this interrupt interrupted), then xHigherPriorityTaskWoken
will be set to pdTRUE inside the xSemaphoreGiveFromISR() function.
xHigherPriorityTaskWoken is then passed to portYIELD_FROM_ISR() at
the end of this interrupt handler to request a context switch so the
interrupt returns directly to the (higher priority) unblocked
task. */
xSemaphoreGiveFromISR( xTxCompleteSemaphore, &xHigherPriorityTaskWoken );
/* No more data to transmit. */
XUartPs_WriteReg( XPAR_PS7_UART_1_BASEADDR, XUARTPS_IDR_OFFSET, XUARTPS_IXR_TXEMPTY );
}
else
{
/* More data to send. */
XUartPs_SendBuffer( &xUARTInstance );
}
}
/* portYIELD_FROM_ISR() will request a context switch if executing this
interrupt handler caused a task to leave the blocked state, and the task
that left the blocked state has a higher priority than the currently running
task (the task this interrupt interrupted). See the comment above the calls
to xSemaphoreGiveFromISR() and xQueueSendFromISR() within this function. */
portYIELD_FROM_ISR( xHigherPriorityTaskWoken );
/* Clear the interrupt status. */
XUartPs_WriteReg( XPAR_PS7_UART_1_BASEADDR, XUARTPS_ISR_OFFSET, ulActiveInterrupts );
}