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/*
* FreeRTOS+UDP V1.0.3 (C) 2014 Real Time Engineers ltd.
* All rights reserved
*
* This file is part of the FreeRTOS+UDP distribution. The FreeRTOS+UDP license
* terms are different to the FreeRTOS license terms.
*
* FreeRTOS+UDP uses a dual license model that allows the software to be used
* under a standard GPL open source license, or a commercial license. The
* standard GPL license (unlike the modified GPL license under which FreeRTOS
* itself is distributed) requires that all software statically linked with
* FreeRTOS+UDP is also distributed under the same GPL V2 license terms.
* Details of both license options follow:
*
* - Open source licensing -
* FreeRTOS+UDP is a free download and may be used, modified, evaluated and
* distributed without charge provided the user adheres to version two of the
* GNU General Public License (GPL) and does not remove the copyright notice or
* this text. The GPL V2 text is available on the gnu.org web site, and on the
* following URL: http://www.FreeRTOS.org/gpl-2.0.txt.
*
* - Commercial licensing -
* Businesses and individuals that for commercial or other reasons cannot comply
* with the terms of the GPL V2 license must obtain a commercial license before
* incorporating FreeRTOS+UDP into proprietary software for distribution in any
* form. Commercial licenses can be purchased from http://shop.freertos.org/udp
* and do not require any source files to be changed.
*
* FreeRTOS+UDP is distributed in the hope that it will be useful. You cannot
* use FreeRTOS+UDP unless you agree that you use the software 'as is'.
* FreeRTOS+UDP is provided WITHOUT ANY WARRANTY; without even the implied
* warranties of NON-INFRINGEMENT, MERCHANTABILITY or FITNESS FOR A PARTICULAR
* PURPOSE. Real Time Engineers Ltd. disclaims all conditions and terms, be they
* implied, expressed, or statutory.
*
* 1 tab == 4 spaces!
*
* http://www.FreeRTOS.org
* http://www.FreeRTOS.org/udp
*
*/
/* Standard includes. */
#include <stdint.h>
/* FreeRTOS includes. */
#include "FreeRTOS.h"
#include "task.h"
#include "queue.h"
#include "semphr.h"
/* Hardware abstraction. */
#include "FreeRTOS_IO.h"
/* FreeRTOS+UDP includes. */
#include "FreeRTOS_UDP_IP.h"
#include "FreeRTOS_IP_Private.h"
#include "FreeRTOS_Sockets.h"
#include "NetworkBufferManagement.h"
/* Driver includes. */
#include "lpc17xx_emac.h"
#include "lpc17xx_pinsel.h"
/* Demo includes. */
#include "NetworkInterface.h"
#if ipconfigETHERNET_DRIVER_FILTERS_FRAME_TYPES != 1
#define ipCONSIDER_FRAME_FOR_PROCESSING( pucEthernetBuffer ) eProcessBuffer
#else
#define ipCONSIDER_FRAME_FOR_PROCESSING( pucEthernetBuffer ) eConsiderFrameForProcessing( ( pucEthernetBuffer ) )
#endif
/* When a packet is ready to be sent, if it cannot be sent immediately then the
task performing the transmit will block for niTX_BUFFER_FREE_WAIT
milliseconds. It will do this a maximum of niMAX_TX_ATTEMPTS before giving
up. */
#define niTX_BUFFER_FREE_WAIT ( ( TickType_t ) 2UL / portTICK_RATE_MS )
#define niMAX_TX_ATTEMPTS ( 5 )
/* The length of the queue used to send interrupt status words from the
interrupt handler to the deferred handler task. */
#define niINTERRUPT_QUEUE_LENGTH ( 10 )
/*-----------------------------------------------------------*/
/*
* A deferred interrupt handler task that processes
*/
static void prvEMACHandlerTask( void *pvParameters );
/*-----------------------------------------------------------*/
/* The queue used to communicate Ethernet events with the IP task. */
extern xQueueHandle xNetworkEventQueue;
/* The semaphore used to wake the deferred interrupt handler task when an Rx
interrupt is received. */
static xSemaphoreHandle xEMACRxEventSemaphore = NULL;
/*-----------------------------------------------------------*/
BaseType_t xNetworkInterfaceInitialise( void )
{
EMAC_CFG_Type Emac_Config;
PINSEL_CFG_Type xPinConfig;
BaseType_t xStatus, xReturn;
extern uint8_t ucMACAddress[ 6 ];
/* Enable Ethernet Pins */
boardCONFIGURE_ENET_PINS( xPinConfig );
Emac_Config.Mode = EMAC_MODE_AUTO;
Emac_Config.pbEMAC_Addr = ucMACAddress;
xStatus = EMAC_Init( &Emac_Config );
LPC_EMAC->IntEnable &= ~( EMAC_INT_TX_DONE );
if( xStatus != ERROR )
{
vSemaphoreCreateBinary( xEMACRxEventSemaphore );
configASSERT( xEMACRxEventSemaphore );
/* The handler task is created at the highest possible priority to
ensure the interrupt handler can return directly to it. */
xTaskCreate( prvEMACHandlerTask, "EMAC", configMINIMAL_STACK_SIZE, NULL, configMAX_PRIORITIES - 1, NULL );
/* Enable the interrupt and set its priority to the minimum
interrupt priority. */
NVIC_SetPriority( ENET_IRQn, configMAC_INTERRUPT_PRIORITY );
NVIC_EnableIRQ( ENET_IRQn );
xReturn = pdPASS;
}
else
{
xReturn = pdFAIL;
}
configASSERT( xStatus != ERROR );
return xReturn;
}
/*-----------------------------------------------------------*/
BaseType_t xNetworkInterfaceOutput( xNetworkBufferDescriptor_t * const pxNetworkBuffer )
{
BaseType_t xReturn = pdFAIL;
int32_t x;
extern void EMAC_StartTransmitNextBuffer( uint32_t ulLength );
extern void EMAC_SetNextPacketToSend( uint8_t * pucBuffer );
/* Attempt to obtain access to a Tx buffer. */
for( x = 0; x < niMAX_TX_ATTEMPTS; x++ )
{
if( EMAC_CheckTransmitIndex() == TRUE )
{
/* Will the data fit in the Tx buffer? */
if( pxNetworkBuffer->xDataLength < EMAC_ETH_MAX_FLEN ) /*_RB_ The size needs to come from FreeRTOSIPConfig.h. */
{
/* Assign the buffer to the Tx descriptor that is now known to
be free. */
EMAC_SetNextPacketToSend( pxNetworkBuffer->pucEthernetBuffer );
/* The EMAC now owns the buffer. */
pxNetworkBuffer->pucEthernetBuffer = NULL;
/* Initiate the Tx. */
EMAC_StartTransmitNextBuffer( pxNetworkBuffer->xDataLength );
iptraceNETWORK_INTERFACE_TRANSMIT();
/* The Tx has been initiated. */
xReturn = pdPASS;
}
break;
}
else
{
vTaskDelay( niTX_BUFFER_FREE_WAIT );
}
}
/* Finished with the network buffer. */
vNetworkBufferRelease( pxNetworkBuffer );
return xReturn;
}
/*-----------------------------------------------------------*/
void ENET_IRQHandler( void )
{
uint32_t ulInterruptCause;
while( ( ulInterruptCause = LPC_EMAC->IntStatus ) != 0 )
{
/* Clear the interrupt. */
LPC_EMAC->IntClear = ulInterruptCause;
/* Clear fatal error conditions. NOTE: The driver does not clear all
errors, only those actually experienced. For future reference, range
errors are not actually errors so can be ignored. */
if( ( ulInterruptCause & EMAC_INT_TX_UNDERRUN ) != 0U )
{
LPC_EMAC->Command |= EMAC_CR_TX_RES;
}
/* Unblock the deferred interrupt handler task if the event was an
Rx. */
if( ( ulInterruptCause & EMAC_INT_RX_DONE ) != 0UL )
{
xSemaphoreGiveFromISR( xEMACRxEventSemaphore, NULL );
}
}
/* ulInterruptCause is used for convenience here. A context switch is
wanted, but coding portEND_SWITCHING_ISR( 1 ) would likely result in a
compiler warning. */
portEND_SWITCHING_ISR( ulInterruptCause );
}
/*-----------------------------------------------------------*/
static void prvEMACHandlerTask( void *pvParameters )
{
size_t xDataLength;
const uint16_t usCRCLength = 4;
xNetworkBufferDescriptor_t *pxNetworkBuffer;
xIPStackEvent_t xRxEvent = { eEthernetRxEvent, NULL };
/* This is not included in the header file for some reason. */
extern uint8_t *EMAC_NextPacketToRead( void );
( void ) pvParameters;
configASSERT( xEMACRxEventSemaphore );
for( ;; )
{
/* Wait for the EMAC interrupt to indicate that another packet has been
received. The while() loop is only needed if INCLUDE_vTaskSuspend is
set to 0 in FreeRTOSConfig.h. */
while( xSemaphoreTake( xEMACRxEventSemaphore, portMAX_DELAY ) == pdFALSE );
/* At least one packet has been received. */
while( EMAC_CheckReceiveIndex() != FALSE )
{
/* Obtain the length, minus the CRC. The CRC is four bytes
but the length is already minus 1. */
xDataLength = ( size_t ) EMAC_GetReceiveDataSize() - ( usCRCLength - 1U );
if( xDataLength > 0U )
{
/* Obtain a network buffer to pass this data into the
stack. No storage is required as the network buffer
will point directly to the buffer that already holds
the received data. */
pxNetworkBuffer = pxNetworkBufferGet( 0, ( TickType_t ) 0 );
if( pxNetworkBuffer != NULL )
{
pxNetworkBuffer->pucEthernetBuffer = EMAC_NextPacketToRead();
pxNetworkBuffer->xDataLength = xDataLength;
xRxEvent.pvData = ( void * ) pxNetworkBuffer;
/* Data was received and stored. Send a message to the IP
task to let it know. */
if( xQueueSendToBack( xNetworkEventQueue, &xRxEvent, ( TickType_t ) 0 ) == pdFALSE )
{
vNetworkBufferRelease( pxNetworkBuffer );
iptraceETHERNET_RX_EVENT_LOST();
}
}
else
{
iptraceETHERNET_RX_EVENT_LOST();
}
iptraceNETWORK_INTERFACE_RECEIVE();
}
/* Release the frame. */
EMAC_UpdateRxConsumeIndex();
}
}
}
/*-----------------------------------------------------------*/
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