/*
    FreeRTOS V7.0.2 - Copyright (C) 2011 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!

    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.
*/

/* FreeRTOS includes. */
#include "FreeRTOS.h"
#include "task.h"
#include "queue.h"

/* BSP includes. */
#include "xemaclite.h"
#include "xintc_l.h"

/* lwIP includes. */
#include "lwip/opt.h"
#include "lwip/def.h"
#include "lwip/mem.h"
#include "lwip/pbuf.h"
#include "lwip/sys.h"
#include <lwip/stats.h>
#include <lwip/snmp.h>
#include "netif/etharp.h"

/* Define those to better describe your network interface. */
#define IFNAME0 'e'
#define IFNAME1 'l'

/* When a packet is ready to be sent, if it cannot be sent immediately then
 * the task performing the transmit will block for netifTX_BUFFER_FREE_WAIT
 * milliseconds.  It will do this a maximum of netifMAX_TX_ATTEMPTS before
 * giving up.
 */
#define netifTX_BUFFER_FREE_WAIT	( ( portTickType ) 2UL / portTICK_RATE_MS )
#define netifMAX_TX_ATTEMPTS		( 5 )

#define netifMAX_MTU 1500

struct xEthernetIf
{
	struct eth_addr *ethaddr;
	/* Add whatever per-interface state that is needed here. */
};

/*
 * Copy the received data into a pbuf.
 */
static struct pbuf *prvLowLevelInput( const unsigned char * const pucInputData, unsigned short usDataLength );

/*
 * Send data from a pbuf to the hardware.
 */
static err_t prvLowLevelOutput( struct netif *pxNetIf, struct pbuf *p );

/*
 * Perform any hardware and/or driver initialisation necessary.
 */
static void prvLowLevelInit( struct netif *pxNetIf );

/*
 * Functions that get registered as the Rx and Tx interrupt handers
 * respectively.
 */
static void prvRxHandler( void *pvNetIf );
static void prvTxHandler( void *pvUnused );


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

/* The instance of the xEmacLite IP being used in this driver. */
static XEmacLite xEMACInstance;

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

/**
 * In this function, the hardware should be initialized.
 * Called from ethernetif_init().
 *
 * @param pxNetIf the already initialized lwip network interface structure
 *		for this etherpxNetIf
 */
static void prvLowLevelInit( struct netif *pxNetIf )
{
portBASE_TYPE xStatus;
extern void vInitialisePHY( XEmacLite *xemaclitep );
unsigned portBASE_TYPE uxOriginalPriority;

	/* Hardware initialisation can take some time, so temporarily lower the
	task priority to ensure other functionality is not adversely effected.
	The priority will get raised again before this function exits. */
	uxOriginalPriority = uxTaskPriorityGet( NULL );
	vTaskPrioritySet( NULL, tskIDLE_PRIORITY );

	/* set MAC hardware address length */
	pxNetIf->hwaddr_len = ETHARP_HWADDR_LEN;

	/* set MAC hardware address */
	pxNetIf->hwaddr[ 0 ] = configMAC_ADDR0;
	pxNetIf->hwaddr[ 1 ] = configMAC_ADDR1;
	pxNetIf->hwaddr[ 2 ] = configMAC_ADDR2;
	pxNetIf->hwaddr[ 3 ] = configMAC_ADDR3;
	pxNetIf->hwaddr[ 4 ] = configMAC_ADDR4;
	pxNetIf->hwaddr[ 5 ] = configMAC_ADDR5;

	/* device capabilities */
	pxNetIf->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP | NETIF_FLAG_LINK_UP;

	/* maximum transfer unit */
	pxNetIf->mtu = netifMAX_MTU;

	/* Broadcast capability */
	pxNetIf->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP | NETIF_FLAG_LINK_UP;

	/* Initialize the mac */
	xStatus = XEmacLite_Initialize( &xEMACInstance, XPAR_EMACLITE_0_DEVICE_ID );

	if( xStatus == XST_SUCCESS )
	{
		/* Set mac address */
		XEmacLite_SetMacAddress( &xEMACInstance, ( Xuint8* )( pxNetIf->hwaddr ) );

		/* Flush any frames already received */
		XEmacLite_FlushReceive( &xEMACInstance );

		/* Set Rx, Tx interrupt handlers */
		XEmacLite_SetRecvHandler( &xEMACInstance, ( void * ) pxNetIf, prvRxHandler );
		XEmacLite_SetSendHandler( &xEMACInstance, NULL, prvTxHandler );

		/* Enable Rx, Tx interrupts */
		XEmacLite_EnableInterrupts( &xEMACInstance );

		/* Install the standard Xilinx library interrupt handler itself.
		*NOTE* The xPortInstallInterruptHandler() API function must be used
		for	this purpose. */
		xStatus = xPortInstallInterruptHandler( XPAR_INTC_0_EMACLITE_0_VEC_ID, ( XInterruptHandler ) XEmacLite_InterruptHandler, &xEMACInstance );

		vInitialisePHY( &xEMACInstance );

		/* Enable the interrupt in the interrupt controller.
		*NOTE* The vPortEnableInterrupt() API function must be used for this
		purpose. */
		vPortEnableInterrupt( XPAR_INTC_0_EMACLITE_0_VEC_ID );
	}

	/* Reset the task priority back to its original value. */
	vTaskPrioritySet( NULL, uxOriginalPriority );

	configASSERT( xStatus == pdPASS );
}

/**
 * This function should do the actual transmission of the packet. The packet is
 * contained in the pbuf that is passed to the function. This pbuf
 * might be chained.
 *
 * @param pxNetIf the lwip network interface structure for this etherpxNetIf
 * @param p the MAC packet to send (e.g. IP packet including MAC addresses and type)
 * @return ERR_OK if the packet could be sent
 *		 an err_t value if the packet couldn't be sent
 *
 * @note Returning ERR_MEM here if a DMA queue of your MAC is full can lead to
 *	   strange results. You might consider waiting for space in the DMA queue
 *	   to become availale since the stack doesn't retry to send a packet
 *	   dropped because of memory failure (except for the TCP timers).
 */

static err_t prvLowLevelOutput( struct netif *pxNetIf, struct pbuf *p )
{

	/* This is taken from lwIP example code and therefore does not conform
	to the FreeRTOS coding standard. */

struct pbuf *q;
static unsigned char ucBuffer[ 1520 ] __attribute__((aligned(32)));
unsigned char *pucBuffer = ucBuffer;
unsigned char *pucChar;
struct eth_hdr *pxHeader;
u16_t usTotalLength = p->tot_len - ETH_PAD_SIZE;
err_t xReturn = ERR_OK;
long x;

	( void ) pxNetIf;

	#if defined(LWIP_DEBUG) && LWIP_NETIF_TX_SINGLE_PBUF
		LWIP_ASSERT("p->next == NULL && p->len == p->tot_len", p->next == NULL && p->len == p->tot_len);
	#endif

	/* Initiate transfer. */
	if( p->len == p->tot_len ) 
	{
		/* No pbuf chain, don't have to copy -> faster. */
		pucBuffer = &( ( unsigned char * ) p->payload )[ ETH_PAD_SIZE ];
	} 
	else 
	{
		/* pbuf chain, copy into contiguous ucBuffer. */
		if( p->tot_len >= sizeof( ucBuffer ) )
		{
			LINK_STATS_INC( link.lenerr );
			LINK_STATS_INC( link.drop );
			snmp_inc_ifoutdiscards( pxNetIf );
			xReturn = ERR_BUF;
		}
		else
		{
			pucChar = ucBuffer;

			for( q = p; q != NULL; q = q->next )
			{
				/* Send the data from the pbuf to the interface, one pbuf at a
				time. The size of the data in each pbuf is kept in the ->len
				variable. */
				/* send data from(q->payload, q->len); */
				LWIP_DEBUGF( NETIF_DEBUG, ( "NETIF: send pucChar %p q->payload %p q->len %i q->next %p\n", pucChar, q->payload, ( int ) q->len, ( void* ) q->next ) );
				if( q == p )
				{
					memcpy( pucChar, &( ( char * ) q->payload )[ ETH_PAD_SIZE ], q->len - ETH_PAD_SIZE );
					pucChar += q->len - ETH_PAD_SIZE;
				}
				else
				{
					memcpy( pucChar, q->payload, q->len );
					pucChar += q->len;
				}
			}
		}
	}

	if( xReturn == ERR_OK )
	{
		for( x = 0; x < netifMAX_TX_ATTEMPTS; x++ )
		{
			xReturn =  XEmacLite_Send( &xEMACInstance, pucBuffer, ( int ) usTotalLength );
			if( xReturn == XST_SUCCESS )
			{
				break;
			}
			else
			{
				vTaskDelay( netifTX_BUFFER_FREE_WAIT );
			}
		}

		if( xReturn != XST_SUCCESS )
		{
			LINK_STATS_INC( link.memerr );
			LINK_STATS_INC( link.drop );
			snmp_inc_ifoutdiscards( pxNetIf );
			xReturn = ERR_BUF;
		}
		else
		{
			LINK_STATS_INC( link.xmit );
			snmp_add_ifoutoctets( pxNetIf, usTotalLength );
			pxHeader = ( struct eth_hdr * )p->payload;

			if( ( pxHeader->dest.addr[ 0 ] & 1 ) != 0 ) 
			{
				/* broadcast or multicast packet*/
				snmp_inc_ifoutnucastpkts( pxNetIf );
			} 
			else 
			{
				/* unicast packet */
				snmp_inc_ifoutucastpkts( pxNetIf );
			}
		}
	}

	return xReturn;
}

/**
 * Should allocate a pbuf and transfer the bytes of the incoming
 * packet from the interface into the pbuf.
 *
 * @param pxNetIf the lwip network interface structure for this etherpxNetIf
 * @return a pbuf filled with the received packet (including MAC header)
 *		 NULL on memory error
 */
static struct pbuf *prvLowLevelInput( const unsigned char * const pucInputData, unsigned short usDataLength )
{
struct pbuf *p = NULL, *q;

	if( usDataLength > 0U )
	{
		#if ETH_PAD_SIZE
			len += ETH_PAD_SIZE; /* allow room for Ethernet padding */
		#endif

		/* We allocate a pbuf chain of pbufs from the pool. */
		p = pbuf_alloc( PBUF_RAW, usDataLength, PBUF_POOL );
  
		if( p != NULL ) 
		{
			#if ETH_PAD_SIZE
				pbuf_header( p, -ETH_PAD_SIZE ); /* drop the padding word */
			#endif

			/* We iterate over the pbuf chain until we have read the entire
			* packet into the pbuf. */
			usDataLength = 0U;
			for( q = p; q != NULL; q = q->next ) 
			{
				/* Read enough bytes to fill this pbuf in the chain. The
				* available data in the pbuf is given by the q->len
				* variable.
				* This does not necessarily have to be a memcpy, you can also preallocate
				* pbufs for a DMA-enabled MAC and after receiving truncate it to the
				* actually received size. In this case, ensure the usTotalLength member of the
				* pbuf is the sum of the chained pbuf len members.
				*/
				memcpy( q->payload, &( pucInputData[ usDataLength ] ), q->len );
				usDataLength += q->len;
			}

			#if ETH_PAD_SIZE
				pbuf_header( p, ETH_PAD_SIZE ); /* reclaim the padding word */
			#endif

			LINK_STATS_INC(link.recv);
		}
	}

	return p;  
}

/**
 * Should be called at the beginning of the program to set up the
 * network interface. It calls the function prvLowLevelInit() to do the
 * actual setup of the hardware.
 *
 * This function should be passed as a parameter to pxNetIf_add().
 *
 * @param pxNetIf the lwip network interface structure for this etherpxNetIf
 * @return ERR_OK if the loopif is initialized
 *		 ERR_MEM if private data couldn't be allocated
 *		 any other err_t on error
 */
err_t ethernetif_init( struct netif *pxNetIf )
{
err_t xReturn = ERR_OK;

	/* This is taken from lwIP example code and therefore does not conform
	to the FreeRTOS coding standard. */
	
struct xEthernetIf *pxEthernetIf;

	LWIP_ASSERT( "pxNetIf != NULL", ( pxNetIf != NULL ) );
	
	pxEthernetIf = mem_malloc( sizeof( struct xEthernetIf ) );
	if( pxEthernetIf == NULL ) 
	{
		LWIP_DEBUGF(NETIF_DEBUG, ( "ethernetif_init: out of memory\n" ) );
		xReturn = ERR_MEM;
	}
	else
	{
		#if LWIP_NETIF_HOSTNAME
		{
			/* Initialize interface hostname */
			pxNetIf->hostname = "lwip";
		}
		#endif /* LWIP_NETIF_HOSTNAME */

		pxNetIf->state = pxEthernetIf;
		pxNetIf->name[ 0 ] = IFNAME0;
		pxNetIf->name[ 1 ] = IFNAME1;

		/* We directly use etharp_output() here to save a function call.
		* You can instead declare your own function an call etharp_output()
		* from it if you have to do some checks before sending (e.g. if link
		* is available...) */
		pxNetIf->output = etharp_output;
		pxNetIf->flags = NETIF_FLAG_BROADCAST | NETIF_FLAG_ETHARP | NETIF_FLAG_IGMP;
		pxNetIf->hwaddr_len = ETHARP_HWADDR_LEN;
		pxNetIf->mtu = netifMAX_MTU;
		pxNetIf->linkoutput = prvLowLevelOutput;

		pxEthernetIf->ethaddr = ( struct eth_addr * ) &( pxNetIf->hwaddr[ 0 ] );

		/* initialize the hardware */
		prvLowLevelInit( pxNetIf );
	}

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

static void prvRxHandler( void *pvNetIf )
{
	/* This is taken from lwIP example code and therefore does not conform
	to the FreeRTOS coding standard. */

struct eth_hdr *pxHeader;
struct pbuf *p;
unsigned short usInputLength;
static unsigned char ucBuffer[ 1520 ] __attribute__((aligned(32)));
extern portBASE_TYPE xInsideISR;
struct netif *pxNetIf = ( struct netif * ) pvNetIf;

	XIntc_AckIntr( XPAR_ETHERNET_LITE_BASEADDR, XPAR_ETHERNET_LITE_IP2INTC_IRPT_MASK );

	/* Ensure the pbuf handling functions don't attempt to use critical
	sections. */
	xInsideISR++;

	usInputLength = ( long ) XEmacLite_Recv( &xEMACInstance, ucBuffer );

	/* move received packet into a new pbuf */
	p = prvLowLevelInput( ucBuffer, usInputLength );

	/* no packet could be read, silently ignore this */
	if( p != NULL )
	{
		/* points to packet payload, which starts with an Ethernet header */
		pxHeader = p->payload;

		switch( htons( pxHeader->type ) )
		{
			/* IP or ARP packet? */
			case ETHTYPE_IP:
			case ETHTYPE_ARP:
								/* full packet send to tcpip_thread to process */
								if( pxNetIf->input( p, pxNetIf ) != ERR_OK )
								{
									LWIP_DEBUGF(NETIF_DEBUG, ( "ethernetif_input: IP input error\n" ) );
									pbuf_free(p);
									p = NULL;
								}
								break;

			default:
								pbuf_free( p );
								p = NULL;
			break;
		}
	}

	xInsideISR--;
}
/*-----------------------------------------------------------*/

static void prvTxHandler( void *pvUnused )
{
	( void ) pvUnused;
	XIntc_AckIntr( XPAR_ETHERNET_LITE_BASEADDR, XPAR_ETHERNET_LITE_IP2INTC_IRPT_MASK );
}




