/*
 * Copyright (c) 2006 Christian Walter
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 *    this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright notice,
 *    this list of conditions and the following disclaimer in the documentation
 *    and/or other materials provided with the distribution.
 * 3. The name of the author may not be used to endorse or promote products
 *    derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT
 * SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
 * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY
 * OF SUCH DAMAGE.
 *
 * Author: Christian Walter <wolti@sil.at>
 *
 * TODO:
 *  - Introduce another task create function in the sys_arch layer which allows
 *    for passing the stack size.
 *  - Avoid copying the buffers - this requires changeing the nbuf driver code
 *    to use the lwIP pbuf buffer implementation.
 *
 * File: $Id: fec.c,v 1.1 2006/08/30 23:18:07 wolti Exp $
 */

/* ------------------------ System includes ------------------------------- */
#include <stdlib.h>

/* ------------------------ Platform includes ----------------------------- */
#include "mcf5xxx.h"
#include "mcf523x.h"

#include "nbuf.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/debug.h"
#include "netif/etharp.h"

/* ------------------------ Defines --------------------------------------- */
#ifdef FEC_DEBUG
#define FEC_DEBUG_INIT \
    do \
    { \
        MCF_GPIO_PDDR_FECI2C = ( MCF_GPIO_PDDR_FECI2C_PDDR_FECI2C0 | \
                                 MCF_GPIO_PDDR_FECI2C_PDDR_FECI2C1 ); \
    } while( 0 )

#define FEC_DEBUG_RX_TIMING( x ) \
    do \
    { \
        if( x ) \
            MCF_GPIO_PPDSDR_FECI2C = MCF_GPIO_PDDR_FECI2C_PDDR_FECI2C0; \
        else \
            MCF_GPIO_PCLRR_FECI2C = ~( MCF_GPIO_PDDR_FECI2C_PDDR_FECI2C0 ); \
    } while( 0 )

#define FEC_DEBUG_TX_TIMING( x ) \
    do \
    { \
        if( x ) \
            MCF_GPIO_PPDSDR_FECI2C = MCF_GPIO_PDDR_FECI2C_PDDR_FECI2C1; \
        else \
            MCF_GPIO_PCLRR_FECI2C = ~( MCF_GPIO_PDDR_FECI2C_PDDR_FECI2C1 ); \
    } while( 0 )

#else
#define FEC_DEBUG               DBG_OFF
#define FEC_DEBUG_INIT
#define FEC_DEBUG_RX_TIMING( x )
#define FEC_DEBUG_TX_TIMING( x )
#endif

#define MCF_FEC_INT_LEVEL       ( 6 )
#define MCF_FEC_INT_PRIORITY    ( 0 )
#define MCF_FEC_VEC_RXF         ( 64 + 27 )
#define MCF_FEC_MTU             ( 1518 )

#define ETH_ADDR_LEN            ( 6 )

#define TASK_PRIORITY           ( configMAX_PRIORITIES - 1 )

/* ------------------------ Type definitions ------------------------------ */
typedef struct
{
    struct netif   *netif;      /* lwIP network interface. */
    struct eth_addr *self;      /* MAC address of FEC interface. */
    sys_sem_t       tx_sem;     /* Control access to transmitter. */
    sys_sem_t       rx_sem;     /* Semaphore to signal receive thread. */
} mcf523xfec_if_t;

/* ------------------------ Static variables ------------------------------ */
static mcf523xfec_if_t *fecif_g;

/* ------------------------ Static functions ------------------------------ */
static err_t    mcf523xfec_output( struct netif *, struct pbuf *, struct ip_addr * );
static err_t    mcf523xfec_output_raw( struct netif *, struct pbuf * );

static void     mcf523xfec_reset( mcf523xfec_if_t * fecif );
static void     mcf523xfec_enable( mcf523xfec_if_t * fecif );
static void     mcf523xfec_disable( mcf523xfec_if_t * fecif );
static void     mcf523xfec_get_mac( mcf523xfec_if_t * fecif, struct eth_addr *mac );
static void     mcf523xfec_rx_irq( void );
static void     mcf523xfec_rx_task( void *arg );

static void     arp_timer( void *arg );
static void     eth_input( struct netif *netif, struct pbuf *p );

/* ------------------------ Start implementation -------------------------- */

static void
arp_timer( void *arg )
{
    ( void )arg;
    etharp_tmr(  );
    sys_timeout( ARP_TMR_INTERVAL, arp_timer, NULL );
}

err_t
mcf523xfec_output_raw( struct netif *netif, struct pbuf *p )
{
    err_t           res;
    nbuf_t         *pNBuf;
    mcf523xfec_if_t *fecif = netif->state;
    int             i;
    struct pbuf    *q;

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


    /* Test if we can handle such big frames. If not drop it. */
    if( p->tot_len > MCF_FEC_MTU )
    {
#if LINK_STATS
        lwip_stats.link.lenerr++;
#endif
        res = ERR_BUF;
    }
    /* Test if our network buffer scheme can handle a packet of this size. If
     * not drop it and return a memory error. */
    else if( p->tot_len > TX_BUFFER_SIZE )
    {
#ifdef LINK_STATS
        lwip_stats.link.memerr++;
#endif
        res = ERR_MEM;
    }
    /* Allocate a transmit buffer. If no buffer is available drop the frame. */
    else if( ( pNBuf = nbuf_tx_allocate(  ) ) == NULL )
    {
        LWIP_ASSERT( "mcf523xfec_output_raw: pNBuf != NULL\n", pNBuf != NULL );
#ifdef LINK_STATS
        lwip_stats.link.memerr++;
#endif
        res = ERR_MEM;
    }
    else
    {
        q = p;
        i = 0;
        do
        {
            memcpy( &pNBuf->data[i], q->payload, q->len );
            i += q->len;
        }
        while( ( q = q->next ) != NULL );
        pNBuf->length = p->tot_len;

        /* Set Frame ready for transmission. */
        pNBuf->status |= TX_BD_R;
        /* Mark the buffer as not in use so the FEC can take it. */
        nbuf_tx_release( pNBuf );
        /* Indicate that a new transmit buffer has been produced. */
        MCF_FEC_TDAR = 1;
#if LINK_STATS
        lwip_stats.link.xmit++;
#endif
        res = ERR_OK;
    }

    sys_sem_signal( fecif->tx_sem );
#if ETH_PAD_SIZE
    buf_header( p, ETH_PAD_SIZE );
#endif

    return res;
}

/* This function is called by the TCP/IP stack when an IP packet should be
 * sent. It uses the ethernet ARP module provided by lwIP to resolve the
 * destination MAC address. The ARP module will later call our low level
 * output function mcf523xfec_output_raw.
 */
err_t
mcf523xfec_output( struct netif * netif, struct pbuf * p, struct ip_addr * ipaddr )
{
    err_t           res;
    mcf523xfec_if_t *fecif = netif->state;

    FEC_DEBUG_TX_TIMING( 1 );
    /* Make sure only one thread is in this function. */
    sys_sem_wait( fecif->tx_sem );
    res = etharp_output( netif, ipaddr, p );
    FEC_DEBUG_TX_TIMING( 0 );
    return res;
}

void
mcf523xfec_rx_task( void *arg )
{
    mcf523xfec_if_t *fecif = arg;
    struct pbuf    *p, *q;
    nbuf_t         *pNBuf;
    uint8          *pPayLoad;

    do
    {
        sys_sem_wait( fecif->rx_sem );
        while( nbuf_rx_next_ready(  ) )
        {
            pNBuf = nbuf_rx_allocate(  );
            if( pNBuf != NULL )
            {
                LWIP_ASSERT( "mcf523xfec_rx_task: pNBuf->status & RX_BD_L ",
                             pNBuf->status & RX_BD_L );

                /* This flags indicate that the frame has been damaged. In
                 * this case we must update the link stats if enabled and
                 * remove the frame from the FEC. */
                if( pNBuf->status & ( RX_BD_LG | RX_BD_NO | RX_BD_CR | RX_BD_OV ) )
                {
#ifdef LINK_STATS
                    lwip_stats.link.drop++;
                    if( pNBuf->status & RX_BD_LG )
                    {
                        lwip_stats.link.lenerr++;
                    }
                    else if( pNBuf->status & ( RX_BD_NO | RX_BD_OV ) )
                    {
                        lwip_stats.link.err++;
                    }
                    else
                    {
                        lwip_stats.link.chkerr++;
                    }
#endif
                }
                else
                {
                    /* The frame must no be valid. Perform some checks to see if the FEC
                     * driver is working correctly.
                     */
                    LWIP_ASSERT( "mcf523xfec_rx_task: pNBuf->length != 0", pNBuf->length != 0 );
                    p = pbuf_alloc( PBUF_RAW, pNBuf->length, PBUF_POOL );
                    if( p != NULL )
                    {
#if ETH_PAD_SIZE
                        pbuf_header( p, -ETH_PAD_SIZE );
#endif
                        pPayLoad = pNBuf->data;
                        for( q = p; q != NULL; q = q->next )
                        {
                            memcpy( q->payload, pPayLoad, q->len );
                            pPayLoad += q->len;
                        }
#if ETH_PAD_SIZE
                        pbuf_header( p, ETH_PAD_SIZE );
#endif

                        /* Ethernet frame received. Handling it is not device
                         * dependent and therefore done in another function.
                         */