fec_mpc52xx.c

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/*
 * Driver for the MPC5200 Fast Ethernet Controller
 *
 * Originally written by Dale Farnsworth <[email protected]> and
 * now maintained by Sylvain Munaut <[email protected]>
 *
 * Copyright (C) 2007  Domen Puncer, Telargo, Inc.
 * Copyright (C) 2007  Sylvain Munaut <[email protected]>
 * Copyright (C) 2003-2004  MontaVista, Software, Inc.
 *
 * This file is licensed under the terms of the GNU General Public License
 * version 2. This program is licensed "as is" without any warranty of any
 * kind, whether express or implied.
 *
 */

#include <linux/dma-mapping.h>
#include <linux/module.h>

#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/crc32.h>
#include <linux/hardirq.h>
#include <linux/delay.h>
#include <linux/of_device.h>
#include <linux/of_mdio.h>
#include <linux/of_platform.h>

#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/skbuff.h>

#include <asm/io.h>
#include <asm/delay.h>
#include <asm/mpc52xx.h>

#include <sysdev/bestcomm/bestcomm.h>
#include <sysdev/bestcomm/fec.h>

#include "fec_mpc52xx.h"

#define DRIVER_NAME "mpc52xx-fec"

/* Private driver data structure */
struct mpc52xx_fec_priv {
    struct net_device *ndev;
    int duplex;
    int speed;
    int r_irq;
    int t_irq;
    struct mpc52xx_fec __iomem *fec;
    struct bcom_task *rx_dmatsk;
    struct bcom_task *tx_dmatsk;
    spinlock_t lock;
    int msg_enable;

    /* MDIO link details */
    unsigned int mdio_speed;
    struct device_node *phy_node;
    struct phy_device *phydev;
    enum phy_state link;
    int seven_wire_mode;
};


static irqreturn_t mpc52xx_fec_interrupt(int, void *);
static irqreturn_t mpc52xx_fec_rx_interrupt(int, void *);
static irqreturn_t mpc52xx_fec_tx_interrupt(int, void *);
static void mpc52xx_fec_stop(struct net_device *dev);
static void mpc52xx_fec_start(struct net_device *dev);
static void mpc52xx_fec_reset(struct net_device *dev);

static u8 mpc52xx_fec_mac_addr[6];
module_param_array_named(mac, mpc52xx_fec_mac_addr, byte, NULL, 0);
MODULE_PARM_DESC(mac, "six hex digits, ie. 0x1,0x2,0xc0,0x01,0xba,0xbe");

#define MPC52xx_MESSAGES_DEFAULT ( NETIF_MSG_DRV | NETIF_MSG_PROBE | \
        NETIF_MSG_LINK | NETIF_MSG_IFDOWN | NETIF_MSG_IFUP)
static int debug = -1;  /* the above default */
module_param(debug, int, 0);
MODULE_PARM_DESC(debug, "debugging messages level");

static void mpc52xx_fec_tx_timeout(struct net_device *dev)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);
    unsigned long flags;

    dev_warn(&dev->dev, "transmit timed out\n");

    spin_lock_irqsave(&priv->lock, flags);
    mpc52xx_fec_reset(dev);
    dev->stats.tx_errors++;
    spin_unlock_irqrestore(&priv->lock, flags);

    netif_wake_queue(dev);
}

static void mpc52xx_fec_set_paddr(struct net_device *dev, u8 *mac)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);
    struct mpc52xx_fec __iomem *fec = priv->fec;

    out_be32(&fec->paddr1, *(u32 *)(&mac[0]));
    out_be32(&fec->paddr2, (*(u16 *)(&mac[4]) << 16) | FEC_PADDR2_TYPE);
}

static void mpc52xx_fec_get_paddr(struct net_device *dev, u8 *mac)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);
    struct mpc52xx_fec __iomem *fec = priv->fec;

    *(u32 *)(&mac[0]) = in_be32(&fec->paddr1);
    *(u16 *)(&mac[4]) = in_be32(&fec->paddr2) >> 16;
}

static int mpc52xx_fec_set_mac_address(struct net_device *dev, void *addr)
{
    struct sockaddr *sock = addr;

    memcpy(dev->dev_addr, sock->sa_data, dev->addr_len);

    mpc52xx_fec_set_paddr(dev, sock->sa_data);
    return 0;
}

static void mpc52xx_fec_free_rx_buffers(struct net_device *dev, struct bcom_task *s)
{
    while (!bcom_queue_empty(s)) {
        struct bcom_fec_bd *bd;
        struct sk_buff *skb;

        skb = bcom_retrieve_buffer(s, NULL, (struct bcom_bd **)&bd);
        dma_unmap_single(dev->dev.parent, bd->skb_pa, skb->len,
                 DMA_FROM_DEVICE);
        kfree_skb(skb);
    }
}

static void
mpc52xx_fec_rx_submit(struct net_device *dev, struct sk_buff *rskb)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);
    struct bcom_fec_bd *bd;

    bd = (struct bcom_fec_bd *) bcom_prepare_next_buffer(priv->rx_dmatsk);
    bd->status = FEC_RX_BUFFER_SIZE;
    bd->skb_pa = dma_map_single(dev->dev.parent, rskb->data,
                    FEC_RX_BUFFER_SIZE, DMA_FROM_DEVICE);
    bcom_submit_next_buffer(priv->rx_dmatsk, rskb);
}

static int mpc52xx_fec_alloc_rx_buffers(struct net_device *dev, struct bcom_task *rxtsk)
{
    struct sk_buff *skb;

    while (!bcom_queue_full(rxtsk)) {
        skb = netdev_alloc_skb(dev, FEC_RX_BUFFER_SIZE);
        if (!skb)
            return -EAGAIN;

        /* zero out the initial receive buffers to aid debugging */
        memset(skb->data, 0, FEC_RX_BUFFER_SIZE);
        mpc52xx_fec_rx_submit(dev, skb);
    }
    return 0;
}

/* based on generic_adjust_link from fs_enet-main.c */
static void mpc52xx_fec_adjust_link(struct net_device *dev)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);
    struct phy_device *phydev = priv->phydev;
    int new_state = 0;

    if (phydev->link != PHY_DOWN) {
        if (phydev->duplex != priv->duplex) {
            struct mpc52xx_fec __iomem *fec = priv->fec;
            u32 rcntrl;
            u32 tcntrl;

            new_state = 1;
            priv->duplex = phydev->duplex;

            rcntrl = in_be32(&fec->r_cntrl);
            tcntrl = in_be32(&fec->x_cntrl);

            rcntrl &= ~FEC_RCNTRL_DRT;
            tcntrl &= ~FEC_TCNTRL_FDEN;
            if (phydev->duplex == DUPLEX_FULL)
                tcntrl |= FEC_TCNTRL_FDEN;  /* FD enable */
            else
                rcntrl |= FEC_RCNTRL_DRT;   /* disable Rx on Tx (HD) */

            out_be32(&fec->r_cntrl, rcntrl);
            out_be32(&fec->x_cntrl, tcntrl);
        }

        if (phydev->speed != priv->speed) {
            new_state = 1;
            priv->speed = phydev->speed;
        }

        if (priv->link == PHY_DOWN) {
            new_state = 1;
            priv->link = phydev->link;
        }

    } else if (priv->link) {
        new_state = 1;
        priv->link = PHY_DOWN;
        priv->speed = 0;
        priv->duplex = -1;
    }

    if (new_state && netif_msg_link(priv))
        phy_print_status(phydev);
}

static int mpc52xx_fec_open(struct net_device *dev)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);
    int err = -EBUSY;

    if (priv->phy_node) {
        priv->phydev = of_phy_connect(priv->ndev, priv->phy_node,
                          mpc52xx_fec_adjust_link, 0, 0);
        if (!priv->phydev) {
            dev_err(&dev->dev, "of_phy_connect failed\n");
            return -ENODEV;
        }
        phy_start(priv->phydev);
    }

    if (request_irq(dev->irq, mpc52xx_fec_interrupt, IRQF_SHARED,
                    DRIVER_NAME "_ctrl", dev)) {
        dev_err(&dev->dev, "ctrl interrupt request failed\n");
        goto free_phy;
    }
    if (request_irq(priv->r_irq, mpc52xx_fec_rx_interrupt, 0,
                    DRIVER_NAME "_rx", dev)) {
        dev_err(&dev->dev, "rx interrupt request failed\n");
        goto free_ctrl_irq;
    }
    if (request_irq(priv->t_irq, mpc52xx_fec_tx_interrupt, 0,
                    DRIVER_NAME "_tx", dev)) {
        dev_err(&dev->dev, "tx interrupt request failed\n");
        goto free_2irqs;
    }

    bcom_fec_rx_reset(priv->rx_dmatsk);
    bcom_fec_tx_reset(priv->tx_dmatsk);

    err = mpc52xx_fec_alloc_rx_buffers(dev, priv->rx_dmatsk);
    if (err) {
        dev_err(&dev->dev, "mpc52xx_fec_alloc_rx_buffers failed\n");
        goto free_irqs;
    }

    bcom_enable(priv->rx_dmatsk);
    bcom_enable(priv->tx_dmatsk);

    mpc52xx_fec_start(dev);

    netif_start_queue(dev);

    return 0;

 free_irqs:
    free_irq(priv->t_irq, dev);
 free_2irqs:
    free_irq(priv->r_irq, dev);
 free_ctrl_irq:
    free_irq(dev->irq, dev);
 free_phy:
    if (priv->phydev) {
        phy_stop(priv->phydev);
        phy_disconnect(priv->phydev);
        priv->phydev = NULL;
    }

    return err;
}

static int mpc52xx_fec_close(struct net_device *dev)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);

    netif_stop_queue(dev);

    mpc52xx_fec_stop(dev);

    mpc52xx_fec_free_rx_buffers(dev, priv->rx_dmatsk);

    free_irq(dev->irq, dev);
    free_irq(priv->r_irq, dev);
    free_irq(priv->t_irq, dev);

    if (priv->phydev) {
        /* power down phy */
        phy_stop(priv->phydev);
        phy_disconnect(priv->phydev);
        priv->phydev = NULL;
    }

    return 0;
}

/* This will only be invoked if your driver is _not_ in XOFF state.
 * What this means is that you need not check it, and that this
 * invariant will hold if you make sure that the netif_*_queue()
 * calls are done at the proper times.
 */
static int mpc52xx_fec_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);
    struct bcom_fec_bd *bd;
    unsigned long flags;

    if (bcom_queue_full(priv->tx_dmatsk)) {
        if (net_ratelimit())
            dev_err(&dev->dev, "transmit queue overrun\n");
        return NETDEV_TX_BUSY;
    }

    spin_lock_irqsave(&priv->lock, flags);

    bd = (struct bcom_fec_bd *)
        bcom_prepare_next_buffer(priv->tx_dmatsk);

    bd->status = skb->len | BCOM_FEC_TX_BD_TFD | BCOM_FEC_TX_BD_TC;
    bd->skb_pa = dma_map_single(dev->dev.parent, skb->data, skb->len,
                    DMA_TO_DEVICE);

    skb_tx_timestamp(skb);
    bcom_submit_next_buffer(priv->tx_dmatsk, skb);
    spin_unlock_irqrestore(&priv->lock, flags);

    if (bcom_queue_full(priv->tx_dmatsk)) {
        netif_stop_queue(dev);
    }

    return NETDEV_TX_OK;
}

#ifdef CONFIG_NET_POLL_CONTROLLER
static void mpc52xx_fec_poll_controller(struct net_device *dev)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);

    disable_irq(priv->t_irq);
    mpc52xx_fec_tx_interrupt(priv->t_irq, dev);
    enable_irq(priv->t_irq);
    disable_irq(priv->r_irq);
    mpc52xx_fec_rx_interrupt(priv->r_irq, dev);
    enable_irq(priv->r_irq);
}
#endif


/* This handles BestComm transmit task interrupts
 */
static irqreturn_t mpc52xx_fec_tx_interrupt(int irq, void *dev_id)
{
    struct net_device *dev = dev_id;
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);

    spin_lock(&priv->lock);
    while (bcom_buffer_done(priv->tx_dmatsk)) {
        struct sk_buff *skb;
        struct bcom_fec_bd *bd;
        skb = bcom_retrieve_buffer(priv->tx_dmatsk, NULL,
                (struct bcom_bd **)&bd);
        dma_unmap_single(dev->dev.parent, bd->skb_pa, skb->len,
                 DMA_TO_DEVICE);

        dev_kfree_skb_irq(skb);
    }
    spin_unlock(&priv->lock);

    netif_wake_queue(dev);

    return IRQ_HANDLED;
}

static irqreturn_t mpc52xx_fec_rx_interrupt(int irq, void *dev_id)
{
    struct net_device *dev = dev_id;
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);
    struct sk_buff *rskb; /* received sk_buff */
    struct sk_buff *skb;  /* new sk_buff to enqueue in its place */
    struct bcom_fec_bd *bd;
    u32 status, physaddr;
    int length;

    spin_lock(&priv->lock);

    while (bcom_buffer_done(priv->rx_dmatsk)) {

        rskb = bcom_retrieve_buffer(priv->rx_dmatsk, &status,
                        (struct bcom_bd **)&bd);
        physaddr = bd->skb_pa;

        /* Test for errors in received frame */
        if (status & BCOM_FEC_RX_BD_ERRORS) {
            /* Drop packet and reuse the buffer */
            mpc52xx_fec_rx_submit(dev, rskb);
            dev->stats.rx_dropped++;
            continue;
        }

        /* skbs are allocated on open, so now we allocate a new one,
         * and remove the old (with the packet) */
        skb = netdev_alloc_skb(dev, FEC_RX_BUFFER_SIZE);
        if (!skb) {
            /* Can't get a new one : reuse the same & drop pkt */
            dev_notice(&dev->dev, "Low memory - dropped packet.\n");
            mpc52xx_fec_rx_submit(dev, rskb);
            dev->stats.rx_dropped++;
            continue;
        }

        /* Enqueue the new sk_buff back on the hardware */
        mpc52xx_fec_rx_submit(dev, skb);

        /* Process the received skb - Drop the spin lock while
         * calling into the network stack */
        spin_unlock(&priv->lock);

        dma_unmap_single(dev->dev.parent, physaddr, rskb->len,
                 DMA_FROM_DEVICE);
        length = status & BCOM_FEC_RX_BD_LEN_MASK;
        skb_put(rskb, length - 4);  /* length without CRC32 */
        rskb->protocol = eth_type_trans(rskb, dev);
        if (!skb_defer_rx_timestamp(rskb))
            netif_rx(rskb);

        spin_lock(&priv->lock);
    }

    spin_unlock(&priv->lock);

    return IRQ_HANDLED;
}

static irqreturn_t mpc52xx_fec_interrupt(int irq, void *dev_id)
{
    struct net_device *dev = dev_id;
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);
    struct mpc52xx_fec __iomem *fec = priv->fec;
    u32 ievent;

    ievent = in_be32(&fec->ievent);

    ievent &= ~FEC_IEVENT_MII;  /* mii is handled separately */
    if (!ievent)
        return IRQ_NONE;

    out_be32(&fec->ievent, ievent);     /* clear pending events */

    /* on fifo error, soft-reset fec */
    if (ievent & (FEC_IEVENT_RFIFO_ERROR | FEC_IEVENT_XFIFO_ERROR)) {

        if (net_ratelimit() && (ievent & FEC_IEVENT_RFIFO_ERROR))
            dev_warn(&dev->dev, "FEC_IEVENT_RFIFO_ERROR\n");
        if (net_ratelimit() && (ievent & FEC_IEVENT_XFIFO_ERROR))
            dev_warn(&dev->dev, "FEC_IEVENT_XFIFO_ERROR\n");

        spin_lock(&priv->lock);
        mpc52xx_fec_reset(dev);
        spin_unlock(&priv->lock);

        return IRQ_HANDLED;
    }

    if (ievent & ~FEC_IEVENT_TFINT)
        dev_dbg(&dev->dev, "ievent: %08x\n", ievent);

    return IRQ_HANDLED;
}

/*
 * Get the current statistics.
 * This may be called with the card open or closed.
 */
static struct net_device_stats *mpc52xx_fec_get_stats(struct net_device *dev)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);
    struct net_device_stats *stats = &dev->stats;
    struct mpc52xx_fec __iomem *fec = priv->fec;

    stats->rx_bytes = in_be32(&fec->rmon_r_octets);
    stats->rx_packets = in_be32(&fec->rmon_r_packets);
    stats->rx_errors = in_be32(&fec->rmon_r_crc_align) +
        in_be32(&fec->rmon_r_undersize) +
        in_be32(&fec->rmon_r_oversize) +
        in_be32(&fec->rmon_r_frag) +
        in_be32(&fec->rmon_r_jab);

    stats->tx_bytes = in_be32(&fec->rmon_t_octets);
    stats->tx_packets = in_be32(&fec->rmon_t_packets);
    stats->tx_errors = in_be32(&fec->rmon_t_crc_align) +
        in_be32(&fec->rmon_t_undersize) +
        in_be32(&fec->rmon_t_oversize) +
        in_be32(&fec->rmon_t_frag) +
        in_be32(&fec->rmon_t_jab);

    stats->multicast = in_be32(&fec->rmon_r_mc_pkt);
    stats->collisions = in_be32(&fec->rmon_t_col);

    /* detailed rx_errors: */
    stats->rx_length_errors = in_be32(&fec->rmon_r_undersize)
                    + in_be32(&fec->rmon_r_oversize)
                    + in_be32(&fec->rmon_r_frag)
                    + in_be32(&fec->rmon_r_jab);
    stats->rx_over_errors = in_be32(&fec->r_macerr);
    stats->rx_crc_errors = in_be32(&fec->ieee_r_crc);
    stats->rx_frame_errors = in_be32(&fec->ieee_r_align);
    stats->rx_fifo_errors = in_be32(&fec->rmon_r_drop);
    stats->rx_missed_errors = in_be32(&fec->rmon_r_drop);

    /* detailed tx_errors: */
    stats->tx_aborted_errors = 0;
    stats->tx_carrier_errors = in_be32(&fec->ieee_t_cserr);
    stats->tx_fifo_errors = in_be32(&fec->rmon_t_drop);
    stats->tx_heartbeat_errors = in_be32(&fec->ieee_t_sqe);
    stats->tx_window_errors = in_be32(&fec->ieee_t_lcol);

    return stats;
}

/*
 * Read MIB counters in order to reset them,
 * then zero all the stats fields in memory
 */
static void mpc52xx_fec_reset_stats(struct net_device *dev)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);
    struct mpc52xx_fec __iomem *fec = priv->fec;

    out_be32(&fec->mib_control, FEC_MIB_DISABLE);
    memset_io(&fec->rmon_t_drop, 0,
           offsetof(struct mpc52xx_fec, reserved10) -
           offsetof(struct mpc52xx_fec, rmon_t_drop));
    out_be32(&fec->mib_control, 0);

    memset(&dev->stats, 0, sizeof(dev->stats));
}

/*
 * Set or clear the multicast filter for this adaptor.
 */
static void mpc52xx_fec_set_multicast_list(struct net_device *dev)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);
    struct mpc52xx_fec __iomem *fec = priv->fec;
    u32 rx_control;

    rx_control = in_be32(&fec->r_cntrl);

    if (dev->flags & IFF_PROMISC) {
        rx_control |= FEC_RCNTRL_PROM;
        out_be32(&fec->r_cntrl, rx_control);
    } else {
        rx_control &= ~FEC_RCNTRL_PROM;
        out_be32(&fec->r_cntrl, rx_control);

        if (dev->flags & IFF_ALLMULTI) {
            out_be32(&fec->gaddr1, 0xffffffff);
            out_be32(&fec->gaddr2, 0xffffffff);
        } else {
            u32 crc;
            struct netdev_hw_addr *ha;
            u32 gaddr1 = 0x00000000;
            u32 gaddr2 = 0x00000000;

            netdev_for_each_mc_addr(ha, dev) {
                crc = ether_crc_le(6, ha->addr) >> 26;
                if (crc >= 32)
                    gaddr1 |= 1 << (crc-32);
                else
                    gaddr2 |= 1 << crc;
            }
            out_be32(&fec->gaddr1, gaddr1);
            out_be32(&fec->gaddr2, gaddr2);
        }
    }
}

static void mpc52xx_fec_hw_init(struct net_device *dev)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);
    struct mpc52xx_fec __iomem *fec = priv->fec;
    int i;

    /* Whack a reset.  We should wait for this. */
    out_be32(&fec->ecntrl, FEC_ECNTRL_RESET);
    for (i = 0; i < FEC_RESET_DELAY; ++i) {
        if ((in_be32(&fec->ecntrl) & FEC_ECNTRL_RESET) == 0)
            break;
        udelay(1);
    }
    if (i == FEC_RESET_DELAY)
        dev_err(&dev->dev, "FEC Reset timeout!\n");

    /* set pause to 0x20 frames */
    out_be32(&fec->op_pause, FEC_OP_PAUSE_OPCODE | 0x20);

    /* high service request will be deasserted when there's < 7 bytes in fifo
     * low service request will be deasserted when there's < 4*7 bytes in fifo
     */
    out_be32(&fec->rfifo_cntrl, FEC_FIFO_CNTRL_FRAME | FEC_FIFO_CNTRL_LTG_7);
    out_be32(&fec->tfifo_cntrl, FEC_FIFO_CNTRL_FRAME | FEC_FIFO_CNTRL_LTG_7);

    /* alarm when <= x bytes in FIFO */
    out_be32(&fec->rfifo_alarm, 0x0000030c);
    out_be32(&fec->tfifo_alarm, 0x00000100);

    /* begin transmittion when 256 bytes are in FIFO (or EOF or FIFO full) */
    out_be32(&fec->x_wmrk, FEC_FIFO_WMRK_256B);

    /* enable crc generation */
    out_be32(&fec->xmit_fsm, FEC_XMIT_FSM_APPEND_CRC | FEC_XMIT_FSM_ENABLE_CRC);
    out_be32(&fec->iaddr1, 0x00000000); /* No individual filter */
    out_be32(&fec->iaddr2, 0x00000000); /* No individual filter */

    /* set phy speed.
     * this can't be done in phy driver, since it needs to be called
     * before fec stuff (even on resume) */
    out_be32(&fec->mii_speed, priv->mdio_speed);
}

static void mpc52xx_fec_start(struct net_device *dev)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);
    struct mpc52xx_fec __iomem *fec = priv->fec;
    u32 rcntrl;
    u32 tcntrl;
    u32 tmp;

    /* clear sticky error bits */
    tmp = FEC_FIFO_STATUS_ERR | FEC_FIFO_STATUS_UF | FEC_FIFO_STATUS_OF;
    out_be32(&fec->rfifo_status, in_be32(&fec->rfifo_status) & tmp);
    out_be32(&fec->tfifo_status, in_be32(&fec->tfifo_status) & tmp);

    /* FIFOs will reset on mpc52xx_fec_enable */
    out_be32(&fec->reset_cntrl, FEC_RESET_CNTRL_ENABLE_IS_RESET);

    /* Set station address. */
    mpc52xx_fec_set_paddr(dev, dev->dev_addr);

    mpc52xx_fec_set_multicast_list(dev);

    /* set max frame len, enable flow control, select mii mode */
    rcntrl = FEC_RX_BUFFER_SIZE << 16;  /* max frame length */
    rcntrl |= FEC_RCNTRL_FCE;

    if (!priv->seven_wire_mode)
        rcntrl |= FEC_RCNTRL_MII_MODE;

    if (priv->duplex == DUPLEX_FULL)
        tcntrl = FEC_TCNTRL_FDEN;   /* FD enable */
    else {
        rcntrl |= FEC_RCNTRL_DRT;   /* disable Rx on Tx (HD) */
        tcntrl = 0;
    }
    out_be32(&fec->r_cntrl, rcntrl);
    out_be32(&fec->x_cntrl, tcntrl);

    /* Clear any outstanding interrupt. */
    out_be32(&fec->ievent, 0xffffffff);

    /* Enable interrupts we wish to service. */
    out_be32(&fec->imask, FEC_IMASK_ENABLE);

    /* And last, enable the transmit and receive processing. */
    out_be32(&fec->ecntrl, FEC_ECNTRL_ETHER_EN);
    out_be32(&fec->r_des_active, 0x01000000);
}

static void mpc52xx_fec_stop(struct net_device *dev)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);
    struct mpc52xx_fec __iomem *fec = priv->fec;
    unsigned long timeout;

    /* disable all interrupts */
    out_be32(&fec->imask, 0);

    /* Disable the rx task. */
    bcom_disable(priv->rx_dmatsk);

    /* Wait for tx queue to drain, but only if we're in process context */
    if (!in_interrupt()) {
        timeout = jiffies + msecs_to_jiffies(2000);
        while (time_before(jiffies, timeout) &&
                !bcom_queue_empty(priv->tx_dmatsk))
            msleep(100);

        if (time_after_eq(jiffies, timeout))
            dev_err(&dev->dev, "queues didn't drain\n");
#if 1
        if (time_after_eq(jiffies, timeout)) {
            dev_err(&dev->dev, "  tx: index: %i, outdex: %i\n",
                    priv->tx_dmatsk->index,
                    priv->tx_dmatsk->outdex);
            dev_err(&dev->dev, "  rx: index: %i, outdex: %i\n",
                    priv->rx_dmatsk->index,
                    priv->rx_dmatsk->outdex);
        }
#endif
    }

    bcom_disable(priv->tx_dmatsk);

    /* Stop FEC */
    out_be32(&fec->ecntrl, in_be32(&fec->ecntrl) & ~FEC_ECNTRL_ETHER_EN);
}

/* reset fec and bestcomm tasks */
static void mpc52xx_fec_reset(struct net_device *dev)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);
    struct mpc52xx_fec __iomem *fec = priv->fec;

    mpc52xx_fec_stop(dev);

    out_be32(&fec->rfifo_status, in_be32(&fec->rfifo_status));
    out_be32(&fec->reset_cntrl, FEC_RESET_CNTRL_RESET_FIFO);

    mpc52xx_fec_free_rx_buffers(dev, priv->rx_dmatsk);

    mpc52xx_fec_hw_init(dev);

    bcom_fec_rx_reset(priv->rx_dmatsk);
    bcom_fec_tx_reset(priv->tx_dmatsk);

    mpc52xx_fec_alloc_rx_buffers(dev, priv->rx_dmatsk);

    bcom_enable(priv->rx_dmatsk);
    bcom_enable(priv->tx_dmatsk);

    mpc52xx_fec_start(dev);

    netif_wake_queue(dev);
}


/* ethtool interface */

static int mpc52xx_fec_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);

    if (!priv->phydev)
        return -ENODEV;

    return phy_ethtool_gset(priv->phydev, cmd);
}

static int mpc52xx_fec_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);

    if (!priv->phydev)
        return -ENODEV;

    return phy_ethtool_sset(priv->phydev, cmd);
}

static u32 mpc52xx_fec_get_msglevel(struct net_device *dev)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);
    return priv->msg_enable;
}

static void mpc52xx_fec_set_msglevel(struct net_device *dev, u32 level)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);
    priv->msg_enable = level;
}

static const struct ethtool_ops mpc52xx_fec_ethtool_ops = {
    .get_settings = mpc52xx_fec_get_settings,
    .set_settings = mpc52xx_fec_set_settings,
    .get_link = ethtool_op_get_link,
    .get_msglevel = mpc52xx_fec_get_msglevel,
    .set_msglevel = mpc52xx_fec_set_msglevel,
    .get_ts_info = ethtool_op_get_ts_info,
};


static int mpc52xx_fec_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
{
    struct mpc52xx_fec_priv *priv = netdev_priv(dev);

    if (!priv->phydev)
        return -ENOTSUPP;

    return phy_mii_ioctl(priv->phydev, rq, cmd);
}

static const struct net_device_ops mpc52xx_fec_netdev_ops = {
    .ndo_open = mpc52xx_fec_open,
    .ndo_stop = mpc52xx_fec_close,
    .ndo_start_xmit = mpc52xx_fec_start_xmit,
    .ndo_set_rx_mode = mpc52xx_fec_set_multicast_list,
    .ndo_set_mac_address = mpc52xx_fec_set_mac_address,
    .ndo_validate_addr = eth_validate_addr,
    .ndo_do_ioctl = mpc52xx_fec_ioctl,
    .ndo_change_mtu = eth_change_mtu,
    .ndo_tx_timeout = mpc52xx_fec_tx_timeout,
    .ndo_get_stats = mpc52xx_fec_get_stats,
#ifdef CONFIG_NET_POLL_CONTROLLER
    .ndo_poll_controller = mpc52xx_fec_poll_controller,
#endif
};

/* ======================================================================== */
/* OF Driver                                                                */
/* ======================================================================== */

static int __devinit mpc52xx_fec_probe(struct platform_device *op)
{
    int rv;
    struct net_device *ndev;
    struct mpc52xx_fec_priv *priv = NULL;
    struct resource mem;
    const u32 *prop;
    int prop_size;

    phys_addr_t rx_fifo;
    phys_addr_t tx_fifo;

    /* Get the ether ndev & it's private zone */
    ndev = alloc_etherdev(sizeof(struct mpc52xx_fec_priv));
    if (!ndev)
        return -ENOMEM;

    priv = netdev_priv(ndev);
    priv->ndev = ndev;

    /* Reserve FEC control zone */
    rv = of_address_to_resource(op->dev.of_node, 0, &mem);
    if (rv) {
        printk(KERN_ERR DRIVER_NAME ": "
                "Error while parsing device node resource\n" );
        goto err_netdev;
    }
    if (resource_size(&mem) < sizeof(struct mpc52xx_fec)) {
        printk(KERN_ERR DRIVER_NAME
               " - invalid resource size (%lx < %x), check mpc52xx_devices.c\n",
               (unsigned long)resource_size(&mem),
               sizeof(struct mpc52xx_fec));
        rv = -EINVAL;
        goto err_netdev;
    }

    if (!request_mem_region(mem.start, sizeof(struct mpc52xx_fec),
                DRIVER_NAME)) {
        rv = -EBUSY;
        goto err_netdev;
    }

    /* Init ether ndev with what we have */
    ndev->netdev_ops    = &mpc52xx_fec_netdev_ops;
    ndev->ethtool_ops   = &mpc52xx_fec_ethtool_ops;
    ndev->watchdog_timeo    = FEC_WATCHDOG_TIMEOUT;
    ndev->base_addr     = mem.start;
    SET_NETDEV_DEV(ndev, &op->dev);

    spin_lock_init(&priv->lock);

    /* ioremap the zones */
    priv->fec = ioremap(mem.start, sizeof(struct mpc52xx_fec));

    if (!priv->fec) {
        rv = -ENOMEM;
        goto err_mem_region;
    }

    /* Bestcomm init */
    rx_fifo = ndev->base_addr + offsetof(struct mpc52xx_fec, rfifo_data);
    tx_fifo = ndev->base_addr + offsetof(struct mpc52xx_fec, tfifo_data);

    priv->rx_dmatsk = bcom_fec_rx_init(FEC_RX_NUM_BD, rx_fifo, FEC_RX_BUFFER_SIZE);
    priv->tx_dmatsk = bcom_fec_tx_init(FEC_TX_NUM_BD, tx_fifo);

    if (!priv->rx_dmatsk || !priv->tx_dmatsk) {
        printk(KERN_ERR DRIVER_NAME ": Can not init SDMA tasks\n" );
        rv = -ENOMEM;
        goto err_rx_tx_dmatsk;
    }

    /* Get the IRQ we need one by one */
        /* Control */
    ndev->irq = irq_of_parse_and_map(op->dev.of_node, 0);

        /* RX */
    priv->r_irq = bcom_get_task_irq(priv->rx_dmatsk);

        /* TX */
    priv->t_irq = bcom_get_task_irq(priv->tx_dmatsk);

    /* MAC address init */
    if (!is_zero_ether_addr(mpc52xx_fec_mac_addr))
        memcpy(ndev->dev_addr, mpc52xx_fec_mac_addr, 6);
    else
        mpc52xx_fec_get_paddr(ndev, ndev->dev_addr);

    priv->msg_enable = netif_msg_init(debug, MPC52xx_MESSAGES_DEFAULT);

    /*
     * Link mode configuration
     */

    /* Start with safe defaults for link connection */
    priv->speed = 100;
    priv->duplex = DUPLEX_HALF;
    priv->mdio_speed = ((mpc5xxx_get_bus_frequency(op->dev.of_node) >> 20) / 5) << 1;

    /* The current speed preconfigures the speed of the MII link */
    prop = of_get_property(op->dev.of_node, "current-speed", &prop_size);
    if (prop && (prop_size >= sizeof(u32) * 2)) {
        priv->speed = prop[0];
        priv->duplex = prop[1] ? DUPLEX_FULL : DUPLEX_HALF;
    }

    /* If there is a phy handle, then get the PHY node */
    priv->phy_node = of_parse_phandle(op->dev.of_node, "phy-handle", 0);

    /* the 7-wire property means don't use MII mode */
    if (of_find_property(op->dev.of_node, "fsl,7-wire-mode", NULL)) {
        priv->seven_wire_mode = 1;
        dev_info(&ndev->dev, "using 7-wire PHY mode\n");
    }

    /* Hardware init */
    mpc52xx_fec_hw_init(ndev);
    mpc52xx_fec_reset_stats(ndev);

    rv = register_netdev(ndev);
    if (rv < 0)
        goto err_node;

    /* We're done ! */
    dev_set_drvdata(&op->dev, ndev);

    return 0;

err_node:
    of_node_put(priv->phy_node);
    irq_dispose_mapping(ndev->irq);
err_rx_tx_dmatsk:
    if (priv->rx_dmatsk)
        bcom_fec_rx_release(priv->rx_dmatsk);
    if (priv->tx_dmatsk)
        bcom_fec_tx_release(priv->tx_dmatsk);
    iounmap(priv->fec);
err_mem_region:
    release_mem_region(mem.start, sizeof(struct mpc52xx_fec));
err_netdev:
    free_netdev(ndev);

    return rv;
}

static int
mpc52xx_fec_remove(struct platform_device *op)
{
    struct net_device *ndev;
    struct mpc52xx_fec_priv *priv;

    ndev = dev_get_drvdata(&op->dev);
    priv = netdev_priv(ndev);

    unregister_netdev(ndev);

    if (priv->phy_node)
        of_node_put(priv->phy_node);
    priv->phy_node = NULL;

    irq_dispose_mapping(ndev->irq);

    bcom_fec_rx_release(priv->rx_dmatsk);
    bcom_fec_tx_release(priv->tx_dmatsk);

    iounmap(priv->fec);

    release_mem_region(ndev->base_addr, sizeof(struct mpc52xx_fec));

    free_netdev(ndev);

    dev_set_drvdata(&op->dev, NULL);
    return 0;
}

#ifdef CONFIG_PM
static int mpc52xx_fec_of_suspend(struct platform_device *op, pm_message_t state)
{
    struct net_device *dev = dev_get_drvdata(&op->dev);

    if (netif_running(dev))
        mpc52xx_fec_close(dev);

    return 0;
}

static int mpc52xx_fec_of_resume(struct platform_device *op)
{
    struct net_device *dev = dev_get_drvdata(&op->dev);

    mpc52xx_fec_hw_init(dev);
    mpc52xx_fec_reset_stats(dev);

    if (netif_running(dev))
        mpc52xx_fec_open(dev);

    return 0;
}
#endif

static struct of_device_id mpc52xx_fec_match[] = {
    { .compatible = "fsl,mpc5200b-fec", },
    { .compatible = "fsl,mpc5200-fec", },
    { .compatible = "mpc5200-fec", },
    { }
};

MODULE_DEVICE_TABLE(of, mpc52xx_fec_match);

static struct platform_driver mpc52xx_fec_driver = {
    .driver = {
        .name = DRIVER_NAME,
        .owner = THIS_MODULE,
        .of_match_table = mpc52xx_fec_match,
    },
    .probe      = mpc52xx_fec_probe,
    .remove     = mpc52xx_fec_remove,
#ifdef CONFIG_PM
    .suspend    = mpc52xx_fec_of_suspend,
    .resume     = mpc52xx_fec_of_resume,
#endif
};


/* ======================================================================== */
/* Module                                                                   */
/* ======================================================================== */

static int __init
mpc52xx_fec_init(void)
{
#ifdef CONFIG_FEC_MPC52xx_MDIO
    int ret;
    ret = platform_driver_register(&mpc52xx_fec_mdio_driver);
    if (ret) {
        printk(KERN_ERR DRIVER_NAME ": failed to register mdio driver\n");
        return ret;
    }
#endif
    return platform_driver_register(&mpc52xx_fec_driver);
}

static void __exit
mpc52xx_fec_exit(void)
{
    platform_driver_unregister(&mpc52xx_fec_driver);
#ifdef CONFIG_FEC_MPC52xx_MDIO
    platform_driver_unregister(&mpc52xx_fec_mdio_driver);
#endif
}


module_init(mpc52xx_fec_init);
module_exit(mpc52xx_fec_exit);

MODULE_LICENSE("GPL");
MODULE_AUTHOR("Dale Farnsworth");
MODULE_DESCRIPTION("Ethernet driver for the Freescale MPC52xx FEC");