/*
 * Combined Ethernet driver for Motorola MPC8xx and MPC82xx.
 *
 * Copyright (c) 2003 Intracom S.A.
 *  by Pantelis Antoniou <panto@intracom.gr>
 *
 * 2005 (c) MontaVista Software, Inc.
 * Vitaly Bordug <vbordug@ru.mvista.com>
 *
 * Heavily based on original FEC driver by Dan Malek <dan@embeddededge.com>
 * and modifications by Joakim Tjernlund <joakim.tjernlund@lumentis.se>
 *
 * 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/module.h>
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/string.h>
#include <linux/ptrace.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
#include <linux/mii.h>
#include <linux/ethtool.h>
#include <linux/bitops.h>
#include <linux/fs.h>
#include <linux/platform_device.h>
#include <linux/phy.h>
#include <linux/of.h>
#include <linux/of_mdio.h>
#include <linux/of_platform.h>
#include <linux/of_gpio.h>
#include <linux/of_net.h>
#include <linux/pgtable.h>

#include <linux/vmalloc.h>
#include <asm/irq.h>
#include <linux/uaccess.h>

#include "fs_enet.h"

/*************************************************/

MODULE_AUTHOR("Pantelis Antoniou <panto@intracom.gr>");
MODULE_DESCRIPTION("Freescale Ethernet Driver");
MODULE_LICENSE("GPL");

static int fs_enet_debug = -1; /* -1 == use FS_ENET_DEF_MSG_ENABLE as value */
module_param(fs_enet_debug, int, 0);
MODULE_PARM_DESC(fs_enet_debug,
                 "Freescale bitmapped debugging message enable value");

#define RX_RING_SIZE    32
#define TX_RING_SIZE    64

#ifdef CONFIG_NET_POLL_CONTROLLER
static void fs_enet_netpoll(struct net_device *dev);
#endif

static void fs_set_multicast_list(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);

        (*fep->ops->set_multicast_list)(dev);
}

static void skb_align(struct sk_buff *skb, int align)
{
        int off = ((unsigned long)skb->data) & (align - 1);

        if (off)
                skb_reserve(skb, align - off);
}

/* NAPI function */
static int fs_enet_napi(struct napi_struct *napi, int budget)
{
        struct fs_enet_private *fep = container_of(napi, struct fs_enet_private, napi);
        struct net_device *dev = fep->ndev;
        const struct fs_platform_info *fpi = fep->fpi;
        cbd_t __iomem *bdp;
        struct sk_buff *skb, *skbn;
        int received = 0;
        u16 pkt_len, sc;
        int curidx;
        int dirtyidx, do_wake, do_restart;
        int tx_left = TX_RING_SIZE;

        spin_lock(&fep->tx_lock);
        bdp = fep->dirty_tx;

        /* clear status bits for napi*/
        (*fep->ops->napi_clear_event)(dev);

        do_wake = do_restart = 0;
        while (((sc = CBDR_SC(bdp)) & BD_ENET_TX_READY) == 0 && tx_left) {
                dirtyidx = bdp - fep->tx_bd_base;

                if (fep->tx_free == fep->tx_ring)
                        break;

                skb = fep->tx_skbuff[dirtyidx];

                /*
                 * Check for errors.
                 */
                if (sc & (BD_ENET_TX_HB | BD_ENET_TX_LC |
                          BD_ENET_TX_RL | BD_ENET_TX_UN | BD_ENET_TX_CSL)) {

                        if (sc & BD_ENET_TX_HB) /* No heartbeat */
                                dev->stats.tx_heartbeat_errors++;
                        if (sc & BD_ENET_TX_LC) /* Late collision */
                                dev->stats.tx_window_errors++;
                        if (sc & BD_ENET_TX_RL) /* Retrans limit */
                                dev->stats.tx_aborted_errors++;
                        if (sc & BD_ENET_TX_UN) /* Underrun */
                                dev->stats.tx_fifo_errors++;
                        if (sc & BD_ENET_TX_CSL)        /* Carrier lost */
                                dev->stats.tx_carrier_errors++;

                        if (sc & (BD_ENET_TX_LC | BD_ENET_TX_RL | BD_ENET_TX_UN)) {
                                dev->stats.tx_errors++;
                                do_restart = 1;
                        }
                } else
                        dev->stats.tx_packets++;

                if (sc & BD_ENET_TX_READY) {
                        dev_warn(fep->dev,
                                 "HEY! Enet xmit interrupt and TX_READY.\n");
                }

                /*
                 * Deferred means some collisions occurred during transmit,
                 * but we eventually sent the packet OK.
                 */
                if (sc & BD_ENET_TX_DEF)
                        dev->stats.collisions++;

                /* unmap */
                if (fep->mapped_as_page[dirtyidx])
                        dma_unmap_page(fep->dev, CBDR_BUFADDR(bdp),
                                       CBDR_DATLEN(bdp), DMA_TO_DEVICE);
                else
                        dma_unmap_single(fep->dev, CBDR_BUFADDR(bdp),
                                         CBDR_DATLEN(bdp), DMA_TO_DEVICE);

                /*
                 * Free the sk buffer associated with this last transmit.
                 */
                if (skb) {
                        dev_kfree_skb(skb);
                        fep->tx_skbuff[dirtyidx] = NULL;
                }

                /*
                 * Update pointer to next buffer descriptor to be transmitted.
                 */
                if ((sc & BD_ENET_TX_WRAP) == 0)
                        bdp++;
                else
                        bdp = fep->tx_bd_base;

                /*
                 * Since we have freed up a buffer, the ring is no longer
                 * full.
                 */
                if (++fep->tx_free == MAX_SKB_FRAGS)
                        do_wake = 1;
                tx_left--;
        }

        fep->dirty_tx = bdp;

        if (do_restart)
                (*fep->ops->tx_restart)(dev);

        spin_unlock(&fep->tx_lock);

        if (do_wake)
                netif_wake_queue(dev);

        /*
         * First, grab all of the stats for the incoming packet.
         * These get messed up if we get called due to a busy condition.
         */
        bdp = fep->cur_rx;

        while (((sc = CBDR_SC(bdp)) & BD_ENET_RX_EMPTY) == 0 &&
               received < budget) {
                curidx = bdp - fep->rx_bd_base;

                /*
                 * Since we have allocated space to hold a complete frame,
                 * the last indicator should be set.
                 */
                if ((sc & BD_ENET_RX_LAST) == 0)
                        dev_warn(fep->dev, "rcv is not +last\n");

                /*
                 * Check for errors.
                 */
                if (sc & (BD_ENET_RX_LG | BD_ENET_RX_SH | BD_ENET_RX_CL |
                          BD_ENET_RX_NO | BD_ENET_RX_CR | BD_ENET_RX_OV)) {
                        dev->stats.rx_errors++;
                        /* Frame too long or too short. */
                        if (sc & (BD_ENET_RX_LG | BD_ENET_RX_SH))
                                dev->stats.rx_length_errors++;
                        /* Frame alignment */
                        if (sc & (BD_ENET_RX_NO | BD_ENET_RX_CL))
                                dev->stats.rx_frame_errors++;
                        /* CRC Error */
                        if (sc & BD_ENET_RX_CR)
                                dev->stats.rx_crc_errors++;
                        /* FIFO overrun */
                        if (sc & BD_ENET_RX_OV)
                                dev->stats.rx_crc_errors++;

                        skbn = fep->rx_skbuff[curidx];
                } else {
                        skb = fep->rx_skbuff[curidx];

                        /*
                         * Process the incoming frame.
                         */
                        dev->stats.rx_packets++;
                        pkt_len = CBDR_DATLEN(bdp) - 4; /* remove CRC */
                        dev->stats.rx_bytes += pkt_len + 4;

                        if (pkt_len <= fpi->rx_copybreak) {
                                /* +2 to make IP header L1 cache aligned */
                                skbn = netdev_alloc_skb(dev, pkt_len + 2);
                                if (skbn != NULL) {
                                        skb_reserve(skbn, 2);   /* align IP header */
                                        skb_copy_from_linear_data(skb,
                                                      skbn->data, pkt_len);
                                        swap(skb, skbn);
                                        dma_sync_single_for_cpu(fep->dev,
                                                CBDR_BUFADDR(bdp),
                                                L1_CACHE_ALIGN(pkt_len),
                                                DMA_FROM_DEVICE);
                                }
                        } else {
                                skbn = netdev_alloc_skb(dev, ENET_RX_FRSIZE);

                                if (skbn) {
                                        dma_addr_t dma;

                                        skb_align(skbn, ENET_RX_ALIGN);

                                        dma_unmap_single(fep->dev,
                                                CBDR_BUFADDR(bdp),
                                                L1_CACHE_ALIGN(PKT_MAXBUF_SIZE),
                                                DMA_FROM_DEVICE);

                                        dma = dma_map_single(fep->dev,
                                                skbn->data,
                                                L1_CACHE_ALIGN(PKT_MAXBUF_SIZE),
                                                DMA_FROM_DEVICE);
                                        CBDW_BUFADDR(bdp, dma);
                                }
                        }

                        if (skbn != NULL) {
                                skb_put(skb, pkt_len);  /* Make room */
                                skb->protocol = eth_type_trans(skb, dev);
                                received++;
                                netif_receive_skb(skb);
                        } else {
                                dev->stats.rx_dropped++;
                                skbn = skb;
                        }
                }

                fep->rx_skbuff[curidx] = skbn;
                CBDW_DATLEN(bdp, 0);
                CBDW_SC(bdp, (sc & ~BD_ENET_RX_STATS) | BD_ENET_RX_EMPTY);

                /*
                 * Update BD pointer to next entry.
                 */
                if ((sc & BD_ENET_RX_WRAP) == 0)
                        bdp++;
                else
                        bdp = fep->rx_bd_base;

                (*fep->ops->rx_bd_done)(dev);
        }

        fep->cur_rx = bdp;

        if (received < budget && tx_left) {
                /* done */
                napi_complete_done(napi, received);
                (*fep->ops->napi_enable)(dev);

                return received;
        }

        return budget;
}

/*
 * The interrupt handler.
 * This is called from the MPC core interrupt.
 */
static irqreturn_t
fs_enet_interrupt(int irq, void *dev_id)
{
        struct net_device *dev = dev_id;
        struct fs_enet_private *fep;
        const struct fs_platform_info *fpi;
        u32 int_events;
        u32 int_clr_events;
        int nr, napi_ok;
        int handled;

        fep = netdev_priv(dev);
        fpi = fep->fpi;

        nr = 0;
        while ((int_events = (*fep->ops->get_int_events)(dev)) != 0) {
                nr++;

                int_clr_events = int_events;
                int_clr_events &= ~fep->ev_napi;

                (*fep->ops->clear_int_events)(dev, int_clr_events);

                if (int_events & fep->ev_err)
                        (*fep->ops->ev_error)(dev, int_events);

                if (int_events & fep->ev) {
                        napi_ok = napi_schedule_prep(&fep->napi);

                        (*fep->ops->napi_disable)(dev);
                        (*fep->ops->clear_int_events)(dev, fep->ev_napi);

                        /* NOTE: it is possible for FCCs in NAPI mode    */
                        /* to submit a spurious interrupt while in poll  */
                        if (napi_ok)
                                __napi_schedule(&fep->napi);
                }

        }

        handled = nr > 0;
        return IRQ_RETVAL(handled);
}

void fs_init_bds(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        cbd_t __iomem *bdp;
        struct sk_buff *skb;
        int i;

        fs_cleanup_bds(dev);

        fep->dirty_tx = fep->cur_tx = fep->tx_bd_base;
        fep->tx_free = fep->tx_ring;
        fep->cur_rx = fep->rx_bd_base;

        /*
         * Initialize the receive buffer descriptors.
         */
        for (i = 0, bdp = fep->rx_bd_base; i < fep->rx_ring; i++, bdp++) {
                skb = netdev_alloc_skb(dev, ENET_RX_FRSIZE);
                if (skb == NULL)
                        break;

                skb_align(skb, ENET_RX_ALIGN);
                fep->rx_skbuff[i] = skb;
                CBDW_BUFADDR(bdp,
                        dma_map_single(fep->dev, skb->data,
                                L1_CACHE_ALIGN(PKT_MAXBUF_SIZE),
                                DMA_FROM_DEVICE));
                CBDW_DATLEN(bdp, 0);    /* zero */
                CBDW_SC(bdp, BD_ENET_RX_EMPTY |
                        ((i < fep->rx_ring - 1) ? 0 : BD_SC_WRAP));
        }
        /*
         * if we failed, fillup remainder
         */
        for (; i < fep->rx_ring; i++, bdp++) {
                fep->rx_skbuff[i] = NULL;
                CBDW_SC(bdp, (i < fep->rx_ring - 1) ? 0 : BD_SC_WRAP);
        }

        /*
         * ...and the same for transmit.
         */
        for (i = 0, bdp = fep->tx_bd_base; i < fep->tx_ring; i++, bdp++) {
                fep->tx_skbuff[i] = NULL;
                CBDW_BUFADDR(bdp, 0);
                CBDW_DATLEN(bdp, 0);
                CBDW_SC(bdp, (i < fep->tx_ring - 1) ? 0 : BD_SC_WRAP);
        }
}

void fs_cleanup_bds(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        struct sk_buff *skb;
        cbd_t __iomem *bdp;
        int i;

        /*
         * Reset SKB transmit buffers.
         */
        for (i = 0, bdp = fep->tx_bd_base; i < fep->tx_ring; i++, bdp++) {
                if ((skb = fep->tx_skbuff[i]) == NULL)
                        continue;

                /* unmap */
                dma_unmap_single(fep->dev, CBDR_BUFADDR(bdp),
                                skb->len, DMA_TO_DEVICE);

                fep->tx_skbuff[i] = NULL;
                dev_kfree_skb(skb);
        }

        /*
         * Reset SKB receive buffers
         */
        for (i = 0, bdp = fep->rx_bd_base; i < fep->rx_ring; i++, bdp++) {
                if ((skb = fep->rx_skbuff[i]) == NULL)
                        continue;

                /* unmap */
                dma_unmap_single(fep->dev, CBDR_BUFADDR(bdp),
                        L1_CACHE_ALIGN(PKT_MAXBUF_SIZE),
                        DMA_FROM_DEVICE);

                fep->rx_skbuff[i] = NULL;

                dev_kfree_skb(skb);
        }
}

/**********************************************************************************/

#ifdef CONFIG_FS_ENET_MPC5121_FEC
/*
 * MPC5121 FEC requeries 4-byte alignment for TX data buffer!
 */
static struct sk_buff *tx_skb_align_workaround(struct net_device *dev,
                                               struct sk_buff *skb)
{
        struct sk_buff *new_skb;

        if (skb_linearize(skb))
                return NULL;

        /* Alloc new skb */
        new_skb = netdev_alloc_skb(dev, skb->len + 4);
        if (!new_skb)
                return NULL;

        /* Make sure new skb is properly aligned */
        skb_align(new_skb, 4);

        /* Copy data to new skb ... */
        skb_copy_from_linear_data(skb, new_skb->data, skb->len);
        skb_put(new_skb, skb->len);

        /* ... and free an old one */
        dev_kfree_skb_any(skb);

        return new_skb;
}
#endif

static netdev_tx_t
fs_enet_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        cbd_t __iomem *bdp;
        int curidx;
        u16 sc;
        int nr_frags;
        skb_frag_t *frag;
        int len;
#ifdef CONFIG_FS_ENET_MPC5121_FEC
        int is_aligned = 1;
        int i;

        if (!IS_ALIGNED((unsigned long)skb->data, 4)) {
                is_aligned = 0;
        } else {
                nr_frags = skb_shinfo(skb)->nr_frags;
                frag = skb_shinfo(skb)->frags;
                for (i = 0; i < nr_frags; i++, frag++) {
                        if (!IS_ALIGNED(skb_frag_off(frag), 4)) {
                                is_aligned = 0;
                                break;
                        }
                }
        }

        if (!is_aligned) {
                skb = tx_skb_align_workaround(dev, skb);
                if (!skb) {
                        /*
                         * We have lost packet due to memory allocation error
                         * in tx_skb_align_workaround(). Hopefully original
                         * skb is still valid, so try transmit it later.
                         */
                        return NETDEV_TX_BUSY;
                }
        }
#endif

        spin_lock(&fep->tx_lock);

        /*
         * Fill in a Tx ring entry
         */
        bdp = fep->cur_tx;

        nr_frags = skb_shinfo(skb)->nr_frags;
        if (fep->tx_free <= nr_frags || (CBDR_SC(bdp) & BD_ENET_TX_READY)) {
                netif_stop_queue(dev);
                spin_unlock(&fep->tx_lock);

                /*
                 * Ooops.  All transmit buffers are full.  Bail out.
                 * This should not happen, since the tx queue should be stopped.
                 */
                dev_warn(fep->dev, "tx queue full!.\n");
                return NETDEV_TX_BUSY;
        }

        curidx = bdp - fep->tx_bd_base;

        len = skb->len;
        dev->stats.tx_bytes += len;
        if (nr_frags)
                len -= skb->data_len;
        fep->tx_free -= nr_frags + 1;
        /*
         * Push the data cache so the CPM does not get stale memory data.
         */
        CBDW_BUFADDR(bdp, dma_map_single(fep->dev,
                                skb->data, len, DMA_TO_DEVICE));
        CBDW_DATLEN(bdp, len);

        fep->mapped_as_page[curidx] = 0;
        frag = skb_shinfo(skb)->frags;
        while (nr_frags) {
                CBDC_SC(bdp,
                        BD_ENET_TX_STATS | BD_ENET_TX_INTR | BD_ENET_TX_LAST |
                        BD_ENET_TX_TC);
                CBDS_SC(bdp, BD_ENET_TX_READY);

                if ((CBDR_SC(bdp) & BD_ENET_TX_WRAP) == 0) {
                        bdp++;
                        curidx++;
                } else {
                        bdp = fep->tx_bd_base;
                        curidx = 0;
                }

                len = skb_frag_size(frag);
                CBDW_BUFADDR(bdp, skb_frag_dma_map(fep->dev, frag, 0, len,
                                                   DMA_TO_DEVICE));
                CBDW_DATLEN(bdp, len);

                fep->tx_skbuff[curidx] = NULL;
                fep->mapped_as_page[curidx] = 1;

                frag++;
                nr_frags--;
        }

        /* Trigger transmission start */
        sc = BD_ENET_TX_READY | BD_ENET_TX_INTR |
             BD_ENET_TX_LAST | BD_ENET_TX_TC;

        /* note that while FEC does not have this bit
         * it marks it as available for software use
         * yay for hw reuse :) */
        if (skb->len <= 60)
                sc |= BD_ENET_TX_PAD;
        CBDC_SC(bdp, BD_ENET_TX_STATS);
        CBDS_SC(bdp, sc);

        /* Save skb pointer. */
        fep->tx_skbuff[curidx] = skb;

        /* If this was the last BD in the ring, start at the beginning again. */
        if ((CBDR_SC(bdp) & BD_ENET_TX_WRAP) == 0)
                bdp++;
        else
                bdp = fep->tx_bd_base;
        fep->cur_tx = bdp;

        if (fep->tx_free < MAX_SKB_FRAGS)
                netif_stop_queue(dev);

        skb_tx_timestamp(skb);

        (*fep->ops->tx_kickstart)(dev);

        spin_unlock(&fep->tx_lock);

        return NETDEV_TX_OK;
}

static void fs_timeout_work(struct work_struct *work)
{
        struct fs_enet_private *fep = container_of(work, struct fs_enet_private,
                                                   timeout_work);
        struct net_device *dev = fep->ndev;
        unsigned long flags;
        int wake = 0;

        dev->stats.tx_errors++;

        spin_lock_irqsave(&fep->lock, flags);

        if (dev->flags & IFF_UP) {
                phy_stop(dev->phydev);
                (*fep->ops->stop)(dev);
                (*fep->ops->restart)(dev);
        }

        phy_start(dev->phydev);
        wake = fep->tx_free >= MAX_SKB_FRAGS &&
               !(CBDR_SC(fep->cur_tx) & BD_ENET_TX_READY);
        spin_unlock_irqrestore(&fep->lock, flags);

        if (wake)
                netif_wake_queue(dev);
}

static void fs_timeout(struct net_device *dev, unsigned int txqueue)
{
        struct fs_enet_private *fep = netdev_priv(dev);

        schedule_work(&fep->timeout_work);
}

/*-----------------------------------------------------------------------------
 *  generic link-change handler - should be sufficient for most cases
 *-----------------------------------------------------------------------------*/
static void generic_adjust_link(struct  net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        struct phy_device *phydev = dev->phydev;
        int new_state = 0;

        if (phydev->link) {
                /* adjust to duplex mode */
                if (phydev->duplex != fep->oldduplex) {
                        new_state = 1;
                        fep->oldduplex = phydev->duplex;
                }

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

                if (!fep->oldlink) {
                        new_state = 1;
                        fep->oldlink = 1;
                }

                if (new_state)
                        fep->ops->restart(dev);
        } else if (fep->oldlink) {
                new_state = 1;
                fep->oldlink = 0;
                fep->oldspeed = 0;
                fep->oldduplex = -1;
        }

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


static void fs_adjust_link(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        unsigned long flags;

        spin_lock_irqsave(&fep->lock, flags);

        if(fep->ops->adjust_link)
                fep->ops->adjust_link(dev);
        else
                generic_adjust_link(dev);

        spin_unlock_irqrestore(&fep->lock, flags);
}

static int fs_init_phy(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        struct phy_device *phydev;
        phy_interface_t iface;

        fep->oldlink = 0;
        fep->oldspeed = 0;
        fep->oldduplex = -1;

        iface = fep->fpi->use_rmii ?
                PHY_INTERFACE_MODE_RMII : PHY_INTERFACE_MODE_MII;

        phydev = of_phy_connect(dev, fep->fpi->phy_node, &fs_adjust_link, 0,
                                iface);
        if (!phydev) {
                dev_err(&dev->dev, "Could not attach to PHY\n");
                return -ENODEV;
        }

        return 0;
}

static int fs_enet_open(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        int r;
        int err;

        /* to initialize the fep->cur_rx,... */
        /* not doing this, will cause a crash in fs_enet_napi */
        fs_init_bds(fep->ndev);

        napi_enable(&fep->napi);

        /* Install our interrupt handler. */
        r = request_irq(fep->interrupt, fs_enet_interrupt, IRQF_SHARED,
                        "fs_enet-mac", dev);
        if (r != 0) {
                dev_err(fep->dev, "Could not allocate FS_ENET IRQ!");
                napi_disable(&fep->napi);
                return -EINVAL;
        }

        err = fs_init_phy(dev);
        if (err) {
                free_irq(fep->interrupt, dev);
                napi_disable(&fep->napi);
                return err;
        }
        phy_start(dev->phydev);

        netif_start_queue(dev);

        return 0;
}

static int fs_enet_close(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        unsigned long flags;

        netif_stop_queue(dev);
        netif_carrier_off(dev);
        napi_disable(&fep->napi);
        cancel_work_sync(&fep->timeout_work);
        phy_stop(dev->phydev);

        spin_lock_irqsave(&fep->lock, flags);
        spin_lock(&fep->tx_lock);
        (*fep->ops->stop)(dev);
        spin_unlock(&fep->tx_lock);
        spin_unlock_irqrestore(&fep->lock, flags);

        /* release any irqs */
        phy_disconnect(dev->phydev);
        free_irq(fep->interrupt, dev);

        return 0;
}

/*************************************************************************/

static void fs_get_drvinfo(struct net_device *dev,
                            struct ethtool_drvinfo *info)
{
        strlcpy(info->driver, DRV_MODULE_NAME, sizeof(info->driver));
}

static int fs_get_regs_len(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);

        return (*fep->ops->get_regs_len)(dev);
}

static void fs_get_regs(struct net_device *dev, struct ethtool_regs *regs,
                         void *p)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        unsigned long flags;
        int r, len;

        len = regs->len;

        spin_lock_irqsave(&fep->lock, flags);
        r = (*fep->ops->get_regs)(dev, p, &len);
        spin_unlock_irqrestore(&fep->lock, flags);

        if (r == 0)
                regs->version = 0;
}

static u32 fs_get_msglevel(struct net_device *dev)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        return fep->msg_enable;
}

static void fs_set_msglevel(struct net_device *dev, u32 value)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        fep->msg_enable = value;
}

static int fs_get_tunable(struct net_device *dev,
                          const struct ethtool_tunable *tuna, void *data)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        struct fs_platform_info *fpi = fep->fpi;
        int ret = 0;

        switch (tuna->id) {
        case ETHTOOL_RX_COPYBREAK:
                *(u32 *)data = fpi->rx_copybreak;
                break;
        default:
                ret = -EINVAL;
                break;
        }

        return ret;
}

static int fs_set_tunable(struct net_device *dev,
                          const struct ethtool_tunable *tuna, const void *data)
{
        struct fs_enet_private *fep = netdev_priv(dev);
        struct fs_platform_info *fpi = fep->fpi;
        int ret = 0;

        switch (tuna->id) {
        case ETHTOOL_RX_COPYBREAK:
                fpi->rx_copybreak = *(u32 *)data;
                break;
        default:
                ret = -EINVAL;
                break;
        }

        return ret;
}

static const struct ethtool_ops fs_ethtool_ops = {
        .get_drvinfo = fs_get_drvinfo,
        .get_regs_len = fs_get_regs_len,
        .nway_reset = phy_ethtool_nway_reset,
        .get_link = ethtool_op_get_link,
        .get_msglevel = fs_get_msglevel,
        .set_msglevel = fs_set_msglevel,
        .get_regs = fs_get_regs,
        .get_ts_info = ethtool_op_get_ts_info,
        .get_link_ksettings = phy_ethtool_get_link_ksettings,
        .set_link_ksettings = phy_ethtool_set_link_ksettings,
        .get_tunable = fs_get_tunable,
        .set_tunable = fs_set_tunable,
};

extern int fs_mii_connect(struct net_device *dev);
extern void fs_mii_disconnect(struct net_device *dev);

/**************************************************************************************/

#ifdef CONFIG_FS_ENET_HAS_FEC
#define IS_FEC(match) ((match)->data == &fs_fec_ops)
#else
#define IS_FEC(match) 0
#endif

static const struct net_device_ops fs_enet_netdev_ops = {
        .ndo_open               = fs_enet_open,
        .ndo_stop               = fs_enet_close,
        .ndo_start_xmit         = fs_enet_start_xmit,
        .ndo_tx_timeout         = fs_timeout,
        .ndo_set_rx_mode        = fs_set_multicast_list,
        .ndo_do_ioctl           = phy_do_ioctl_running,
        .ndo_validate_addr      = eth_validate_addr,
        .ndo_set_mac_address    = eth_mac_addr,
#ifdef CONFIG_NET_POLL_CONTROLLER
        .ndo_poll_controller    = fs_enet_netpoll,
#endif
};

static const struct of_device_id fs_enet_match[];
static int fs_enet_probe(struct platform_device *ofdev)
{
        const struct of_device_id *match;
        struct net_device *ndev;
        struct fs_enet_private *fep;
        struct fs_platform_info *fpi;
        const u32 *data;
        struct clk *clk;
        int err;
        const u8 *mac_addr;
        const char *phy_connection_type;
        int privsize, len, ret = -ENODEV;

        match = of_match_device(fs_enet_match, &ofdev->dev);
        if (!match)
                return -EINVAL;

        fpi = kzalloc(sizeof(*fpi), GFP_KERNEL);
        if (!fpi)
                return -ENOMEM;

        if (!IS_FEC(match)) {
                data = of_get_property(ofdev->dev.of_node, "fsl,cpm-command", &len);
                if (!data || len != 4)
                        goto out_free_fpi;

                fpi->cp_command = *data;
        }

        fpi->rx_ring = RX_RING_SIZE;
        fpi->tx_ring = TX_RING_SIZE;
        fpi->rx_copybreak = 240;
        fpi->napi_weight = 17;
        fpi->phy_node = of_parse_phandle(ofdev->dev.of_node, "phy-handle", 0);
        if (!fpi->phy_node && of_phy_is_fixed_link(ofdev->dev.of_node)) {
                err = of_phy_register_fixed_link(ofdev->dev.of_node);
                if (err)
                        goto out_free_fpi;

                /* In the case of a fixed PHY, the DT node associated
                 * to the PHY is the Ethernet MAC DT node.
                 */
                fpi->phy_node = of_node_get(ofdev->dev.of_node);
        }

        if (of_device_is_compatible(ofdev->dev.of_node, "fsl,mpc5125-fec")) {
                phy_connection_type = of_get_property(ofdev->dev.of_node,
                                                "phy-connection-type", NULL);
                if (phy_connection_type && !strcmp("rmii", phy_connection_type))
                        fpi->use_rmii = 1;
        }

        /* make clock lookup non-fatal (the driver is shared among platforms),
         * but require enable to succeed when a clock was specified/found,
         * keep a reference to the clock upon successful acquisition
         */
        clk = devm_clk_get(&ofdev->dev, "per");
        if (!IS_ERR(clk)) {
                ret = clk_prepare_enable(clk);
                if (ret)
                        goto out_deregister_fixed_link;

                fpi->clk_per = clk;
        }

        privsize = sizeof(*fep) +
                   sizeof(struct sk_buff **) *
                     (fpi->rx_ring + fpi->tx_ring) +
                   sizeof(char) * fpi->tx_ring;

        ndev = alloc_etherdev(privsize);
        if (!ndev) {
                ret = -ENOMEM;
                goto out_put;
        }

        SET_NETDEV_DEV(ndev, &ofdev->dev);
        platform_set_drvdata(ofdev, ndev);

        fep = netdev_priv(ndev);
        fep->dev = &ofdev->dev;
        fep->ndev = ndev;
        fep->fpi = fpi;
        fep->ops = match->data;

        ret = fep->ops->setup_data(ndev);
        if (ret)
                goto out_free_dev;

        fep->rx_skbuff = (struct sk_buff **)&fep[1];
        fep->tx_skbuff = fep->rx_skbuff + fpi->rx_ring;
        fep->mapped_as_page = (char *)(fep->rx_skbuff + fpi->rx_ring +
                                       fpi->tx_ring);

        spin_lock_init(&fep->lock);
        spin_lock_init(&fep->tx_lock);

        mac_addr = of_get_mac_address(ofdev->dev.of_node);
        if (!IS_ERR(mac_addr))
                ether_addr_copy(ndev->dev_addr, mac_addr);

        ret = fep->ops->allocate_bd(ndev);
        if (ret)
                goto out_cleanup_data;

        fep->rx_bd_base = fep->ring_base;
        fep->tx_bd_base = fep->rx_bd_base + fpi->rx_ring;

        fep->tx_ring = fpi->tx_ring;
        fep->rx_ring = fpi->rx_ring;

        ndev->netdev_ops = &fs_enet_netdev_ops;
        ndev->watchdog_timeo = 2 * HZ;
        INIT_WORK(&fep->timeout_work, fs_timeout_work);
        netif_napi_add(ndev, &fep->napi, fs_enet_napi, fpi->napi_weight);

        ndev->ethtool_ops = &fs_ethtool_ops;

        netif_carrier_off(ndev);

        ndev->features |= NETIF_F_SG;

        ret = register_netdev(ndev);
        if (ret)
                goto out_free_bd;

        pr_info("%s: fs_enet: %pM\n", ndev->name, ndev->dev_addr);

        return 0;

out_free_bd:
        fep->ops->free_bd(ndev);
out_cleanup_data:
        fep->ops->cleanup_data(ndev);
out_free_dev:
        free_netdev(ndev);
out_put:
        clk_disable_unprepare(fpi->clk_per);
out_deregister_fixed_link:
        of_node_put(fpi->phy_node);
        if (of_phy_is_fixed_link(ofdev->dev.of_node))
                of_phy_deregister_fixed_link(ofdev->dev.of_node);
out_free_fpi:
        kfree(fpi);
        return ret;
}

static int fs_enet_remove(struct platform_device *ofdev)
{
        struct net_device *ndev = platform_get_drvdata(ofdev);
        struct fs_enet_private *fep = netdev_priv(ndev);

        unregister_netdev(ndev);

        fep->ops->free_bd(ndev);
        fep->ops->cleanup_data(ndev);
        dev_set_drvdata(fep->dev, NULL);
        of_node_put(fep->fpi->phy_node);
        clk_disable_unprepare(fep->fpi->clk_per);
        if (of_phy_is_fixed_link(ofdev->dev.of_node))
                of_phy_deregister_fixed_link(ofdev->dev.of_node);
        free_netdev(ndev);
        return 0;
}

static const struct of_device_id fs_enet_match[] = {
#ifdef CONFIG_FS_ENET_HAS_SCC
        {
                .compatible = "fsl,cpm1-scc-enet",
                .data = (void *)&fs_scc_ops,
        },
        {
                .compatible = "fsl,cpm2-scc-enet",
                .data = (void *)&fs_scc_ops,
        },
#endif
#ifdef CONFIG_FS_ENET_HAS_FCC
        {
                .compatible = "fsl,cpm2-fcc-enet",
                .data = (void *)&fs_fcc_ops,
        },
#endif
#ifdef CONFIG_FS_ENET_HAS_FEC
#ifdef CONFIG_FS_ENET_MPC5121_FEC
        {
                .compatible = "fsl,mpc5121-fec",
                .data = (void *)&fs_fec_ops,
        },
        {
                .compatible = "fsl,mpc5125-fec",
                .data = (void *)&fs_fec_ops,
        },
#else
        {
                .compatible = "fsl,pq1-fec-enet",
                .data = (void *)&fs_fec_ops,
        },
#endif
#endif
        {}
};
MODULE_DEVICE_TABLE(of, fs_enet_match);

static struct platform_driver fs_enet_driver = {
        .driver = {
                .name = "fs_enet",
                .of_match_table = fs_enet_match,
        },
        .probe = fs_enet_probe,
        .remove = fs_enet_remove,
};

#ifdef CONFIG_NET_POLL_CONTROLLER
static void fs_enet_netpoll(struct net_device *dev)
{
       disable_irq(dev->irq);
       fs_enet_interrupt(dev->irq, dev);
       enable_irq(dev->irq);
}
#endif

module_platform_driver(fs_enet_driver);