net/fec: clean suspend/resume

[linux-2.6/libata-dev.git] / drivers / net / fec.c

/*
 * Fast Ethernet Controller (FEC) driver for Motorola MPC8xx.
 * Copyright (c) 1997 Dan Malek (dmalek@jlc.net)
 *
 * Right now, I am very wasteful with the buffers.  I allocate memory
 * pages and then divide them into 2K frame buffers.  This way I know I
 * have buffers large enough to hold one frame within one buffer descriptor.
 * Once I get this working, I will use 64 or 128 byte CPM buffers, which
 * will be much more memory efficient and will easily handle lots of
 * small packets.
 *
 * Much better multiple PHY support by Magnus Damm.
 * Copyright (c) 2000 Ericsson Radio Systems AB.
 *
 * Support for FEC controller of ColdFire processors.
 * Copyright (c) 2001-2005 Greg Ungerer (gerg@snapgear.com)
 *
 * Bug fixes and cleanup by Philippe De Muyter (phdm@macqel.be)
 * Copyright (c) 2004-2006 Macq Electronique SA.
 */

#include <linux/module.h>
#include <linux/kernel.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/pci.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include <linux/bitops.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/clk.h>
#include <linux/platform_device.h>
#include <linux/phy.h>
#include <linux/fec.h>

#include <asm/cacheflush.h>

#ifndef CONFIG_ARCH_MXC
#include <asm/coldfire.h>
#include <asm/mcfsim.h>
#endif

#include "fec.h"

#ifdef CONFIG_ARCH_MXC
#include <mach/hardware.h>
#define FEC_ALIGNMENT   0xf
#else
#define FEC_ALIGNMENT   0x3
#endif

/*
 * Define the fixed address of the FEC hardware.
 */
#if defined(CONFIG_M5272)

static unsigned char    fec_mac_default[] = {
        0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
};

/*
 * Some hardware gets it MAC address out of local flash memory.
 * if this is non-zero then assume it is the address to get MAC from.
 */
#if defined(CONFIG_NETtel)
#define FEC_FLASHMAC    0xf0006006
#elif defined(CONFIG_GILBARCONAP) || defined(CONFIG_SCALES)
#define FEC_FLASHMAC    0xf0006000
#elif defined(CONFIG_CANCam)
#define FEC_FLASHMAC    0xf0020000
#elif defined (CONFIG_M5272C3)
#define FEC_FLASHMAC    (0xffe04000 + 4)
#elif defined(CONFIG_MOD5272)
#define FEC_FLASHMAC    0xffc0406b
#else
#define FEC_FLASHMAC    0
#endif
#endif /* CONFIG_M5272 */

/* The number of Tx and Rx buffers.  These are allocated from the page
 * pool.  The code may assume these are power of two, so it it best
 * to keep them that size.
 * We don't need to allocate pages for the transmitter.  We just use
 * the skbuffer directly.
 */
#define FEC_ENET_RX_PAGES       8
#define FEC_ENET_RX_FRSIZE      2048
#define FEC_ENET_RX_FRPPG       (PAGE_SIZE / FEC_ENET_RX_FRSIZE)
#define RX_RING_SIZE            (FEC_ENET_RX_FRPPG * FEC_ENET_RX_PAGES)
#define FEC_ENET_TX_FRSIZE      2048
#define FEC_ENET_TX_FRPPG       (PAGE_SIZE / FEC_ENET_TX_FRSIZE)
#define TX_RING_SIZE            16      /* Must be power of two */
#define TX_RING_MOD_MASK        15      /*   for this to work */

#if (((RX_RING_SIZE + TX_RING_SIZE) * 8) > PAGE_SIZE)
#error "FEC: descriptor ring size constants too large"
#endif

/* Interrupt events/masks. */
#define FEC_ENET_HBERR  ((uint)0x80000000)      /* Heartbeat error */
#define FEC_ENET_BABR   ((uint)0x40000000)      /* Babbling receiver */
#define FEC_ENET_BABT   ((uint)0x20000000)      /* Babbling transmitter */
#define FEC_ENET_GRA    ((uint)0x10000000)      /* Graceful stop complete */
#define FEC_ENET_TXF    ((uint)0x08000000)      /* Full frame transmitted */
#define FEC_ENET_TXB    ((uint)0x04000000)      /* A buffer was transmitted */
#define FEC_ENET_RXF    ((uint)0x02000000)      /* Full frame received */
#define FEC_ENET_RXB    ((uint)0x01000000)      /* A buffer was received */
#define FEC_ENET_MII    ((uint)0x00800000)      /* MII interrupt */
#define FEC_ENET_EBERR  ((uint)0x00400000)      /* SDMA bus error */

/* The FEC stores dest/src/type, data, and checksum for receive packets.
 */
#define PKT_MAXBUF_SIZE         1518
#define PKT_MINBUF_SIZE         64
#define PKT_MAXBLR_SIZE         1520


/*
 * The 5270/5271/5280/5282/532x RX control register also contains maximum frame
 * size bits. Other FEC hardware does not, so we need to take that into
 * account when setting it.
 */
#if defined(CONFIG_M523x) || defined(CONFIG_M527x) || defined(CONFIG_M528x) || \
    defined(CONFIG_M520x) || defined(CONFIG_M532x) || defined(CONFIG_ARCH_MXC)
#define OPT_FRAME_SIZE  (PKT_MAXBUF_SIZE << 16)
#else
#define OPT_FRAME_SIZE  0
#endif

/* The FEC buffer descriptors track the ring buffers.  The rx_bd_base and
 * tx_bd_base always point to the base of the buffer descriptors.  The
 * cur_rx and cur_tx point to the currently available buffer.
 * The dirty_tx tracks the current buffer that is being sent by the
 * controller.  The cur_tx and dirty_tx are equal under both completely
 * empty and completely full conditions.  The empty/ready indicator in
 * the buffer descriptor determines the actual condition.
 */
struct fec_enet_private {
        /* Hardware registers of the FEC device */
        void __iomem *hwp;

        struct net_device *netdev;

        struct clk *clk;

        /* The saved address of a sent-in-place packet/buffer, for skfree(). */
        unsigned char *tx_bounce[TX_RING_SIZE];
        struct  sk_buff* tx_skbuff[TX_RING_SIZE];
        struct  sk_buff* rx_skbuff[RX_RING_SIZE];
        ushort  skb_cur;
        ushort  skb_dirty;

        /* CPM dual port RAM relative addresses */
        dma_addr_t      bd_dma;
        /* Address of Rx and Tx buffers */
        struct bufdesc  *rx_bd_base;
        struct bufdesc  *tx_bd_base;
        /* The next free ring entry */
        struct bufdesc  *cur_rx, *cur_tx; 
        /* The ring entries to be free()ed */
        struct bufdesc  *dirty_tx;

        uint    tx_full;
        /* hold while accessing the HW like ringbuffer for tx/rx but not MAC */
        spinlock_t hw_lock;

        struct  platform_device *pdev;

        int     opened;

        /* Phylib and MDIO interface */
        struct  mii_bus *mii_bus;
        struct  phy_device *phy_dev;
        int     mii_timeout;
        uint    phy_speed;
        phy_interface_t phy_interface;
        int     index;
        int     link;
        int     full_duplex;
};

static irqreturn_t fec_enet_interrupt(int irq, void * dev_id);
static void fec_enet_tx(struct net_device *dev);
static void fec_enet_rx(struct net_device *dev);
static int fec_enet_close(struct net_device *dev);
static void fec_restart(struct net_device *dev, int duplex);
static void fec_stop(struct net_device *dev);

/* FEC MII MMFR bits definition */
#define FEC_MMFR_ST             (1 << 30)
#define FEC_MMFR_OP_READ        (2 << 28)
#define FEC_MMFR_OP_WRITE       (1 << 28)
#define FEC_MMFR_PA(v)          ((v & 0x1f) << 23)
#define FEC_MMFR_RA(v)          ((v & 0x1f) << 18)
#define FEC_MMFR_TA             (2 << 16)
#define FEC_MMFR_DATA(v)        (v & 0xffff)

#define FEC_MII_TIMEOUT         10000

/* Transmitter timeout */
#define TX_TIMEOUT (2 * HZ)

static netdev_tx_t
fec_enet_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
        struct fec_enet_private *fep = netdev_priv(dev);
        struct bufdesc *bdp;
        void *bufaddr;
        unsigned short  status;
        unsigned long flags;

        if (!fep->link) {
                /* Link is down or autonegotiation is in progress. */
                return NETDEV_TX_BUSY;
        }

        spin_lock_irqsave(&fep->hw_lock, flags);
        /* Fill in a Tx ring entry */
        bdp = fep->cur_tx;

        status = bdp->cbd_sc;

        if (status & BD_ENET_TX_READY) {
                /* Ooops.  All transmit buffers are full.  Bail out.
                 * This should not happen, since dev->tbusy should be set.
                 */
                printk("%s: tx queue full!.\n", dev->name);
                spin_unlock_irqrestore(&fep->hw_lock, flags);
                return NETDEV_TX_BUSY;
        }

        /* Clear all of the status flags */
        status &= ~BD_ENET_TX_STATS;

        /* Set buffer length and buffer pointer */
        bufaddr = skb->data;
        bdp->cbd_datlen = skb->len;

        /*
         * On some FEC implementations data must be aligned on
         * 4-byte boundaries. Use bounce buffers to copy data
         * and get it aligned. Ugh.
         */
        if (((unsigned long) bufaddr) & FEC_ALIGNMENT) {
                unsigned int index;
                index = bdp - fep->tx_bd_base;
                memcpy(fep->tx_bounce[index], (void *)skb->data, skb->len);
                bufaddr = fep->tx_bounce[index];
        }

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

        dev->stats.tx_bytes += skb->len;
        fep->skb_cur = (fep->skb_cur+1) & TX_RING_MOD_MASK;

        /* Push the data cache so the CPM does not get stale memory
         * data.
         */
        bdp->cbd_bufaddr = dma_map_single(&dev->dev, bufaddr,
                        FEC_ENET_TX_FRSIZE, DMA_TO_DEVICE);

        /* Send it on its way.  Tell FEC it's ready, interrupt when done,
         * it's the last BD of the frame, and to put the CRC on the end.
         */
        status |= (BD_ENET_TX_READY | BD_ENET_TX_INTR
                        | BD_ENET_TX_LAST | BD_ENET_TX_TC);
        bdp->cbd_sc = status;

        /* Trigger transmission start */
        writel(0, fep->hwp + FEC_X_DES_ACTIVE);

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

        if (bdp == fep->dirty_tx) {
                fep->tx_full = 1;
                netif_stop_queue(dev);
        }

        fep->cur_tx = bdp;

        spin_unlock_irqrestore(&fep->hw_lock, flags);

        return NETDEV_TX_OK;
}

static void
fec_timeout(struct net_device *dev)
{
        struct fec_enet_private *fep = netdev_priv(dev);

        dev->stats.tx_errors++;

        fec_restart(dev, fep->full_duplex);
        netif_wake_queue(dev);
}

static irqreturn_t
fec_enet_interrupt(int irq, void * dev_id)
{
        struct  net_device *dev = dev_id;
        struct fec_enet_private *fep = netdev_priv(dev);
        uint    int_events;
        irqreturn_t ret = IRQ_NONE;

        do {
                int_events = readl(fep->hwp + FEC_IEVENT);
                writel(int_events, fep->hwp + FEC_IEVENT);

                if (int_events & FEC_ENET_RXF) {
                        ret = IRQ_HANDLED;
                        fec_enet_rx(dev);
                }

                /* Transmit OK, or non-fatal error. Update the buffer
                 * descriptors. FEC handles all errors, we just discover
                 * them as part of the transmit process.
                 */
                if (int_events & FEC_ENET_TXF) {
                        ret = IRQ_HANDLED;
                        fec_enet_tx(dev);
                }
        } while (int_events);

        return ret;
}


static void
fec_enet_tx(struct net_device *dev)
{
        struct  fec_enet_private *fep;
        struct bufdesc *bdp;
        unsigned short status;
        struct  sk_buff *skb;

        fep = netdev_priv(dev);
        spin_lock(&fep->hw_lock);
        bdp = fep->dirty_tx;

        while (((status = bdp->cbd_sc) & BD_ENET_TX_READY) == 0) {
                if (bdp == fep->cur_tx && fep->tx_full == 0)
                        break;

                dma_unmap_single(&dev->dev, bdp->cbd_bufaddr, FEC_ENET_TX_FRSIZE, DMA_TO_DEVICE);
                bdp->cbd_bufaddr = 0;

                skb = fep->tx_skbuff[fep->skb_dirty];
                /* Check for errors. */
                if (status & (BD_ENET_TX_HB | BD_ENET_TX_LC |
                                   BD_ENET_TX_RL | BD_ENET_TX_UN |
                                   BD_ENET_TX_CSL)) {
                        dev->stats.tx_errors++;
                        if (status & BD_ENET_TX_HB)  /* No heartbeat */
                                dev->stats.tx_heartbeat_errors++;
                        if (status & BD_ENET_TX_LC)  /* Late collision */
                                dev->stats.tx_window_errors++;
                        if (status & BD_ENET_TX_RL)  /* Retrans limit */
                                dev->stats.tx_aborted_errors++;
                        if (status & BD_ENET_TX_UN)  /* Underrun */
                                dev->stats.tx_fifo_errors++;
                        if (status & BD_ENET_TX_CSL) /* Carrier lost */
                                dev->stats.tx_carrier_errors++;
                } else {
                        dev->stats.tx_packets++;
                }

                if (status & BD_ENET_TX_READY)
                        printk("HEY! Enet xmit interrupt and TX_READY.\n");

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

                /* Free the sk buffer associated with this last transmit */
                dev_kfree_skb_any(skb);
                fep->tx_skbuff[fep->skb_dirty] = NULL;
                fep->skb_dirty = (fep->skb_dirty + 1) & TX_RING_MOD_MASK;

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

                /* Since we have freed up a buffer, the ring is no longer full
                 */
                if (fep->tx_full) {
                        fep->tx_full = 0;
                        if (netif_queue_stopped(dev))
                                netif_wake_queue(dev);
                }
        }
        fep->dirty_tx = bdp;
        spin_unlock(&fep->hw_lock);
}


/* During a receive, the cur_rx points to the current incoming buffer.
 * When we update through the ring, if the next incoming buffer has
 * not been given to the system, we just set the empty indicator,
 * effectively tossing the packet.
 */
static void
fec_enet_rx(struct net_device *dev)
{
        struct  fec_enet_private *fep = netdev_priv(dev);
        struct bufdesc *bdp;
        unsigned short status;
        struct  sk_buff *skb;
        ushort  pkt_len;
        __u8 *data;

#ifdef CONFIG_M532x
        flush_cache_all();
#endif

        spin_lock(&fep->hw_lock);

        /* 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 (!((status = bdp->cbd_sc) & BD_ENET_RX_EMPTY)) {

                /* Since we have allocated space to hold a complete frame,
                 * the last indicator should be set.
                 */
                if ((status & BD_ENET_RX_LAST) == 0)
                        printk("FEC ENET: rcv is not +last\n");

                if (!fep->opened)
                        goto rx_processing_done;

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

                /* Report late collisions as a frame error.
                 * On this error, the BD is closed, but we don't know what we
                 * have in the buffer.  So, just drop this frame on the floor.
                 */
                if (status & BD_ENET_RX_CL) {
                        dev->stats.rx_errors++;
                        dev->stats.rx_frame_errors++;
                        goto rx_processing_done;
                }

                /* Process the incoming frame. */
                dev->stats.rx_packets++;
                pkt_len = bdp->cbd_datlen;
                dev->stats.rx_bytes += pkt_len;
                data = (__u8*)__va(bdp->cbd_bufaddr);

                dma_unmap_single(NULL, bdp->cbd_bufaddr, bdp->cbd_datlen,
                                DMA_FROM_DEVICE);

                /* This does 16 byte alignment, exactly what we need.
                 * The packet length includes FCS, but we don't want to
                 * include that when passing upstream as it messes up
                 * bridging applications.
                 */
                skb = dev_alloc_skb(pkt_len - 4 + NET_IP_ALIGN);

                if (unlikely(!skb)) {
                        printk("%s: Memory squeeze, dropping packet.\n",
                                        dev->name);
                        dev->stats.rx_dropped++;
                } else {
                        skb_reserve(skb, NET_IP_ALIGN);
                        skb_put(skb, pkt_len - 4);      /* Make room */
                        skb_copy_to_linear_data(skb, data, pkt_len - 4);
                        skb->protocol = eth_type_trans(skb, dev);
                        netif_rx(skb);
                }

                bdp->cbd_bufaddr = dma_map_single(NULL, data, bdp->cbd_datlen,
                        DMA_FROM_DEVICE);
rx_processing_done:
                /* Clear the status flags for this buffer */
                status &= ~BD_ENET_RX_STATS;

                /* Mark the buffer empty */
                status |= BD_ENET_RX_EMPTY;
                bdp->cbd_sc = status;

                /* Update BD pointer to next entry */
                if (status & BD_ENET_RX_WRAP)
                        bdp = fep->rx_bd_base;
                else
                        bdp++;
                /* Doing this here will keep the FEC running while we process
                 * incoming frames.  On a heavily loaded network, we should be
                 * able to keep up at the expense of system resources.
                 */
                writel(0, fep->hwp + FEC_R_DES_ACTIVE);
        }
        fep->cur_rx = bdp;

        spin_unlock(&fep->hw_lock);
}

/* ------------------------------------------------------------------------- */
#ifdef CONFIG_M5272
static void __inline__ fec_get_mac(struct net_device *dev)
{
        struct fec_enet_private *fep = netdev_priv(dev);
        unsigned char *iap, tmpaddr[ETH_ALEN];

        if (FEC_FLASHMAC) {
                /*
                 * Get MAC address from FLASH.
                 * If it is all 1's or 0's, use the default.
                 */
                iap = (unsigned char *)FEC_FLASHMAC;
                if ((iap[0] == 0) && (iap[1] == 0) && (iap[2] == 0) &&
                    (iap[3] == 0) && (iap[4] == 0) && (iap[5] == 0))
                        iap = fec_mac_default;
                if ((iap[0] == 0xff) && (iap[1] == 0xff) && (iap[2] == 0xff) &&
                    (iap[3] == 0xff) && (iap[4] == 0xff) && (iap[5] == 0xff))
                        iap = fec_mac_default;
        } else {
                *((unsigned long *) &tmpaddr[0]) = readl(fep->hwp + FEC_ADDR_LOW);
                *((unsigned short *) &tmpaddr[4]) = (readl(fep->hwp + FEC_ADDR_HIGH) >> 16);
                iap = &tmpaddr[0];
        }

        memcpy(dev->dev_addr, iap, ETH_ALEN);

        /* Adjust MAC if using default MAC address */
        if (iap == fec_mac_default)
                 dev->dev_addr[ETH_ALEN-1] = fec_mac_default[ETH_ALEN-1] + fep->index;
}
#endif

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

/*
 * Phy section
 */
static void fec_enet_adjust_link(struct net_device *dev)
{
        struct fec_enet_private *fep = netdev_priv(dev);
        struct phy_device *phy_dev = fep->phy_dev;
        unsigned long flags;

        int status_change = 0;

        spin_lock_irqsave(&fep->hw_lock, flags);

        /* Prevent a state halted on mii error */
        if (fep->mii_timeout && phy_dev->state == PHY_HALTED) {
                phy_dev->state = PHY_RESUMING;
                goto spin_unlock;
        }

        /* Duplex link change */
        if (phy_dev->link) {
                if (fep->full_duplex != phy_dev->duplex) {
                        fec_restart(dev, phy_dev->duplex);
                        status_change = 1;
                }
        }

        /* Link on or off change */
        if (phy_dev->link != fep->link) {
                fep->link = phy_dev->link;
                if (phy_dev->link)
                        fec_restart(dev, phy_dev->duplex);
                else
                        fec_stop(dev);
                status_change = 1;
        }

spin_unlock:
        spin_unlock_irqrestore(&fep->hw_lock, flags);

        if (status_change)
                phy_print_status(phy_dev);
}

/*
 * NOTE: a MII transaction is during around 25 us, so polling it...
 */
static int fec_enet_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
{
        struct fec_enet_private *fep = bus->priv;
        int timeout = FEC_MII_TIMEOUT;

        fep->mii_timeout = 0;

        /* clear MII end of transfer bit*/
        writel(FEC_ENET_MII, fep->hwp + FEC_IEVENT);

        /* start a read op */
        writel(FEC_MMFR_ST | FEC_MMFR_OP_READ |
                FEC_MMFR_PA(mii_id) | FEC_MMFR_RA(regnum) |
                FEC_MMFR_TA, fep->hwp + FEC_MII_DATA);

        /* wait for end of transfer */
        while (!(readl(fep->hwp + FEC_IEVENT) & FEC_ENET_MII)) {
                cpu_relax();
                if (timeout-- < 0) {
                        fep->mii_timeout = 1;
                        printk(KERN_ERR "FEC: MDIO read timeout\n");
                        return -ETIMEDOUT;
                }
        }

        /* return value */
        return FEC_MMFR_DATA(readl(fep->hwp + FEC_MII_DATA));
}

static int fec_enet_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
                           u16 value)
{
        struct fec_enet_private *fep = bus->priv;
        int timeout = FEC_MII_TIMEOUT;

        fep->mii_timeout = 0;

        /* clear MII end of transfer bit*/
        writel(FEC_ENET_MII, fep->hwp + FEC_IEVENT);

        /* start a read op */
        writel(FEC_MMFR_ST | FEC_MMFR_OP_READ |
                FEC_MMFR_PA(mii_id) | FEC_MMFR_RA(regnum) |
                FEC_MMFR_TA | FEC_MMFR_DATA(value),
                fep->hwp + FEC_MII_DATA);

        /* wait for end of transfer */
        while (!(readl(fep->hwp + FEC_IEVENT) & FEC_ENET_MII)) {
                cpu_relax();
                if (timeout-- < 0) {
                        fep->mii_timeout = 1;
                        printk(KERN_ERR "FEC: MDIO write timeout\n");
                        return -ETIMEDOUT;
                }
        }

        return 0;
}

static int fec_enet_mdio_reset(struct mii_bus *bus)
{
        return 0;
}

static int fec_enet_mii_probe(struct net_device *dev)
{
        struct fec_enet_private *fep = netdev_priv(dev);
        struct phy_device *phy_dev = NULL;
        int ret;

        fep->phy_dev = NULL;

        /* find the first phy */
        phy_dev = phy_find_first(fep->mii_bus);
        if (!phy_dev) {
                printk(KERN_ERR "%s: no PHY found\n", dev->name);
                return -ENODEV;
        }

        /* attach the mac to the phy */
        ret = phy_connect_direct(dev, phy_dev,
                             &fec_enet_adjust_link, 0,
                             PHY_INTERFACE_MODE_MII);
        if (ret) {
                printk(KERN_ERR "%s: Could not attach to PHY\n", dev->name);
                return ret;
        }

        /* mask with MAC supported features */
        phy_dev->supported &= PHY_BASIC_FEATURES;
        phy_dev->advertising = phy_dev->supported;

        fep->phy_dev = phy_dev;
        fep->link = 0;
        fep->full_duplex = 0;

        printk(KERN_INFO "%s: Freescale FEC PHY driver [%s] "
                "(mii_bus:phy_addr=%s, irq=%d)\n", dev->name,
                fep->phy_dev->drv->name, dev_name(&fep->phy_dev->dev),
                fep->phy_dev->irq);

        return 0;
}

static int fec_enet_mii_init(struct platform_device *pdev)
{
        struct net_device *dev = platform_get_drvdata(pdev);
        struct fec_enet_private *fep = netdev_priv(dev);
        int err = -ENXIO, i;

        fep->mii_timeout = 0;

        /*
         * Set MII speed to 2.5 MHz (= clk_get_rate() / 2 * phy_speed)
         */
        fep->phy_speed = DIV_ROUND_UP(clk_get_rate(fep->clk), 5000000) << 1;
        writel(fep->phy_speed, fep->hwp + FEC_MII_SPEED);

        fep->mii_bus = mdiobus_alloc();
        if (fep->mii_bus == NULL) {
                err = -ENOMEM;
                goto err_out;
        }

        fep->mii_bus->name = "fec_enet_mii_bus";
        fep->mii_bus->read = fec_enet_mdio_read;
        fep->mii_bus->write = fec_enet_mdio_write;
        fep->mii_bus->reset = fec_enet_mdio_reset;
        snprintf(fep->mii_bus->id, MII_BUS_ID_SIZE, "%x", pdev->id);
        fep->mii_bus->priv = fep;
        fep->mii_bus->parent = &pdev->dev;

        fep->mii_bus->irq = kmalloc(sizeof(int) * PHY_MAX_ADDR, GFP_KERNEL);
        if (!fep->mii_bus->irq) {
                err = -ENOMEM;
                goto err_out_free_mdiobus;
        }

        for (i = 0; i < PHY_MAX_ADDR; i++)
                fep->mii_bus->irq[i] = PHY_POLL;

        platform_set_drvdata(dev, fep->mii_bus);

        if (mdiobus_register(fep->mii_bus))
                goto err_out_free_mdio_irq;

        return 0;

err_out_free_mdio_irq:
        kfree(fep->mii_bus->irq);
err_out_free_mdiobus:
        mdiobus_free(fep->mii_bus);
err_out:
        return err;
}

static void fec_enet_mii_remove(struct fec_enet_private *fep)
{
        if (fep->phy_dev)
                phy_disconnect(fep->phy_dev);
        mdiobus_unregister(fep->mii_bus);
        kfree(fep->mii_bus->irq);
        mdiobus_free(fep->mii_bus);
}

static int fec_enet_get_settings(struct net_device *dev,
                                  struct ethtool_cmd *cmd)
{
        struct fec_enet_private *fep = netdev_priv(dev);
        struct phy_device *phydev = fep->phy_dev;

        if (!phydev)
                return -ENODEV;

        return phy_ethtool_gset(phydev, cmd);
}

static int fec_enet_set_settings(struct net_device *dev,
                                 struct ethtool_cmd *cmd)
{
        struct fec_enet_private *fep = netdev_priv(dev);
        struct phy_device *phydev = fep->phy_dev;

        if (!phydev)
                return -ENODEV;

        return phy_ethtool_sset(phydev, cmd);
}

static void fec_enet_get_drvinfo(struct net_device *dev,
                                 struct ethtool_drvinfo *info)
{
        struct fec_enet_private *fep = netdev_priv(dev);

        strcpy(info->driver, fep->pdev->dev.driver->name);
        strcpy(info->version, "Revision: 1.0");
        strcpy(info->bus_info, dev_name(&dev->dev));
}

static struct ethtool_ops fec_enet_ethtool_ops = {
        .get_settings           = fec_enet_get_settings,
        .set_settings           = fec_enet_set_settings,
        .get_drvinfo            = fec_enet_get_drvinfo,
        .get_link               = ethtool_op_get_link,
};

static int fec_enet_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
{
        struct fec_enet_private *fep = netdev_priv(dev);
        struct phy_device *phydev = fep->phy_dev;

        if (!netif_running(dev))
                return -EINVAL;

        if (!phydev)
                return -ENODEV;

        return phy_mii_ioctl(phydev, if_mii(rq), cmd);
}

static void fec_enet_free_buffers(struct net_device *dev)
{
        struct fec_enet_private *fep = netdev_priv(dev);
        int i;
        struct sk_buff *skb;
        struct bufdesc  *bdp;

        bdp = fep->rx_bd_base;
        for (i = 0; i < RX_RING_SIZE; i++) {
                skb = fep->rx_skbuff[i];

                if (bdp->cbd_bufaddr)
                        dma_unmap_single(&dev->dev, bdp->cbd_bufaddr,
                                        FEC_ENET_RX_FRSIZE, DMA_FROM_DEVICE);
                if (skb)
                        dev_kfree_skb(skb);
                bdp++;
        }

        bdp = fep->tx_bd_base;
        for (i = 0; i < TX_RING_SIZE; i++)
                kfree(fep->tx_bounce[i]);
}

static int fec_enet_alloc_buffers(struct net_device *dev)
{
        struct fec_enet_private *fep = netdev_priv(dev);
        int i;
        struct sk_buff *skb;
        struct bufdesc  *bdp;

        bdp = fep->rx_bd_base;
        for (i = 0; i < RX_RING_SIZE; i++) {
                skb = dev_alloc_skb(FEC_ENET_RX_FRSIZE);
                if (!skb) {
                        fec_enet_free_buffers(dev);
                        return -ENOMEM;
                }
                fep->rx_skbuff[i] = skb;

                bdp->cbd_bufaddr = dma_map_single(&dev->dev, skb->data,
                                FEC_ENET_RX_FRSIZE, DMA_FROM_DEVICE);
                bdp->cbd_sc = BD_ENET_RX_EMPTY;
                bdp++;
        }

        /* Set the last buffer to wrap. */
        bdp--;
        bdp->cbd_sc |= BD_SC_WRAP;

        bdp = fep->tx_bd_base;
        for (i = 0; i < TX_RING_SIZE; i++) {
                fep->tx_bounce[i] = kmalloc(FEC_ENET_TX_FRSIZE, GFP_KERNEL);

                bdp->cbd_sc = 0;
                bdp->cbd_bufaddr = 0;
                bdp++;
        }

        /* Set the last buffer to wrap. */
        bdp--;
        bdp->cbd_sc |= BD_SC_WRAP;

        return 0;
}

static int
fec_enet_open(struct net_device *dev)
{
        struct fec_enet_private *fep = netdev_priv(dev);
        int ret;

        /* I should reset the ring buffers here, but I don't yet know
         * a simple way to do that.
         */

        ret = fec_enet_alloc_buffers(dev);
        if (ret)
                return ret;

        /* Probe and connect to PHY when open the interface */
        ret = fec_enet_mii_probe(dev);
        if (ret) {
                fec_enet_free_buffers(dev);
                return ret;
        }
        phy_start(fep->phy_dev);
        netif_start_queue(dev);
        fep->opened = 1;
        return 0;
}

static int
fec_enet_close(struct net_device *dev)
{
        struct fec_enet_private *fep = netdev_priv(dev);

        /* Don't know what to do yet. */
        fep->opened = 0;
        netif_stop_queue(dev);
        fec_stop(dev);

        if (fep->phy_dev)
                phy_disconnect(fep->phy_dev);

        fec_enet_free_buffers(dev);

        return 0;
}

/* Set or clear the multicast filter for this adaptor.
 * Skeleton taken from sunlance driver.
 * The CPM Ethernet implementation allows Multicast as well as individual
 * MAC address filtering.  Some of the drivers check to make sure it is
 * a group multicast address, and discard those that are not.  I guess I
 * will do the same for now, but just remove the test if you want
 * individual filtering as well (do the upper net layers want or support
 * this kind of feature?).
 */

#define HASH_BITS       6               /* #bits in hash */
#define CRC32_POLY      0xEDB88320

static void set_multicast_list(struct net_device *dev)
{
        struct fec_enet_private *fep = netdev_priv(dev);
        struct netdev_hw_addr *ha;
        unsigned int i, bit, data, crc, tmp;
        unsigned char hash;

        if (dev->flags & IFF_PROMISC) {
                tmp = readl(fep->hwp + FEC_R_CNTRL);
                tmp |= 0x8;
                writel(tmp, fep->hwp + FEC_R_CNTRL);
                return;
        }

        tmp = readl(fep->hwp + FEC_R_CNTRL);
        tmp &= ~0x8;
        writel(tmp, fep->hwp + FEC_R_CNTRL);

        if (dev->flags & IFF_ALLMULTI) {
                /* Catch all multicast addresses, so set the
                 * filter to all 1's
                 */
                writel(0xffffffff, fep->hwp + FEC_GRP_HASH_TABLE_HIGH);
                writel(0xffffffff, fep->hwp + FEC_GRP_HASH_TABLE_LOW);

                return;
        }

        /* Clear filter and add the addresses in hash register
         */
        writel(0, fep->hwp + FEC_GRP_HASH_TABLE_HIGH);
        writel(0, fep->hwp + FEC_GRP_HASH_TABLE_LOW);

        netdev_for_each_mc_addr(ha, dev) {
                /* Only support group multicast for now */
                if (!(ha->addr[0] & 1))
                        continue;

                /* calculate crc32 value of mac address */
                crc = 0xffffffff;

                for (i = 0; i < dev->addr_len; i++) {
                        data = ha->addr[i];
                        for (bit = 0; bit < 8; bit++, data >>= 1) {
                                crc = (crc >> 1) ^
                                (((crc ^ data) & 1) ? CRC32_POLY : 0);
                        }
                }

                /* only upper 6 bits (HASH_BITS) are used
                 * which point to specific bit in he hash registers
                 */
                hash = (crc >> (32 - HASH_BITS)) & 0x3f;

                if (hash > 31) {
                        tmp = readl(fep->hwp + FEC_GRP_HASH_TABLE_HIGH);
                        tmp |= 1 << (hash - 32);
                        writel(tmp, fep->hwp + FEC_GRP_HASH_TABLE_HIGH);
                } else {
                        tmp = readl(fep->hwp + FEC_GRP_HASH_TABLE_LOW);
                        tmp |= 1 << hash;
                        writel(tmp, fep->hwp + FEC_GRP_HASH_TABLE_LOW);
                }
        }
}

/* Set a MAC change in hardware. */
static int
fec_set_mac_address(struct net_device *dev, void *p)
{
        struct fec_enet_private *fep = netdev_priv(dev);
        struct sockaddr *addr = p;

        if (!is_valid_ether_addr(addr->sa_data))
                return -EADDRNOTAVAIL;

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

        writel(dev->dev_addr[3] | (dev->dev_addr[2] << 8) |
                (dev->dev_addr[1] << 16) | (dev->dev_addr[0] << 24),
                fep->hwp + FEC_ADDR_LOW);
        writel((dev->dev_addr[5] << 16) | (dev->dev_addr[4] << 24),
                fep->hwp + FEC_ADDR_HIGH);
        return 0;
}

static const struct net_device_ops fec_netdev_ops = {
        .ndo_open               = fec_enet_open,
        .ndo_stop               = fec_enet_close,
        .ndo_start_xmit         = fec_enet_start_xmit,
        .ndo_set_multicast_list = set_multicast_list,
        .ndo_change_mtu         = eth_change_mtu,
        .ndo_validate_addr      = eth_validate_addr,
        .ndo_tx_timeout         = fec_timeout,
        .ndo_set_mac_address    = fec_set_mac_address,
        .ndo_do_ioctl           = fec_enet_ioctl,
};

 /*
  * XXX:  We need to clean up on failure exits here.
  *
  * index is only used in legacy code
  */
static int fec_enet_init(struct net_device *dev, int index)
{
        struct fec_enet_private *fep = netdev_priv(dev);
        struct bufdesc *cbd_base;
        struct bufdesc *bdp;
        int i;

        /* Allocate memory for buffer descriptors. */
        cbd_base = dma_alloc_coherent(NULL, PAGE_SIZE, &fep->bd_dma,
                        GFP_KERNEL);
        if (!cbd_base) {
                printk("FEC: allocate descriptor memory failed?\n");
                return -ENOMEM;
        }

        spin_lock_init(&fep->hw_lock);

        fep->index = index;
        fep->hwp = (void __iomem *)dev->base_addr;
        fep->netdev = dev;

        /* Set the Ethernet address */
#ifdef CONFIG_M5272
        fec_get_mac(dev);
#else
        {
                unsigned long l;
                l = readl(fep->hwp + FEC_ADDR_LOW);
                dev->dev_addr[0] = (unsigned char)((l & 0xFF000000) >> 24);
                dev->dev_addr[1] = (unsigned char)((l & 0x00FF0000) >> 16);
                dev->dev_addr[2] = (unsigned char)((l & 0x0000FF00) >> 8);
                dev->dev_addr[3] = (unsigned char)((l & 0x000000FF) >> 0);
                l = readl(fep->hwp + FEC_ADDR_HIGH);
                dev->dev_addr[4] = (unsigned char)((l & 0xFF000000) >> 24);
                dev->dev_addr[5] = (unsigned char)((l & 0x00FF0000) >> 16);
        }
#endif

        /* Set receive and transmit descriptor base. */
        fep->rx_bd_base = cbd_base;
        fep->tx_bd_base = cbd_base + RX_RING_SIZE;

        /* The FEC Ethernet specific entries in the device structure */
        dev->watchdog_timeo = TX_TIMEOUT;
        dev->netdev_ops = &fec_netdev_ops;
        dev->ethtool_ops = &fec_enet_ethtool_ops;

        /* Initialize the receive buffer descriptors. */
        bdp = fep->rx_bd_base;
        for (i = 0; i < RX_RING_SIZE; i++) {

                /* Initialize the BD for every fragment in the page. */
                bdp->cbd_sc = 0;
                bdp++;
        }

        /* Set the last buffer to wrap */
        bdp--;
        bdp->cbd_sc |= BD_SC_WRAP;

        /* ...and the same for transmit */
        bdp = fep->tx_bd_base;
        for (i = 0; i < TX_RING_SIZE; i++) {

                /* Initialize the BD for every fragment in the page. */
                bdp->cbd_sc = 0;
                bdp->cbd_bufaddr = 0;
                bdp++;
        }

        /* Set the last buffer to wrap */
        bdp--;
        bdp->cbd_sc |= BD_SC_WRAP;

        fec_restart(dev, 0);

        return 0;
}

/* This function is called to start or restart the FEC during a link
 * change.  This only happens when switching between half and full
 * duplex.
 */
static void
fec_restart(struct net_device *dev, int duplex)
{
        struct fec_enet_private *fep = netdev_priv(dev);
        int i;

        /* Whack a reset.  We should wait for this. */
        writel(1, fep->hwp + FEC_ECNTRL);
        udelay(10);

        /* Clear any outstanding interrupt. */
        writel(0xffc00000, fep->hwp + FEC_IEVENT);

        /* Reset all multicast. */
        writel(0, fep->hwp + FEC_GRP_HASH_TABLE_HIGH);
        writel(0, fep->hwp + FEC_GRP_HASH_TABLE_LOW);
#ifndef CONFIG_M5272
        writel(0, fep->hwp + FEC_HASH_TABLE_HIGH);
        writel(0, fep->hwp + FEC_HASH_TABLE_LOW);
#endif

        /* Set maximum receive buffer size. */
        writel(PKT_MAXBLR_SIZE, fep->hwp + FEC_R_BUFF_SIZE);

        /* Set receive and transmit descriptor base. */
        writel(fep->bd_dma, fep->hwp + FEC_R_DES_START);
        writel((unsigned long)fep->bd_dma + sizeof(struct bufdesc) * RX_RING_SIZE,
                        fep->hwp + FEC_X_DES_START);

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

        /* Reset SKB transmit buffers. */
        fep->skb_cur = fep->skb_dirty = 0;
        for (i = 0; i <= TX_RING_MOD_MASK; i++) {
                if (fep->tx_skbuff[i]) {
                        dev_kfree_skb_any(fep->tx_skbuff[i]);
                        fep->tx_skbuff[i] = NULL;
                }
        }

        /* Enable MII mode */
        if (duplex) {
                /* MII enable / FD enable */
                writel(OPT_FRAME_SIZE | 0x04, fep->hwp + FEC_R_CNTRL);
                writel(0x04, fep->hwp + FEC_X_CNTRL);
        } else {
                /* MII enable / No Rcv on Xmit */
                writel(OPT_FRAME_SIZE | 0x06, fep->hwp + FEC_R_CNTRL);
                writel(0x0, fep->hwp + FEC_X_CNTRL);
        }
        fep->full_duplex = duplex;

        /* Set MII speed */
        writel(fep->phy_speed, fep->hwp + FEC_MII_SPEED);

#ifdef FEC_MIIGSK_ENR
        if (fep->phy_interface == PHY_INTERFACE_MODE_RMII) {
                /* disable the gasket and wait */
                writel(0, fep->hwp + FEC_MIIGSK_ENR);
                while (readl(fep->hwp + FEC_MIIGSK_ENR) & 4)
                        udelay(1);

                /* configure the gasket: RMII, 50 MHz, no loopback, no echo */
                writel(1, fep->hwp + FEC_MIIGSK_CFGR);

                /* re-enable the gasket */
                writel(2, fep->hwp + FEC_MIIGSK_ENR);
        }
#endif

        /* And last, enable the transmit and receive processing */
        writel(2, fep->hwp + FEC_ECNTRL);
        writel(0, fep->hwp + FEC_R_DES_ACTIVE);

        /* Enable interrupts we wish to service */
        writel(FEC_ENET_TXF | FEC_ENET_RXF, fep->hwp + FEC_IMASK);
}

static void
fec_stop(struct net_device *dev)
{
        struct fec_enet_private *fep = netdev_priv(dev);

        /* We cannot expect a graceful transmit stop without link !!! */
        if (fep->link) {
                writel(1, fep->hwp + FEC_X_CNTRL); /* Graceful transmit stop */
                udelay(10);
                if (!(readl(fep->hwp + FEC_IEVENT) & FEC_ENET_GRA))
                        printk("fec_stop : Graceful transmit stop did not complete !\n");
        }

        /* Whack a reset.  We should wait for this. */
        writel(1, fep->hwp + FEC_ECNTRL);
        udelay(10);

        /* Clear outstanding MII command interrupts. */
        writel(FEC_ENET_MII, fep->hwp + FEC_IEVENT);

        writel(fep->phy_speed, fep->hwp + FEC_MII_SPEED);
}

static int __devinit
fec_probe(struct platform_device *pdev)
{
        struct fec_enet_private *fep;
        struct fec_platform_data *pdata;
        struct net_device *ndev;
        int i, irq, ret = 0;
        struct resource *r;

        r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (!r)
                return -ENXIO;

        r = request_mem_region(r->start, resource_size(r), pdev->name);
        if (!r)
                return -EBUSY;

        /* Init network device */
        ndev = alloc_etherdev(sizeof(struct fec_enet_private));
        if (!ndev)
                return -ENOMEM;

        SET_NETDEV_DEV(ndev, &pdev->dev);

        /* setup board info structure */
        fep = netdev_priv(ndev);
        memset(fep, 0, sizeof(*fep));

        ndev->base_addr = (unsigned long)ioremap(r->start, resource_size(r));
        fep->pdev = pdev;

        if (!ndev->base_addr) {
                ret = -ENOMEM;
                goto failed_ioremap;
        }

        platform_set_drvdata(pdev, ndev);

        pdata = pdev->dev.platform_data;
        if (pdata)
                fep->phy_interface = pdata->phy;

        /* This device has up to three irqs on some platforms */
        for (i = 0; i < 3; i++) {
                irq = platform_get_irq(pdev, i);
                if (i && irq < 0)
                        break;
                ret = request_irq(irq, fec_enet_interrupt, IRQF_DISABLED, pdev->name, ndev);
                if (ret) {
                        while (i >= 0) {
                                irq = platform_get_irq(pdev, i);
                                free_irq(irq, ndev);
                                i--;
                        }
                        goto failed_irq;
                }
        }

        fep->clk = clk_get(&pdev->dev, "fec_clk");
        if (IS_ERR(fep->clk)) {
                ret = PTR_ERR(fep->clk);
                goto failed_clk;
        }
        clk_enable(fep->clk);

        ret = fec_enet_init(ndev, 0);
        if (ret)
                goto failed_init;

        ret = fec_enet_mii_init(pdev);
        if (ret)
                goto failed_mii_init;

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

        return 0;

failed_register:
        fec_enet_mii_remove(fep);
failed_mii_init:
failed_init:
        clk_disable(fep->clk);
        clk_put(fep->clk);
failed_clk:
        for (i = 0; i < 3; i++) {
                irq = platform_get_irq(pdev, i);
                if (irq > 0)
                        free_irq(irq, ndev);
        }
failed_irq:
        iounmap((void __iomem *)ndev->base_addr);
failed_ioremap:
        free_netdev(ndev);

        return ret;
}

static int __devexit
fec_drv_remove(struct platform_device *pdev)
{
        struct net_device *ndev = platform_get_drvdata(pdev);
        struct fec_enet_private *fep = netdev_priv(ndev);

        platform_set_drvdata(pdev, NULL);

        fec_stop(ndev);
        fec_enet_mii_remove(fep);
        clk_disable(fep->clk);
        clk_put(fep->clk);
        iounmap((void __iomem *)ndev->base_addr);
        unregister_netdev(ndev);
        free_netdev(ndev);
        return 0;
}

#ifdef CONFIG_PM
static int
fec_suspend(struct device *dev)
{
        struct net_device *ndev = dev_get_drvdata(dev);
        struct fec_enet_private *fep;

        if (ndev) {
                fep = netdev_priv(ndev);
                if (netif_running(ndev))
                        fec_enet_close(ndev);
                clk_disable(fep->clk);
        }
        return 0;
}

static int
fec_resume(struct device *dev)
{
        struct net_device *ndev = dev_get_drvdata(dev);
        struct fec_enet_private *fep;

        if (ndev) {
                fep = netdev_priv(ndev);
                clk_enable(fep->clk);
                if (netif_running(ndev))
                        fec_enet_open(ndev);
        }
        return 0;
}

static const struct dev_pm_ops fec_pm_ops = {
        .suspend        = fec_suspend,
        .resume         = fec_resume,
        .freeze         = fec_suspend,
        .thaw           = fec_resume,
        .poweroff       = fec_suspend,
        .restore        = fec_resume,
};
#endif

static struct platform_driver fec_driver = {
        .driver = {
                .name   = "fec",
                .owner  = THIS_MODULE,
#ifdef CONFIG_PM
                .pm     = &fec_pm_ops,
#endif
        },
        .probe  = fec_probe,
        .remove = __devexit_p(fec_drv_remove),
};

static int __init
fec_enet_module_init(void)
{
        printk(KERN_INFO "FEC Ethernet Driver\n");

        return platform_driver_register(&fec_driver);
}

static void __exit
fec_enet_cleanup(void)
{
        platform_driver_unregister(&fec_driver);
}

module_exit(fec_enet_cleanup);
module_init(fec_enet_module_init);

MODULE_LICENSE("GPL");