[PATCH] ocfs2: zero_user_page conversion

[wrt350n-kernel.git] / arch / ppc / 8xx_io / fec.c

/*
 * Fast Ethernet Controller (FEC) driver for Motorola MPC8xx.
 * Copyright (c) 1997 Dan Malek (dmalek@jlc.net)
 *
 * This version of the driver is specific to the FADS implementation,
 * since the board contains control registers external to the processor
 * for the control of the LevelOne LXT970 transceiver.  The MPC860T manual
 * describes connections using the internal parallel port I/O, which
 * is basically all of Port D.
 *
 * Includes support for the following PHYs: QS6612, LXT970, LXT971/2.
 *
 * 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.
 *
 * Make use of MII for PHY control configurable.
 * Some fixes.
 * Copyright (c) 2000-2002 Wolfgang Denk, DENX Software Engineering.
 *
 * Support for AMD AM79C874 added.
 * Thomas Lange, thomas@corelatus.com
 */

#include <linux/kernel.h>
#include <linux/sched.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/bitops.h>
#ifdef CONFIG_FEC_PACKETHOOK
#include <linux/pkthook.h>
#endif

#include <asm/8xx_immap.h>
#include <asm/pgtable.h>
#include <asm/mpc8xx.h>
#include <asm/irq.h>
#include <asm/uaccess.h>
#include <asm/commproc.h>

#ifdef  CONFIG_USE_MDIO
/* Forward declarations of some structures to support different PHYs
*/

typedef struct {
        uint mii_data;
        void (*funct)(uint mii_reg, struct net_device *dev);
} phy_cmd_t;

typedef struct {
        uint id;
        char *name;

        const phy_cmd_t *config;
        const phy_cmd_t *startup;
        const phy_cmd_t *ack_int;
        const phy_cmd_t *shutdown;
} phy_info_t;
#endif  /* CONFIG_USE_MDIO */

/* 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 is best
 * to keep them that size.
 * We don't need to allocate pages for the transmitter.  We just use
 * the skbuffer directly.
 */
#ifdef CONFIG_ENET_BIG_BUFFERS
#define FEC_ENET_RX_PAGES       16
#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 TX_RING_SIZE            16      /* Must be power of two */
#define TX_RING_MOD_MASK        15      /*   for this to work */
#else
#define FEC_ENET_RX_PAGES       4
#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 TX_RING_SIZE            8       /* Must be power of two */
#define TX_RING_MOD_MASK        7       /*   for this to work */
#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 */

/*
*/
#define FEC_ECNTRL_PINMUX       0x00000004
#define FEC_ECNTRL_ETHER_EN     0x00000002
#define FEC_ECNTRL_RESET        0x00000001

#define FEC_RCNTRL_BC_REJ       0x00000010
#define FEC_RCNTRL_PROM         0x00000008
#define FEC_RCNTRL_MII_MODE     0x00000004
#define FEC_RCNTRL_DRT          0x00000002
#define FEC_RCNTRL_LOOP         0x00000001

#define FEC_TCNTRL_FDEN         0x00000004
#define FEC_TCNTRL_HBC          0x00000002
#define FEC_TCNTRL_GTS          0x00000001

/* Delay to wait for FEC reset command to complete (in us)
*/
#define FEC_RESET_DELAY         50

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

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

        /* Virtual addresses for the receive buffers because we can't
         * do a __va() on them anymore.
         */
        unsigned char *rx_vaddr[RX_RING_SIZE];

        struct  net_device_stats stats;
        uint    tx_full;
        spinlock_t lock;

#ifdef  CONFIG_USE_MDIO
        uint    phy_id;
        uint    phy_id_done;
        uint    phy_status;
        uint    phy_speed;
        phy_info_t      *phy;
        struct work_struct phy_task;
        struct net_device *dev;

        uint    sequence_done;

        uint    phy_addr;
#endif  /* CONFIG_USE_MDIO */

        int     link;
        int     old_link;
        int     full_duplex;

#ifdef CONFIG_FEC_PACKETHOOK
        unsigned long   ph_lock;
        fec_ph_func     *ph_rxhandler;
        fec_ph_func     *ph_txhandler;
        __u16           ph_proto;
        volatile __u32  *ph_regaddr;
        void            *ph_priv;
#endif
};

static int fec_enet_open(struct net_device *dev);
static int fec_enet_start_xmit(struct sk_buff *skb, struct net_device *dev);
#ifdef  CONFIG_USE_MDIO
static void fec_enet_mii(struct net_device *dev);
#endif  /* CONFIG_USE_MDIO */
static irqreturn_t fec_enet_interrupt(int irq, void * dev_id);
#ifdef CONFIG_FEC_PACKETHOOK
static void  fec_enet_tx(struct net_device *dev, __u32 regval);
static void  fec_enet_rx(struct net_device *dev, __u32 regval);
#else
static void  fec_enet_tx(struct net_device *dev);
static void  fec_enet_rx(struct net_device *dev);
#endif
static int fec_enet_close(struct net_device *dev);
static struct net_device_stats *fec_enet_get_stats(struct net_device *dev);
static void set_multicast_list(struct net_device *dev);
static void fec_restart(struct net_device *dev, int duplex);
static void fec_stop(struct net_device *dev);
static  ushort  my_enet_addr[3];

#ifdef  CONFIG_USE_MDIO
/* MII processing.  We keep this as simple as possible.  Requests are
 * placed on the list (if there is room).  When the request is finished
 * by the MII, an optional function may be called.
 */
typedef struct mii_list {
        uint    mii_regval;
        void    (*mii_func)(uint val, struct net_device *dev);
        struct  mii_list *mii_next;
} mii_list_t;

#define         NMII    20
mii_list_t      mii_cmds[NMII];
mii_list_t      *mii_free;
mii_list_t      *mii_head;
mii_list_t      *mii_tail;

static int      mii_queue(struct net_device *dev, int request,
                                void (*func)(uint, struct net_device *));

/* Make MII read/write commands for the FEC.
*/
#define mk_mii_read(REG)        (0x60020000 | ((REG & 0x1f) << 18))
#define mk_mii_write(REG, VAL)  (0x50020000 | ((REG & 0x1f) << 18) | \
                                                (VAL & 0xffff))
#define mk_mii_end      0
#endif  /* CONFIG_USE_MDIO */

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

#ifdef  CONFIG_USE_MDIO
/* Register definitions for the PHY.
*/

#define MII_REG_CR          0  /* Control Register                         */
#define MII_REG_SR          1  /* Status Register                          */
#define MII_REG_PHYIR1      2  /* PHY Identification Register 1            */
#define MII_REG_PHYIR2      3  /* PHY Identification Register 2            */
#define MII_REG_ANAR        4  /* A-N Advertisement Register               */
#define MII_REG_ANLPAR      5  /* A-N Link Partner Ability Register        */
#define MII_REG_ANER        6  /* A-N Expansion Register                   */
#define MII_REG_ANNPTR      7  /* A-N Next Page Transmit Register          */
#define MII_REG_ANLPRNPR    8  /* A-N Link Partner Received Next Page Reg. */

/* values for phy_status */

#define PHY_CONF_ANE    0x0001  /* 1 auto-negotiation enabled */
#define PHY_CONF_LOOP   0x0002  /* 1 loopback mode enabled */
#define PHY_CONF_SPMASK 0x00f0  /* mask for speed */
#define PHY_CONF_10HDX  0x0010  /* 10 Mbit half duplex supported */
#define PHY_CONF_10FDX  0x0020  /* 10 Mbit full duplex supported */
#define PHY_CONF_100HDX 0x0040  /* 100 Mbit half duplex supported */
#define PHY_CONF_100FDX 0x0080  /* 100 Mbit full duplex supported */

#define PHY_STAT_LINK   0x0100  /* 1 up - 0 down */
#define PHY_STAT_FAULT  0x0200  /* 1 remote fault */
#define PHY_STAT_ANC    0x0400  /* 1 auto-negotiation complete  */
#define PHY_STAT_SPMASK 0xf000  /* mask for speed */
#define PHY_STAT_10HDX  0x1000  /* 10 Mbit half duplex selected */
#define PHY_STAT_10FDX  0x2000  /* 10 Mbit full duplex selected */
#define PHY_STAT_100HDX 0x4000  /* 100 Mbit half duplex selected */
#define PHY_STAT_100FDX 0x8000  /* 100 Mbit full duplex selected */
#endif  /* CONFIG_USE_MDIO */

#ifdef CONFIG_FEC_PACKETHOOK
int
fec_register_ph(struct net_device *dev, fec_ph_func *rxfun, fec_ph_func *txfun,
                __u16 proto, volatile __u32 *regaddr, void *priv)
{
        struct fec_enet_private *fep;
        int retval = 0;

        fep = dev->priv;

        if (test_and_set_bit(0, (void*)&fep->ph_lock) != 0) {
                /* Someone is messing with the packet hook */
                return -EAGAIN;
        }
        if (fep->ph_rxhandler != NULL || fep->ph_txhandler != NULL) {
                retval = -EBUSY;
                goto out;
        }
        fep->ph_rxhandler = rxfun;
        fep->ph_txhandler = txfun;
        fep->ph_proto = proto;
        fep->ph_regaddr = regaddr;
        fep->ph_priv = priv;

        out:
        fep->ph_lock = 0;

        return retval;
}


int
fec_unregister_ph(struct net_device *dev)
{
        struct fec_enet_private *fep;
        int retval = 0;

        fep = dev->priv;

        if (test_and_set_bit(0, (void*)&fep->ph_lock) != 0) {
                /* Someone is messing with the packet hook */
                return -EAGAIN;
        }

        fep->ph_rxhandler = fep->ph_txhandler = NULL;
        fep->ph_proto = 0;
        fep->ph_regaddr = NULL;
        fep->ph_priv = NULL;

        fep->ph_lock = 0;

        return retval;
}

EXPORT_SYMBOL(fec_register_ph);
EXPORT_SYMBOL(fec_unregister_ph);

#endif /* CONFIG_FEC_PACKETHOOK */

static int
fec_enet_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
        struct fec_enet_private *fep;
        volatile fec_t  *fecp;
        volatile cbd_t  *bdp;

        fep = dev->priv;
        fecp = (volatile fec_t*)dev->base_addr;

        if (!fep->link) {
                /* Link is down or autonegotiation is in progress. */
                return 1;
        }

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

#ifndef final_version
        if (bdp->cbd_sc & 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);
                return 1;
        }
#endif

        /* Clear all of the status flags.
         */
        bdp->cbd_sc &= ~BD_ENET_TX_STATS;

        /* Set buffer length and buffer pointer.
        */
        bdp->cbd_bufaddr = __pa(skb->data);
        bdp->cbd_datlen = skb->len;

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

        fep->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.
         */
        flush_dcache_range((unsigned long)skb->data,
                           (unsigned long)skb->data + skb->len);

        /* disable interrupts while triggering transmit */
        spin_lock_irq(&fep->lock);

        /* Send it on its way.  Tell FEC its ready, interrupt when done,
         * its the last BD of the frame, and to put the CRC on the end.
         */

        bdp->cbd_sc |= (BD_ENET_TX_READY | BD_ENET_TX_INTR
                        | BD_ENET_TX_LAST | BD_ENET_TX_TC);

        dev->trans_start = jiffies;

        /* Trigger transmission start */
        fecp->fec_x_des_active = 0x01000000;

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

        if (bdp->cbd_sc & BD_ENET_TX_READY) {
                netif_stop_queue(dev);
                fep->tx_full = 1;
        }

        fep->cur_tx = (cbd_t *)bdp;

        spin_unlock_irq(&fep->lock);

        return 0;
}

static void
fec_timeout(struct net_device *dev)
{
        struct fec_enet_private *fep = dev->priv;

        printk("%s: transmit timed out.\n", dev->name);
        fep->stats.tx_errors++;
#ifndef final_version
        {
        int     i;
        cbd_t   *bdp;

        printk("Ring data dump: cur_tx %lx%s, dirty_tx %lx cur_rx: %lx\n",
               (unsigned long)fep->cur_tx, fep->tx_full ? " (full)" : "",
               (unsigned long)fep->dirty_tx,
               (unsigned long)fep->cur_rx);

        bdp = fep->tx_bd_base;
        printk(" tx: %u buffers\n",  TX_RING_SIZE);
        for (i = 0 ; i < TX_RING_SIZE; i++) {
                printk("  %08x: %04x %04x %08x\n",
                       (uint) bdp,
                       bdp->cbd_sc,
                       bdp->cbd_datlen,
                       bdp->cbd_bufaddr);
                bdp++;
        }

        bdp = fep->rx_bd_base;
        printk(" rx: %lu buffers\n",  RX_RING_SIZE);
        for (i = 0 ; i < RX_RING_SIZE; i++) {
                printk("  %08x: %04x %04x %08x\n",
                       (uint) bdp,
                       bdp->cbd_sc,
                       bdp->cbd_datlen,
                       bdp->cbd_bufaddr);
                bdp++;
        }
        }
#endif
        if (!fep->tx_full)
                netif_wake_queue(dev);
}

/* The interrupt handler.
 * This is called from the MPC core interrupt.
 */
static  irqreturn_t
fec_enet_interrupt(int irq, void * dev_id)
{
        struct  net_device *dev = dev_id;
        volatile fec_t  *fecp;
        uint    int_events;
#ifdef CONFIG_FEC_PACKETHOOK
        struct  fec_enet_private *fep = dev->priv;
        __u32 regval;

        if (fep->ph_regaddr) regval = *fep->ph_regaddr;
#endif
        fecp = (volatile fec_t*)dev->base_addr;

        /* Get the interrupt events that caused us to be here.
        */
        while ((int_events = fecp->fec_ievent) != 0) {
                fecp->fec_ievent = int_events;
                if ((int_events & (FEC_ENET_HBERR | FEC_ENET_BABR |
                                   FEC_ENET_BABT | FEC_ENET_EBERR)) != 0) {
                        printk("FEC ERROR %x\n", int_events);
                }

                /* Handle receive event in its own function.
                 */
                if (int_events & FEC_ENET_RXF) {
#ifdef CONFIG_FEC_PACKETHOOK
                        fec_enet_rx(dev, regval);
#else
                        fec_enet_rx(dev);
#endif
                }

                /* 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) {
#ifdef CONFIG_FEC_PACKETHOOK
                        fec_enet_tx(dev, regval);
#else
                        fec_enet_tx(dev);
#endif
                }

                if (int_events & FEC_ENET_MII) {
#ifdef  CONFIG_USE_MDIO
                        fec_enet_mii(dev);
#else
printk("%s[%d] %s: unexpected FEC_ENET_MII event\n", __FILE__,__LINE__,__FUNCTION__);
#endif  /* CONFIG_USE_MDIO */
                }

        }
        return IRQ_RETVAL(IRQ_HANDLED);
}


static void
#ifdef CONFIG_FEC_PACKETHOOK
fec_enet_tx(struct net_device *dev, __u32 regval)
#else
fec_enet_tx(struct net_device *dev)
#endif
{
        struct  fec_enet_private *fep;
        volatile cbd_t  *bdp;
        struct  sk_buff *skb;

        fep = dev->priv;
        /* lock while transmitting */
        spin_lock(&fep->lock);
        bdp = fep->dirty_tx;

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

                skb = fep->tx_skbuff[fep->skb_dirty];
                /* Check for errors. */
                if (bdp->cbd_sc & (BD_ENET_TX_HB | BD_ENET_TX_LC |
                                   BD_ENET_TX_RL | BD_ENET_TX_UN |
                                   BD_ENET_TX_CSL)) {
                        fep->stats.tx_errors++;
                        if (bdp->cbd_sc & BD_ENET_TX_HB)  /* No heartbeat */
                                fep->stats.tx_heartbeat_errors++;
                        if (bdp->cbd_sc & BD_ENET_TX_LC)  /* Late collision */
                                fep->stats.tx_window_errors++;
                        if (bdp->cbd_sc & BD_ENET_TX_RL)  /* Retrans limit */
                                fep->stats.tx_aborted_errors++;
                        if (bdp->cbd_sc & BD_ENET_TX_UN)  /* Underrun */
                                fep->stats.tx_fifo_errors++;
                        if (bdp->cbd_sc & BD_ENET_TX_CSL) /* Carrier lost */
                                fep->stats.tx_carrier_errors++;
                } else {
#ifdef CONFIG_FEC_PACKETHOOK
                        /* Packet hook ... */
                        if (fep->ph_txhandler &&
                            ((struct ethhdr *)skb->data)->h_proto
                            == fep->ph_proto) {
                                fep->ph_txhandler((__u8*)skb->data, skb->len,
                                                  regval, fep->ph_priv);
                        }
#endif
                        fep->stats.tx_packets++;
                }

#ifndef final_version
                if (bdp->cbd_sc & BD_ENET_TX_READY)
                        printk("HEY! Enet xmit interrupt and TX_READY.\n");
#endif
                /* Deferred means some collisions occurred during transmit,
                 * but we eventually sent the packet OK.
                 */
                if (bdp->cbd_sc & BD_ENET_TX_DEF)
                        fep->stats.collisions++;

                /* Free the sk buffer associated with this last transmit.
                 */
#if 0
printk("TXI: %x %x %x\n", bdp, skb, fep->skb_dirty);
#endif
                dev_kfree_skb_irq (skb/*, FREE_WRITE*/);
                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 (bdp->cbd_sc & 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);
                }
#ifdef CONFIG_FEC_PACKETHOOK
                /* Re-read register. Not exactly guaranteed to be correct,
                   but... */
                if (fep->ph_regaddr) regval = *fep->ph_regaddr;
#endif
        }
        fep->dirty_tx = (cbd_t *)bdp;
        spin_unlock(&fep->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
#ifdef CONFIG_FEC_PACKETHOOK
fec_enet_rx(struct net_device *dev, __u32 regval)
#else
fec_enet_rx(struct net_device *dev)
#endif
{
        struct  fec_enet_private *fep;
        volatile fec_t  *fecp;
        volatile cbd_t *bdp;
        struct  sk_buff *skb;
        ushort  pkt_len;
        __u8 *data;

        fep = dev->priv;
        fecp = (volatile fec_t*)dev->base_addr;

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

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

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

        /* Process the incoming frame.
         */
        fep->stats.rx_packets++;
        pkt_len = bdp->cbd_datlen;
        fep->stats.rx_bytes += pkt_len;
        data = fep->rx_vaddr[bdp - fep->rx_bd_base];

#ifdef CONFIG_FEC_PACKETHOOK
        /* Packet hook ... */
        if (fep->ph_rxhandler) {
                if (((struct ethhdr *)data)->h_proto == fep->ph_proto) {
                        switch (fep->ph_rxhandler(data, pkt_len, regval,
                                                  fep->ph_priv)) {
                        case 1:
                                goto rx_processing_done;
                                break;
                        case 0:
                                break;
                        default:
                                fep->stats.rx_errors++;
                                goto rx_processing_done;
                        }
                }
        }

        /* If it wasn't filtered - copy it to an sk buffer. */
#endif

        /* 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);

        if (skb == NULL) {
                printk("%s: Memory squeeze, dropping packet.\n", dev->name);
                fep->stats.rx_dropped++;
        } else {
                skb_put(skb,pkt_len-4); /* Make room */
                eth_copy_and_sum(skb, data, pkt_len-4, 0);
                skb->protocol=eth_type_trans(skb,dev);
                netif_rx(skb);
        }
  rx_processing_done:

        /* Clear the status flags for this buffer.
        */
        bdp->cbd_sc &= ~BD_ENET_RX_STATS;

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

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

#if 1
        /* 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.
         */
        fecp->fec_r_des_active = 0x01000000;
#endif
#ifdef CONFIG_FEC_PACKETHOOK
        /* Re-read register. Not exactly guaranteed to be correct,
           but... */
        if (fep->ph_regaddr) regval = *fep->ph_regaddr;
#endif
   } /* while (!(bdp->cbd_sc & BD_ENET_RX_EMPTY)) */
        fep->cur_rx = (cbd_t *)bdp;

#if 0
        /* Doing this here will allow us to process all frames in the
         * ring before the FEC is allowed to put more there.  On a heavily
         * loaded network, some frames may be lost.  Unfortunately, this
         * increases the interrupt overhead since we can potentially work
         * our way back to the interrupt return only to come right back
         * here.
         */
        fecp->fec_r_des_active = 0x01000000;
#endif
}


#ifdef  CONFIG_USE_MDIO
static void
fec_enet_mii(struct net_device *dev)
{
        struct  fec_enet_private *fep;
        volatile fec_t  *ep;
        mii_list_t      *mip;
        uint            mii_reg;

        fep = (struct fec_enet_private *)dev->priv;
        ep = &(((immap_t *)IMAP_ADDR)->im_cpm.cp_fec);
        mii_reg = ep->fec_mii_data;

        if ((mip = mii_head) == NULL) {
                printk("MII and no head!\n");
                return;
        }

        if (mip->mii_func != NULL)
                (*(mip->mii_func))(mii_reg, dev);

        mii_head = mip->mii_next;
        mip->mii_next = mii_free;
        mii_free = mip;

        if ((mip = mii_head) != NULL) {
                ep->fec_mii_data = mip->mii_regval;

        }
}

static int
mii_queue(struct net_device *dev, int regval, void (*func)(uint, struct net_device *))
{
        struct fec_enet_private *fep;
        unsigned long   flags;
        mii_list_t      *mip;
        int             retval;

        /* Add PHY address to register command.
        */
        fep = dev->priv;
        regval |= fep->phy_addr << 23;

        retval = 0;

        /* lock while modifying mii_list */
        spin_lock_irqsave(&fep->lock, flags);

        if ((mip = mii_free) != NULL) {
                mii_free = mip->mii_next;
                mip->mii_regval = regval;
                mip->mii_func = func;
                mip->mii_next = NULL;
                if (mii_head) {
                        mii_tail->mii_next = mip;
                        mii_tail = mip;
                } else {
                        mii_head = mii_tail = mip;
                        (&(((immap_t *)IMAP_ADDR)->im_cpm.cp_fec))->fec_mii_data = regval;
                }
        } else {
                retval = 1;
        }

        spin_unlock_irqrestore(&fep->lock, flags);

        return(retval);
}

static void mii_do_cmd(struct net_device *dev, const phy_cmd_t *c)
{
        int k;

        if(!c)
                return;

        for(k = 0; (c+k)->mii_data != mk_mii_end; k++)
                mii_queue(dev, (c+k)->mii_data, (c+k)->funct);
}

static void mii_parse_sr(uint mii_reg, struct net_device *dev)
{
        struct fec_enet_private *fep = dev->priv;
        volatile uint *s = &(fep->phy_status);

        *s &= ~(PHY_STAT_LINK | PHY_STAT_FAULT | PHY_STAT_ANC);

        if (mii_reg & 0x0004)
                *s |= PHY_STAT_LINK;
        if (mii_reg & 0x0010)
                *s |= PHY_STAT_FAULT;
        if (mii_reg & 0x0020)
                *s |= PHY_STAT_ANC;

        fep->link = (*s & PHY_STAT_LINK) ? 1 : 0;
}

static void mii_parse_cr(uint mii_reg, struct net_device *dev)
{
        struct fec_enet_private *fep = dev->priv;
        volatile uint *s = &(fep->phy_status);

        *s &= ~(PHY_CONF_ANE | PHY_CONF_LOOP);

        if (mii_reg & 0x1000)
                *s |= PHY_CONF_ANE;
        if (mii_reg & 0x4000)
                *s |= PHY_CONF_LOOP;
}

static void mii_parse_anar(uint mii_reg, struct net_device *dev)
{
        struct fec_enet_private *fep = dev->priv;
        volatile uint *s = &(fep->phy_status);

        *s &= ~(PHY_CONF_SPMASK);

        if (mii_reg & 0x0020)
                *s |= PHY_CONF_10HDX;
        if (mii_reg & 0x0040)
                *s |= PHY_CONF_10FDX;
        if (mii_reg & 0x0080)
                *s |= PHY_CONF_100HDX;
        if (mii_reg & 0x00100)
                *s |= PHY_CONF_100FDX;
}
#if 0
static void mii_disp_reg(uint mii_reg, struct net_device *dev)
{
        printk("reg %u = 0x%04x\n", (mii_reg >> 18) & 0x1f, mii_reg & 0xffff);
}
#endif

/* ------------------------------------------------------------------------- */
/* The Level one LXT970 is used by many boards                               */

#ifdef CONFIG_FEC_LXT970

#define MII_LXT970_MIRROR    16  /* Mirror register           */
#define MII_LXT970_IER       17  /* Interrupt Enable Register */
#define MII_LXT970_ISR       18  /* Interrupt Status Register */
#define MII_LXT970_CONFIG    19  /* Configuration Register    */
#define MII_LXT970_CSR       20  /* Chip Status Register      */

static void mii_parse_lxt970_csr(uint mii_reg, struct net_device *dev)
{
        struct fec_enet_private *fep = dev->priv;
        volatile uint *s = &(fep->phy_status);

        *s &= ~(PHY_STAT_SPMASK);

        if (mii_reg & 0x0800) {
                if (mii_reg & 0x1000)
                        *s |= PHY_STAT_100FDX;
                else
                        *s |= PHY_STAT_100HDX;
        }
        else {
                if (mii_reg & 0x1000)
                        *s |= PHY_STAT_10FDX;
                else
                        *s |= PHY_STAT_10HDX;
        }
}

static phy_info_t phy_info_lxt970 = {
        0x07810000,
        "LXT970",

        (const phy_cmd_t []) {  /* config */
#if 0
//              { mk_mii_write(MII_REG_ANAR, 0x0021), NULL },

                /* Set default operation of 100-TX....for some reason
                 * some of these bits are set on power up, which is wrong.
                 */
                { mk_mii_write(MII_LXT970_CONFIG, 0), NULL },
#endif
                { mk_mii_read(MII_REG_CR), mii_parse_cr },
                { mk_mii_read(MII_REG_ANAR), mii_parse_anar },
                { mk_mii_end, }
        },
        (const phy_cmd_t []) {  /* startup - enable interrupts */
                { mk_mii_write(MII_LXT970_IER, 0x0002), NULL },
                { mk_mii_write(MII_REG_CR, 0x1200), NULL }, /* autonegotiate */
                { mk_mii_end, }
        },
        (const phy_cmd_t []) { /* ack_int */
                /* read SR and ISR to acknowledge */

                { mk_mii_read(MII_REG_SR), mii_parse_sr },
                { mk_mii_read(MII_LXT970_ISR), NULL },

                /* find out the current status */

                { mk_mii_read(MII_LXT970_CSR), mii_parse_lxt970_csr },
                { mk_mii_end, }
        },
        (const phy_cmd_t []) {  /* shutdown - disable interrupts */
                { mk_mii_write(MII_LXT970_IER, 0x0000), NULL },
                { mk_mii_end, }
        },
};

#endif /* CONFIG_FEC_LXT970 */

/* ------------------------------------------------------------------------- */
/* The Level one LXT971 is used on some of my custom boards                  */

#ifdef CONFIG_FEC_LXT971

/* register definitions for the 971 */

#define MII_LXT971_PCR       16  /* Port Control Register     */
#define MII_LXT971_SR2       17  /* Status Register 2         */
#define MII_LXT971_IER       18  /* Interrupt Enable Register */
#define MII_LXT971_ISR       19  /* Interrupt Status Register */
#define MII_LXT971_LCR       20  /* LED Control Register      */
#define MII_LXT971_TCR       30  /* Transmit Control Register */

/*
 * I had some nice ideas of running the MDIO faster...
 * The 971 should support 8MHz and I tried it, but things acted really
 * weird, so 2.5 MHz ought to be enough for anyone...
 */

static void mii_parse_lxt971_sr2(uint mii_reg, struct net_device *dev)
{
        struct fec_enet_private *fep = dev->priv;
        volatile uint *s = &(fep->phy_status);

        *s &= ~(PHY_STAT_SPMASK);

        if (mii_reg & 0x4000) {
                if (mii_reg & 0x0200)
                        *s |= PHY_STAT_100FDX;
                else
                        *s |= PHY_STAT_100HDX;
        }
        else {
                if (mii_reg & 0x0200)
                        *s |= PHY_STAT_10FDX;
                else
                        *s |= PHY_STAT_10HDX;
        }
        if (mii_reg & 0x0008)
                *s |= PHY_STAT_FAULT;
}

static phy_info_t phy_info_lxt971 = {
        0x0001378e,
        "LXT971",

        (const phy_cmd_t []) {  /* config */
//              { mk_mii_write(MII_REG_ANAR, 0x021), NULL }, /* 10  Mbps, HD */
                { mk_mii_read(MII_REG_CR), mii_parse_cr },
                { mk_mii_read(MII_REG_ANAR), mii_parse_anar },
                { mk_mii_end, }
        },
        (const phy_cmd_t []) {  /* startup - enable interrupts */
                { mk_mii_write(MII_LXT971_IER, 0x00f2), NULL },
                { mk_mii_write(MII_REG_CR, 0x1200), NULL }, /* autonegotiate */

                /* Somehow does the 971 tell me that the link is down
                 * the first read after power-up.
                 * read here to get a valid value in ack_int */

                { mk_mii_read(MII_REG_SR), mii_parse_sr },
                { mk_mii_end, }
        },
        (const phy_cmd_t []) { /* ack_int */
                /* find out the current status */

                { mk_mii_read(MII_REG_SR), mii_parse_sr },
                { mk_mii_read(MII_LXT971_SR2), mii_parse_lxt971_sr2 },

                /* we only need to read ISR to acknowledge */

                { mk_mii_read(MII_LXT971_ISR), NULL },
                { mk_mii_end, }
        },
        (const phy_cmd_t []) {  /* shutdown - disable interrupts */
                { mk_mii_write(MII_LXT971_IER, 0x0000), NULL },
                { mk_mii_end, }
        },
};

#endif /* CONFIG_FEC_LXT970 */


/* ------------------------------------------------------------------------- */
/* The Quality Semiconductor QS6612 is used on the RPX CLLF                  */

#ifdef CONFIG_FEC_QS6612

/* register definitions */

#define MII_QS6612_MCR       17  /* Mode Control Register      */
#define MII_QS6612_FTR       27  /* Factory Test Register      */
#define MII_QS6612_MCO       28  /* Misc. Control Register     */
#define MII_QS6612_ISR       29  /* Interrupt Source Register  */
#define MII_QS6612_IMR       30  /* Interrupt Mask Register    */
#define MII_QS6612_PCR       31  /* 100BaseTx PHY Control Reg. */

static void mii_parse_qs6612_pcr(uint mii_reg, struct net_device *dev)
{
        struct fec_enet_private *fep = dev->priv;
        volatile uint *s = &(fep->phy_status);

        *s &= ~(PHY_STAT_SPMASK);

        switch((mii_reg >> 2) & 7) {
        case 1: *s |= PHY_STAT_10HDX; break;
        case 2: *s |= PHY_STAT_100HDX; break;
        case 5: *s |= PHY_STAT_10FDX; break;
        case 6: *s |= PHY_STAT_100FDX; break;
        }
}

static phy_info_t phy_info_qs6612 = {
        0x00181440,
        "QS6612",

        (const phy_cmd_t []) {  /* config */
//      { mk_mii_write(MII_REG_ANAR, 0x061), NULL }, /* 10  Mbps */

                /* The PHY powers up isolated on the RPX,
                 * so send a command to allow operation.
                 */

                { mk_mii_write(MII_QS6612_PCR, 0x0dc0), NULL },

                /* parse cr and anar to get some info */

                { mk_mii_read(MII_REG_CR), mii_parse_cr },
                { mk_mii_read(MII_REG_ANAR), mii_parse_anar },
                { mk_mii_end, }
        },
        (const phy_cmd_t []) {  /* startup - enable interrupts */
                { mk_mii_write(MII_QS6612_IMR, 0x003a), NULL },
                { mk_mii_write(MII_REG_CR, 0x1200), NULL }, /* autonegotiate */
                { mk_mii_end, }
        },
        (const phy_cmd_t []) { /* ack_int */

                /* we need to read ISR, SR and ANER to acknowledge */

                { mk_mii_read(MII_QS6612_ISR), NULL },
                { mk_mii_read(MII_REG_SR), mii_parse_sr },
                { mk_mii_read(MII_REG_ANER), NULL },

                /* read pcr to get info */

                { mk_mii_read(MII_QS6612_PCR), mii_parse_qs6612_pcr },
                { mk_mii_end, }
        },
        (const phy_cmd_t []) {  /* shutdown - disable interrupts */
                { mk_mii_write(MII_QS6612_IMR, 0x0000), NULL },
                { mk_mii_end, }
        },
};

#endif /* CONFIG_FEC_QS6612 */

/* ------------------------------------------------------------------------- */
/* The Advanced Micro Devices AM79C874 is used on the ICU862                 */

#ifdef CONFIG_FEC_AM79C874

/* register definitions for the 79C874 */

#define MII_AM79C874_MFR        16  /* Miscellaneous Features Register      */
#define MII_AM79C874_ICSR       17  /* Interrupt Control/Status Register    */
#define MII_AM79C874_DR         18  /* Diagnostic Register                  */
#define MII_AM79C874_PMLR       19  /* Power Management & Loopback Register */
#define MII_AM79C874_MCR        21  /* Mode Control Register                */
#define MII_AM79C874_DC         23  /* Disconnect Counter                   */
#define MII_AM79C874_REC        24  /* Receiver Error Counter               */

static void mii_parse_amd79c874_dr(uint mii_reg, struct net_device *dev, uint data)
{
        volatile struct fec_enet_private *fep = dev->priv;
        uint s = fep->phy_status;

        s &= ~(PHY_STAT_SPMASK);

        /* Register 18: Bit 10 is data rate, 11 is Duplex */
        switch ((mii_reg >> 10) & 3) {
        case 0: s |= PHY_STAT_10HDX;    break;
        case 1: s |= PHY_STAT_100HDX;   break;
        case 2: s |= PHY_STAT_10FDX;    break;
        case 3: s |= PHY_STAT_100FDX;   break;
        }

        fep->phy_status = s;
}

static phy_info_t phy_info_amd79c874 = {
        0x00022561,
        "AM79C874",

        (const phy_cmd_t []) {  /* config */
//              { mk_mii_write(MII_REG_ANAR, 0x021), NULL }, /* 10  Mbps, HD */
                { mk_mii_read(MII_REG_CR), mii_parse_cr },
                { mk_mii_read(MII_REG_ANAR), mii_parse_anar },
                { mk_mii_end, }
        },
        (const phy_cmd_t []) {  /* startup - enable interrupts */
                { mk_mii_write(MII_AM79C874_ICSR, 0xff00), NULL },
                { mk_mii_write(MII_REG_CR, 0x1200), NULL }, /* autonegotiate */
                { mk_mii_end, }
        },
        (const phy_cmd_t []) { /* ack_int */
                /* find out the current status */

                { mk_mii_read(MII_REG_SR), mii_parse_sr },
                { mk_mii_read(MII_AM79C874_DR), mii_parse_amd79c874_dr },

                /* we only need to read ICSR to acknowledge */

                { mk_mii_read(MII_AM79C874_ICSR), NULL },
                { mk_mii_end, }
        },
        (const phy_cmd_t []) {  /* shutdown - disable interrupts */
                { mk_mii_write(MII_AM79C874_ICSR, 0x0000), NULL },
                { mk_mii_end, }
        },
};

#endif /* CONFIG_FEC_AM79C874 */

static phy_info_t *phy_info[] = {

#ifdef CONFIG_FEC_LXT970
        &phy_info_lxt970,
#endif /* CONFIG_FEC_LXT970 */

#ifdef CONFIG_FEC_LXT971
        &phy_info_lxt971,
#endif /* CONFIG_FEC_LXT971 */

#ifdef CONFIG_FEC_QS6612
        &phy_info_qs6612,
#endif /* CONFIG_FEC_QS6612 */

#ifdef CONFIG_FEC_AM79C874
        &phy_info_amd79c874,
#endif /* CONFIG_FEC_AM79C874 */

        NULL
};

static void mii_display_status(struct net_device *dev)
{
        struct fec_enet_private *fep = dev->priv;
        volatile uint *s = &(fep->phy_status);

        if (!fep->link && !fep->old_link) {
                /* Link is still down - don't print anything */
                return;
        }

        printk("%s: status: ", dev->name);

        if (!fep->link) {
                printk("link down");
        } else {
                printk("link up");

                switch(*s & PHY_STAT_SPMASK) {
                case PHY_STAT_100FDX: printk(", 100 Mbps Full Duplex"); break;
                case PHY_STAT_100HDX: printk(", 100 Mbps Half Duplex"); break;
                case PHY_STAT_10FDX: printk(", 10 Mbps Full Duplex"); break;
                case PHY_STAT_10HDX: printk(", 10 Mbps Half Duplex"); break;
                default:
                        printk(", Unknown speed/duplex");
                }

                if (*s & PHY_STAT_ANC)
                        printk(", auto-negotiation complete");
        }

        if (*s & PHY_STAT_FAULT)
                printk(", remote fault");

        printk(".\n");
}

static void mii_display_config(struct work_struct *work)
{
        struct fec_enet_private *fep =
                container_of(work, struct fec_enet_private, phy_task);
        struct net_device *dev = fep->dev;
        volatile uint *s = &(fep->phy_status);

        printk("%s: config: auto-negotiation ", dev->name);

        if (*s & PHY_CONF_ANE)
                printk("on");
        else
                printk("off");

        if (*s & PHY_CONF_100FDX)
                printk(", 100FDX");
        if (*s & PHY_CONF_100HDX)
                printk(", 100HDX");
        if (*s & PHY_CONF_10FDX)
                printk(", 10FDX");
        if (*s & PHY_CONF_10HDX)
                printk(", 10HDX");
        if (!(*s & PHY_CONF_SPMASK))
                printk(", No speed/duplex selected?");

        if (*s & PHY_CONF_LOOP)
                printk(", loopback enabled");

        printk(".\n");

        fep->sequence_done = 1;
}

static void mii_relink(struct work_struct *work)
{
        struct fec_enet_private *fep =
                container_of(work, struct fec_enet_private, phy_task);
        struct net_device *dev = fep->dev;
        int duplex;

        fep->link = (fep->phy_status & PHY_STAT_LINK) ? 1 : 0;
        mii_display_status(dev);
        fep->old_link = fep->link;

        if (fep->link) {
                duplex = 0;
                if (fep->phy_status
                    & (PHY_STAT_100FDX | PHY_STAT_10FDX))
                        duplex = 1;
                fec_restart(dev, duplex);
        }
        else
                fec_stop(dev);

#if 0
        enable_irq(fep->mii_irq);
#endif

}

static void mii_queue_relink(uint mii_reg, struct net_device *dev)
{
        struct fec_enet_private *fep = dev->priv;

        fep->dev = dev;
        INIT_WORK(&fep->phy_task, mii_relink);
        schedule_work(&fep->phy_task);
}

static void mii_queue_config(uint mii_reg, struct net_device *dev)
{
        struct fec_enet_private *fep = dev->priv;

        fep->dev = dev;
        INIT_WORK(&fep->phy_task, mii_display_config);
        schedule_work(&fep->phy_task);
}



phy_cmd_t phy_cmd_relink[] = { { mk_mii_read(MII_REG_CR), mii_queue_relink },
                               { mk_mii_end, } };
phy_cmd_t phy_cmd_config[] = { { mk_mii_read(MII_REG_CR), mii_queue_config },
                               { mk_mii_end, } };



/* Read remainder of PHY ID.
*/
static void
mii_discover_phy3(uint mii_reg, struct net_device *dev)
{
        struct fec_enet_private *fep;
        int     i;

        fep = dev->priv;
        fep->phy_id |= (mii_reg & 0xffff);

        for(i = 0; phy_info[i]; i++)
                if(phy_info[i]->id == (fep->phy_id >> 4))
                        break;

        if(!phy_info[i])
                panic("%s: PHY id 0x%08x is not supported!\n",
                      dev->name, fep->phy_id);

        fep->phy = phy_info[i];
        fep->phy_id_done = 1;

        printk("%s: Phy @ 0x%x, type %s (0x%08x)\n",
                dev->name, fep->phy_addr, fep->phy->name, fep->phy_id);
}

/* Scan all of the MII PHY addresses looking for someone to respond
 * with a valid ID.  This usually happens quickly.
 */
static void
mii_discover_phy(uint mii_reg, struct net_device *dev)
{
        struct fec_enet_private *fep;
        uint    phytype;

        fep = dev->priv;

        if ((phytype = (mii_reg & 0xffff)) != 0xffff) {

                /* Got first part of ID, now get remainder.
                */
                fep->phy_id = phytype << 16;
                mii_queue(dev, mk_mii_read(MII_REG_PHYIR2), mii_discover_phy3);
        } else {
                fep->phy_addr++;
                if (fep->phy_addr < 32) {
                        mii_queue(dev, mk_mii_read(MII_REG_PHYIR1),
                                                        mii_discover_phy);
                } else {
                        printk("fec: No PHY device found.\n");
                }
        }
}
#endif  /* CONFIG_USE_MDIO */

/* This interrupt occurs when the PHY detects a link change.
*/
static
#ifdef CONFIG_RPXCLASSIC
void mii_link_interrupt(void *dev_id)
#else
irqreturn_t mii_link_interrupt(int irq, void * dev_id)
#endif
{
#ifdef  CONFIG_USE_MDIO
        struct  net_device *dev = dev_id;
        struct fec_enet_private *fep = dev->priv;
        volatile immap_t *immap = (immap_t *)IMAP_ADDR;
        volatile fec_t *fecp = &(immap->im_cpm.cp_fec);
        unsigned int ecntrl = fecp->fec_ecntrl;

        /* We need the FEC enabled to access the MII
        */
        if ((ecntrl & FEC_ECNTRL_ETHER_EN) == 0) {
                fecp->fec_ecntrl |= FEC_ECNTRL_ETHER_EN;
        }
#endif  /* CONFIG_USE_MDIO */

#if 0
        disable_irq(fep->mii_irq);  /* disable now, enable later */
#endif


#ifdef  CONFIG_USE_MDIO
        mii_do_cmd(dev, fep->phy->ack_int);
        mii_do_cmd(dev, phy_cmd_relink);  /* restart and display status */

        if ((ecntrl & FEC_ECNTRL_ETHER_EN) == 0) {
                fecp->fec_ecntrl = ecntrl;      /* restore old settings */
        }
#else
printk("%s[%d] %s: unexpected Link interrupt\n", __FILE__,__LINE__,__FUNCTION__);
#endif  /* CONFIG_USE_MDIO */

#ifndef CONFIG_RPXCLASSIC
        return IRQ_RETVAL(IRQ_HANDLED);
#endif  /* CONFIG_RPXCLASSIC */
}

static int
fec_enet_open(struct net_device *dev)
{
        struct fec_enet_private *fep = dev->priv;

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

#ifdef  CONFIG_USE_MDIO
        fep->sequence_done = 0;
        fep->link = 0;

        if (fep->phy) {
                mii_do_cmd(dev, fep->phy->ack_int);
                mii_do_cmd(dev, fep->phy->config);
                mii_do_cmd(dev, phy_cmd_config);  /* display configuration */
                while(!fep->sequence_done)
                        schedule();

                mii_do_cmd(dev, fep->phy->startup);
                netif_start_queue(dev);
                return 0;               /* Success */
        }
        return -ENODEV;         /* No PHY we understand */
#else
        fep->link = 1;
        netif_start_queue(dev);
        return 0;       /* Success */
#endif  /* CONFIG_USE_MDIO */

}

static int
fec_enet_close(struct net_device *dev)
{
        /* Don't know what to do yet.
        */
        netif_stop_queue(dev);
        fec_stop(dev);

        return 0;
}

static struct net_device_stats *fec_enet_get_stats(struct net_device *dev)
{
        struct fec_enet_private *fep = (struct fec_enet_private *)dev->priv;

        return &fep->stats;
}

/* 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?).
 */

static void set_multicast_list(struct net_device *dev)
{
        struct  fec_enet_private *fep;
        volatile fec_t *ep;

        fep = (struct fec_enet_private *)dev->priv;
        ep = &(((immap_t *)IMAP_ADDR)->im_cpm.cp_fec);

        if (dev->flags&IFF_PROMISC) {

                /* Log any net taps. */
                printk("%s: Promiscuous mode enabled.\n", dev->name);
                ep->fec_r_cntrl |= FEC_RCNTRL_PROM;
        } else {

                ep->fec_r_cntrl &= ~FEC_RCNTRL_PROM;

                if (dev->flags & IFF_ALLMULTI) {
                        /* Catch all multicast addresses, so set the
                         * filter to all 1's.
                         */
                        ep->fec_hash_table_high = 0xffffffff;
                        ep->fec_hash_table_low = 0xffffffff;
                }
#if 0
                else {
                        /* Clear filter and add the addresses in the list.
                        */
                        ep->sen_gaddr1 = 0;
                        ep->sen_gaddr2 = 0;
                        ep->sen_gaddr3 = 0;
                        ep->sen_gaddr4 = 0;

                        dmi = dev->mc_list;

                        for (i=0; i<dev->mc_count; i++) {

                                /* Only support group multicast for now.
                                */
                                if (!(dmi->dmi_addr[0] & 1))
                                        continue;

                                /* The address in dmi_addr is LSB first,
                                 * and taddr is MSB first.  We have to
                                 * copy bytes MSB first from dmi_addr.
                                 */
                                mcptr = (u_char *)dmi->dmi_addr + 5;
                                tdptr = (u_char *)&ep->sen_taddrh;
                                for (j=0; j<6; j++)
                                        *tdptr++ = *mcptr--;

                                /* Ask CPM to run CRC and set bit in
                                 * filter mask.
                                 */
                                cpmp->cp_cpcr = mk_cr_cmd(CPM_CR_CH_SCC1, CPM_CR_SET_GADDR) | CPM_CR_FLG;
                                /* this delay is necessary here -- Cort */
                                udelay(10);
                                while (cpmp->cp_cpcr & CPM_CR_FLG);
                        }
                }
#endif
        }
}

/* Initialize the FEC Ethernet on 860T.
 */
static int __init fec_enet_init(void)
{
        struct net_device *dev;
        struct fec_enet_private *fep;
        int i, j, k, err;
        unsigned char   *eap, *iap, *ba;
        dma_addr_t      mem_addr;
        volatile        cbd_t   *bdp;
        cbd_t           *cbd_base;
        volatile        immap_t *immap;
        volatile        fec_t   *fecp;
        bd_t            *bd;
#ifdef CONFIG_SCC_ENET
        unsigned char   tmpaddr[6];
#endif

        immap = (immap_t *)IMAP_ADDR;   /* pointer to internal registers */

        bd = (bd_t *)__res;

        dev = alloc_etherdev(sizeof(*fep));
        if (!dev)
                return -ENOMEM;

        fep = dev->priv;

        fecp = &(immap->im_cpm.cp_fec);

        /* Whack a reset.  We should wait for this.
        */
        fecp->fec_ecntrl = FEC_ECNTRL_PINMUX | FEC_ECNTRL_RESET;
        for (i = 0;
             (fecp->fec_ecntrl & FEC_ECNTRL_RESET) && (i < FEC_RESET_DELAY);
             ++i) {
                udelay(1);
        }
        if (i == FEC_RESET_DELAY) {
                printk ("FEC Reset timeout!\n");
        }

        /* Set the Ethernet address.  If using multiple Enets on the 8xx,
         * this needs some work to get unique addresses.
         */
        eap = (unsigned char *)my_enet_addr;
        iap = bd->bi_enetaddr;

#ifdef CONFIG_SCC_ENET
        /*
         * If a board has Ethernet configured both on a SCC and the
         * FEC, it needs (at least) 2 MAC addresses (we know that Sun
         * disagrees, but anyway). For the FEC port, we create
         * another address by setting one of the address bits above
         * something that would have (up to now) been allocated.
         */
        for (i=0; i<6; i++)
                tmpaddr[i] = *iap++;
        tmpaddr[3] |= 0x80;
        iap = tmpaddr;
#endif

        for (i=0; i<6; i++) {
                dev->dev_addr[i] = *eap++ = *iap++;
        }

        /* Allocate memory for buffer descriptors.
        */
        if (((RX_RING_SIZE + TX_RING_SIZE) * sizeof(cbd_t)) > PAGE_SIZE) {
                printk("FEC init error.  Need more space.\n");
                printk("FEC initialization failed.\n");
                return 1;
        }
        cbd_base = (cbd_t *)dma_alloc_coherent(dev->class_dev.dev, PAGE_SIZE,
                                               &mem_addr, GFP_KERNEL);

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

        fep->skb_cur = fep->skb_dirty = 0;

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

                /* Allocate a page.
                */
                ba = (unsigned char *)dma_alloc_coherent(dev->class_dev.dev,
                                                         PAGE_SIZE,
                                                         &mem_addr,
                                                         GFP_KERNEL);
                /* BUG: no check for failure */

                /* Initialize the BD for every fragment in the page.
                */
                for (j=0; j<FEC_ENET_RX_FRPPG; j++) {
                        bdp->cbd_sc = BD_ENET_RX_EMPTY;
                        bdp->cbd_bufaddr = mem_addr;
                        fep->rx_vaddr[k++] = ba;
                        mem_addr += FEC_ENET_RX_FRSIZE;
                        ba += FEC_ENET_RX_FRSIZE;
                        bdp++;
                }
        }

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

#ifdef CONFIG_FEC_PACKETHOOK
        fep->ph_lock = 0;
        fep->ph_rxhandler = fep->ph_txhandler = NULL;
        fep->ph_proto = 0;
        fep->ph_regaddr = NULL;
        fep->ph_priv = NULL;
#endif

        /* Install our interrupt handler.
        */
        if (request_irq(FEC_INTERRUPT, fec_enet_interrupt, 0, "fec", dev) != 0)
                panic("Could not allocate FEC IRQ!");

#ifdef CONFIG_RPXCLASSIC
        /* Make Port C, bit 15 an input that causes interrupts.
        */
        immap->im_ioport.iop_pcpar &= ~0x0001;
        immap->im_ioport.iop_pcdir &= ~0x0001;
        immap->im_ioport.iop_pcso  &= ~0x0001;
        immap->im_ioport.iop_pcint |=  0x0001;
        cpm_install_handler(CPMVEC_PIO_PC15, mii_link_interrupt, dev);

        /* Make LEDS reflect Link status.
        */
        *((uint *) RPX_CSR_ADDR) &= ~BCSR2_FETHLEDMODE;
#endif

#ifdef PHY_INTERRUPT
        ((immap_t *)IMAP_ADDR)->im_siu_conf.sc_siel |=
                (0x80000000 >> PHY_INTERRUPT);

        if (request_irq(PHY_INTERRUPT, mii_link_interrupt, 0, "mii", dev) != 0)
                panic("Could not allocate MII IRQ!");
#endif

        dev->base_addr = (unsigned long)fecp;

        /* The FEC Ethernet specific entries in the device structure. */
        dev->open = fec_enet_open;
        dev->hard_start_xmit = fec_enet_start_xmit;
        dev->tx_timeout = fec_timeout;
        dev->watchdog_timeo = TX_TIMEOUT;
        dev->stop = fec_enet_close;
        dev->get_stats = fec_enet_get_stats;
        dev->set_multicast_list = set_multicast_list;

#ifdef  CONFIG_USE_MDIO
        for (i=0; i<NMII-1; i++)
                mii_cmds[i].mii_next = &mii_cmds[i+1];
        mii_free = mii_cmds;
#endif  /* CONFIG_USE_MDIO */

        /* Configure all of port D for MII.
        */
        immap->im_ioport.iop_pdpar = 0x1fff;

        /* Bits moved from Rev. D onward.
        */
        if ((mfspr(SPRN_IMMR) & 0xffff) < 0x0501)
                immap->im_ioport.iop_pddir = 0x1c58;    /* Pre rev. D */
        else
                immap->im_ioport.iop_pddir = 0x1fff;    /* Rev. D and later */

#ifdef  CONFIG_USE_MDIO
        /* Set MII speed to 2.5 MHz
        */
        fecp->fec_mii_speed = fep->phy_speed =
                (( (bd->bi_intfreq + 500000) / 2500000 / 2 ) & 0x3F ) << 1;
#else
        fecp->fec_mii_speed = 0;        /* turn off MDIO */
#endif  /* CONFIG_USE_MDIO */

        err = register_netdev(dev);
        if (err) {
                free_netdev(dev);
                return err;
        }

        printk ("%s: FEC ENET Version 0.2, FEC irq %d"
#ifdef PHY_INTERRUPT
                ", MII irq %d"
#endif
                ", addr ",
                dev->name, FEC_INTERRUPT
#ifdef PHY_INTERRUPT
                , PHY_INTERRUPT
#endif
        );
        for (i=0; i<6; i++)
                printk("%02x%c", dev->dev_addr[i], (i==5) ? '\n' : ':');

#ifdef  CONFIG_USE_MDIO /* start in full duplex mode, and negotiate speed */
        fec_restart (dev, 1);
#else                   /* always use half duplex mode only */
        fec_restart (dev, 0);
#endif

#ifdef  CONFIG_USE_MDIO
        /* Queue up command to detect the PHY and initialize the
         * remainder of the interface.
         */
        fep->phy_id_done = 0;
        fep->phy_addr = 0;
        mii_queue(dev, mk_mii_read(MII_REG_PHYIR1), mii_discover_phy);
#endif  /* CONFIG_USE_MDIO */

        return 0;
}
module_init(fec_enet_init);

/* 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;
        int i;
        volatile        cbd_t   *bdp;
        volatile        immap_t *immap;
        volatile        fec_t   *fecp;

        immap = (immap_t *)IMAP_ADDR;   /* pointer to internal registers */

        fecp = &(immap->im_cpm.cp_fec);

        fep = dev->priv;

        /* Whack a reset.  We should wait for this.
        */
        fecp->fec_ecntrl = FEC_ECNTRL_PINMUX | FEC_ECNTRL_RESET;
        for (i = 0;
             (fecp->fec_ecntrl & FEC_ECNTRL_RESET) && (i < FEC_RESET_DELAY);
             ++i) {
                udelay(1);
        }
        if (i == FEC_RESET_DELAY) {
                printk ("FEC Reset timeout!\n");
        }

        /* Set station address.
        */
        fecp->fec_addr_low  = (my_enet_addr[0] << 16) | my_enet_addr[1];
        fecp->fec_addr_high =  my_enet_addr[2];

        /* Reset all multicast.
        */
        fecp->fec_hash_table_high = 0;
        fecp->fec_hash_table_low  = 0;

        /* Set maximum receive buffer size.
        */
        fecp->fec_r_buff_size = PKT_MAXBLR_SIZE;
        fecp->fec_r_hash = PKT_MAXBUF_SIZE;

        /* Set receive and transmit descriptor base.
        */
        fecp->fec_r_des_start = iopa((uint)(fep->rx_bd_base));
        fecp->fec_x_des_start = iopa((uint)(fep->tx_bd_base));

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

        /* 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 = BD_ENET_RX_EMPTY;
                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;

        /* Enable MII mode.
        */
        if (duplex) {
                fecp->fec_r_cntrl = FEC_RCNTRL_MII_MODE;        /* MII enable */
                fecp->fec_x_cntrl = FEC_TCNTRL_FDEN;            /* FD enable */
        }
        else {
                fecp->fec_r_cntrl = FEC_RCNTRL_MII_MODE | FEC_RCNTRL_DRT;
                fecp->fec_x_cntrl = 0;
        }
        fep->full_duplex = duplex;

        /* Enable big endian and don't care about SDMA FC.
        */
        fecp->fec_fun_code = 0x78000000;

#ifdef  CONFIG_USE_MDIO
        /* Set MII speed.
        */
        fecp->fec_mii_speed = fep->phy_speed;
#endif  /* CONFIG_USE_MDIO */

        /* Clear any outstanding interrupt.
        */
        fecp->fec_ievent = 0xffc0;

        fecp->fec_ivec = (FEC_INTERRUPT/2) << 29;

        /* Enable interrupts we wish to service.
        */
        fecp->fec_imask = ( FEC_ENET_TXF | FEC_ENET_TXB |
                            FEC_ENET_RXF | FEC_ENET_RXB | FEC_ENET_MII );

        /* And last, enable the transmit and receive processing.
        */
        fecp->fec_ecntrl = FEC_ECNTRL_PINMUX | FEC_ECNTRL_ETHER_EN;
        fecp->fec_r_des_active = 0x01000000;
}

static void
fec_stop(struct net_device *dev)
{
        volatile        immap_t *immap;
        volatile        fec_t   *fecp;
        struct fec_enet_private *fep;
        int i;

        immap = (immap_t *)IMAP_ADDR;   /* pointer to internal registers */

        fecp = &(immap->im_cpm.cp_fec);

        if ((fecp->fec_ecntrl & FEC_ECNTRL_ETHER_EN) == 0)
                return; /* already down */

        fep = dev->priv;


        fecp->fec_x_cntrl = 0x01;       /* Graceful transmit stop */

        for (i = 0;
             ((fecp->fec_ievent & 0x10000000) == 0) && (i < FEC_RESET_DELAY);
             ++i) {
                udelay(1);
        }
        if (i == FEC_RESET_DELAY) {
                printk ("FEC timeout on graceful transmit stop\n");
        }

        /* Clear outstanding MII command interrupts.
        */
        fecp->fec_ievent = FEC_ENET_MII;

        /* Enable MII command finished interrupt
        */
        fecp->fec_ivec = (FEC_INTERRUPT/2) << 29;
        fecp->fec_imask = FEC_ENET_MII;

#ifdef  CONFIG_USE_MDIO
        /* Set MII speed.
        */
        fecp->fec_mii_speed = fep->phy_speed;
#endif  /* CONFIG_USE_MDIO */

        /* Disable FEC
        */
        fecp->fec_ecntrl &= ~(FEC_ECNTRL_ETHER_EN);
}