patch-2_6_7-vs1_9_1_12

[linux-2.6.git] / arch / ppc / 8260_io / fcc_enet.c

/*
 * Fast Ethernet Controller (FCC) driver for Motorola MPC8260.
 * Copyright (c) 2000 MontaVista Software, Inc.   Dan Malek (dmalek@jlc.net)
 *
 * This version of the driver is a combination of the 8xx fec and
 * 8260 SCC Ethernet drivers.  This version has some additional
 * configuration options, which should probably be moved out of
 * here.  This driver currently works for the EST SBC8260,
 * SBS Diablo/BCM, Embedded Planet RPX6, TQM8260, and others.
 *
 * Right now, I am very watseful 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.  Since this is a cache coherent processor and CPM,
 * I could also preallocate SKB's and use them directly on the interface.
 *
 */

#include <linux/config.h>
#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 <asm/immap_8260.h>
#include <asm/pgtable.h>
#include <asm/mpc8260.h>
#include <asm/irq.h>
#include <asm/bitops.h>
#include <asm/uaccess.h>
#include <asm/cpm_8260.h>

/* The transmitter timeout
 */
#define TX_TIMEOUT      (2*HZ)

#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;

/* 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 */

/* 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.
 */
#define FCC_ENET_RX_PAGES       16
#define FCC_ENET_RX_FRSIZE      2048
#define FCC_ENET_RX_FRPPG       (PAGE_SIZE / FCC_ENET_RX_FRSIZE)
#define RX_RING_SIZE            (FCC_ENET_RX_FRPPG * FCC_ENET_RX_PAGES)
#define TX_RING_SIZE            16      /* Must be power of two */
#define TX_RING_MOD_MASK        15      /*   for this to work */

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

/* Maximum input DMA size.  Must be a should(?) be a multiple of 4.
*/
#define PKT_MAXDMA_SIZE         1520

/* Maximum input buffer size.  Must be a multiple of 32.
*/
#define PKT_MAXBLR_SIZE         1536

static int fcc_enet_open(struct net_device *dev);
static int fcc_enet_start_xmit(struct sk_buff *skb, struct net_device *dev);
static int fcc_enet_rx(struct net_device *dev);
static irqreturn_t fcc_enet_interrupt(int irq, void *dev_id, struct pt_regs *);
static int fcc_enet_close(struct net_device *dev);
static struct net_device_stats *fcc_enet_get_stats(struct net_device *dev);
static void set_multicast_list(struct net_device *dev);
static void fcc_restart(struct net_device *dev, int duplex);
static int fcc_enet_set_mac_address(struct net_device *dev, void *addr);

/* These will be configurable for the FCC choice.
 * Multiple ports can be configured.  There is little choice among the
 * I/O pins to the PHY, except the clocks.  We will need some board
 * dependent clock selection.
 * Why in the hell did I put these inside #ifdef's?  I dunno, maybe to
 * help show what pins are used for each device.
 */

/* I/O Pin assignment for FCC1.  I don't yet know the best way to do this,
 * but there is little variation among the choices.
 */
#define PA1_COL         ((uint)0x00000001)
#define PA1_CRS         ((uint)0x00000002)
#define PA1_TXER        ((uint)0x00000004)
#define PA1_TXEN        ((uint)0x00000008)
#define PA1_RXDV        ((uint)0x00000010)
#define PA1_RXER        ((uint)0x00000020)
#define PA1_TXDAT       ((uint)0x00003c00)
#define PA1_RXDAT       ((uint)0x0003c000)
#define PA1_PSORA0      (PA1_RXDAT | PA1_TXDAT)
#define PA1_PSORA1      (PA1_COL | PA1_CRS | PA1_TXER | PA1_TXEN | \
                                PA1_RXDV | PA1_RXER)
#define PA1_DIRA0       (PA1_RXDAT | PA1_CRS | PA1_COL | PA1_RXER | PA1_RXDV)
#define PA1_DIRA1       (PA1_TXDAT | PA1_TXEN | PA1_TXER)

#ifdef CONFIG_SBC82xx
/* rx is clk9, tx is clk10
 */
#define PC_F1RXCLK     ((uint)0x00000100)
#define PC_F1TXCLK     ((uint)0x00000200)
#define CMX1_CLK_ROUTE ((uint)0x25000000)
#define CMX1_CLK_MASK  ((uint)0xff000000)
#else
/* CLK12 is receive, CLK11 is transmit.  These are board specific.
*/
#define PC_F1RXCLK      ((uint)0x00000800)
#define PC_F1TXCLK      ((uint)0x00000400)
#define CMX1_CLK_ROUTE  ((uint)0x3e000000)
#define CMX1_CLK_MASK   ((uint)0xff000000)
#endif /* !CONFIG_SBC82xx */

/* I/O Pin assignment for FCC2.  I don't yet know the best way to do this,
 * but there is little variation among the choices.
 */
#define PB2_TXER        ((uint)0x00000001)
#define PB2_RXDV        ((uint)0x00000002)
#define PB2_TXEN        ((uint)0x00000004)
#define PB2_RXER        ((uint)0x00000008)
#define PB2_COL         ((uint)0x00000010)
#define PB2_CRS         ((uint)0x00000020)
#define PB2_TXDAT       ((uint)0x000003c0)
#define PB2_RXDAT       ((uint)0x00003c00)
#define PB2_PSORB0      (PB2_RXDAT | PB2_TXDAT | PB2_CRS | PB2_COL | \
                                PB2_RXER | PB2_RXDV | PB2_TXER)
#define PB2_PSORB1      (PB2_TXEN)
#define PB2_DIRB0       (PB2_RXDAT | PB2_CRS | PB2_COL | PB2_RXER | PB2_RXDV)
#define PB2_DIRB1       (PB2_TXDAT | PB2_TXEN | PB2_TXER)

/* CLK13 is receive, CLK14 is transmit.  These are board dependent.
*/
#define PC_F2RXCLK      ((uint)0x00001000)
#define PC_F2TXCLK      ((uint)0x00002000)
#define CMX2_CLK_ROUTE  ((uint)0x00250000)
#define CMX2_CLK_MASK   ((uint)0x00ff0000)

/* I/O Pin assignment for FCC3.  I don't yet know the best way to do this,
 * but there is little variation among the choices.
 */
#define PB3_RXDV        ((uint)0x00004000)
#define PB3_RXER        ((uint)0x00008000)
#define PB3_TXER        ((uint)0x00010000)
#define PB3_TXEN        ((uint)0x00020000)
#define PB3_COL         ((uint)0x00040000)
#define PB3_CRS         ((uint)0x00080000)
#define PB3_TXDAT       ((uint)0x0f000000)
#define PB3_RXDAT       ((uint)0x00f00000)
#define PB3_PSORB0      (PB3_RXDAT | PB3_TXDAT | PB3_CRS | PB3_COL | \
                                PB3_RXER | PB3_RXDV | PB3_TXER | PB3_TXEN)
#define PB3_PSORB1      (0)
#define PB3_DIRB0       (PB3_RXDAT | PB3_CRS | PB3_COL | PB3_RXER | PB3_RXDV)
#define PB3_DIRB1       (PB3_TXDAT | PB3_TXEN | PB3_TXER)

/* CLK15 is receive, CLK16 is transmit.  These are board dependent.
*/
#define PC_F3RXCLK      ((uint)0x00004000)
#define PC_F3TXCLK      ((uint)0x00008000)
#define CMX3_CLK_ROUTE  ((uint)0x00003700)
#define CMX3_CLK_MASK   ((uint)0x0000ff00)

/* MII status/control serial interface.
*/
#ifdef  CONFIG_TQM8260
/* TQM8260 has MDIO and MDCK on PC30 and PC31 respectively */
#define PC_MDIO         ((uint)0x00000002)
#define PC_MDCK         ((uint)0x00000001)
#else
#define PC_MDIO         ((uint)0x00000004)
#define PC_MDCK         ((uint)0x00000020)
#endif

/* A table of information for supporting FCCs.  This does two things.
 * First, we know how many FCCs we have and they are always externally
 * numbered from zero.  Second, it holds control register and I/O
 * information that could be different among board designs.
 */
typedef struct fcc_info {
        uint    fc_fccnum;
        uint    fc_cpmblock;
        uint    fc_cpmpage;
        uint    fc_proff;
        uint    fc_interrupt;
        uint    fc_trxclocks;
        uint    fc_clockroute;
        uint    fc_clockmask;
        uint    fc_mdio;
        uint    fc_mdck;
} fcc_info_t;

static fcc_info_t fcc_ports[] = {
#ifdef CONFIG_FCC1_ENET
        { 0, CPM_CR_FCC1_SBLOCK, CPM_CR_FCC1_PAGE, PROFF_FCC1, SIU_INT_FCC1,
                (PC_F1RXCLK | PC_F1TXCLK), CMX1_CLK_ROUTE, CMX1_CLK_MASK,
# if defined(CONFIG_TQM8260)
                PC_MDIO, PC_MDCK },
# else
                0x00000004, 0x00000100 },
# endif
#endif
#ifdef CONFIG_FCC2_ENET
        { 1, CPM_CR_FCC2_SBLOCK, CPM_CR_FCC2_PAGE, PROFF_FCC2, SIU_INT_FCC2,
                (PC_F2RXCLK | PC_F2TXCLK), CMX2_CLK_ROUTE, CMX2_CLK_MASK,
# if defined(CONFIG_TQM8260)
                PC_MDIO, PC_MDCK },
# elif defined(CONFIG_EST8260) || defined(CONFIG_ADS8260)
                0x00400000, 0x00200000 },
# else
                0x00000002, 0x00000080 },
# endif
#endif
#ifdef CONFIG_FCC3_ENET
        { 2, CPM_CR_FCC3_SBLOCK, CPM_CR_FCC3_PAGE, PROFF_FCC3, SIU_INT_FCC3,
                (PC_F3RXCLK | PC_F3TXCLK), CMX3_CLK_ROUTE, CMX3_CLK_MASK,
# if defined(CONFIG_TQM8260)
                PC_MDIO, PC_MDCK },
# else
                0x00000001, 0x00000040 },
# endif
#endif
};

/* The FCC 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 fcc_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;

        atomic_t n_pkts;  /* Number of packets in tx ring */

        /* 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. */
        volatile fcc_t  *fccp;
        volatile fcc_enet_t     *ep;
        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;
        phy_info_t      *phy;
        struct tq_struct phy_task;

        uint    sequence_done;

        uint    phy_addr;
#endif  /* CONFIG_USE_MDIO */

        int     link;
        int     old_link;
        int     full_duplex;

        fcc_info_t      *fip;
};

static void init_fcc_shutdown(fcc_info_t *fip, struct fcc_enet_private *cep,
        volatile immap_t *immap);
static void init_fcc_startup(fcc_info_t *fip, struct net_device *dev);
static void init_fcc_ioports(fcc_info_t *fip, volatile iop8260_t *io,
        volatile immap_t *immap);
static void init_fcc_param(fcc_info_t *fip, struct net_device *dev,
        volatile immap_t *immap);

#ifdef  CONFIG_USE_MDIO
static int      mii_queue(struct net_device *dev, int request, void (*func)(uint, struct net_device *));
static uint     mii_send_receive(fcc_info_t *fip, uint cmd);

static void     fcc_stop(struct net_device *dev);

/* Make MII read/write commands for the FCC.
*/
#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 */


static int
fcc_enet_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
        struct fcc_enet_private *cep = (struct fcc_enet_private *)dev->priv;
        volatile cbd_t  *bdp;
        int idx;

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

        /* Fill in a Tx ring entry */
        bdp = cep->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 cep->tx_full 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;

        /* If the frame is short, tell CPM to pad it. */
        if (skb->len <= ETH_ZLEN)
                bdp->cbd_sc |= BD_ENET_TX_PAD;
        else
                bdp->cbd_sc &= ~BD_ENET_TX_PAD;

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

        spin_lock_irq(&cep->lock);

        /* Save skb pointer. */
        idx = cep->skb_cur & TX_RING_MOD_MASK;
        if (cep->tx_skbuff[idx]) {
                /* This should never happen (any more).
                   Leave the sanity check in for now... */
                printk(KERN_ERR "EEP. cep->tx_skbuff[%d] is %p not NULL in %s\n", 
                       idx, cep->tx_skbuff[idx], __func__);
                printk(KERN_ERR "Expect to lose %d bytes of sock space", 
                       cep->tx_skbuff[idx]->truesize);
        }
        cep->tx_skbuff[idx] = skb;

        cep->stats.tx_bytes += skb->len;
        cep->skb_cur++;

        atomic_inc(&cep->n_pkts);

        /* Send it on its way.  Tell CPM 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);

#if 0
        /* Errata says don't do this. */
        cep->fccp->fcc_ftodr = 0x8000;
#endif
        dev->trans_start = jiffies;

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


        /* If the tx_ring is full, stop the queue */
        if (atomic_read(&cep->n_pkts) >= (TX_RING_SIZE-1)) {
          if (!netif_queue_stopped(dev)) {
                netif_stop_queue(dev);    
                cep->tx_full = 1;
          }
        }

        cep->cur_tx = (cbd_t *)bdp;

        spin_unlock_irq(&cep->lock);

        return 0;
}


static void
fcc_enet_timeout(struct net_device *dev)
{
        struct fcc_enet_private *cep = (struct fcc_enet_private *)dev->priv;

        printk("%s: transmit timed out.\n", dev->name);
        cep->stats.tx_errors++;
#ifndef final_version
        {
                int     i;
                cbd_t   *bdp;
                printk(" Ring data dump: cur_tx %p%s cur_rx %p.\n",
                       cep->cur_tx, cep->tx_full ? " (full)" : "",
                       cep->cur_rx);
                bdp = cep->tx_bd_base;
                printk(" Tx @base %p :\n", bdp);
                for (i = 0 ; i < TX_RING_SIZE; i++, bdp++)
                        printk("%04x %04x %08x\n",
                               bdp->cbd_sc,
                               bdp->cbd_datlen,
                               bdp->cbd_bufaddr);
                bdp = cep->rx_bd_base;
                printk(" Rx @base %p :\n", bdp);
                for (i = 0 ; i < RX_RING_SIZE; i++, bdp++)
                        printk("%04x %04x %08x\n",
                               bdp->cbd_sc,
                               bdp->cbd_datlen,
                               bdp->cbd_bufaddr);
        }
#endif
        if (!cep->tx_full)
                netif_wake_queue(dev);
}

/* The interrupt handler. */
static irqreturn_t
fcc_enet_interrupt(int irq, void * dev_id, struct pt_regs * regs)
{
        struct  net_device *dev = dev_id;
        volatile struct fcc_enet_private *cep;
        volatile cbd_t  *bdp;
        ushort  int_events;
        int     must_restart;
        int idx;

        cep = (struct fcc_enet_private *)dev->priv;

        /* Get the interrupt events that caused us to be here.
        */
        int_events = cep->fccp->fcc_fcce;
        cep->fccp->fcc_fcce = int_events;
        must_restart = 0;

        /* Handle receive event in its own function.
        */
        if (int_events & FCC_ENET_RXF)
                fcc_enet_rx(dev_id);

        /* Check for a transmit error.  The manual is a little unclear
         * about this, so the debug code until I get it figured out.  It
         * appears that if TXE is set, then TXB is not set.  However,
         * if carrier sense is lost during frame transmission, the TXE
         * bit is set, "and continues the buffer transmission normally."
         * I don't know if "normally" implies TXB is set when the buffer
         * descriptor is closed.....trial and error :-).
         */

        /* Transmit OK, or non-fatal error.  Update the buffer descriptors.
        */
        if (int_events & (FCC_ENET_TXE | FCC_ENET_TXB)) {
            spin_lock(&cep->lock);
            bdp = cep->dirty_tx;
            while ((bdp->cbd_sc&BD_ENET_TX_READY)==0) {
                if ((bdp==cep->cur_tx) && (cep->tx_full == 0))
                    break;

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


                /* No heartbeat or Lost carrier are not really bad errors.
                 * The others require a restart transmit command.
                 */
                if (bdp->cbd_sc &
                    (BD_ENET_TX_LC | BD_ENET_TX_RL | BD_ENET_TX_UN)) {
                        must_restart = 1;
                        cep->stats.tx_errors++;
                }

                cep->stats.tx_packets++;

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

                /* Free the sk buffer associated with this last transmit. */
                idx = cep->skb_dirty & TX_RING_MOD_MASK;
                dev_kfree_skb_irq(cep->tx_skbuff[idx]);
                cep->tx_skbuff[idx] = NULL;
                cep->skb_dirty++;

                atomic_dec(&cep->n_pkts);

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

                /* I don't know if we can be held off from processing these
                 * interrupts for more than one frame time.  I really hope
                 * not.  In such a case, we would now want to check the
                 * currently available BD (cur_tx) and determine if any
                 * buffers between the dirty_tx and cur_tx have also been
                 * sent.  We would want to process anything in between that
                 * does not have BD_ENET_TX_READY set.
                 */

                /* Since we have freed up a buffer, the ring is no longer
                 * full.
                 */
                if (cep->tx_full) {
                        cep->tx_full = 0;
                        if (netif_queue_stopped(dev)) {
                                netif_wake_queue(dev);
                        }
                }

                cep->dirty_tx = (cbd_t *)bdp;
            }

            if (must_restart) {
                volatile cpm8260_t *cp;

                /* Some transmit errors cause the transmitter to shut
                 * down.  We now issue a restart transmit.  Since the
                 * errors close the BD and update the pointers, the restart
                 * _should_ pick up without having to reset any of our
                 * pointers either.  Also, To workaround 8260 device erratum
                 * CPM37, we must disable and then re-enable the transmitter
                 * following a Late Collision, Underrun, or Retry Limit error.
                 */
                cep->fccp->fcc_gfmr &= ~FCC_GFMR_ENT;
                udelay(10); /* wait a few microseconds just on principle */
                cep->fccp->fcc_gfmr |=  FCC_GFMR_ENT;

                cp = cpmp;
                cp->cp_cpcr =
                    mk_cr_cmd(cep->fip->fc_cpmpage, cep->fip->fc_cpmblock,
                                0x0c, CPM_CR_RESTART_TX) | CPM_CR_FLG;
                while (cp->cp_cpcr & CPM_CR_FLG);
            }
            spin_unlock(&cep->lock);
        }

        /* Check for receive busy, i.e. packets coming but no place to
         * put them.
         */
        if (int_events & FCC_ENET_BSY) {
                cep->stats.rx_dropped++;
        }
        return IRQ_HANDLED;
}

/* 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 int
fcc_enet_rx(struct net_device *dev)
{
        struct  fcc_enet_private *cep;
        volatile cbd_t  *bdp;
        struct  sk_buff *skb;
        ushort  pkt_len;

        cep = (struct fcc_enet_private *)dev->priv;

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

for (;;) {
        if (bdp->cbd_sc & BD_ENET_RX_EMPTY)
                break;

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

        /* Frame too long or too short. */
        if (bdp->cbd_sc & (BD_ENET_RX_LG | BD_ENET_RX_SH))
                cep->stats.rx_length_errors++;
        if (bdp->cbd_sc & BD_ENET_RX_NO)        /* Frame alignment */
                cep->stats.rx_frame_errors++;
        if (bdp->cbd_sc & BD_ENET_RX_CR)        /* CRC Error */
                cep->stats.rx_crc_errors++;
        if (bdp->cbd_sc & BD_ENET_RX_OV)        /* FIFO overrun */
                cep->stats.rx_crc_errors++;
        if (bdp->cbd_sc & BD_ENET_RX_CL)        /* Late Collision */
                cep->stats.rx_frame_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 | BD_ENET_RX_CL)))
        {
                /* Process the incoming frame. */
                cep->stats.rx_packets++;

                /* Remove the FCS from the packet length. */
                pkt_len = bdp->cbd_datlen - 4;
                cep->stats.rx_bytes += pkt_len;

                /* This does 16 byte alignment, much more than we need. */
                skb = dev_alloc_skb(pkt_len);

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

        /* 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 = cep->rx_bd_base;
        else
                bdp++;

   }
        cep->cur_rx = (cbd_t *)bdp;

        return 0;
}

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

        return 0;
}

static struct net_device_stats *fcc_enet_get_stats(struct net_device *dev)
{
        struct fcc_enet_private *cep = (struct fcc_enet_private *)dev->priv;

        return &cep->stats;
}

#ifdef  CONFIG_USE_MDIO

/* NOTE: Most of the following comes from the FEC driver for 860. The
 * overall structure of MII code has been retained (as it's proved stable
 * and well-tested), but actual transfer requests are processed "at once"
 * instead of being queued (there's no interrupt-driven MII transfer
 * mechanism, one has to toggle the data/clock bits manually).
 */
static int
mii_queue(struct net_device *dev, int regval, void (*func)(uint, struct net_device *))
{
        struct fcc_enet_private *fep;
        int             retval, tmp;

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

        retval = 0;

        tmp = mii_send_receive(fep->fip, regval);
        if (func)
                func(tmp, dev);

        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)
{
        volatile struct fcc_enet_private *fep = dev->priv;
        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->phy_status = s;
        fep->link = (s & PHY_STAT_LINK) ? 1 : 0;
}

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

        fep->phy_status = s;
}

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

        fep->phy_status = s;
}
/* ------------------------------------------------------------------------- */
/* The Level one LXT970 is used by many boards                               */

#ifdef CONFIG_FCC_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)
{
        volatile struct fcc_enet_private *fep = dev->priv;
        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;
        }

        fep->phy_status = s;
}

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_FCC_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)
{
        volatile struct fcc_enet_private *fep = dev->priv;
        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;

        fep->phy_status = s;
}

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_FCC_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)
{
        volatile struct fcc_enet_private *fep = dev->priv;
        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;
        }

        fep->phy_status = s;
}

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 */


static phy_info_t *phy_info[] = {

#ifdef CONFIG_FCC_LXT970
        &phy_info_lxt970,
#endif /* CONFIG_FEC_LXT970 */

#ifdef CONFIG_FCC_LXT971
        &phy_info_lxt971,
#endif /* CONFIG_FEC_LXT971 */

#ifdef CONFIG_FCC_QS6612
        &phy_info_qs6612,
#endif /* CONFIG_FEC_LXT971 */

        NULL
};

static void mii_display_status(struct net_device *dev)
{
        volatile struct fcc_enet_private *fep = dev->priv;
        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 net_device *dev)
{
        volatile struct fcc_enet_private *fep = dev->priv;
        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 net_device *dev)
{
        struct fcc_enet_private *fep = dev->priv;
        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;
                fcc_restart(dev, duplex);
        } else {
                fcc_stop(dev);
        }
}

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

        fep->phy_task.routine = (void *)mii_relink;
        fep->phy_task.data = dev;
        schedule_task(&fep->phy_task);
}

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

        fep->phy_task.routine = (void *)mii_display_config;
        fep->phy_task.data = dev;
        schedule_task(&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 fcc_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];

        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 fcc_enet_private *fep;
        uint    phytype;

        fep = dev->priv;

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

                /* 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");
                }
        }
}

/* This interrupt occurs when the PHY detects a link change. */
static irqreturn_t
mii_link_interrupt(int irq, void * dev_id, struct pt_regs * regs)
{
        struct  net_device *dev = dev_id;
        struct fcc_enet_private *fep = dev->priv;

        mii_do_cmd(dev, fep->phy->ack_int);
        mii_do_cmd(dev, phy_cmd_relink);  /* restart and display status */
        return IRQ_HANDLED;
}

#endif  /* CONFIG_USE_MDIO */

/* 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  fcc_enet_private *cep;
        struct  dev_mc_list *dmi;
        u_char  *mcptr, *tdptr;
        volatile fcc_enet_t *ep;
        int     i, j;

        cep = (struct fcc_enet_private *)dev->priv;

return;
        /* Get pointer to FCC area in parameter RAM.
        */
        ep = (fcc_enet_t *)dev->base_addr;

        if (dev->flags&IFF_PROMISC) {
        
                /* Log any net taps. */
                printk("%s: Promiscuous mode enabled.\n", dev->name);
                cep->fccp->fcc_fpsmr |= FCC_PSMR_PRO;
        } else {

                cep->fccp->fcc_fpsmr &= ~FCC_PSMR_PRO;

                if (dev->flags & IFF_ALLMULTI) {
                        /* Catch all multicast addresses, so set the
                         * filter to all 1's.
                         */
                        ep->fen_gaddrh = 0xffffffff;
                        ep->fen_gaddrl = 0xffffffff;
                }
                else {
                        /* Clear filter and add the addresses in the list.
                        */
                        ep->fen_gaddrh = 0;
                        ep->fen_gaddrl = 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->fen_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(cep->fip->fc_cpmpage,
                                                cep->fip->fc_cpmblock, 0x0c,
                                                CPM_CR_SET_GADDR) | CPM_CR_FLG;
                                udelay(10);
                                while (cpmp->cp_cpcr & CPM_CR_FLG);
                        }
                }
        }
}


/* Set the individual MAC address.
 */
int fcc_enet_set_mac_address(struct net_device *dev, void *p)
{
        struct sockaddr *addr= (struct sockaddr *) p;
        struct fcc_enet_private *cep;
        volatile fcc_enet_t *ep;
        unsigned char *eap;
        int i;

        cep = (struct fcc_enet_private *)(dev->priv);
        ep = cep->ep;

        if (netif_running(dev))
                return -EBUSY;

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

        eap = (unsigned char *) &(ep->fen_paddrh);
        for (i=5; i>=0; i--)
                *eap++ = addr->sa_data[i];

        return 0;
}


/* Initialize the CPM Ethernet on FCC.
 */
static int __init fec_enet_init(void)
{
        struct net_device *dev;
        struct fcc_enet_private *cep;
        fcc_info_t      *fip;
        int     i, np, err;
        volatile        immap_t         *immap;
        volatile        iop8260_t       *io;

        immap = (immap_t *)IMAP_ADDR;   /* and to internal registers */
        io = &immap->im_ioport;

        np = sizeof(fcc_ports) / sizeof(fcc_info_t);
        fip = fcc_ports;

        while (np-- > 0) {
                /* Create an Ethernet device instance.
                */
                dev = alloc_etherdev(sizeof(*cep));
                if (!dev)
                        return -ENOMEM;

                cep = dev->priv;
                spin_lock_init(&cep->lock);
                cep->fip = fip;

                init_fcc_shutdown(fip, cep, immap);
                init_fcc_ioports(fip, io, immap);
                init_fcc_param(fip, dev, immap);

                dev->base_addr = (unsigned long)(cep->ep);

                /* The CPM Ethernet specific entries in the device
                 * structure.
                 */
                dev->open = fcc_enet_open;
                dev->hard_start_xmit = fcc_enet_start_xmit;
                dev->tx_timeout = fcc_enet_timeout;
                dev->watchdog_timeo = TX_TIMEOUT;
                dev->stop = fcc_enet_close;
                dev->get_stats = fcc_enet_get_stats;
                dev->set_multicast_list = set_multicast_list;
                dev->set_mac_address = fcc_enet_set_mac_address;

                init_fcc_startup(fip, dev);

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

                printk("%s: FCC ENET Version 0.3, ", dev->name);
                for (i=0; i<5; i++)
                        printk("%02x:", dev->dev_addr[i]);
                printk("%02x\n", dev->dev_addr[5]);

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

                fip++;
        }

        return 0;
}
module_init(fec_enet_init);

/* Make sure the device is shut down during initialization.
*/
static void __init
init_fcc_shutdown(fcc_info_t *fip, struct fcc_enet_private *cep,
                                                volatile immap_t *immap)
{
        volatile        fcc_enet_t      *ep;
        volatile        fcc_t           *fccp;

        /* Get pointer to FCC area in parameter RAM.
        */
        ep = (fcc_enet_t *)(&immap->im_dprambase[fip->fc_proff]);

        /* And another to the FCC register area.
        */
        fccp = (volatile fcc_t *)(&immap->im_fcc[fip->fc_fccnum]);
        cep->fccp = fccp;               /* Keep the pointers handy */
        cep->ep = ep;

        /* Disable receive and transmit in case someone left it running.
        */
        fccp->fcc_gfmr &= ~(FCC_GFMR_ENR | FCC_GFMR_ENT);
}

/* Initialize the I/O pins for the FCC Ethernet.
*/
static void __init
init_fcc_ioports(fcc_info_t *fip, volatile iop8260_t *io,
                                                volatile immap_t *immap)
{

        /* FCC1 pins are on port A/C.  FCC2/3 are port B/C.
        */
        if (fip->fc_proff == PROFF_FCC1) {
                /* Configure port A and C pins for FCC1 Ethernet.
                 */
                io->iop_pdira &= ~PA1_DIRA0;
                io->iop_pdira |= PA1_DIRA1;
                io->iop_psora &= ~PA1_PSORA0;
                io->iop_psora |= PA1_PSORA1;
                io->iop_ppara |= (PA1_DIRA0 | PA1_DIRA1);
        }
        if (fip->fc_proff == PROFF_FCC2) {
                /* Configure port B and C pins for FCC Ethernet.
                 */
                io->iop_pdirb &= ~PB2_DIRB0;
                io->iop_pdirb |= PB2_DIRB1;
                io->iop_psorb &= ~PB2_PSORB0;
                io->iop_psorb |= PB2_PSORB1;
                io->iop_pparb |= (PB2_DIRB0 | PB2_DIRB1);
        }
        if (fip->fc_proff == PROFF_FCC3) {
                /* Configure port B and C pins for FCC Ethernet.
                 */
                io->iop_pdirb &= ~PB3_DIRB0;
                io->iop_pdirb |= PB3_DIRB1;
                io->iop_psorb &= ~PB3_PSORB0;
                io->iop_psorb |= PB3_PSORB1;
                io->iop_pparb |= (PB3_DIRB0 | PB3_DIRB1);
        }

        /* Port C has clocks......
        */
        io->iop_psorc &= ~(fip->fc_trxclocks);
        io->iop_pdirc &= ~(fip->fc_trxclocks);
        io->iop_pparc |= fip->fc_trxclocks;

#ifdef  CONFIG_USE_MDIO
        /* ....and the MII serial clock/data.
        */
        io->iop_pdatc |= (fip->fc_mdio | fip->fc_mdck);
        io->iop_podrc &= ~(fip->fc_mdio | fip->fc_mdck);
        io->iop_pdirc |= (fip->fc_mdio | fip->fc_mdck);
        io->iop_pparc &= ~(fip->fc_mdio | fip->fc_mdck);
#endif  /* CONFIG_USE_MDIO */

        /* Configure Serial Interface clock routing.
         * First, clear all FCC bits to zero,
         * then set the ones we want.
         */
        immap->im_cpmux.cmx_fcr &= ~(fip->fc_clockmask);
        immap->im_cpmux.cmx_fcr |= fip->fc_clockroute;
}

static void __init
init_fcc_param(fcc_info_t *fip, struct net_device *dev,
                                                volatile immap_t *immap)
{
        unsigned char   *eap;
        unsigned long   mem_addr;
        bd_t            *bd;
        int             i, j;
        struct          fcc_enet_private *cep;
        volatile        fcc_enet_t      *ep;
        volatile        cbd_t           *bdp;
        volatile        cpm8260_t       *cp;

        cep = (struct fcc_enet_private *)(dev->priv);
        ep = cep->ep;
        cp = cpmp;

        bd = (bd_t *)__res;

        /* Zero the whole thing.....I must have missed some individually.
         * It works when I do this.
         */
        memset((char *)ep, 0, sizeof(fcc_enet_t));

        /* Allocate space for the buffer descriptors in the DP ram.
         * These are relative offsets in the DP ram address space.
         * Initialize base addresses for the buffer descriptors.
         */
#if 0
        /* I really want to do this, but for some reason it doesn't
         * work with the data cache enabled, so I allocate from the
         * main memory instead.
         */
        i = m8260_cpm_dpalloc(sizeof(cbd_t) * RX_RING_SIZE, 8);
        ep->fen_genfcc.fcc_rbase = (uint)&immap->im_dprambase[i];
        cep->rx_bd_base = (cbd_t *)&immap->im_dprambase[i];

        i = m8260_cpm_dpalloc(sizeof(cbd_t) * TX_RING_SIZE, 8);
        ep->fen_genfcc.fcc_tbase = (uint)&immap->im_dprambase[i];
        cep->tx_bd_base = (cbd_t *)&immap->im_dprambase[i];
#else
        cep->rx_bd_base = (cbd_t *)m8260_cpm_hostalloc(sizeof(cbd_t) * RX_RING_SIZE, 8);
        ep->fen_genfcc.fcc_rbase = __pa(cep->rx_bd_base);
        cep->tx_bd_base = (cbd_t *)m8260_cpm_hostalloc(sizeof(cbd_t) * TX_RING_SIZE, 8);
        ep->fen_genfcc.fcc_tbase = __pa(cep->tx_bd_base);
#endif

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

        ep->fen_genfcc.fcc_rstate = (CPMFCR_GBL | CPMFCR_EB) << 24;
        ep->fen_genfcc.fcc_tstate = (CPMFCR_GBL | CPMFCR_EB) << 24;

        /* Set maximum bytes per receive buffer.
         * It must be a multiple of 32.
         */
        ep->fen_genfcc.fcc_mrblr = PKT_MAXBLR_SIZE;

        /* Allocate space in the reserved FCC area of DPRAM for the
         * internal buffers.  No one uses this space (yet), so we
         * can do this.  Later, we will add resource management for
         * this area.
         */
        mem_addr = CPM_FCC_SPECIAL_BASE + (fip->fc_fccnum * 128);
        ep->fen_genfcc.fcc_riptr = mem_addr;
        ep->fen_genfcc.fcc_tiptr = mem_addr+32;
        ep->fen_padptr = mem_addr+64;
        memset((char *)(&(immap->im_dprambase[(mem_addr+64)])), 0x88, 32);

        ep->fen_genfcc.fcc_rbptr = 0;
        ep->fen_genfcc.fcc_tbptr = 0;
        ep->fen_genfcc.fcc_rcrc = 0;
        ep->fen_genfcc.fcc_tcrc = 0;
        ep->fen_genfcc.fcc_res1 = 0;
        ep->fen_genfcc.fcc_res2 = 0;

        ep->fen_camptr = 0;     /* CAM isn't used in this driver */

        /* Set CRC preset and mask.
        */
        ep->fen_cmask = 0xdebb20e3;
        ep->fen_cpres = 0xffffffff;

        ep->fen_crcec = 0;      /* CRC Error counter */
        ep->fen_alec = 0;       /* alignment error counter */
        ep->fen_disfc = 0;      /* discard frame counter */
        ep->fen_retlim = 15;    /* Retry limit threshold */
        ep->fen_pper = 0;       /* Normal persistence */

        /* Clear hash filter tables.
        */
        ep->fen_gaddrh = 0;
        ep->fen_gaddrl = 0;
        ep->fen_iaddrh = 0;
        ep->fen_iaddrl = 0;

        /* Clear the Out-of-sequence TxBD.
        */
        ep->fen_tfcstat = 0;
        ep->fen_tfclen = 0;
        ep->fen_tfcptr = 0;

        ep->fen_mflr = PKT_MAXBUF_SIZE;   /* maximum frame length register */
        ep->fen_minflr = PKT_MINBUF_SIZE;  /* minimum frame length register */

        /* Set Ethernet station address.
         *
         * This is supplied in the board information structure, so we
         * copy that into the controller.
         * So, far we have only been given one Ethernet address. We make
         * it unique by setting a few bits in the upper byte of the
         * non-static part of the address.
         */
        eap = (unsigned char *)&(ep->fen_paddrh);
        for (i=5; i>=0; i--) {
#ifdef CONFIG_SBC82xx
                if (i == 5) {
                        /* bd->bi_enetaddr holds the SCC0 address; the FCC
                           devices count up from there */
                        dev->dev_addr[i] = bd->bi_enetaddr[i] & ~3;
                        dev->dev_addr[i] += 1 + fip->fc_fccnum;
                        *eap++ = dev->dev_addr[i];
                }
#else
                if (i == 3) {
                        dev->dev_addr[i] = bd->bi_enetaddr[i];
                        dev->dev_addr[i] |= (1 << (7 - fip->fc_fccnum));
                        *eap++ = dev->dev_addr[i];
                }
#endif
                else {
                        *eap++ = dev->dev_addr[i] = bd->bi_enetaddr[i];
                }
        }

        ep->fen_taddrh = 0;
        ep->fen_taddrm = 0;
        ep->fen_taddrl = 0;

        ep->fen_maxd1 = PKT_MAXDMA_SIZE;        /* maximum DMA1 length */
        ep->fen_maxd2 = PKT_MAXDMA_SIZE;        /* maximum DMA2 length */

        /* Clear stat counters, in case we ever enable RMON.
        */
        ep->fen_octc = 0;
        ep->fen_colc = 0;
        ep->fen_broc = 0;
        ep->fen_mulc = 0;
        ep->fen_uspc = 0;
        ep->fen_frgc = 0;
        ep->fen_ospc = 0;
        ep->fen_jbrc = 0;
        ep->fen_p64c = 0;
        ep->fen_p65c = 0;
        ep->fen_p128c = 0;
        ep->fen_p256c = 0;
        ep->fen_p512c = 0;
        ep->fen_p1024c = 0;

        ep->fen_rfthr = 0;      /* Suggested by manual */
        ep->fen_rfcnt = 0;
        ep->fen_cftype = 0;

        /* Now allocate the host memory pages and initialize the
         * buffer descriptors.
         */
        bdp = cep->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_datlen = 0;
                bdp->cbd_bufaddr = 0;
                bdp++;
        }

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

        bdp = cep->rx_bd_base;
        for (i=0; i<FCC_ENET_RX_PAGES; i++) {

                /* Allocate a page.
                */
                mem_addr = __get_free_page(GFP_KERNEL);

                /* Initialize the BD for every fragment in the page.
                */
                for (j=0; j<FCC_ENET_RX_FRPPG; j++) {
                        bdp->cbd_sc = BD_ENET_RX_EMPTY | BD_ENET_RX_INTR;
                        bdp->cbd_datlen = 0;
                        bdp->cbd_bufaddr = __pa(mem_addr);
                        mem_addr += FCC_ENET_RX_FRSIZE;
                        bdp++;
                }
        }

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

        /* Let's re-initialize the channel now.  We have to do it later
         * than the manual describes because we have just now finished
         * the BD initialization.
         */
        cp->cp_cpcr = mk_cr_cmd(fip->fc_cpmpage, fip->fc_cpmblock, 0x0c,
                        CPM_CR_INIT_TRX) | CPM_CR_FLG;
        while (cp->cp_cpcr & CPM_CR_FLG);

        cep->skb_cur = cep->skb_dirty = 0;
        atomic_set(&cep->n_pkts, 0);
}

/* Let 'er rip.
*/
static void __init
init_fcc_startup(fcc_info_t *fip, struct net_device *dev)
{
        volatile fcc_t  *fccp;
        struct fcc_enet_private *cep;

        cep = (struct fcc_enet_private *)(dev->priv);
        fccp = cep->fccp;

        fccp->fcc_fcce = 0xffff;        /* Clear any pending events */

        /* Enable interrupts for transmit error, complete frame
         * received, and any transmit buffer we have also set the
         * interrupt flag.
         */
        fccp->fcc_fccm = (FCC_ENET_TXE | FCC_ENET_RXF | FCC_ENET_TXB);

        /* Install our interrupt handler.
        */
        if (request_irq(fip->fc_interrupt, fcc_enet_interrupt, 0,
                                                        "fenet", dev) < 0)
                printk("Can't get FCC IRQ %d\n", fip->fc_interrupt);

#ifdef  CONFIG_USE_MDIO
        if (request_irq(PHY_INTERRUPT, mii_link_interrupt, 0,
                                                        "mii", dev) < 0)
                printk("Can't get MII IRQ %d\n", fip->fc_interrupt);
#endif  /* CONFIG_USE_MDIO */

        /* Set GFMR to enable Ethernet operating mode.
         */
        fccp->fcc_gfmr = (FCC_GFMR_TCI | FCC_GFMR_MODE_ENET);

        /* Set sync/delimiters.
        */
        fccp->fcc_fdsr = 0xd555;

        /* Set protocol specific processing mode for Ethernet.
         * This has to be adjusted for Full Duplex operation after we can
         * determine how to detect that.
         */
        fccp->fcc_fpsmr = FCC_PSMR_ENCRC;

#ifdef CONFIG_ADS8260
        /* Enable the PHY.
        */
        ads_csr_addr[1] |= BCSR1_FETH_RST;      /* Remove reset */
        ads_csr_addr[1] &= ~BCSR1_FETHIEN;      /* Enable */
#endif

#if defined(CONFIG_USE_MDIO) || defined(CONFIG_TQM8260)
        /* start in full duplex mode, and negotiate speed
         */
        fcc_restart (dev, 1);
#else
        /* start in half duplex mode
         */
        fcc_restart (dev, 0);
#endif
}

#ifdef  CONFIG_USE_MDIO
/* MII command/status interface.
 * I'm not going to describe all of the details.  You can find the
 * protocol definition in many other places, including the data sheet
 * of most PHY parts.
 * I wonder what "they" were thinking (maybe weren't) when they leave
 * the I2C in the CPM but I have to toggle these bits......
 */

#define FCC_PDATC_MDIO(bit)                                     \
        if (bit)                                                \
                io->iop_pdatc |= fip->fc_mdio;                  \
        else                                                    \
                io->iop_pdatc &= ~fip->fc_mdio;

#define FCC_PDATC_MDC(bit)                                      \
        if (bit)                                                \
                io->iop_pdatc |= fip->fc_mdck;                  \
        else                                                    \
                io->iop_pdatc &= ~fip->fc_mdck;

static uint
mii_send_receive(fcc_info_t *fip, uint cmd)
{
        uint            retval;
        int             read_op, i, off;
        volatile        immap_t         *immap;
        volatile        iop8260_t       *io;

        immap = (immap_t *)IMAP_ADDR;
        io = &immap->im_ioport;

        io->iop_pdirc |= (fip->fc_mdio | fip->fc_mdck);

        read_op = ((cmd & 0xf0000000) == 0x60000000);

        /* Write preamble
         */
        for (i = 0; i < 32; i++)
        {
                FCC_PDATC_MDC(0);
                FCC_PDATC_MDIO(1);
                udelay(1);
                FCC_PDATC_MDC(1);
                udelay(1);
        }

        /* Write data
         */
        for (i = 0, off = 31; i < (read_op ? 14 : 32); i++, --off)
        {
                FCC_PDATC_MDC(0);
                FCC_PDATC_MDIO((cmd >> off) & 0x00000001);
                udelay(1);
                FCC_PDATC_MDC(1);
                udelay(1);
        }

        retval = cmd;

        if (read_op)
        {
                retval >>= 16;

                FCC_PDATC_MDC(0);
                io->iop_pdirc &= ~fip->fc_mdio;
                udelay(1);
                FCC_PDATC_MDC(1);
                udelay(1);
                FCC_PDATC_MDC(0);
                udelay(1);

                for (i = 0, off = 15; i < 16; i++, off--)
                {
                        FCC_PDATC_MDC(1);
                        retval <<= 1;
                        if (io->iop_pdatc & fip->fc_mdio)
                                retval++;
                        udelay(1);
                        FCC_PDATC_MDC(0);
                        udelay(1);
                }
        }

        io->iop_pdirc |= (fip->fc_mdio | fip->fc_mdck);

        for (i = 0; i < 32; i++)
        {
                FCC_PDATC_MDC(0);
                FCC_PDATC_MDIO(1);
                udelay(1);
                FCC_PDATC_MDC(1);
                udelay(1);
        }

        return retval;
}

static void
fcc_stop(struct net_device *dev)
{
        volatile fcc_t  *fccp;
        struct fcc_enet_private *fcp;

        fcp = (struct fcc_enet_private *)(dev->priv);
        fccp = fcp->fccp;

        /* Disable transmit/receive */
        fccp->fcc_gfmr &= ~(FCC_GFMR_ENR | FCC_GFMR_ENT);
}
#endif  /* CONFIG_USE_MDIO */

static void
fcc_restart(struct net_device *dev, int duplex)
{
        volatile fcc_t  *fccp;
        struct fcc_enet_private *fcp;

        fcp = (struct fcc_enet_private *)(dev->priv);
        fccp = fcp->fccp;

        if (duplex)
                fccp->fcc_fpsmr |= FCC_PSMR_FDE;
        else
                fccp->fcc_fpsmr &= ~FCC_PSMR_FDE;

        /* Enable transmit/receive */
        fccp->fcc_gfmr |= FCC_GFMR_ENR | FCC_GFMR_ENT;
}

static int
fcc_enet_open(struct net_device *dev)
{
        struct fcc_enet_private *fep = dev->priv;

#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;                                       /* Always succeed */
#endif  /* CONFIG_USE_MDIO */
}