Chinese: add translation of oops-tracing.txt

[pv_ops_mirror.git] / drivers / net / fec_mpc52xx.c

/*
 * Driver for the MPC5200 Fast Ethernet Controller
 *
 * Originally written by Dale Farnsworth <dfarnsworth@mvista.com> and
 * now maintained by Sylvain Munaut <tnt@246tNt.com>
 *
 * Copyright (C) 2007  Domen Puncer, Telargo, Inc.
 * Copyright (C) 2007  Sylvain Munaut <tnt@246tNt.com>
 * Copyright (C) 2003-2004  MontaVista, Software, Inc.
 *
 * This file is licensed under the terms of the GNU General Public License
 * version 2. This program is licensed "as is" without any warranty of any
 * kind, whether express or implied.
 *
 */

#include <linux/module.h>

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

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

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

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

#include "fec_mpc52xx.h"

#define DRIVER_NAME "mpc52xx-fec"

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

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

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

static void mpc52xx_fec_tx_timeout(struct net_device *dev)
{
        dev_warn(&dev->dev, "transmit timed out\n");

        mpc52xx_fec_reset(dev);

        dev->stats.tx_errors++;

        netif_wake_queue(dev);
}

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

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

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

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

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

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

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

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

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

static int mpc52xx_fec_alloc_rx_buffers(struct net_device *dev, struct bcom_task *rxtsk)
{
        while (!bcom_queue_full(rxtsk)) {
                struct sk_buff *skb;
                struct bcom_fec_bd *bd;

                skb = dev_alloc_skb(FEC_RX_BUFFER_SIZE);
                if (skb == NULL)
                        return -EAGAIN;

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

                bd = (struct bcom_fec_bd *)bcom_prepare_next_buffer(rxtsk);

                bd->status = FEC_RX_BUFFER_SIZE;
                bd->skb_pa = dma_map_single(&dev->dev, skb->data,
                                FEC_RX_BUFFER_SIZE, DMA_FROM_DEVICE);

                bcom_submit_next_buffer(rxtsk, skb);
        }

        return 0;
}

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

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

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

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

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

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

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

                if (priv->link == PHY_DOWN) {
                        new_state = 1;
                        priv->link = phydev->link;
                        netif_schedule(dev);
                        netif_carrier_on(dev);
                        netif_start_queue(dev);
                }

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

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

static int mpc52xx_fec_init_phy(struct net_device *dev)
{
        struct mpc52xx_fec_priv *priv = netdev_priv(dev);
        struct phy_device *phydev;
        char phy_id[BUS_ID_SIZE];

        snprintf(phy_id, BUS_ID_SIZE, PHY_ID_FMT,
                        (unsigned int)dev->base_addr, priv->phy_addr);

        priv->link = PHY_DOWN;
        priv->speed = 0;
        priv->duplex = -1;

        phydev = phy_connect(dev, phy_id, &mpc52xx_fec_adjust_link, 0, PHY_INTERFACE_MODE_MII);
        if (IS_ERR(phydev)) {
                dev_err(&dev->dev, "phy_connect failed\n");
                return PTR_ERR(phydev);
        }
        dev_info(&dev->dev, "attached phy %i to driver %s\n",
                        phydev->addr, phydev->drv->name);

        priv->phydev = phydev;

        return 0;
}

static int mpc52xx_fec_phy_start(struct net_device *dev)
{
        struct mpc52xx_fec_priv *priv = netdev_priv(dev);
        int err;

        if (!priv->has_phy)
                return 0;

        err = mpc52xx_fec_init_phy(dev);
        if (err) {
                dev_err(&dev->dev, "mpc52xx_fec_init_phy failed\n");
                return err;
        }

        /* reset phy - this also wakes it from PDOWN */
        phy_write(priv->phydev, MII_BMCR, BMCR_RESET);
        phy_start(priv->phydev);

        return 0;
}

static void mpc52xx_fec_phy_stop(struct net_device *dev)
{
        struct mpc52xx_fec_priv *priv = netdev_priv(dev);

        if (!priv->has_phy)
                return;

        phy_disconnect(priv->phydev);
        /* power down phy */
        phy_stop(priv->phydev);
        phy_write(priv->phydev, MII_BMCR, BMCR_PDOWN);
}

static int mpc52xx_fec_phy_mii_ioctl(struct mpc52xx_fec_priv *priv,
                struct mii_ioctl_data *mii_data, int cmd)
{
        if (!priv->has_phy)
                return -ENOTSUPP;

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

static void mpc52xx_fec_phy_hw_init(struct mpc52xx_fec_priv *priv)
{
        struct mpc52xx_fec __iomem *fec = priv->fec;

        if (!priv->has_phy)
                return;

        out_be32(&fec->mii_speed, priv->phy_speed);
}

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

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

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

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

        err = mpc52xx_fec_phy_start(dev);
        if (err)
                goto free_skbs;

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

        mpc52xx_fec_start(dev);

        netif_start_queue(dev);

        return 0;

 free_skbs:
        mpc52xx_fec_free_rx_buffers(dev, priv->rx_dmatsk);

 free_irqs:
        free_irq(priv->t_irq, dev);
 free_2irqs:
        free_irq(priv->r_irq, dev);
 free_ctrl_irq:
        free_irq(dev->irq, dev);
 out:

        return err;
}

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

        netif_stop_queue(dev);

        mpc52xx_fec_stop(dev);

        mpc52xx_fec_free_rx_buffers(dev, priv->rx_dmatsk);

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

        mpc52xx_fec_phy_stop(dev);

        return 0;
}

/* This will only be invoked if your driver is _not_ in XOFF state.
 * What this means is that you need not check it, and that this
 * invariant will hold if you make sure that the netif_*_queue()
 * calls are done at the proper times.
 */
static int mpc52xx_fec_hard_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
        struct mpc52xx_fec_priv *priv = netdev_priv(dev);
        struct bcom_fec_bd *bd;

        if (bcom_queue_full(priv->tx_dmatsk)) {
                if (net_ratelimit())
                        dev_err(&dev->dev, "transmit queue overrun\n");
                return 1;
        }

        spin_lock_irq(&priv->lock);
        dev->trans_start = jiffies;

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

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

        bcom_submit_next_buffer(priv->tx_dmatsk, skb);

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

        spin_unlock_irq(&priv->lock);

        return 0;
}

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

        spin_lock(&priv->lock);

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

                dev_kfree_skb_irq(skb);
        }

        netif_wake_queue(dev);

        spin_unlock(&priv->lock);

        return IRQ_HANDLED;
}

static irqreturn_t mpc52xx_fec_rx_interrupt(int irq, void *dev_id)
{
        struct net_device *dev = dev_id;
        struct mpc52xx_fec_priv *priv = netdev_priv(dev);

        while (bcom_buffer_done(priv->rx_dmatsk)) {
                struct sk_buff *skb;
                struct sk_buff *rskb;
                struct bcom_fec_bd *bd;
                u32 status;

                rskb = bcom_retrieve_buffer(priv->rx_dmatsk, &status,
                                (struct bcom_bd **)&bd);
                dma_unmap_single(&dev->dev, bd->skb_pa, rskb->len, DMA_FROM_DEVICE);

                /* Test for errors in received frame */
                if (status & BCOM_FEC_RX_BD_ERRORS) {
                        /* Drop packet and reuse the buffer */
                        bd = (struct bcom_fec_bd *)
                                bcom_prepare_next_buffer(priv->rx_dmatsk);

                        bd->status = FEC_RX_BUFFER_SIZE;
                        bd->skb_pa = dma_map_single(&dev->dev, rskb->data,
                                        FEC_RX_BUFFER_SIZE, DMA_FROM_DEVICE);

                        bcom_submit_next_buffer(priv->rx_dmatsk, rskb);

                        dev->stats.rx_dropped++;

                        continue;
                }

                /* skbs are allocated on open, so now we allocate a new one,
                 * and remove the old (with the packet) */
                skb = dev_alloc_skb(FEC_RX_BUFFER_SIZE);
                if (skb) {
                        /* Process the received skb */
                        int length = status & BCOM_FEC_RX_BD_LEN_MASK;

                        skb_put(rskb, length - 4);      /* length without CRC32 */

                        rskb->dev = dev;
                        rskb->protocol = eth_type_trans(rskb, dev);

                        netif_rx(rskb);
                        dev->last_rx = jiffies;
                } else {
                        /* Can't get a new one : reuse the same & drop pkt */
                        dev_notice(&dev->dev, "Memory squeeze, dropping packet.\n");
                        dev->stats.rx_dropped++;

                        skb = rskb;
                }

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

                bd->status = FEC_RX_BUFFER_SIZE;
                bd->skb_pa = dma_map_single(&dev->dev, skb->data,
                                FEC_RX_BUFFER_SIZE, DMA_FROM_DEVICE);

                bcom_submit_next_buffer(priv->rx_dmatsk, skb);
        }

        return IRQ_HANDLED;
}

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

        ievent = in_be32(&fec->ievent);

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

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

        if (ievent & ~(FEC_IEVENT_RFIFO_ERROR | FEC_IEVENT_XFIFO_ERROR)) {
                if (ievent & ~FEC_IEVENT_TFINT)
                        dev_dbg(&dev->dev, "ievent: %08x\n", ievent);
                return IRQ_HANDLED;
        }

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

        mpc52xx_fec_reset(dev);

        netif_wake_queue(dev);
        return IRQ_HANDLED;
}

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

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

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

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

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

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

        return stats;
}

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

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

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

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

        rx_control = in_be32(&fec->r_cntrl);

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

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

                        dmi = dev->mc_list;
                        for (i=0; i<dev->mc_count; i++) {
                                crc = ether_crc_le(6, dmi->dmi_addr) >> 26;
                                if (crc >= 32)
                                        gaddr1 |= 1 << (crc-32);
                                else
                                        gaddr2 |= 1 << crc;
                                dmi = dmi->next;
                        }
                        out_be32(&fec->gaddr1, gaddr1);
                        out_be32(&fec->gaddr2, gaddr2);
                }
        }
}

/**
 * mpc52xx_fec_hw_init
 * @dev: network device
 *
 * Setup various hardware setting, only needed once on start
 */
static void mpc52xx_fec_hw_init(struct net_device *dev)
{
        struct mpc52xx_fec_priv *priv = netdev_priv(dev);
        struct mpc52xx_fec __iomem *fec = priv->fec;
        int i;

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

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

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

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

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

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

        /* set phy speed.
         * this can't be done in phy driver, since it needs to be called
         * before fec stuff (even on resume) */
        mpc52xx_fec_phy_hw_init(priv);
}

/**
 * mpc52xx_fec_start
 * @dev: network device
 *
 * This function is called to start or restart the FEC during a link
 * change.  This happens on fifo errors or when switching between half
 * and full duplex.
 */
static void mpc52xx_fec_start(struct net_device *dev)
{
        struct mpc52xx_fec_priv *priv = netdev_priv(dev);
        struct mpc52xx_fec __iomem *fec = priv->fec;
        u32 rcntrl;
        u32 tcntrl;
        u32 tmp;

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

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

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

        mpc52xx_fec_set_multicast_list(dev);

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

        if (priv->has_phy)
                rcntrl |= FEC_RCNTRL_MII_MODE;

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

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

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

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

/**
 * mpc52xx_fec_stop
 * @dev: network device
 *
 * stop all activity on fec and empty dma buffers
 */
static void mpc52xx_fec_stop(struct net_device *dev)
{
        struct mpc52xx_fec_priv *priv = netdev_priv(dev);
        struct mpc52xx_fec __iomem *fec = priv->fec;
        unsigned long timeout;

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

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

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

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

        bcom_disable(priv->tx_dmatsk);

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

        return;
}

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

        mpc52xx_fec_stop(dev);

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

        mpc52xx_fec_free_rx_buffers(dev, priv->rx_dmatsk);

        mpc52xx_fec_hw_init(dev);

        phy_stop(priv->phydev);
        phy_write(priv->phydev, MII_BMCR, BMCR_RESET);
        phy_start(priv->phydev);

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

        mpc52xx_fec_alloc_rx_buffers(dev, priv->rx_dmatsk);

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

        mpc52xx_fec_start(dev);
}


/* ethtool interface */
static void mpc52xx_fec_get_drvinfo(struct net_device *dev,
                struct ethtool_drvinfo *info)
{
        strcpy(info->driver, DRIVER_NAME);
}

static int mpc52xx_fec_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
{
        struct mpc52xx_fec_priv *priv = netdev_priv(dev);
        return phy_ethtool_gset(priv->phydev, cmd);
}

static int mpc52xx_fec_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
{
        struct mpc52xx_fec_priv *priv = netdev_priv(dev);
        return phy_ethtool_sset(priv->phydev, cmd);
}

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

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

static const struct ethtool_ops mpc52xx_fec_ethtool_ops = {
        .get_drvinfo = mpc52xx_fec_get_drvinfo,
        .get_settings = mpc52xx_fec_get_settings,
        .set_settings = mpc52xx_fec_set_settings,
        .get_link = ethtool_op_get_link,
        .get_msglevel = mpc52xx_fec_get_msglevel,
        .set_msglevel = mpc52xx_fec_set_msglevel,
};


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

        return mpc52xx_fec_phy_mii_ioctl(priv, if_mii(rq), cmd);
}

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

static int __devinit
mpc52xx_fec_probe(struct of_device *op, const struct of_device_id *match)
{
        int rv;
        struct net_device *ndev;
        struct mpc52xx_fec_priv *priv = NULL;
        struct resource mem;
        const phandle *ph;

        phys_addr_t rx_fifo;
        phys_addr_t tx_fifo;

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

        priv = netdev_priv(ndev);

        /* Reserve FEC control zone */
        rv = of_address_to_resource(op->node, 0, &mem);
        if (rv) {
                printk(KERN_ERR DRIVER_NAME ": "
                                "Error while parsing device node resource\n" );
                return rv;
        }
        if ((mem.end - mem.start + 1) < sizeof(struct mpc52xx_fec)) {
                printk(KERN_ERR DRIVER_NAME
                        " - invalid resource size (%lx < %x), check mpc52xx_devices.c\n",
                        (unsigned long)(mem.end - mem.start + 1), sizeof(struct mpc52xx_fec));
                return -EINVAL;
        }

        if (!request_mem_region(mem.start, sizeof(struct mpc52xx_fec), DRIVER_NAME))
                return -EBUSY;

        /* Init ether ndev with what we have */
        ndev->open              = mpc52xx_fec_open;
        ndev->stop              = mpc52xx_fec_close;
        ndev->hard_start_xmit   = mpc52xx_fec_hard_start_xmit;
        ndev->do_ioctl          = mpc52xx_fec_ioctl;
        ndev->ethtool_ops       = &mpc52xx_fec_ethtool_ops;
        ndev->get_stats         = mpc52xx_fec_get_stats;
        ndev->set_mac_address   = mpc52xx_fec_set_mac_address;
        ndev->set_multicast_list = mpc52xx_fec_set_multicast_list;
        ndev->tx_timeout        = mpc52xx_fec_tx_timeout;
        ndev->watchdog_timeo    = FEC_WATCHDOG_TIMEOUT;
        ndev->base_addr         = mem.start;

        priv->t_irq = priv->r_irq = ndev->irq = NO_IRQ; /* IRQ are free for now */

        spin_lock_init(&priv->lock);

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

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

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

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

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

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

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

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

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

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

        /* is the phy present in device tree? */
        ph = of_get_property(op->node, "phy-handle", NULL);
        if (ph) {
                const unsigned int *prop;
                struct device_node *phy_dn;
                priv->has_phy = 1;

                phy_dn = of_find_node_by_phandle(*ph);
                prop = of_get_property(phy_dn, "reg", NULL);
                priv->phy_addr = *prop;

                of_node_put(phy_dn);

                /* Phy speed */
                priv->phy_speed = ((mpc52xx_find_ipb_freq(op->node) >> 20) / 5) << 1;
        } else {
                dev_info(&ndev->dev, "can't find \"phy-handle\" in device"
                                " tree, using 7-wire mode\n");
        }

        /* Hardware init */
        mpc52xx_fec_hw_init(ndev);

        mpc52xx_fec_reset_stats(ndev);

        SET_NETDEV_DEV(ndev, &op->dev);

        /* Register the new network device */
        rv = register_netdev(ndev);
        if (rv < 0)
                goto probe_error;

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

        return 0;


        /* Error handling - free everything that might be allocated */
probe_error:

        irq_dispose_mapping(ndev->irq);

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

        if (priv->fec)
                iounmap(priv->fec);

        release_mem_region(mem.start, sizeof(struct mpc52xx_fec));

        free_netdev(ndev);

        return rv;
}

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

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

        unregister_netdev(ndev);

        irq_dispose_mapping(ndev->irq);

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

        iounmap(priv->fec);

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

        free_netdev(ndev);

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

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

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

        return 0;
}

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

        mpc52xx_fec_hw_init(dev);
        mpc52xx_fec_reset_stats(dev);

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

        return 0;
}
#endif

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

MODULE_DEVICE_TABLE(of, mpc52xx_fec_match);

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


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

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

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


module_init(mpc52xx_fec_init);
module_exit(mpc52xx_fec_exit);

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