net: vlan: rename NETIF_F_HW_VLAN_* feature flags to NETIF_F_HW_VLAN_CTAG_*

[mirror_ubuntu-bionic-kernel.git] / drivers / net / ethernet / freescale / gianfar.c

/* drivers/net/ethernet/freescale/gianfar.c
 *
 * Gianfar Ethernet Driver
 * This driver is designed for the non-CPM ethernet controllers
 * on the 85xx and 83xx family of integrated processors
 * Based on 8260_io/fcc_enet.c
 *
 * Author: Andy Fleming
 * Maintainer: Kumar Gala
 * Modifier: Sandeep Gopalpet <sandeep.kumar@freescale.com>
 *
 * Copyright 2002-2009, 2011 Freescale Semiconductor, Inc.
 * Copyright 2007 MontaVista Software, Inc.
 *
 * This program is free software; you can redistribute  it and/or modify it
 * under  the terms of  the GNU General  Public License as published by the
 * Free Software Foundation;  either version 2 of the  License, or (at your
 * option) any later version.
 *
 *  Gianfar:  AKA Lambda Draconis, "Dragon"
 *  RA 11 31 24.2
 *  Dec +69 19 52
 *  V 3.84
 *  B-V +1.62
 *
 *  Theory of operation
 *
 *  The driver is initialized through of_device. Configuration information
 *  is therefore conveyed through an OF-style device tree.
 *
 *  The Gianfar Ethernet Controller uses a ring of buffer
 *  descriptors.  The beginning is indicated by a register
 *  pointing to the physical address of the start of the ring.
 *  The end is determined by a "wrap" bit being set in the
 *  last descriptor of the ring.
 *
 *  When a packet is received, the RXF bit in the
 *  IEVENT register is set, triggering an interrupt when the
 *  corresponding bit in the IMASK register is also set (if
 *  interrupt coalescing is active, then the interrupt may not
 *  happen immediately, but will wait until either a set number
 *  of frames or amount of time have passed).  In NAPI, the
 *  interrupt handler will signal there is work to be done, and
 *  exit. This method will start at the last known empty
 *  descriptor, and process every subsequent descriptor until there
 *  are none left with data (NAPI will stop after a set number of
 *  packets to give time to other tasks, but will eventually
 *  process all the packets).  The data arrives inside a
 *  pre-allocated skb, and so after the skb is passed up to the
 *  stack, a new skb must be allocated, and the address field in
 *  the buffer descriptor must be updated to indicate this new
 *  skb.
 *
 *  When the kernel requests that a packet be transmitted, the
 *  driver starts where it left off last time, and points the
 *  descriptor at the buffer which was passed in.  The driver
 *  then informs the DMA engine that there are packets ready to
 *  be transmitted.  Once the controller is finished transmitting
 *  the packet, an interrupt may be triggered (under the same
 *  conditions as for reception, but depending on the TXF bit).
 *  The driver then cleans up the buffer.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#define DEBUG

#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/errno.h>
#include <linux/unistd.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/init.h>
#include <linux/delay.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/if_vlan.h>
#include <linux/spinlock.h>
#include <linux/mm.h>
#include <linux/of_mdio.h>
#include <linux/of_platform.h>
#include <linux/ip.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#include <linux/in.h>
#include <linux/net_tstamp.h>

#include <asm/io.h>
#include <asm/reg.h>
#include <asm/irq.h>
#include <asm/uaccess.h>
#include <linux/module.h>
#include <linux/dma-mapping.h>
#include <linux/crc32.h>
#include <linux/mii.h>
#include <linux/phy.h>
#include <linux/phy_fixed.h>
#include <linux/of.h>
#include <linux/of_net.h>

#include "gianfar.h"

#define TX_TIMEOUT      (1*HZ)

const char gfar_driver_version[] = "1.3";

static int gfar_enet_open(struct net_device *dev);
static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev);
static void gfar_reset_task(struct work_struct *work);
static void gfar_timeout(struct net_device *dev);
static int gfar_close(struct net_device *dev);
struct sk_buff *gfar_new_skb(struct net_device *dev);
static void gfar_new_rxbdp(struct gfar_priv_rx_q *rx_queue, struct rxbd8 *bdp,
                           struct sk_buff *skb);
static int gfar_set_mac_address(struct net_device *dev);
static int gfar_change_mtu(struct net_device *dev, int new_mtu);
static irqreturn_t gfar_error(int irq, void *dev_id);
static irqreturn_t gfar_transmit(int irq, void *dev_id);
static irqreturn_t gfar_interrupt(int irq, void *dev_id);
static void adjust_link(struct net_device *dev);
static void init_registers(struct net_device *dev);
static int init_phy(struct net_device *dev);
static int gfar_probe(struct platform_device *ofdev);
static int gfar_remove(struct platform_device *ofdev);
static void free_skb_resources(struct gfar_private *priv);
static void gfar_set_multi(struct net_device *dev);
static void gfar_set_hash_for_addr(struct net_device *dev, u8 *addr);
static void gfar_configure_serdes(struct net_device *dev);
static int gfar_poll(struct napi_struct *napi, int budget);
#ifdef CONFIG_NET_POLL_CONTROLLER
static void gfar_netpoll(struct net_device *dev);
#endif
int gfar_clean_rx_ring(struct gfar_priv_rx_q *rx_queue, int rx_work_limit);
static void gfar_clean_tx_ring(struct gfar_priv_tx_q *tx_queue);
static void gfar_process_frame(struct net_device *dev, struct sk_buff *skb,
                               int amount_pull, struct napi_struct *napi);
void gfar_halt(struct net_device *dev);
static void gfar_halt_nodisable(struct net_device *dev);
void gfar_start(struct net_device *dev);
static void gfar_clear_exact_match(struct net_device *dev);
static void gfar_set_mac_for_addr(struct net_device *dev, int num,
                                  const u8 *addr);
static int gfar_ioctl(struct net_device *dev, struct ifreq *rq, int cmd);

MODULE_AUTHOR("Freescale Semiconductor, Inc");
MODULE_DESCRIPTION("Gianfar Ethernet Driver");
MODULE_LICENSE("GPL");

static void gfar_init_rxbdp(struct gfar_priv_rx_q *rx_queue, struct rxbd8 *bdp,
                            dma_addr_t buf)
{
        u32 lstatus;

        bdp->bufPtr = buf;

        lstatus = BD_LFLAG(RXBD_EMPTY | RXBD_INTERRUPT);
        if (bdp == rx_queue->rx_bd_base + rx_queue->rx_ring_size - 1)
                lstatus |= BD_LFLAG(RXBD_WRAP);

        eieio();

        bdp->lstatus = lstatus;
}

static int gfar_init_bds(struct net_device *ndev)
{
        struct gfar_private *priv = netdev_priv(ndev);
        struct gfar_priv_tx_q *tx_queue = NULL;
        struct gfar_priv_rx_q *rx_queue = NULL;
        struct txbd8 *txbdp;
        struct rxbd8 *rxbdp;
        int i, j;

        for (i = 0; i < priv->num_tx_queues; i++) {
                tx_queue = priv->tx_queue[i];
                /* Initialize some variables in our dev structure */
                tx_queue->num_txbdfree = tx_queue->tx_ring_size;
                tx_queue->dirty_tx = tx_queue->tx_bd_base;
                tx_queue->cur_tx = tx_queue->tx_bd_base;
                tx_queue->skb_curtx = 0;
                tx_queue->skb_dirtytx = 0;

                /* Initialize Transmit Descriptor Ring */
                txbdp = tx_queue->tx_bd_base;
                for (j = 0; j < tx_queue->tx_ring_size; j++) {
                        txbdp->lstatus = 0;
                        txbdp->bufPtr = 0;
                        txbdp++;
                }

                /* Set the last descriptor in the ring to indicate wrap */
                txbdp--;
                txbdp->status |= TXBD_WRAP;
        }

        for (i = 0; i < priv->num_rx_queues; i++) {
                rx_queue = priv->rx_queue[i];
                rx_queue->cur_rx = rx_queue->rx_bd_base;
                rx_queue->skb_currx = 0;
                rxbdp = rx_queue->rx_bd_base;

                for (j = 0; j < rx_queue->rx_ring_size; j++) {
                        struct sk_buff *skb = rx_queue->rx_skbuff[j];

                        if (skb) {
                                gfar_init_rxbdp(rx_queue, rxbdp,
                                                rxbdp->bufPtr);
                        } else {
                                skb = gfar_new_skb(ndev);
                                if (!skb) {
                                        netdev_err(ndev, "Can't allocate RX buffers\n");
                                        return -ENOMEM;
                                }
                                rx_queue->rx_skbuff[j] = skb;

                                gfar_new_rxbdp(rx_queue, rxbdp, skb);
                        }

                        rxbdp++;
                }

        }

        return 0;
}

static int gfar_alloc_skb_resources(struct net_device *ndev)
{
        void *vaddr;
        dma_addr_t addr;
        int i, j, k;
        struct gfar_private *priv = netdev_priv(ndev);
        struct device *dev = priv->dev;
        struct gfar_priv_tx_q *tx_queue = NULL;
        struct gfar_priv_rx_q *rx_queue = NULL;

        priv->total_tx_ring_size = 0;
        for (i = 0; i < priv->num_tx_queues; i++)
                priv->total_tx_ring_size += priv->tx_queue[i]->tx_ring_size;

        priv->total_rx_ring_size = 0;
        for (i = 0; i < priv->num_rx_queues; i++)
                priv->total_rx_ring_size += priv->rx_queue[i]->rx_ring_size;

        /* Allocate memory for the buffer descriptors */
        vaddr = dma_alloc_coherent(dev,
                                   (priv->total_tx_ring_size *
                                    sizeof(struct txbd8)) +
                                   (priv->total_rx_ring_size *
                                    sizeof(struct rxbd8)),
                                   &addr, GFP_KERNEL);
        if (!vaddr)
                return -ENOMEM;

        for (i = 0; i < priv->num_tx_queues; i++) {
                tx_queue = priv->tx_queue[i];
                tx_queue->tx_bd_base = vaddr;
                tx_queue->tx_bd_dma_base = addr;
                tx_queue->dev = ndev;
                /* enet DMA only understands physical addresses */
                addr  += sizeof(struct txbd8) * tx_queue->tx_ring_size;
                vaddr += sizeof(struct txbd8) * tx_queue->tx_ring_size;
        }

        /* Start the rx descriptor ring where the tx ring leaves off */
        for (i = 0; i < priv->num_rx_queues; i++) {
                rx_queue = priv->rx_queue[i];
                rx_queue->rx_bd_base = vaddr;
                rx_queue->rx_bd_dma_base = addr;
                rx_queue->dev = ndev;
                addr  += sizeof(struct rxbd8) * rx_queue->rx_ring_size;
                vaddr += sizeof(struct rxbd8) * rx_queue->rx_ring_size;
        }

        /* Setup the skbuff rings */
        for (i = 0; i < priv->num_tx_queues; i++) {
                tx_queue = priv->tx_queue[i];
                tx_queue->tx_skbuff =
                        kmalloc_array(tx_queue->tx_ring_size,
                                      sizeof(*tx_queue->tx_skbuff),
                                      GFP_KERNEL);
                if (!tx_queue->tx_skbuff)
                        goto cleanup;

                for (k = 0; k < tx_queue->tx_ring_size; k++)
                        tx_queue->tx_skbuff[k] = NULL;
        }

        for (i = 0; i < priv->num_rx_queues; i++) {
                rx_queue = priv->rx_queue[i];
                rx_queue->rx_skbuff =
                        kmalloc_array(rx_queue->rx_ring_size,
                                      sizeof(*rx_queue->rx_skbuff),
                                      GFP_KERNEL);
                if (!rx_queue->rx_skbuff)
                        goto cleanup;

                for (j = 0; j < rx_queue->rx_ring_size; j++)
                        rx_queue->rx_skbuff[j] = NULL;
        }

        if (gfar_init_bds(ndev))
                goto cleanup;

        return 0;

cleanup:
        free_skb_resources(priv);
        return -ENOMEM;
}

static void gfar_init_tx_rx_base(struct gfar_private *priv)
{
        struct gfar __iomem *regs = priv->gfargrp[0].regs;
        u32 __iomem *baddr;
        int i;

        baddr = &regs->tbase0;
        for (i = 0; i < priv->num_tx_queues; i++) {
                gfar_write(baddr, priv->tx_queue[i]->tx_bd_dma_base);
                baddr += 2;
        }

        baddr = &regs->rbase0;
        for (i = 0; i < priv->num_rx_queues; i++) {
                gfar_write(baddr, priv->rx_queue[i]->rx_bd_dma_base);
                baddr += 2;
        }
}

static void gfar_init_mac(struct net_device *ndev)
{
        struct gfar_private *priv = netdev_priv(ndev);
        struct gfar __iomem *regs = priv->gfargrp[0].regs;
        u32 rctrl = 0;
        u32 tctrl = 0;
        u32 attrs = 0;

        /* write the tx/rx base registers */
        gfar_init_tx_rx_base(priv);

        /* Configure the coalescing support */
        gfar_configure_coalescing_all(priv);

        /* set this when rx hw offload (TOE) functions are being used */
        priv->uses_rxfcb = 0;

        if (priv->rx_filer_enable) {
                rctrl |= RCTRL_FILREN;
                /* Program the RIR0 reg with the required distribution */
                gfar_write(&regs->rir0, DEFAULT_RIR0);
        }

        /* Restore PROMISC mode */
        if (ndev->flags & IFF_PROMISC)
                rctrl |= RCTRL_PROM;

        if (ndev->features & NETIF_F_RXCSUM) {
                rctrl |= RCTRL_CHECKSUMMING;
                priv->uses_rxfcb = 1;
        }

        if (priv->extended_hash) {
                rctrl |= RCTRL_EXTHASH;

                gfar_clear_exact_match(ndev);
                rctrl |= RCTRL_EMEN;
        }

        if (priv->padding) {
                rctrl &= ~RCTRL_PAL_MASK;
                rctrl |= RCTRL_PADDING(priv->padding);
        }

        /* Insert receive time stamps into padding alignment bytes */
        if (priv->device_flags & FSL_GIANFAR_DEV_HAS_TIMER) {
                rctrl &= ~RCTRL_PAL_MASK;
                rctrl |= RCTRL_PADDING(8);
                priv->padding = 8;
        }

        /* Enable HW time stamping if requested from user space */
        if (priv->hwts_rx_en) {
                rctrl |= RCTRL_PRSDEP_INIT | RCTRL_TS_ENABLE;
                priv->uses_rxfcb = 1;
        }

        if (ndev->features & NETIF_F_HW_VLAN_CTAG_RX) {
                rctrl |= RCTRL_VLEX | RCTRL_PRSDEP_INIT;
                priv->uses_rxfcb = 1;
        }

        /* Init rctrl based on our settings */
        gfar_write(&regs->rctrl, rctrl);

        if (ndev->features & NETIF_F_IP_CSUM)
                tctrl |= TCTRL_INIT_CSUM;

        if (priv->prio_sched_en)
                tctrl |= TCTRL_TXSCHED_PRIO;
        else {
                tctrl |= TCTRL_TXSCHED_WRRS;
                gfar_write(&regs->tr03wt, DEFAULT_WRRS_WEIGHT);
                gfar_write(&regs->tr47wt, DEFAULT_WRRS_WEIGHT);
        }

        gfar_write(&regs->tctrl, tctrl);

        /* Set the extraction length and index */
        attrs = ATTRELI_EL(priv->rx_stash_size) |
                ATTRELI_EI(priv->rx_stash_index);

        gfar_write(&regs->attreli, attrs);

        /* Start with defaults, and add stashing or locking
         * depending on the approprate variables
         */
        attrs = ATTR_INIT_SETTINGS;

        if (priv->bd_stash_en)
                attrs |= ATTR_BDSTASH;

        if (priv->rx_stash_size != 0)
                attrs |= ATTR_BUFSTASH;

        gfar_write(&regs->attr, attrs);

        gfar_write(&regs->fifo_tx_thr, priv->fifo_threshold);
        gfar_write(&regs->fifo_tx_starve, priv->fifo_starve);
        gfar_write(&regs->fifo_tx_starve_shutoff, priv->fifo_starve_off);
}

static struct net_device_stats *gfar_get_stats(struct net_device *dev)
{
        struct gfar_private *priv = netdev_priv(dev);
        unsigned long rx_packets = 0, rx_bytes = 0, rx_dropped = 0;
        unsigned long tx_packets = 0, tx_bytes = 0;
        int i;

        for (i = 0; i < priv->num_rx_queues; i++) {
                rx_packets += priv->rx_queue[i]->stats.rx_packets;
                rx_bytes   += priv->rx_queue[i]->stats.rx_bytes;
                rx_dropped += priv->rx_queue[i]->stats.rx_dropped;
        }

        dev->stats.rx_packets = rx_packets;
        dev->stats.rx_bytes   = rx_bytes;
        dev->stats.rx_dropped = rx_dropped;

        for (i = 0; i < priv->num_tx_queues; i++) {
                tx_bytes += priv->tx_queue[i]->stats.tx_bytes;
                tx_packets += priv->tx_queue[i]->stats.tx_packets;
        }

        dev->stats.tx_bytes   = tx_bytes;
        dev->stats.tx_packets = tx_packets;

        return &dev->stats;
}

static const struct net_device_ops gfar_netdev_ops = {
        .ndo_open = gfar_enet_open,
        .ndo_start_xmit = gfar_start_xmit,
        .ndo_stop = gfar_close,
        .ndo_change_mtu = gfar_change_mtu,
        .ndo_set_features = gfar_set_features,
        .ndo_set_rx_mode = gfar_set_multi,
        .ndo_tx_timeout = gfar_timeout,
        .ndo_do_ioctl = gfar_ioctl,
        .ndo_get_stats = gfar_get_stats,
        .ndo_set_mac_address = eth_mac_addr,
        .ndo_validate_addr = eth_validate_addr,
#ifdef CONFIG_NET_POLL_CONTROLLER
        .ndo_poll_controller = gfar_netpoll,
#endif
};

void lock_rx_qs(struct gfar_private *priv)
{
        int i;

        for (i = 0; i < priv->num_rx_queues; i++)
                spin_lock(&priv->rx_queue[i]->rxlock);
}

void lock_tx_qs(struct gfar_private *priv)
{
        int i;

        for (i = 0; i < priv->num_tx_queues; i++)
                spin_lock(&priv->tx_queue[i]->txlock);
}

void unlock_rx_qs(struct gfar_private *priv)
{
        int i;

        for (i = 0; i < priv->num_rx_queues; i++)
                spin_unlock(&priv->rx_queue[i]->rxlock);
}

void unlock_tx_qs(struct gfar_private *priv)
{
        int i;

        for (i = 0; i < priv->num_tx_queues; i++)
                spin_unlock(&priv->tx_queue[i]->txlock);
}

static void free_tx_pointers(struct gfar_private *priv)
{
        int i;

        for (i = 0; i < priv->num_tx_queues; i++)
                kfree(priv->tx_queue[i]);
}

static void free_rx_pointers(struct gfar_private *priv)
{
        int i;

        for (i = 0; i < priv->num_rx_queues; i++)
                kfree(priv->rx_queue[i]);
}

static void unmap_group_regs(struct gfar_private *priv)
{
        int i;

        for (i = 0; i < MAXGROUPS; i++)
                if (priv->gfargrp[i].regs)
                        iounmap(priv->gfargrp[i].regs);
}

static void free_gfar_dev(struct gfar_private *priv)
{
        int i, j;

        for (i = 0; i < priv->num_grps; i++)
                for (j = 0; j < GFAR_NUM_IRQS; j++) {
                        kfree(priv->gfargrp[i].irqinfo[j]);
                        priv->gfargrp[i].irqinfo[j] = NULL;
                }

        free_netdev(priv->ndev);
}

static void disable_napi(struct gfar_private *priv)
{
        int i;

        for (i = 0; i < priv->num_grps; i++)
                napi_disable(&priv->gfargrp[i].napi);
}

static void enable_napi(struct gfar_private *priv)
{
        int i;

        for (i = 0; i < priv->num_grps; i++)
                napi_enable(&priv->gfargrp[i].napi);
}

static int gfar_parse_group(struct device_node *np,
                            struct gfar_private *priv, const char *model)
{
        struct gfar_priv_grp *grp = &priv->gfargrp[priv->num_grps];
        u32 *queue_mask;
        int i;

        for (i = 0; i < GFAR_NUM_IRQS; i++) {
                grp->irqinfo[i] = kzalloc(sizeof(struct gfar_irqinfo),
                                          GFP_KERNEL);
                if (!grp->irqinfo[i])
                        return -ENOMEM;
        }

        grp->regs = of_iomap(np, 0);
        if (!grp->regs)
                return -ENOMEM;

        gfar_irq(grp, TX)->irq = irq_of_parse_and_map(np, 0);

        /* If we aren't the FEC we have multiple interrupts */
        if (model && strcasecmp(model, "FEC")) {
                gfar_irq(grp, RX)->irq = irq_of_parse_and_map(np, 1);
                gfar_irq(grp, ER)->irq = irq_of_parse_and_map(np, 2);
                if (gfar_irq(grp, TX)->irq == NO_IRQ ||
                    gfar_irq(grp, RX)->irq == NO_IRQ ||
                    gfar_irq(grp, ER)->irq == NO_IRQ)
                        return -EINVAL;
        }

        grp->grp_id = priv->num_grps;
        grp->priv = priv;
        spin_lock_init(&grp->grplock);
        if (priv->mode == MQ_MG_MODE) {
                queue_mask = (u32 *)of_get_property(np, "fsl,rx-bit-map", NULL);
                grp->rx_bit_map = queue_mask ?
                        *queue_mask : (DEFAULT_MAPPING >> priv->num_grps);
                queue_mask = (u32 *)of_get_property(np, "fsl,tx-bit-map", NULL);
                grp->tx_bit_map = queue_mask ?
                        *queue_mask : (DEFAULT_MAPPING >> priv->num_grps);
        } else {
                grp->rx_bit_map = 0xFF;
                grp->tx_bit_map = 0xFF;
        }
        priv->num_grps++;

        return 0;
}

static int gfar_of_init(struct platform_device *ofdev, struct net_device **pdev)
{
        const char *model;
        const char *ctype;
        const void *mac_addr;
        int err = 0, i;
        struct net_device *dev = NULL;
        struct gfar_private *priv = NULL;
        struct device_node *np = ofdev->dev.of_node;
        struct device_node *child = NULL;
        const u32 *stash;
        const u32 *stash_len;
        const u32 *stash_idx;
        unsigned int num_tx_qs, num_rx_qs;
        u32 *tx_queues, *rx_queues;

        if (!np || !of_device_is_available(np))
                return -ENODEV;

        /* parse the num of tx and rx queues */
        tx_queues = (u32 *)of_get_property(np, "fsl,num_tx_queues", NULL);
        num_tx_qs = tx_queues ? *tx_queues : 1;

        if (num_tx_qs > MAX_TX_QS) {
                pr_err("num_tx_qs(=%d) greater than MAX_TX_QS(=%d)\n",
                       num_tx_qs, MAX_TX_QS);
                pr_err("Cannot do alloc_etherdev, aborting\n");
                return -EINVAL;
        }

        rx_queues = (u32 *)of_get_property(np, "fsl,num_rx_queues", NULL);
        num_rx_qs = rx_queues ? *rx_queues : 1;

        if (num_rx_qs > MAX_RX_QS) {
                pr_err("num_rx_qs(=%d) greater than MAX_RX_QS(=%d)\n",
                       num_rx_qs, MAX_RX_QS);
                pr_err("Cannot do alloc_etherdev, aborting\n");
                return -EINVAL;
        }

        *pdev = alloc_etherdev_mq(sizeof(*priv), num_tx_qs);
        dev = *pdev;
        if (NULL == dev)
                return -ENOMEM;

        priv = netdev_priv(dev);
        priv->ndev = dev;

        priv->num_tx_queues = num_tx_qs;
        netif_set_real_num_rx_queues(dev, num_rx_qs);
        priv->num_rx_queues = num_rx_qs;
        priv->num_grps = 0x0;

        /* Init Rx queue filer rule set linked list */
        INIT_LIST_HEAD(&priv->rx_list.list);
        priv->rx_list.count = 0;
        mutex_init(&priv->rx_queue_access);

        model = of_get_property(np, "model", NULL);

        for (i = 0; i < MAXGROUPS; i++)
                priv->gfargrp[i].regs = NULL;

        /* Parse and initialize group specific information */
        if (of_device_is_compatible(np, "fsl,etsec2")) {
                priv->mode = MQ_MG_MODE;
                for_each_child_of_node(np, child) {
                        err = gfar_parse_group(child, priv, model);
                        if (err)
                                goto err_grp_init;
                }
        } else {
                priv->mode = SQ_SG_MODE;
                err = gfar_parse_group(np, priv, model);
                if (err)
                        goto err_grp_init;
        }

        for (i = 0; i < priv->num_tx_queues; i++)
                priv->tx_queue[i] = NULL;
        for (i = 0; i < priv->num_rx_queues; i++)
                priv->rx_queue[i] = NULL;

        for (i = 0; i < priv->num_tx_queues; i++) {
                priv->tx_queue[i] = kzalloc(sizeof(struct gfar_priv_tx_q),
                                            GFP_KERNEL);
                if (!priv->tx_queue[i]) {
                        err = -ENOMEM;
                        goto tx_alloc_failed;
                }
                priv->tx_queue[i]->tx_skbuff = NULL;
                priv->tx_queue[i]->qindex = i;
                priv->tx_queue[i]->dev = dev;
                spin_lock_init(&(priv->tx_queue[i]->txlock));
        }

        for (i = 0; i < priv->num_rx_queues; i++) {
                priv->rx_queue[i] = kzalloc(sizeof(struct gfar_priv_rx_q),
                                            GFP_KERNEL);
                if (!priv->rx_queue[i]) {
                        err = -ENOMEM;
                        goto rx_alloc_failed;
                }
                priv->rx_queue[i]->rx_skbuff = NULL;
                priv->rx_queue[i]->qindex = i;
                priv->rx_queue[i]->dev = dev;
                spin_lock_init(&(priv->rx_queue[i]->rxlock));
        }


        stash = of_get_property(np, "bd-stash", NULL);

        if (stash) {
                priv->device_flags |= FSL_GIANFAR_DEV_HAS_BD_STASHING;
                priv->bd_stash_en = 1;
        }

        stash_len = of_get_property(np, "rx-stash-len", NULL);

        if (stash_len)
                priv->rx_stash_size = *stash_len;

        stash_idx = of_get_property(np, "rx-stash-idx", NULL);

        if (stash_idx)
                priv->rx_stash_index = *stash_idx;

        if (stash_len || stash_idx)
                priv->device_flags |= FSL_GIANFAR_DEV_HAS_BUF_STASHING;

        mac_addr = of_get_mac_address(np);

        if (mac_addr)
                memcpy(dev->dev_addr, mac_addr, ETH_ALEN);

        if (model && !strcasecmp(model, "TSEC"))
                priv->device_flags = FSL_GIANFAR_DEV_HAS_GIGABIT |
                                     FSL_GIANFAR_DEV_HAS_COALESCE |
                                     FSL_GIANFAR_DEV_HAS_RMON |
                                     FSL_GIANFAR_DEV_HAS_MULTI_INTR;

        if (model && !strcasecmp(model, "eTSEC"))
                priv->device_flags = FSL_GIANFAR_DEV_HAS_GIGABIT |
                                     FSL_GIANFAR_DEV_HAS_COALESCE |
                                     FSL_GIANFAR_DEV_HAS_RMON |
                                     FSL_GIANFAR_DEV_HAS_MULTI_INTR |
                                     FSL_GIANFAR_DEV_HAS_PADDING |
                                     FSL_GIANFAR_DEV_HAS_CSUM |
                                     FSL_GIANFAR_DEV_HAS_VLAN |
                                     FSL_GIANFAR_DEV_HAS_MAGIC_PACKET |
                                     FSL_GIANFAR_DEV_HAS_EXTENDED_HASH |
                                     FSL_GIANFAR_DEV_HAS_TIMER;

        ctype = of_get_property(np, "phy-connection-type", NULL);

        /* We only care about rgmii-id.  The rest are autodetected */
        if (ctype && !strcmp(ctype, "rgmii-id"))
                priv->interface = PHY_INTERFACE_MODE_RGMII_ID;
        else
                priv->interface = PHY_INTERFACE_MODE_MII;

        if (of_get_property(np, "fsl,magic-packet", NULL))
                priv->device_flags |= FSL_GIANFAR_DEV_HAS_MAGIC_PACKET;

        priv->phy_node = of_parse_phandle(np, "phy-handle", 0);

        /* Find the TBI PHY.  If it's not there, we don't support SGMII */
        priv->tbi_node = of_parse_phandle(np, "tbi-handle", 0);

        return 0;

rx_alloc_failed:
        free_rx_pointers(priv);
tx_alloc_failed:
        free_tx_pointers(priv);
err_grp_init:
        unmap_group_regs(priv);
        free_gfar_dev(priv);
        return err;
}

static int gfar_hwtstamp_ioctl(struct net_device *netdev,
                               struct ifreq *ifr, int cmd)
{
        struct hwtstamp_config config;
        struct gfar_private *priv = netdev_priv(netdev);

        if (copy_from_user(&config, ifr->ifr_data, sizeof(config)))
                return -EFAULT;

        /* reserved for future extensions */
        if (config.flags)
                return -EINVAL;

        switch (config.tx_type) {
        case HWTSTAMP_TX_OFF:
                priv->hwts_tx_en = 0;
                break;
        case HWTSTAMP_TX_ON:
                if (!(priv->device_flags & FSL_GIANFAR_DEV_HAS_TIMER))
                        return -ERANGE;
                priv->hwts_tx_en = 1;
                break;
        default:
                return -ERANGE;
        }

        switch (config.rx_filter) {
        case HWTSTAMP_FILTER_NONE:
                if (priv->hwts_rx_en) {
                        stop_gfar(netdev);
                        priv->hwts_rx_en = 0;
                        startup_gfar(netdev);
                }
                break;
        default:
                if (!(priv->device_flags & FSL_GIANFAR_DEV_HAS_TIMER))
                        return -ERANGE;
                if (!priv->hwts_rx_en) {
                        stop_gfar(netdev);
                        priv->hwts_rx_en = 1;
                        startup_gfar(netdev);
                }
                config.rx_filter = HWTSTAMP_FILTER_ALL;
                break;
        }

        return copy_to_user(ifr->ifr_data, &config, sizeof(config)) ?
                -EFAULT : 0;
}

/* Ioctl MII Interface */
static int gfar_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
{
        struct gfar_private *priv = netdev_priv(dev);

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

        if (cmd == SIOCSHWTSTAMP)
                return gfar_hwtstamp_ioctl(dev, rq, cmd);

        if (!priv->phydev)
                return -ENODEV;

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

static unsigned int reverse_bitmap(unsigned int bit_map, unsigned int max_qs)
{
        unsigned int new_bit_map = 0x0;
        int mask = 0x1 << (max_qs - 1), i;

        for (i = 0; i < max_qs; i++) {
                if (bit_map & mask)
                        new_bit_map = new_bit_map + (1 << i);
                mask = mask >> 0x1;
        }
        return new_bit_map;
}

static u32 cluster_entry_per_class(struct gfar_private *priv, u32 rqfar,
                                   u32 class)
{
        u32 rqfpr = FPR_FILER_MASK;
        u32 rqfcr = 0x0;

        rqfar--;
        rqfcr = RQFCR_CLE | RQFCR_PID_MASK | RQFCR_CMP_EXACT;
        priv->ftp_rqfpr[rqfar] = rqfpr;
        priv->ftp_rqfcr[rqfar] = rqfcr;
        gfar_write_filer(priv, rqfar, rqfcr, rqfpr);

        rqfar--;
        rqfcr = RQFCR_CMP_NOMATCH;
        priv->ftp_rqfpr[rqfar] = rqfpr;
        priv->ftp_rqfcr[rqfar] = rqfcr;
        gfar_write_filer(priv, rqfar, rqfcr, rqfpr);

        rqfar--;
        rqfcr = RQFCR_CMP_EXACT | RQFCR_PID_PARSE | RQFCR_CLE | RQFCR_AND;
        rqfpr = class;
        priv->ftp_rqfcr[rqfar] = rqfcr;
        priv->ftp_rqfpr[rqfar] = rqfpr;
        gfar_write_filer(priv, rqfar, rqfcr, rqfpr);

        rqfar--;
        rqfcr = RQFCR_CMP_EXACT | RQFCR_PID_MASK | RQFCR_AND;
        rqfpr = class;
        priv->ftp_rqfcr[rqfar] = rqfcr;
        priv->ftp_rqfpr[rqfar] = rqfpr;
        gfar_write_filer(priv, rqfar, rqfcr, rqfpr);

        return rqfar;
}

static void gfar_init_filer_table(struct gfar_private *priv)
{
        int i = 0x0;
        u32 rqfar = MAX_FILER_IDX;
        u32 rqfcr = 0x0;
        u32 rqfpr = FPR_FILER_MASK;

        /* Default rule */
        rqfcr = RQFCR_CMP_MATCH;
        priv->ftp_rqfcr[rqfar] = rqfcr;
        priv->ftp_rqfpr[rqfar] = rqfpr;
        gfar_write_filer(priv, rqfar, rqfcr, rqfpr);

        rqfar = cluster_entry_per_class(priv, rqfar, RQFPR_IPV6);
        rqfar = cluster_entry_per_class(priv, rqfar, RQFPR_IPV6 | RQFPR_UDP);
        rqfar = cluster_entry_per_class(priv, rqfar, RQFPR_IPV6 | RQFPR_TCP);
        rqfar = cluster_entry_per_class(priv, rqfar, RQFPR_IPV4);
        rqfar = cluster_entry_per_class(priv, rqfar, RQFPR_IPV4 | RQFPR_UDP);
        rqfar = cluster_entry_per_class(priv, rqfar, RQFPR_IPV4 | RQFPR_TCP);

        /* cur_filer_idx indicated the first non-masked rule */
        priv->cur_filer_idx = rqfar;

        /* Rest are masked rules */
        rqfcr = RQFCR_CMP_NOMATCH;
        for (i = 0; i < rqfar; i++) {
                priv->ftp_rqfcr[i] = rqfcr;
                priv->ftp_rqfpr[i] = rqfpr;
                gfar_write_filer(priv, i, rqfcr, rqfpr);
        }
}

static void gfar_detect_errata(struct gfar_private *priv)
{
        struct device *dev = &priv->ofdev->dev;
        unsigned int pvr = mfspr(SPRN_PVR);
        unsigned int svr = mfspr(SPRN_SVR);
        unsigned int mod = (svr >> 16) & 0xfff6; /* w/o E suffix */
        unsigned int rev = svr & 0xffff;

        /* MPC8313 Rev 2.0 and higher; All MPC837x */
        if ((pvr == 0x80850010 && mod == 0x80b0 && rev >= 0x0020) ||
            (pvr == 0x80861010 && (mod & 0xfff9) == 0x80c0))
                priv->errata |= GFAR_ERRATA_74;

        /* MPC8313 and MPC837x all rev */
        if ((pvr == 0x80850010 && mod == 0x80b0) ||
            (pvr == 0x80861010 && (mod & 0xfff9) == 0x80c0))
                priv->errata |= GFAR_ERRATA_76;

        /* MPC8313 and MPC837x all rev */
        if ((pvr == 0x80850010 && mod == 0x80b0) ||
            (pvr == 0x80861010 && (mod & 0xfff9) == 0x80c0))
                priv->errata |= GFAR_ERRATA_A002;

        /* MPC8313 Rev < 2.0, MPC8548 rev 2.0 */
        if ((pvr == 0x80850010 && mod == 0x80b0 && rev < 0x0020) ||
            (pvr == 0x80210020 && mod == 0x8030 && rev == 0x0020))
                priv->errata |= GFAR_ERRATA_12;

        if (priv->errata)
                dev_info(dev, "enabled errata workarounds, flags: 0x%x\n",
                         priv->errata);
}

/* Set up the ethernet device structure, private data,
 * and anything else we need before we start
 */
static int gfar_probe(struct platform_device *ofdev)
{
        u32 tempval;
        struct net_device *dev = NULL;
        struct gfar_private *priv = NULL;
        struct gfar __iomem *regs = NULL;
        int err = 0, i, grp_idx = 0;
        u32 rstat = 0, tstat = 0, rqueue = 0, tqueue = 0;
        u32 isrg = 0;
        u32 __iomem *baddr;

        err = gfar_of_init(ofdev, &dev);

        if (err)
                return err;

        priv = netdev_priv(dev);
        priv->ndev = dev;
        priv->ofdev = ofdev;
        priv->dev = &ofdev->dev;
        SET_NETDEV_DEV(dev, &ofdev->dev);

        spin_lock_init(&priv->bflock);
        INIT_WORK(&priv->reset_task, gfar_reset_task);

        dev_set_drvdata(&ofdev->dev, priv);
        regs = priv->gfargrp[0].regs;

        gfar_detect_errata(priv);

        /* Stop the DMA engine now, in case it was running before
         * (The firmware could have used it, and left it running).
         */
        gfar_halt(dev);

        /* Reset MAC layer */
        gfar_write(&regs->maccfg1, MACCFG1_SOFT_RESET);

        /* We need to delay at least 3 TX clocks */
        udelay(2);

        tempval = (MACCFG1_TX_FLOW | MACCFG1_RX_FLOW);
        gfar_write(&regs->maccfg1, tempval);

        /* Initialize MACCFG2. */
        tempval = MACCFG2_INIT_SETTINGS;
        if (gfar_has_errata(priv, GFAR_ERRATA_74))
                tempval |= MACCFG2_HUGEFRAME | MACCFG2_LENGTHCHECK;
        gfar_write(&regs->maccfg2, tempval);

        /* Initialize ECNTRL */
        gfar_write(&regs->ecntrl, ECNTRL_INIT_SETTINGS);

        /* Set the dev->base_addr to the gfar reg region */
        dev->base_addr = (unsigned long) regs;

        /* Fill in the dev structure */
        dev->watchdog_timeo = TX_TIMEOUT;
        dev->mtu = 1500;
        dev->netdev_ops = &gfar_netdev_ops;
        dev->ethtool_ops = &gfar_ethtool_ops;

        /* Register for napi ...We are registering NAPI for each grp */
        for (i = 0; i < priv->num_grps; i++)
                netif_napi_add(dev, &priv->gfargrp[i].napi, gfar_poll,
                               GFAR_DEV_WEIGHT);

        if (priv->device_flags & FSL_GIANFAR_DEV_HAS_CSUM) {
                dev->hw_features = NETIF_F_IP_CSUM | NETIF_F_SG |
                                   NETIF_F_RXCSUM;
                dev->features |= NETIF_F_IP_CSUM | NETIF_F_SG |
                                 NETIF_F_RXCSUM | NETIF_F_HIGHDMA;
        }

        if (priv->device_flags & FSL_GIANFAR_DEV_HAS_VLAN) {
                dev->hw_features |= NETIF_F_HW_VLAN_CTAG_TX |
                                    NETIF_F_HW_VLAN_CTAG_RX;
                dev->features |= NETIF_F_HW_VLAN_CTAG_RX;
        }

        if (priv->device_flags & FSL_GIANFAR_DEV_HAS_EXTENDED_HASH) {
                priv->extended_hash = 1;
                priv->hash_width = 9;

                priv->hash_regs[0] = &regs->igaddr0;
                priv->hash_regs[1] = &regs->igaddr1;
                priv->hash_regs[2] = &regs->igaddr2;
                priv->hash_regs[3] = &regs->igaddr3;
                priv->hash_regs[4] = &regs->igaddr4;
                priv->hash_regs[5] = &regs->igaddr5;
                priv->hash_regs[6] = &regs->igaddr6;
                priv->hash_regs[7] = &regs->igaddr7;
                priv->hash_regs[8] = &regs->gaddr0;
                priv->hash_regs[9] = &regs->gaddr1;
                priv->hash_regs[10] = &regs->gaddr2;
                priv->hash_regs[11] = &regs->gaddr3;
                priv->hash_regs[12] = &regs->gaddr4;
                priv->hash_regs[13] = &regs->gaddr5;
                priv->hash_regs[14] = &regs->gaddr6;
                priv->hash_regs[15] = &regs->gaddr7;

        } else {
                priv->extended_hash = 0;
                priv->hash_width = 8;

                priv->hash_regs[0] = &regs->gaddr0;
                priv->hash_regs[1] = &regs->gaddr1;
                priv->hash_regs[2] = &regs->gaddr2;
                priv->hash_regs[3] = &regs->gaddr3;
                priv->hash_regs[4] = &regs->gaddr4;
                priv->hash_regs[5] = &regs->gaddr5;
                priv->hash_regs[6] = &regs->gaddr6;
                priv->hash_regs[7] = &regs->gaddr7;
        }

        if (priv->device_flags & FSL_GIANFAR_DEV_HAS_PADDING)
                priv->padding = DEFAULT_PADDING;
        else
                priv->padding = 0;

        if (dev->features & NETIF_F_IP_CSUM ||
            priv->device_flags & FSL_GIANFAR_DEV_HAS_TIMER)
                dev->needed_headroom = GMAC_FCB_LEN;

        /* Program the isrg regs only if number of grps > 1 */
        if (priv->num_grps > 1) {
                baddr = &regs->isrg0;
                for (i = 0; i < priv->num_grps; i++) {
                        isrg |= (priv->gfargrp[i].rx_bit_map << ISRG_SHIFT_RX);
                        isrg |= (priv->gfargrp[i].tx_bit_map << ISRG_SHIFT_TX);
                        gfar_write(baddr, isrg);
                        baddr++;
                        isrg = 0x0;
                }
        }

        /* Need to reverse the bit maps as  bit_map's MSB is q0
         * but, for_each_set_bit parses from right to left, which
         * basically reverses the queue numbers
         */
        for (i = 0; i< priv->num_grps; i++) {
                priv->gfargrp[i].tx_bit_map =
                        reverse_bitmap(priv->gfargrp[i].tx_bit_map, MAX_TX_QS);
                priv->gfargrp[i].rx_bit_map =
                        reverse_bitmap(priv->gfargrp[i].rx_bit_map, MAX_RX_QS);
        }

        /* Calculate RSTAT, TSTAT, RQUEUE and TQUEUE values,
         * also assign queues to groups
         */
        for (grp_idx = 0; grp_idx < priv->num_grps; grp_idx++) {
                priv->gfargrp[grp_idx].num_rx_queues = 0x0;

                for_each_set_bit(i, &priv->gfargrp[grp_idx].rx_bit_map,
                                 priv->num_rx_queues) {
                        priv->gfargrp[grp_idx].num_rx_queues++;
                        priv->rx_queue[i]->grp = &priv->gfargrp[grp_idx];
                        rstat = rstat | (RSTAT_CLEAR_RHALT >> i);
                        rqueue = rqueue | ((RQUEUE_EN0 | RQUEUE_EX0) >> i);
                }
                priv->gfargrp[grp_idx].num_tx_queues = 0x0;

                for_each_set_bit(i, &priv->gfargrp[grp_idx].tx_bit_map,
                                 priv->num_tx_queues) {
                        priv->gfargrp[grp_idx].num_tx_queues++;
                        priv->tx_queue[i]->grp = &priv->gfargrp[grp_idx];
                        tstat = tstat | (TSTAT_CLEAR_THALT >> i);
                        tqueue = tqueue | (TQUEUE_EN0 >> i);
                }
                priv->gfargrp[grp_idx].rstat = rstat;
                priv->gfargrp[grp_idx].tstat = tstat;
                rstat = tstat =0;
        }

        gfar_write(&regs->rqueue, rqueue);
        gfar_write(&regs->tqueue, tqueue);

        priv->rx_buffer_size = DEFAULT_RX_BUFFER_SIZE;

        /* Initializing some of the rx/tx queue level parameters */
        for (i = 0; i < priv->num_tx_queues; i++) {
                priv->tx_queue[i]->tx_ring_size = DEFAULT_TX_RING_SIZE;
                priv->tx_queue[i]->num_txbdfree = DEFAULT_TX_RING_SIZE;
                priv->tx_queue[i]->txcoalescing = DEFAULT_TX_COALESCE;
                priv->tx_queue[i]->txic = DEFAULT_TXIC;
        }

        for (i = 0; i < priv->num_rx_queues; i++) {
                priv->rx_queue[i]->rx_ring_size = DEFAULT_RX_RING_SIZE;
                priv->rx_queue[i]->rxcoalescing = DEFAULT_RX_COALESCE;
                priv->rx_queue[i]->rxic = DEFAULT_RXIC;
        }

        /* always enable rx filer */
        priv->rx_filer_enable = 1;
        /* Enable most messages by default */
        priv->msg_enable = (NETIF_MSG_IFUP << 1 ) - 1;
        /* use pritority h/w tx queue scheduling for single queue devices */
        if (priv->num_tx_queues == 1)
                priv->prio_sched_en = 1;

        /* Carrier starts down, phylib will bring it up */
        netif_carrier_off(dev);

        err = register_netdev(dev);

        if (err) {
                pr_err("%s: Cannot register net device, aborting\n", dev->name);
                goto register_fail;
        }

        device_init_wakeup(&dev->dev,
                           priv->device_flags &
                           FSL_GIANFAR_DEV_HAS_MAGIC_PACKET);

        /* fill out IRQ number and name fields */
        for (i = 0; i < priv->num_grps; i++) {
                struct gfar_priv_grp *grp = &priv->gfargrp[i];
                if (priv->device_flags & FSL_GIANFAR_DEV_HAS_MULTI_INTR) {
                        sprintf(gfar_irq(grp, TX)->name, "%s%s%c%s",
                                dev->name, "_g", '0' + i, "_tx");
                        sprintf(gfar_irq(grp, RX)->name, "%s%s%c%s",
                                dev->name, "_g", '0' + i, "_rx");
                        sprintf(gfar_irq(grp, ER)->name, "%s%s%c%s",
                                dev->name, "_g", '0' + i, "_er");
                } else
                        strcpy(gfar_irq(grp, TX)->name, dev->name);
        }

        /* Initialize the filer table */
        gfar_init_filer_table(priv);

        /* Create all the sysfs files */
        gfar_init_sysfs(dev);

        /* Print out the device info */
        netdev_info(dev, "mac: %pM\n", dev->dev_addr);

        /* Even more device info helps when determining which kernel
         * provided which set of benchmarks.
         */
        netdev_info(dev, "Running with NAPI enabled\n");
        for (i = 0; i < priv->num_rx_queues; i++)
                netdev_info(dev, "RX BD ring size for Q[%d]: %d\n",
                            i, priv->rx_queue[i]->rx_ring_size);
        for (i = 0; i < priv->num_tx_queues; i++)
                netdev_info(dev, "TX BD ring size for Q[%d]: %d\n",
                            i, priv->tx_queue[i]->tx_ring_size);

        return 0;

register_fail:
        unmap_group_regs(priv);
        free_tx_pointers(priv);
        free_rx_pointers(priv);
        if (priv->phy_node)
                of_node_put(priv->phy_node);
        if (priv->tbi_node)
                of_node_put(priv->tbi_node);
        free_gfar_dev(priv);
        return err;
}

static int gfar_remove(struct platform_device *ofdev)
{
        struct gfar_private *priv = dev_get_drvdata(&ofdev->dev);

        if (priv->phy_node)
                of_node_put(priv->phy_node);
        if (priv->tbi_node)
                of_node_put(priv->tbi_node);

        dev_set_drvdata(&ofdev->dev, NULL);

        unregister_netdev(priv->ndev);
        unmap_group_regs(priv);
        free_gfar_dev(priv);

        return 0;
}

#ifdef CONFIG_PM

static int gfar_suspend(struct device *dev)
{
        struct gfar_private *priv = dev_get_drvdata(dev);
        struct net_device *ndev = priv->ndev;
        struct gfar __iomem *regs = priv->gfargrp[0].regs;
        unsigned long flags;
        u32 tempval;

        int magic_packet = priv->wol_en &&
                           (priv->device_flags &
                            FSL_GIANFAR_DEV_HAS_MAGIC_PACKET);

        netif_device_detach(ndev);

        if (netif_running(ndev)) {

                local_irq_save(flags);
                lock_tx_qs(priv);
                lock_rx_qs(priv);

                gfar_halt_nodisable(ndev);

                /* Disable Tx, and Rx if wake-on-LAN is disabled. */
                tempval = gfar_read(&regs->maccfg1);

                tempval &= ~MACCFG1_TX_EN;

                if (!magic_packet)
                        tempval &= ~MACCFG1_RX_EN;

                gfar_write(&regs->maccfg1, tempval);

                unlock_rx_qs(priv);
                unlock_tx_qs(priv);
                local_irq_restore(flags);

                disable_napi(priv);

                if (magic_packet) {
                        /* Enable interrupt on Magic Packet */
                        gfar_write(&regs->imask, IMASK_MAG);

                        /* Enable Magic Packet mode */
                        tempval = gfar_read(&regs->maccfg2);
                        tempval |= MACCFG2_MPEN;
                        gfar_write(&regs->maccfg2, tempval);
                } else {
                        phy_stop(priv->phydev);
                }
        }

        return 0;
}

static int gfar_resume(struct device *dev)
{
        struct gfar_private *priv = dev_get_drvdata(dev);
        struct net_device *ndev = priv->ndev;
        struct gfar __iomem *regs = priv->gfargrp[0].regs;
        unsigned long flags;
        u32 tempval;
        int magic_packet = priv->wol_en &&
                           (priv->device_flags &
                            FSL_GIANFAR_DEV_HAS_MAGIC_PACKET);

        if (!netif_running(ndev)) {
                netif_device_attach(ndev);
                return 0;
        }

        if (!magic_packet && priv->phydev)
                phy_start(priv->phydev);

        /* Disable Magic Packet mode, in case something
         * else woke us up.
         */
        local_irq_save(flags);
        lock_tx_qs(priv);
        lock_rx_qs(priv);

        tempval = gfar_read(&regs->maccfg2);
        tempval &= ~MACCFG2_MPEN;
        gfar_write(&regs->maccfg2, tempval);

        gfar_start(ndev);

        unlock_rx_qs(priv);
        unlock_tx_qs(priv);
        local_irq_restore(flags);

        netif_device_attach(ndev);

        enable_napi(priv);

        return 0;
}

static int gfar_restore(struct device *dev)
{
        struct gfar_private *priv = dev_get_drvdata(dev);
        struct net_device *ndev = priv->ndev;

        if (!netif_running(ndev)) {
                netif_device_attach(ndev);

                return 0;
        }

        if (gfar_init_bds(ndev)) {
                free_skb_resources(priv);
                return -ENOMEM;
        }

        init_registers(ndev);
        gfar_set_mac_address(ndev);
        gfar_init_mac(ndev);
        gfar_start(ndev);

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

        if (priv->phydev)
                phy_start(priv->phydev);

        netif_device_attach(ndev);
        enable_napi(priv);

        return 0;
}

static struct dev_pm_ops gfar_pm_ops = {
        .suspend = gfar_suspend,
        .resume = gfar_resume,
        .freeze = gfar_suspend,
        .thaw = gfar_resume,
        .restore = gfar_restore,
};

#define GFAR_PM_OPS (&gfar_pm_ops)

#else

#define GFAR_PM_OPS NULL

#endif

/* Reads the controller's registers to determine what interface
 * connects it to the PHY.
 */
static phy_interface_t gfar_get_interface(struct net_device *dev)
{
        struct gfar_private *priv = netdev_priv(dev);
        struct gfar __iomem *regs = priv->gfargrp[0].regs;
        u32 ecntrl;

        ecntrl = gfar_read(&regs->ecntrl);

        if (ecntrl & ECNTRL_SGMII_MODE)
                return PHY_INTERFACE_MODE_SGMII;

        if (ecntrl & ECNTRL_TBI_MODE) {
                if (ecntrl & ECNTRL_REDUCED_MODE)
                        return PHY_INTERFACE_MODE_RTBI;
                else
                        return PHY_INTERFACE_MODE_TBI;
        }

        if (ecntrl & ECNTRL_REDUCED_MODE) {
                if (ecntrl & ECNTRL_REDUCED_MII_MODE) {
                        return PHY_INTERFACE_MODE_RMII;
                }
                else {
                        phy_interface_t interface = priv->interface;

                        /* This isn't autodetected right now, so it must
                         * be set by the device tree or platform code.
                         */
                        if (interface == PHY_INTERFACE_MODE_RGMII_ID)
                                return PHY_INTERFACE_MODE_RGMII_ID;

                        return PHY_INTERFACE_MODE_RGMII;
                }
        }

        if (priv->device_flags & FSL_GIANFAR_DEV_HAS_GIGABIT)
                return PHY_INTERFACE_MODE_GMII;

        return PHY_INTERFACE_MODE_MII;
}


/* Initializes driver's PHY state, and attaches to the PHY.
 * Returns 0 on success.
 */
static int init_phy(struct net_device *dev)
{
        struct gfar_private *priv = netdev_priv(dev);
        uint gigabit_support =
                priv->device_flags & FSL_GIANFAR_DEV_HAS_GIGABIT ?
                SUPPORTED_1000baseT_Full : 0;
        phy_interface_t interface;

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

        interface = gfar_get_interface(dev);

        priv->phydev = of_phy_connect(dev, priv->phy_node, &adjust_link, 0,
                                      interface);
        if (!priv->phydev)
                priv->phydev = of_phy_connect_fixed_link(dev, &adjust_link,
                                                         interface);
        if (!priv->phydev) {
                dev_err(&dev->dev, "could not attach to PHY\n");
                return -ENODEV;
        }

        if (interface == PHY_INTERFACE_MODE_SGMII)
                gfar_configure_serdes(dev);

        /* Remove any features not supported by the controller */
        priv->phydev->supported &= (GFAR_SUPPORTED | gigabit_support);
        priv->phydev->advertising = priv->phydev->supported;

        return 0;
}

/* Initialize TBI PHY interface for communicating with the
 * SERDES lynx PHY on the chip.  We communicate with this PHY
 * through the MDIO bus on each controller, treating it as a
 * "normal" PHY at the address found in the TBIPA register.  We assume
 * that the TBIPA register is valid.  Either the MDIO bus code will set
 * it to a value that doesn't conflict with other PHYs on the bus, or the
 * value doesn't matter, as there are no other PHYs on the bus.
 */
static void gfar_configure_serdes(struct net_device *dev)
{
        struct gfar_private *priv = netdev_priv(dev);
        struct phy_device *tbiphy;

        if (!priv->tbi_node) {
                dev_warn(&dev->dev, "error: SGMII mode requires that the "
                                    "device tree specify a tbi-handle\n");
                return;
        }

        tbiphy = of_phy_find_device(priv->tbi_node);
        if (!tbiphy) {
                dev_err(&dev->dev, "error: Could not get TBI device\n");
                return;
        }

        /* If the link is already up, we must already be ok, and don't need to
         * configure and reset the TBI<->SerDes link.  Maybe U-Boot configured
         * everything for us?  Resetting it takes the link down and requires
         * several seconds for it to come back.
         */
        if (phy_read(tbiphy, MII_BMSR) & BMSR_LSTATUS)
                return;

        /* Single clk mode, mii mode off(for serdes communication) */
        phy_write(tbiphy, MII_TBICON, TBICON_CLK_SELECT);

        phy_write(tbiphy, MII_ADVERTISE,
                  ADVERTISE_1000XFULL | ADVERTISE_1000XPAUSE |
                  ADVERTISE_1000XPSE_ASYM);

        phy_write(tbiphy, MII_BMCR,
                  BMCR_ANENABLE | BMCR_ANRESTART | BMCR_FULLDPLX |
                  BMCR_SPEED1000);
}

static void init_registers(struct net_device *dev)
{
        struct gfar_private *priv = netdev_priv(dev);
        struct gfar __iomem *regs = NULL;
        int i;

        for (i = 0; i < priv->num_grps; i++) {
                regs = priv->gfargrp[i].regs;
                /* Clear IEVENT */
                gfar_write(&regs->ievent, IEVENT_INIT_CLEAR);

                /* Initialize IMASK */
                gfar_write(&regs->imask, IMASK_INIT_CLEAR);
        }

        regs = priv->gfargrp[0].regs;
        /* Init hash registers to zero */
        gfar_write(&regs->igaddr0, 0);
        gfar_write(&regs->igaddr1, 0);
        gfar_write(&regs->igaddr2, 0);
        gfar_write(&regs->igaddr3, 0);
        gfar_write(&regs->igaddr4, 0);
        gfar_write(&regs->igaddr5, 0);
        gfar_write(&regs->igaddr6, 0);
        gfar_write(&regs->igaddr7, 0);

        gfar_write(&regs->gaddr0, 0);
        gfar_write(&regs->gaddr1, 0);
        gfar_write(&regs->gaddr2, 0);
        gfar_write(&regs->gaddr3, 0);
        gfar_write(&regs->gaddr4, 0);
        gfar_write(&regs->gaddr5, 0);
        gfar_write(&regs->gaddr6, 0);
        gfar_write(&regs->gaddr7, 0);

        /* Zero out the rmon mib registers if it has them */
        if (priv->device_flags & FSL_GIANFAR_DEV_HAS_RMON) {
                memset_io(&(regs->rmon), 0, sizeof (struct rmon_mib));

                /* Mask off the CAM interrupts */
                gfar_write(&regs->rmon.cam1, 0xffffffff);
                gfar_write(&regs->rmon.cam2, 0xffffffff);
        }

        /* Initialize the max receive buffer length */
        gfar_write(&regs->mrblr, priv->rx_buffer_size);

        /* Initialize the Minimum Frame Length Register */
        gfar_write(&regs->minflr, MINFLR_INIT_SETTINGS);
}

static int __gfar_is_rx_idle(struct gfar_private *priv)
{
        u32 res;

        /* Normaly TSEC should not hang on GRS commands, so we should
         * actually wait for IEVENT_GRSC flag.
         */
        if (likely(!gfar_has_errata(priv, GFAR_ERRATA_A002)))
                return 0;

        /* Read the eTSEC register at offset 0xD1C. If bits 7-14 are
         * the same as bits 23-30, the eTSEC Rx is assumed to be idle
         * and the Rx can be safely reset.
         */
        res = gfar_read((void __iomem *)priv->gfargrp[0].regs + 0xd1c);
        res &= 0x7f807f80;
        if ((res & 0xffff) == (res >> 16))
                return 1;

        return 0;
}

/* Halt the receive and transmit queues */
static void gfar_halt_nodisable(struct net_device *dev)
{
        struct gfar_private *priv = netdev_priv(dev);
        struct gfar __iomem *regs = NULL;
        u32 tempval;
        int i;

        for (i = 0; i < priv->num_grps; i++) {
                regs = priv->gfargrp[i].regs;
                /* Mask all interrupts */
                gfar_write(&regs->imask, IMASK_INIT_CLEAR);

                /* Clear all interrupts */
                gfar_write(&regs->ievent, IEVENT_INIT_CLEAR);
        }

        regs = priv->gfargrp[0].regs;
        /* Stop the DMA, and wait for it to stop */
        tempval = gfar_read(&regs->dmactrl);
        if ((tempval & (DMACTRL_GRS | DMACTRL_GTS)) !=
            (DMACTRL_GRS | DMACTRL_GTS)) {
                int ret;

                tempval |= (DMACTRL_GRS | DMACTRL_GTS);
                gfar_write(&regs->dmactrl, tempval);

                do {
                        ret = spin_event_timeout(((gfar_read(&regs->ievent) &
                                 (IEVENT_GRSC | IEVENT_GTSC)) ==
                                 (IEVENT_GRSC | IEVENT_GTSC)), 1000000, 0);
                        if (!ret && !(gfar_read(&regs->ievent) & IEVENT_GRSC))
                                ret = __gfar_is_rx_idle(priv);
                } while (!ret);
        }
}

/* Halt the receive and transmit queues */
void gfar_halt(struct net_device *dev)
{
        struct gfar_private *priv = netdev_priv(dev);
        struct gfar __iomem *regs = priv->gfargrp[0].regs;
        u32 tempval;

        gfar_halt_nodisable(dev);

        /* Disable Rx and Tx */
        tempval = gfar_read(&regs->maccfg1);
        tempval &= ~(MACCFG1_RX_EN | MACCFG1_TX_EN);
        gfar_write(&regs->maccfg1, tempval);
}

static void free_grp_irqs(struct gfar_priv_grp *grp)
{
        free_irq(gfar_irq(grp, TX)->irq, grp);
        free_irq(gfar_irq(grp, RX)->irq, grp);
        free_irq(gfar_irq(grp, ER)->irq, grp);
}

void stop_gfar(struct net_device *dev)
{
        struct gfar_private *priv = netdev_priv(dev);
        unsigned long flags;
        int i;

        phy_stop(priv->phydev);


        /* Lock it down */
        local_irq_save(flags);
        lock_tx_qs(priv);
        lock_rx_qs(priv);

        gfar_halt(dev);

        unlock_rx_qs(priv);
        unlock_tx_qs(priv);
        local_irq_restore(flags);

        /* Free the IRQs */
        if (priv->device_flags & FSL_GIANFAR_DEV_HAS_MULTI_INTR) {
                for (i = 0; i < priv->num_grps; i++)
                        free_grp_irqs(&priv->gfargrp[i]);
        } else {
                for (i = 0; i < priv->num_grps; i++)
                        free_irq(gfar_irq(&priv->gfargrp[i], TX)->irq,
                                 &priv->gfargrp[i]);
        }

        free_skb_resources(priv);
}

static void free_skb_tx_queue(struct gfar_priv_tx_q *tx_queue)
{
        struct txbd8 *txbdp;
        struct gfar_private *priv = netdev_priv(tx_queue->dev);
        int i, j;

        txbdp = tx_queue->tx_bd_base;

        for (i = 0; i < tx_queue->tx_ring_size; i++) {
                if (!tx_queue->tx_skbuff[i])
                        continue;

                dma_unmap_single(priv->dev, txbdp->bufPtr,
                                 txbdp->length, DMA_TO_DEVICE);
                txbdp->lstatus = 0;
                for (j = 0; j < skb_shinfo(tx_queue->tx_skbuff[i])->nr_frags;
                     j++) {
                        txbdp++;
                        dma_unmap_page(priv->dev, txbdp->bufPtr,
                                       txbdp->length, DMA_TO_DEVICE);
                }
                txbdp++;
                dev_kfree_skb_any(tx_queue->tx_skbuff[i]);
                tx_queue->tx_skbuff[i] = NULL;
        }
        kfree(tx_queue->tx_skbuff);
        tx_queue->tx_skbuff = NULL;
}

static void free_skb_rx_queue(struct gfar_priv_rx_q *rx_queue)
{
        struct rxbd8 *rxbdp;
        struct gfar_private *priv = netdev_priv(rx_queue->dev);
        int i;

        rxbdp = rx_queue->rx_bd_base;

        for (i = 0; i < rx_queue->rx_ring_size; i++) {
                if (rx_queue->rx_skbuff[i]) {
                        dma_unmap_single(priv->dev, rxbdp->bufPtr,
                                         priv->rx_buffer_size,
                                         DMA_FROM_DEVICE);
                        dev_kfree_skb_any(rx_queue->rx_skbuff[i]);
                        rx_queue->rx_skbuff[i] = NULL;
                }
                rxbdp->lstatus = 0;
                rxbdp->bufPtr = 0;
                rxbdp++;
        }
        kfree(rx_queue->rx_skbuff);
        rx_queue->rx_skbuff = NULL;
}

/* If there are any tx skbs or rx skbs still around, free them.
 * Then free tx_skbuff and rx_skbuff
 */
static void free_skb_resources(struct gfar_private *priv)
{
        struct gfar_priv_tx_q *tx_queue = NULL;
        struct gfar_priv_rx_q *rx_queue = NULL;
        int i;

        /* Go through all the buffer descriptors and free their data buffers */
        for (i = 0; i < priv->num_tx_queues; i++) {
                struct netdev_queue *txq;

                tx_queue = priv->tx_queue[i];
                txq = netdev_get_tx_queue(tx_queue->dev, tx_queue->qindex);
                if (tx_queue->tx_skbuff)
                        free_skb_tx_queue(tx_queue);
                netdev_tx_reset_queue(txq);
        }

        for (i = 0; i < priv->num_rx_queues; i++) {
                rx_queue = priv->rx_queue[i];
                if (rx_queue->rx_skbuff)
                        free_skb_rx_queue(rx_queue);
        }

        dma_free_coherent(priv->dev,
                          sizeof(struct txbd8) * priv->total_tx_ring_size +
                          sizeof(struct rxbd8) * priv->total_rx_ring_size,
                          priv->tx_queue[0]->tx_bd_base,
                          priv->tx_queue[0]->tx_bd_dma_base);
}

void gfar_start(struct net_device *dev)
{
        struct gfar_private *priv = netdev_priv(dev);
        struct gfar __iomem *regs = priv->gfargrp[0].regs;
        u32 tempval;
        int i = 0;

        /* Enable Rx and Tx in MACCFG1 */
        tempval = gfar_read(&regs->maccfg1);
        tempval |= (MACCFG1_RX_EN | MACCFG1_TX_EN);
        gfar_write(&regs->maccfg1, tempval);

        /* Initialize DMACTRL to have WWR and WOP */
        tempval = gfar_read(&regs->dmactrl);
        tempval |= DMACTRL_INIT_SETTINGS;
        gfar_write(&regs->dmactrl, tempval);

        /* Make sure we aren't stopped */
        tempval = gfar_read(&regs->dmactrl);
        tempval &= ~(DMACTRL_GRS | DMACTRL_GTS);
        gfar_write(&regs->dmactrl, tempval);

        for (i = 0; i < priv->num_grps; i++) {
                regs = priv->gfargrp[i].regs;
                /* Clear THLT/RHLT, so that the DMA starts polling now */
                gfar_write(&regs->tstat, priv->gfargrp[i].tstat);
                gfar_write(&regs->rstat, priv->gfargrp[i].rstat);
                /* Unmask the interrupts we look for */
                gfar_write(&regs->imask, IMASK_DEFAULT);
        }

        dev->trans_start = jiffies; /* prevent tx timeout */
}

static void gfar_configure_coalescing(struct gfar_private *priv,
                               unsigned long tx_mask, unsigned long rx_mask)
{
        struct gfar __iomem *regs = priv->gfargrp[0].regs;
        u32 __iomem *baddr;

        if (priv->mode == MQ_MG_MODE) {
                int i = 0;

                baddr = &regs->txic0;
                for_each_set_bit(i, &tx_mask, priv->num_tx_queues) {
                        gfar_write(baddr + i, 0);
                        if (likely(priv->tx_queue[i]->txcoalescing))
                                gfar_write(baddr + i, priv->tx_queue[i]->txic);
                }

                baddr = &regs->rxic0;
                for_each_set_bit(i, &rx_mask, priv->num_rx_queues) {
                        gfar_write(baddr + i, 0);
                        if (likely(priv->rx_queue[i]->rxcoalescing))
                                gfar_write(baddr + i, priv->rx_queue[i]->rxic);
                }
        } else {
                /* Backward compatible case -- even if we enable
                 * multiple queues, there's only single reg to program
                 */
                gfar_write(&regs->txic, 0);
                if (likely(priv->tx_queue[0]->txcoalescing))
                        gfar_write(&regs->txic, priv->tx_queue[0]->txic);

                gfar_write(&regs->rxic, 0);
                if (unlikely(priv->rx_queue[0]->rxcoalescing))
                        gfar_write(&regs->rxic, priv->rx_queue[0]->rxic);
        }
}

void gfar_configure_coalescing_all(struct gfar_private *priv)
{
        gfar_configure_coalescing(priv, 0xFF, 0xFF);
}

static int register_grp_irqs(struct gfar_priv_grp *grp)
{
        struct gfar_private *priv = grp->priv;
        struct net_device *dev = priv->ndev;
        int err;

        /* If the device has multiple interrupts, register for
         * them.  Otherwise, only register for the one
         */
        if (priv->device_flags & FSL_GIANFAR_DEV_HAS_MULTI_INTR) {
                /* Install our interrupt handlers for Error,
                 * Transmit, and Receive
                 */
                err = request_irq(gfar_irq(grp, ER)->irq, gfar_error, 0,
                                  gfar_irq(grp, ER)->name, grp);
                if (err < 0) {
                        netif_err(priv, intr, dev, "Can't get IRQ %d\n",
                                  gfar_irq(grp, ER)->irq);

                        goto err_irq_fail;
                }
                err = request_irq(gfar_irq(grp, TX)->irq, gfar_transmit, 0,
                                  gfar_irq(grp, TX)->name, grp);
                if (err < 0) {
                        netif_err(priv, intr, dev, "Can't get IRQ %d\n",
                                  gfar_irq(grp, TX)->irq);
                        goto tx_irq_fail;
                }
                err = request_irq(gfar_irq(grp, RX)->irq, gfar_receive, 0,
                                  gfar_irq(grp, RX)->name, grp);
                if (err < 0) {
                        netif_err(priv, intr, dev, "Can't get IRQ %d\n",
                                  gfar_irq(grp, RX)->irq);
                        goto rx_irq_fail;
                }
        } else {
                err = request_irq(gfar_irq(grp, TX)->irq, gfar_interrupt, 0,
                                  gfar_irq(grp, TX)->name, grp);
                if (err < 0) {
                        netif_err(priv, intr, dev, "Can't get IRQ %d\n",
                                  gfar_irq(grp, TX)->irq);
                        goto err_irq_fail;
                }
        }

        return 0;

rx_irq_fail:
        free_irq(gfar_irq(grp, TX)->irq, grp);
tx_irq_fail:
        free_irq(gfar_irq(grp, ER)->irq, grp);
err_irq_fail:
        return err;

}

/* Bring the controller up and running */
int startup_gfar(struct net_device *ndev)
{
        struct gfar_private *priv = netdev_priv(ndev);
        struct gfar __iomem *regs = NULL;
        int err, i, j;

        for (i = 0; i < priv->num_grps; i++) {
                regs= priv->gfargrp[i].regs;
                gfar_write(&regs->imask, IMASK_INIT_CLEAR);
        }

        regs= priv->gfargrp[0].regs;
        err = gfar_alloc_skb_resources(ndev);
        if (err)
                return err;

        gfar_init_mac(ndev);

        for (i = 0; i < priv->num_grps; i++) {
                err = register_grp_irqs(&priv->gfargrp[i]);
                if (err) {
                        for (j = 0; j < i; j++)
                                free_grp_irqs(&priv->gfargrp[j]);
                        goto irq_fail;
                }
        }

        /* Start the controller */
        gfar_start(ndev);

        phy_start(priv->phydev);

        gfar_configure_coalescing_all(priv);

        return 0;

irq_fail:
        free_skb_resources(priv);
        return err;
}

/* Called when something needs to use the ethernet device
 * Returns 0 for success.
 */
static int gfar_enet_open(struct net_device *dev)
{
        struct gfar_private *priv = netdev_priv(dev);
        int err;

        enable_napi(priv);

        /* Initialize a bunch of registers */
        init_registers(dev);

        gfar_set_mac_address(dev);

        err = init_phy(dev);

        if (err) {
                disable_napi(priv);
                return err;
        }

        err = startup_gfar(dev);
        if (err) {
                disable_napi(priv);
                return err;
        }

        netif_tx_start_all_queues(dev);

        device_set_wakeup_enable(&dev->dev, priv->wol_en);

        return err;
}

static inline struct txfcb *gfar_add_fcb(struct sk_buff *skb)
{
        struct txfcb *fcb = (struct txfcb *)skb_push(skb, GMAC_FCB_LEN);

        memset(fcb, 0, GMAC_FCB_LEN);

        return fcb;
}

static inline void gfar_tx_checksum(struct sk_buff *skb, struct txfcb *fcb,
                                    int fcb_length)
{
        /* If we're here, it's a IP packet with a TCP or UDP
         * payload.  We set it to checksum, using a pseudo-header
         * we provide
         */
        u8 flags = TXFCB_DEFAULT;

        /* Tell the controller what the protocol is
         * And provide the already calculated phcs
         */
        if (ip_hdr(skb)->protocol == IPPROTO_UDP) {
                flags |= TXFCB_UDP;
                fcb->phcs = udp_hdr(skb)->check;
        } else
                fcb->phcs = tcp_hdr(skb)->check;

        /* l3os is the distance between the start of the
         * frame (skb->data) and the start of the IP hdr.
         * l4os is the distance between the start of the
         * l3 hdr and the l4 hdr
         */
        fcb->l3os = (u16)(skb_network_offset(skb) - fcb_length);
        fcb->l4os = skb_network_header_len(skb);

        fcb->flags = flags;
}

void inline gfar_tx_vlan(struct sk_buff *skb, struct txfcb *fcb)
{
        fcb->flags |= TXFCB_VLN;
        fcb->vlctl = vlan_tx_tag_get(skb);
}

static inline struct txbd8 *skip_txbd(struct txbd8 *bdp, int stride,
                                      struct txbd8 *base, int ring_size)
{
        struct txbd8 *new_bd = bdp + stride;

        return (new_bd >= (base + ring_size)) ? (new_bd - ring_size) : new_bd;
}

static inline struct txbd8 *next_txbd(struct txbd8 *bdp, struct txbd8 *base,
                                      int ring_size)
{
        return skip_txbd(bdp, 1, base, ring_size);
}

/* This is called by the kernel when a frame is ready for transmission.
 * It is pointed to by the dev->hard_start_xmit function pointer
 */
static int gfar_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
        struct gfar_private *priv = netdev_priv(dev);
        struct gfar_priv_tx_q *tx_queue = NULL;
        struct netdev_queue *txq;
        struct gfar __iomem *regs = NULL;
        struct txfcb *fcb = NULL;
        struct txbd8 *txbdp, *txbdp_start, *base, *txbdp_tstamp = NULL;
        u32 lstatus;
        int i, rq = 0, do_tstamp = 0;
        u32 bufaddr;
        unsigned long flags;
        unsigned int nr_frags, nr_txbds, length, fcb_length = GMAC_FCB_LEN;

        /* TOE=1 frames larger than 2500 bytes may see excess delays
         * before start of transmission.
         */
        if (unlikely(gfar_has_errata(priv, GFAR_ERRATA_76) &&
                     skb->ip_summed == CHECKSUM_PARTIAL &&
                     skb->len > 2500)) {
                int ret;

                ret = skb_checksum_help(skb);
                if (ret)
                        return ret;
        }

        rq = skb->queue_mapping;
        tx_queue = priv->tx_queue[rq];
        txq = netdev_get_tx_queue(dev, rq);
        base = tx_queue->tx_bd_base;
        regs = tx_queue->grp->regs;

        /* check if time stamp should be generated */
        if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP &&
                     priv->hwts_tx_en)) {
                do_tstamp = 1;
                fcb_length = GMAC_FCB_LEN + GMAC_TXPAL_LEN;
        }

        /* make space for additional header when fcb is needed */
        if (((skb->ip_summed == CHECKSUM_PARTIAL) ||
             vlan_tx_tag_present(skb) ||
             unlikely(do_tstamp)) &&
            (skb_headroom(skb) < fcb_length)) {
                struct sk_buff *skb_new;

                skb_new = skb_realloc_headroom(skb, fcb_length);
                if (!skb_new) {
                        dev->stats.tx_errors++;
                        kfree_skb(skb);
                        return NETDEV_TX_OK;
                }

                if (skb->sk)
                        skb_set_owner_w(skb_new, skb->sk);
                consume_skb(skb);
                skb = skb_new;
        }

        /* total number of fragments in the SKB */
        nr_frags = skb_shinfo(skb)->nr_frags;

        /* calculate the required number of TxBDs for this skb */
        if (unlikely(do_tstamp))
                nr_txbds = nr_frags + 2;
        else
                nr_txbds = nr_frags + 1;

        /* check if there is space to queue this packet */
        if (nr_txbds > tx_queue->num_txbdfree) {
                /* no space, stop the queue */
                netif_tx_stop_queue(txq);
                dev->stats.tx_fifo_errors++;
                return NETDEV_TX_BUSY;
        }

        /* Update transmit stats */
        tx_queue->stats.tx_bytes += skb->len;
        tx_queue->stats.tx_packets++;

        txbdp = txbdp_start = tx_queue->cur_tx;
        lstatus = txbdp->lstatus;

        /* Time stamp insertion requires one additional TxBD */
        if (unlikely(do_tstamp))
                txbdp_tstamp = txbdp = next_txbd(txbdp, base,
                                                 tx_queue->tx_ring_size);

        if (nr_frags == 0) {
                if (unlikely(do_tstamp))
                        txbdp_tstamp->lstatus |= BD_LFLAG(TXBD_LAST |
                                                          TXBD_INTERRUPT);
                else
                        lstatus |= BD_LFLAG(TXBD_LAST | TXBD_INTERRUPT);
        } else {
                /* Place the fragment addresses and lengths into the TxBDs */
                for (i = 0; i < nr_frags; i++) {
                        /* Point at the next BD, wrapping as needed */
                        txbdp = next_txbd(txbdp, base, tx_queue->tx_ring_size);

                        length = skb_shinfo(skb)->frags[i].size;

                        lstatus = txbdp->lstatus | length |
                                  BD_LFLAG(TXBD_READY);

                        /* Handle the last BD specially */
                        if (i == nr_frags - 1)
                                lstatus |= BD_LFLAG(TXBD_LAST | TXBD_INTERRUPT);

                        bufaddr = skb_frag_dma_map(priv->dev,
                                                   &skb_shinfo(skb)->frags[i],
                                                   0,
                                                   length,
                                                   DMA_TO_DEVICE);

                        /* set the TxBD length and buffer pointer */
                        txbdp->bufPtr = bufaddr;
                        txbdp->lstatus = lstatus;
                }

                lstatus = txbdp_start->lstatus;
        }

        /* Add TxPAL between FCB and frame if required */
        if (unlikely(do_tstamp)) {
                skb_push(skb, GMAC_TXPAL_LEN);
                memset(skb->data, 0, GMAC_TXPAL_LEN);
        }

        /* Set up checksumming */
        if (CHECKSUM_PARTIAL == skb->ip_summed) {
                fcb = gfar_add_fcb(skb);
                /* as specified by errata */
                if (unlikely(gfar_has_errata(priv, GFAR_ERRATA_12) &&
                             ((unsigned long)fcb % 0x20) > 0x18)) {
                        __skb_pull(skb, GMAC_FCB_LEN);
                        skb_checksum_help(skb);
                } else {
                        lstatus |= BD_LFLAG(TXBD_TOE);
                        gfar_tx_checksum(skb, fcb, fcb_length);
                }
        }

        if (vlan_tx_tag_present(skb)) {
                if (unlikely(NULL == fcb)) {
                        fcb = gfar_add_fcb(skb);
                        lstatus |= BD_LFLAG(TXBD_TOE);
                }

                gfar_tx_vlan(skb, fcb);
        }

        /* Setup tx hardware time stamping if requested */
        if (unlikely(do_tstamp)) {
                skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
                if (fcb == NULL)
                        fcb = gfar_add_fcb(skb);
                fcb->ptp = 1;
                lstatus |= BD_LFLAG(TXBD_TOE);
        }

        txbdp_start->bufPtr = dma_map_single(priv->dev, skb->data,
                                             skb_headlen(skb), DMA_TO_DEVICE);

        /* If time stamping is requested one additional TxBD must be set up. The
         * first TxBD points to the FCB and must have a data length of
         * GMAC_FCB_LEN. The second TxBD points to the actual frame data with
         * the full frame length.
         */
        if (unlikely(do_tstamp)) {
                txbdp_tstamp->bufPtr = txbdp_start->bufPtr + fcb_length;
                txbdp_tstamp->lstatus |= BD_LFLAG(TXBD_READY) |
                                         (skb_headlen(skb) - fcb_length);
                lstatus |= BD_LFLAG(TXBD_CRC | TXBD_READY) | GMAC_FCB_LEN;
        } else {
                lstatus |= BD_LFLAG(TXBD_CRC | TXBD_READY) | skb_headlen(skb);
        }

        netdev_tx_sent_queue(txq, skb->len);

        /* We can work in parallel with gfar_clean_tx_ring(), except
         * when modifying num_txbdfree. Note that we didn't grab the lock
         * when we were reading the num_txbdfree and checking for available
         * space, that's because outside of this function it can only grow,
         * and once we've got needed space, it cannot suddenly disappear.
         *
         * The lock also protects us from gfar_error(), which can modify
         * regs->tstat and thus retrigger the transfers, which is why we
         * also must grab the lock before setting ready bit for the first
         * to be transmitted BD.
         */
        spin_lock_irqsave(&tx_queue->txlock, flags);

        /* The powerpc-specific eieio() is used, as wmb() has too strong
         * semantics (it requires synchronization between cacheable and
         * uncacheable mappings, which eieio doesn't provide and which we
         * don't need), thus requiring a more expensive sync instruction.  At
         * some point, the set of architecture-independent barrier functions
         * should be expanded to include weaker barriers.
         */
        eieio();

        txbdp_start->lstatus = lstatus;

        eieio(); /* force lstatus write before tx_skbuff */

        tx_queue->tx_skbuff[tx_queue->skb_curtx] = skb;

        /* Update the current skb pointer to the next entry we will use
         * (wrapping if necessary)
         */
        tx_queue->skb_curtx = (tx_queue->skb_curtx + 1) &
                              TX_RING_MOD_MASK(tx_queue->tx_ring_size);

        tx_queue->cur_tx = next_txbd(txbdp, base, tx_queue->tx_ring_size);

        /* reduce TxBD free count */
        tx_queue->num_txbdfree -= (nr_txbds);

        /* If the next BD still needs to be cleaned up, then the bds
         * are full.  We need to tell the kernel to stop sending us stuff.
         */
        if (!tx_queue->num_txbdfree) {
                netif_tx_stop_queue(txq);

                dev->stats.tx_fifo_errors++;
        }

        /* Tell the DMA to go go go */
        gfar_write(&regs->tstat, TSTAT_CLEAR_THALT >> tx_queue->qindex);

        /* Unlock priv */
        spin_unlock_irqrestore(&tx_queue->txlock, flags);

        return NETDEV_TX_OK;
}

/* Stops the kernel queue, and halts the controller */
static int gfar_close(struct net_device *dev)
{
        struct gfar_private *priv = netdev_priv(dev);

        disable_napi(priv);

        cancel_work_sync(&priv->reset_task);
        stop_gfar(dev);

        /* Disconnect from the PHY */
        phy_disconnect(priv->phydev);
        priv->phydev = NULL;

        netif_tx_stop_all_queues(dev);

        return 0;
}

/* Changes the mac address if the controller is not running. */
static int gfar_set_mac_address(struct net_device *dev)
{
        gfar_set_mac_for_addr(dev, 0, dev->dev_addr);

        return 0;
}

/* Check if rx parser should be activated */
void gfar_check_rx_parser_mode(struct gfar_private *priv)
{
        struct gfar __iomem *regs;
        u32 tempval;

        regs = priv->gfargrp[0].regs;

        tempval = gfar_read(&regs->rctrl);
        /* If parse is no longer required, then disable parser */
        if (tempval & RCTRL_REQ_PARSER) {
                tempval |= RCTRL_PRSDEP_INIT;
                priv->uses_rxfcb = 1;
        } else {
                tempval &= ~RCTRL_PRSDEP_INIT;
                priv->uses_rxfcb = 0;
        }
        gfar_write(&regs->rctrl, tempval);
}

/* Enables and disables VLAN insertion/extraction */
void gfar_vlan_mode(struct net_device *dev, netdev_features_t features)
{
        struct gfar_private *priv = netdev_priv(dev);
        struct gfar __iomem *regs = NULL;
        unsigned long flags;
        u32 tempval;

        regs = priv->gfargrp[0].regs;
        local_irq_save(flags);
        lock_rx_qs(priv);

        if (features & NETIF_F_HW_VLAN_CTAG_TX) {
                /* Enable VLAN tag insertion */
                tempval = gfar_read(&regs->tctrl);
                tempval |= TCTRL_VLINS;
                gfar_write(&regs->tctrl, tempval);
        } else {
                /* Disable VLAN tag insertion */
                tempval = gfar_read(&regs->tctrl);
                tempval &= ~TCTRL_VLINS;
                gfar_write(&regs->tctrl, tempval);
        }

        if (features & NETIF_F_HW_VLAN_CTAG_RX) {
                /* Enable VLAN tag extraction */
                tempval = gfar_read(&regs->rctrl);
                tempval |= (RCTRL_VLEX | RCTRL_PRSDEP_INIT);
                gfar_write(&regs->rctrl, tempval);
                priv->uses_rxfcb = 1;
        } else {
                /* Disable VLAN tag extraction */
                tempval = gfar_read(&regs->rctrl);
                tempval &= ~RCTRL_VLEX;
                gfar_write(&regs->rctrl, tempval);

                gfar_check_rx_parser_mode(priv);
        }

        gfar_change_mtu(dev, dev->mtu);

        unlock_rx_qs(priv);
        local_irq_restore(flags);
}

static int gfar_change_mtu(struct net_device *dev, int new_mtu)
{
        int tempsize, tempval;
        struct gfar_private *priv = netdev_priv(dev);
        struct gfar __iomem *regs = priv->gfargrp[0].regs;
        int oldsize = priv->rx_buffer_size;
        int frame_size = new_mtu + ETH_HLEN;

        if ((frame_size < 64) || (frame_size > JUMBO_FRAME_SIZE)) {
                netif_err(priv, drv, dev, "Invalid MTU setting\n");
                return -EINVAL;
        }

        if (priv->uses_rxfcb)
                frame_size += GMAC_FCB_LEN;

        frame_size += priv->padding;

        tempsize = (frame_size & ~(INCREMENTAL_BUFFER_SIZE - 1)) +
                   INCREMENTAL_BUFFER_SIZE;

        /* Only stop and start the controller if it isn't already
         * stopped, and we changed something
         */
        if ((oldsize != tempsize) && (dev->flags & IFF_UP))
                stop_gfar(dev);

        priv->rx_buffer_size = tempsize;

        dev->mtu = new_mtu;

        gfar_write(&regs->mrblr, priv->rx_buffer_size);
        gfar_write(&regs->maxfrm, priv->rx_buffer_size);

        /* If the mtu is larger than the max size for standard
         * ethernet frames (ie, a jumbo frame), then set maccfg2
         * to allow huge frames, and to check the length
         */
        tempval = gfar_read(&regs->maccfg2);

        if (priv->rx_buffer_size > DEFAULT_RX_BUFFER_SIZE ||
            gfar_has_errata(priv, GFAR_ERRATA_74))
                tempval |= (MACCFG2_HUGEFRAME | MACCFG2_LENGTHCHECK);
        else
                tempval &= ~(MACCFG2_HUGEFRAME | MACCFG2_LENGTHCHECK);

        gfar_write(&regs->maccfg2, tempval);

        if ((oldsize != tempsize) && (dev->flags & IFF_UP))
                startup_gfar(dev);

        return 0;
}

/* gfar_reset_task gets scheduled when a packet has not been
 * transmitted after a set amount of time.
 * For now, assume that clearing out all the structures, and
 * starting over will fix the problem.
 */
static void gfar_reset_task(struct work_struct *work)
{
        struct gfar_private *priv = container_of(work, struct gfar_private,
                                                 reset_task);
        struct net_device *dev = priv->ndev;

        if (dev->flags & IFF_UP) {
                netif_tx_stop_all_queues(dev);
                stop_gfar(dev);
                startup_gfar(dev);
                netif_tx_start_all_queues(dev);
        }

        netif_tx_schedule_all(dev);
}

static void gfar_timeout(struct net_device *dev)
{
        struct gfar_private *priv = netdev_priv(dev);

        dev->stats.tx_errors++;
        schedule_work(&priv->reset_task);
}

static void gfar_align_skb(struct sk_buff *skb)
{
        /* We need the data buffer to be aligned properly.  We will reserve
         * as many bytes as needed to align the data properly
         */
        skb_reserve(skb, RXBUF_ALIGNMENT -
                    (((unsigned long) skb->data) & (RXBUF_ALIGNMENT - 1)));
}

/* Interrupt Handler for Transmit complete */
static void gfar_clean_tx_ring(struct gfar_priv_tx_q *tx_queue)
{
        struct net_device *dev = tx_queue->dev;
        struct netdev_queue *txq;
        struct gfar_private *priv = netdev_priv(dev);
        struct txbd8 *bdp, *next = NULL;
        struct txbd8 *lbdp = NULL;
        struct txbd8 *base = tx_queue->tx_bd_base;
        struct sk_buff *skb;
        int skb_dirtytx;
        int tx_ring_size = tx_queue->tx_ring_size;
        int frags = 0, nr_txbds = 0;
        int i;
        int howmany = 0;
        int tqi = tx_queue->qindex;
        unsigned int bytes_sent = 0;
        u32 lstatus;
        size_t buflen;

        txq = netdev_get_tx_queue(dev, tqi);
        bdp = tx_queue->dirty_tx;
        skb_dirtytx = tx_queue->skb_dirtytx;

        while ((skb = tx_queue->tx_skbuff[skb_dirtytx])) {
                unsigned long flags;

                frags = skb_shinfo(skb)->nr_frags;

                /* When time stamping, one additional TxBD must be freed.
                 * Also, we need to dma_unmap_single() the TxPAL.
                 */
                if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS))
                        nr_txbds = frags + 2;
                else
                        nr_txbds = frags + 1;

                lbdp = skip_txbd(bdp, nr_txbds - 1, base, tx_ring_size);

                lstatus = lbdp->lstatus;

                /* Only clean completed frames */
                if ((lstatus & BD_LFLAG(TXBD_READY)) &&
                    (lstatus & BD_LENGTH_MASK))
                        break;

                if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS)) {
                        next = next_txbd(bdp, base, tx_ring_size);
                        buflen = next->length + GMAC_FCB_LEN + GMAC_TXPAL_LEN;
                } else
                        buflen = bdp->length;

                dma_unmap_single(priv->dev, bdp->bufPtr,
                                 buflen, DMA_TO_DEVICE);

                if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS)) {
                        struct skb_shared_hwtstamps shhwtstamps;
                        u64 *ns = (u64*) (((u32)skb->data + 0x10) & ~0x7);

                        memset(&shhwtstamps, 0, sizeof(shhwtstamps));
                        shhwtstamps.hwtstamp = ns_to_ktime(*ns);
                        skb_pull(skb, GMAC_FCB_LEN + GMAC_TXPAL_LEN);
                        skb_tstamp_tx(skb, &shhwtstamps);
                        bdp->lstatus &= BD_LFLAG(TXBD_WRAP);
                        bdp = next;
                }

                bdp->lstatus &= BD_LFLAG(TXBD_WRAP);
                bdp = next_txbd(bdp, base, tx_ring_size);

                for (i = 0; i < frags; i++) {
                        dma_unmap_page(priv->dev, bdp->bufPtr,
                                       bdp->length, DMA_TO_DEVICE);
                        bdp->lstatus &= BD_LFLAG(TXBD_WRAP);
                        bdp = next_txbd(bdp, base, tx_ring_size);
                }

                bytes_sent += skb->len;

                dev_kfree_skb_any(skb);

                tx_queue->tx_skbuff[skb_dirtytx] = NULL;

                skb_dirtytx = (skb_dirtytx + 1) &
                              TX_RING_MOD_MASK(tx_ring_size);

                howmany++;
                spin_lock_irqsave(&tx_queue->txlock, flags);
                tx_queue->num_txbdfree += nr_txbds;
                spin_unlock_irqrestore(&tx_queue->txlock, flags);
        }

        /* If we freed a buffer, we can restart transmission, if necessary */
        if (netif_tx_queue_stopped(txq) && tx_queue->num_txbdfree)
                netif_wake_subqueue(dev, tqi);

        /* Update dirty indicators */
        tx_queue->skb_dirtytx = skb_dirtytx;
        tx_queue->dirty_tx = bdp;

        netdev_tx_completed_queue(txq, howmany, bytes_sent);
}

static void gfar_schedule_cleanup(struct gfar_priv_grp *gfargrp)
{
        unsigned long flags;

        spin_lock_irqsave(&gfargrp->grplock, flags);
        if (napi_schedule_prep(&gfargrp->napi)) {
                gfar_write(&gfargrp->regs->imask, IMASK_RTX_DISABLED);
                __napi_schedule(&gfargrp->napi);
        } else {
                /* Clear IEVENT, so interrupts aren't called again
                 * because of the packets that have already arrived.
                 */
                gfar_write(&gfargrp->regs->ievent, IEVENT_RTX_MASK);
        }
        spin_unlock_irqrestore(&gfargrp->grplock, flags);

}

/* Interrupt Handler for Transmit complete */
static irqreturn_t gfar_transmit(int irq, void *grp_id)
{
        gfar_schedule_cleanup((struct gfar_priv_grp *)grp_id);
        return IRQ_HANDLED;
}

static void gfar_new_rxbdp(struct gfar_priv_rx_q *rx_queue, struct rxbd8 *bdp,
                           struct sk_buff *skb)
{
        struct net_device *dev = rx_queue->dev;
        struct gfar_private *priv = netdev_priv(dev);
        dma_addr_t buf;

        buf = dma_map_single(priv->dev, skb->data,
                             priv->rx_buffer_size, DMA_FROM_DEVICE);
        gfar_init_rxbdp(rx_queue, bdp, buf);
}

static struct sk_buff *gfar_alloc_skb(struct net_device *dev)
{
        struct gfar_private *priv = netdev_priv(dev);
        struct sk_buff *skb;

        skb = netdev_alloc_skb(dev, priv->rx_buffer_size + RXBUF_ALIGNMENT);
        if (!skb)
                return NULL;

        gfar_align_skb(skb);

        return skb;
}

struct sk_buff *gfar_new_skb(struct net_device *dev)
{
        return gfar_alloc_skb(dev);
}

static inline void count_errors(unsigned short status, struct net_device *dev)
{
        struct gfar_private *priv = netdev_priv(dev);
        struct net_device_stats *stats = &dev->stats;
        struct gfar_extra_stats *estats = &priv->extra_stats;

        /* If the packet was truncated, none of the other errors matter */
        if (status & RXBD_TRUNCATED) {
                stats->rx_length_errors++;

                atomic64_inc(&estats->rx_trunc);

                return;
        }
        /* Count the errors, if there were any */
        if (status & (RXBD_LARGE | RXBD_SHORT)) {
                stats->rx_length_errors++;

                if (status & RXBD_LARGE)
                        atomic64_inc(&estats->rx_large);
                else
                        atomic64_inc(&estats->rx_short);
        }
        if (status & RXBD_NONOCTET) {
                stats->rx_frame_errors++;
                atomic64_inc(&estats->rx_nonoctet);
        }
        if (status & RXBD_CRCERR) {
                atomic64_inc(&estats->rx_crcerr);
                stats->rx_crc_errors++;
        }
        if (status & RXBD_OVERRUN) {
                atomic64_inc(&estats->rx_overrun);
                stats->rx_crc_errors++;
        }
}

irqreturn_t gfar_receive(int irq, void *grp_id)
{
        gfar_schedule_cleanup((struct gfar_priv_grp *)grp_id);
        return IRQ_HANDLED;
}

static inline void gfar_rx_checksum(struct sk_buff *skb, struct rxfcb *fcb)
{
        /* If valid headers were found, and valid sums
         * were verified, then we tell the kernel that no
         * checksumming is necessary.  Otherwise, it is [FIXME]
         */
        if ((fcb->flags & RXFCB_CSUM_MASK) == (RXFCB_CIP | RXFCB_CTU))
                skb->ip_summed = CHECKSUM_UNNECESSARY;
        else
                skb_checksum_none_assert(skb);
}


/* gfar_process_frame() -- handle one incoming packet if skb isn't NULL. */
static void gfar_process_frame(struct net_device *dev, struct sk_buff *skb,
                               int amount_pull, struct napi_struct *napi)
{
        struct gfar_private *priv = netdev_priv(dev);
        struct rxfcb *fcb = NULL;

        /* fcb is at the beginning if exists */
        fcb = (struct rxfcb *)skb->data;

        /* Remove the FCB from the skb
         * Remove the padded bytes, if there are any
         */
        if (amount_pull) {
                skb_record_rx_queue(skb, fcb->rq);
                skb_pull(skb, amount_pull);
        }

        /* Get receive timestamp from the skb */
        if (priv->hwts_rx_en) {
                struct skb_shared_hwtstamps *shhwtstamps = skb_hwtstamps(skb);
                u64 *ns = (u64 *) skb->data;

                memset(shhwtstamps, 0, sizeof(*shhwtstamps));
                shhwtstamps->hwtstamp = ns_to_ktime(*ns);
        }

        if (priv->padding)
                skb_pull(skb, priv->padding);

        if (dev->features & NETIF_F_RXCSUM)
                gfar_rx_checksum(skb, fcb);

        /* Tell the skb what kind of packet this is */
        skb->protocol = eth_type_trans(skb, dev);

        /* There's need to check for NETIF_F_HW_VLAN_CTAG_RX here.
         * Even if vlan rx accel is disabled, on some chips
         * RXFCB_VLN is pseudo randomly set.
         */
        if (dev->features & NETIF_F_HW_VLAN_CTAG_RX &&
            fcb->flags & RXFCB_VLN)
                __vlan_hwaccel_put_tag(skb, fcb->vlctl);

        /* Send the packet up the stack */
        napi_gro_receive(napi, skb);

}

/* gfar_clean_rx_ring() -- Processes each frame in the rx ring
 * until the budget/quota has been reached. Returns the number
 * of frames handled
 */
int gfar_clean_rx_ring(struct gfar_priv_rx_q *rx_queue, int rx_work_limit)
{
        struct net_device *dev = rx_queue->dev;
        struct rxbd8 *bdp, *base;
        struct sk_buff *skb;
        int pkt_len;
        int amount_pull;
        int howmany = 0;
        struct gfar_private *priv = netdev_priv(dev);

        /* Get the first full descriptor */
        bdp = rx_queue->cur_rx;
        base = rx_queue->rx_bd_base;

        amount_pull = priv->uses_rxfcb ? GMAC_FCB_LEN : 0;

        while (!((bdp->status & RXBD_EMPTY) || (--rx_work_limit < 0))) {
                struct sk_buff *newskb;

                rmb();

                /* Add another skb for the future */
                newskb = gfar_new_skb(dev);

                skb = rx_queue->rx_skbuff[rx_queue->skb_currx];

                dma_unmap_single(priv->dev, bdp->bufPtr,
                                 priv->rx_buffer_size, DMA_FROM_DEVICE);

                if (unlikely(!(bdp->status & RXBD_ERR) &&
                             bdp->length > priv->rx_buffer_size))
                        bdp->status = RXBD_LARGE;

                /* We drop the frame if we failed to allocate a new buffer */
                if (unlikely(!newskb || !(bdp->status & RXBD_LAST) ||
                             bdp->status & RXBD_ERR)) {
                        count_errors(bdp->status, dev);

                        if (unlikely(!newskb))
                                newskb = skb;
                        else if (skb)
                                dev_kfree_skb(skb);
                } else {
                        /* Increment the number of packets */
                        rx_queue->stats.rx_packets++;
                        howmany++;

                        if (likely(skb)) {
                                pkt_len = bdp->length - ETH_FCS_LEN;
                                /* Remove the FCS from the packet length */
                                skb_put(skb, pkt_len);
                                rx_queue->stats.rx_bytes += pkt_len;
                                skb_record_rx_queue(skb, rx_queue->qindex);
                                gfar_process_frame(dev, skb, amount_pull,
                                                   &rx_queue->grp->napi);

                        } else {
                                netif_warn(priv, rx_err, dev, "Missing skb!\n");
                                rx_queue->stats.rx_dropped++;
                                atomic64_inc(&priv->extra_stats.rx_skbmissing);
                        }

                }

                rx_queue->rx_skbuff[rx_queue->skb_currx] = newskb;

                /* Setup the new bdp */
                gfar_new_rxbdp(rx_queue, bdp, newskb);

                /* Update to the next pointer */
                bdp = next_bd(bdp, base, rx_queue->rx_ring_size);

                /* update to point at the next skb */
                rx_queue->skb_currx = (rx_queue->skb_currx + 1) &
                                      RX_RING_MOD_MASK(rx_queue->rx_ring_size);
        }

        /* Update the current rxbd pointer to be the next one */
        rx_queue->cur_rx = bdp;

        return howmany;
}

static int gfar_poll(struct napi_struct *napi, int budget)
{
        struct gfar_priv_grp *gfargrp =
                container_of(napi, struct gfar_priv_grp, napi);
        struct gfar_private *priv = gfargrp->priv;
        struct gfar __iomem *regs = gfargrp->regs;
        struct gfar_priv_tx_q *tx_queue = NULL;
        struct gfar_priv_rx_q *rx_queue = NULL;
        int work_done = 0, work_done_per_q = 0;
        int i, budget_per_q = 0;
        int has_tx_work;
        unsigned long rstat_rxf;
        int num_act_queues;

        /* Clear IEVENT, so interrupts aren't called again
         * because of the packets that have already arrived
         */
        gfar_write(&regs->ievent, IEVENT_RTX_MASK);

        rstat_rxf = gfar_read(&regs->rstat) & RSTAT_RXF_MASK;

        num_act_queues = bitmap_weight(&rstat_rxf, MAX_RX_QS);
        if (num_act_queues)
                budget_per_q = budget/num_act_queues;

        while (1) {
                has_tx_work = 0;
                for_each_set_bit(i, &gfargrp->tx_bit_map, priv->num_tx_queues) {
                        tx_queue = priv->tx_queue[i];
                        /* run Tx cleanup to completion */
                        if (tx_queue->tx_skbuff[tx_queue->skb_dirtytx]) {
                                gfar_clean_tx_ring(tx_queue);
                                has_tx_work = 1;
                        }
                }

                for_each_set_bit(i, &gfargrp->rx_bit_map, priv->num_rx_queues) {
                        /* skip queue if not active */
                        if (!(rstat_rxf & (RSTAT_CLEAR_RXF0 >> i)))
                                continue;

                        rx_queue = priv->rx_queue[i];
                        work_done_per_q =
                                gfar_clean_rx_ring(rx_queue, budget_per_q);
                        work_done += work_done_per_q;

                        /* finished processing this queue */
                        if (work_done_per_q < budget_per_q) {
                                /* clear active queue hw indication */
                                gfar_write(&regs->rstat,
                                           RSTAT_CLEAR_RXF0 >> i);
                                rstat_rxf &= ~(RSTAT_CLEAR_RXF0 >> i);
                                num_act_queues--;

                                if (!num_act_queues)
                                        break;
                                /* recompute budget per Rx queue */
                                budget_per_q =
                                        (budget - work_done) / num_act_queues;
                        }
                }

                if (work_done >= budget)
                        break;

                if (!num_act_queues && !has_tx_work) {

                        napi_complete(napi);

                        /* Clear the halt bit in RSTAT */
                        gfar_write(&regs->rstat, gfargrp->rstat);

                        gfar_write(&regs->imask, IMASK_DEFAULT);

                        /* If we are coalescing interrupts, update the timer
                         * Otherwise, clear it
                         */
                        gfar_configure_coalescing(priv, gfargrp->rx_bit_map,
                                                  gfargrp->tx_bit_map);
                        break;
                }
        }

        return work_done;
}

#ifdef CONFIG_NET_POLL_CONTROLLER
/* Polling 'interrupt' - used by things like netconsole to send skbs
 * without having to re-enable interrupts. It's not called while
 * the interrupt routine is executing.
 */
static void gfar_netpoll(struct net_device *dev)
{
        struct gfar_private *priv = netdev_priv(dev);
        int i;

        /* If the device has multiple interrupts, run tx/rx */
        if (priv->device_flags & FSL_GIANFAR_DEV_HAS_MULTI_INTR) {
                for (i = 0; i < priv->num_grps; i++) {
                        struct gfar_priv_grp *grp = &priv->gfargrp[i];

                        disable_irq(gfar_irq(grp, TX)->irq);
                        disable_irq(gfar_irq(grp, RX)->irq);
                        disable_irq(gfar_irq(grp, ER)->irq);
                        gfar_interrupt(gfar_irq(grp, TX)->irq, grp);
                        enable_irq(gfar_irq(grp, ER)->irq);
                        enable_irq(gfar_irq(grp, RX)->irq);
                        enable_irq(gfar_irq(grp, TX)->irq);
                }
        } else {
                for (i = 0; i < priv->num_grps; i++) {
                        struct gfar_priv_grp *grp = &priv->gfargrp[i];

                        disable_irq(gfar_irq(grp, TX)->irq);
                        gfar_interrupt(gfar_irq(grp, TX)->irq, grp);
                        enable_irq(gfar_irq(grp, TX)->irq);
                }
        }
}
#endif

/* The interrupt handler for devices with one interrupt */
static irqreturn_t gfar_interrupt(int irq, void *grp_id)
{
        struct gfar_priv_grp *gfargrp = grp_id;

        /* Save ievent for future reference */
        u32 events = gfar_read(&gfargrp->regs->ievent);

        /* Check for reception */
        if (events & IEVENT_RX_MASK)
                gfar_receive(irq, grp_id);

        /* Check for transmit completion */
        if (events & IEVENT_TX_MASK)
                gfar_transmit(irq, grp_id);

        /* Check for errors */
        if (events & IEVENT_ERR_MASK)
                gfar_error(irq, grp_id);

        return IRQ_HANDLED;
}

/* Called every time the controller might need to be made
 * aware of new link state.  The PHY code conveys this
 * information through variables in the phydev structure, and this
 * function converts those variables into the appropriate
 * register values, and can bring down the device if needed.
 */
static void adjust_link(struct net_device *dev)
{
        struct gfar_private *priv = netdev_priv(dev);
        struct gfar __iomem *regs = priv->gfargrp[0].regs;
        unsigned long flags;
        struct phy_device *phydev = priv->phydev;
        int new_state = 0;

        local_irq_save(flags);
        lock_tx_qs(priv);

        if (phydev->link) {
                u32 tempval = gfar_read(&regs->maccfg2);
                u32 ecntrl = gfar_read(&regs->ecntrl);

                /* Now we make sure that we can be in full duplex mode.
                 * If not, we operate in half-duplex mode.
                 */
                if (phydev->duplex != priv->oldduplex) {
                        new_state = 1;
                        if (!(phydev->duplex))
                                tempval &= ~(MACCFG2_FULL_DUPLEX);
                        else
                                tempval |= MACCFG2_FULL_DUPLEX;

                        priv->oldduplex = phydev->duplex;
                }

                if (phydev->speed != priv->oldspeed) {
                        new_state = 1;
                        switch (phydev->speed) {
                        case 1000:
                                tempval =
                                    ((tempval & ~(MACCFG2_IF)) | MACCFG2_GMII);

                                ecntrl &= ~(ECNTRL_R100);
                                break;
                        case 100:
                        case 10:
                                tempval =
                                    ((tempval & ~(MACCFG2_IF)) | MACCFG2_MII);

                                /* Reduced mode distinguishes
                                 * between 10 and 100
                                 */
                                if (phydev->speed == SPEED_100)
                                        ecntrl |= ECNTRL_R100;
                                else
                                        ecntrl &= ~(ECNTRL_R100);
                                break;
                        default:
                                netif_warn(priv, link, dev,
                                           "Ack!  Speed (%d) is not 10/100/1000!\n",
                                           phydev->speed);
                                break;
                        }

                        priv->oldspeed = phydev->speed;
                }

                gfar_write(&regs->maccfg2, tempval);
                gfar_write(&regs->ecntrl, ecntrl);

                if (!priv->oldlink) {
                        new_state = 1;
                        priv->oldlink = 1;
                }
        } else if (priv->oldlink) {
                new_state = 1;
                priv->oldlink = 0;
                priv->oldspeed = 0;
                priv->oldduplex = -1;
        }

        if (new_state && netif_msg_link(priv))
                phy_print_status(phydev);
        unlock_tx_qs(priv);
        local_irq_restore(flags);
}

/* Update the hash table based on the current list of multicast
 * addresses we subscribe to.  Also, change the promiscuity of
 * the device based on the flags (this function is called
 * whenever dev->flags is changed
 */
static void gfar_set_multi(struct net_device *dev)
{
        struct netdev_hw_addr *ha;
        struct gfar_private *priv = netdev_priv(dev);
        struct gfar __iomem *regs = priv->gfargrp[0].regs;
        u32 tempval;

        if (dev->flags & IFF_PROMISC) {
                /* Set RCTRL to PROM */
                tempval = gfar_read(&regs->rctrl);
                tempval |= RCTRL_PROM;
                gfar_write(&regs->rctrl, tempval);
        } else {
                /* Set RCTRL to not PROM */
                tempval = gfar_read(&regs->rctrl);
                tempval &= ~(RCTRL_PROM);
                gfar_write(&regs->rctrl, tempval);
        }

        if (dev->flags & IFF_ALLMULTI) {
                /* Set the hash to rx all multicast frames */
                gfar_write(&regs->igaddr0, 0xffffffff);
                gfar_write(&regs->igaddr1, 0xffffffff);
                gfar_write(&regs->igaddr2, 0xffffffff);
                gfar_write(&regs->igaddr3, 0xffffffff);
                gfar_write(&regs->igaddr4, 0xffffffff);
                gfar_write(&regs->igaddr5, 0xffffffff);
                gfar_write(&regs->igaddr6, 0xffffffff);
                gfar_write(&regs->igaddr7, 0xffffffff);
                gfar_write(&regs->gaddr0, 0xffffffff);
                gfar_write(&regs->gaddr1, 0xffffffff);
                gfar_write(&regs->gaddr2, 0xffffffff);
                gfar_write(&regs->gaddr3, 0xffffffff);
                gfar_write(&regs->gaddr4, 0xffffffff);
                gfar_write(&regs->gaddr5, 0xffffffff);
                gfar_write(&regs->gaddr6, 0xffffffff);
                gfar_write(&regs->gaddr7, 0xffffffff);
        } else {
                int em_num;
                int idx;

                /* zero out the hash */
                gfar_write(&regs->igaddr0, 0x0);
                gfar_write(&regs->igaddr1, 0x0);
                gfar_write(&regs->igaddr2, 0x0);
                gfar_write(&regs->igaddr3, 0x0);
                gfar_write(&regs->igaddr4, 0x0);
                gfar_write(&regs->igaddr5, 0x0);
                gfar_write(&regs->igaddr6, 0x0);
                gfar_write(&regs->igaddr7, 0x0);
                gfar_write(&regs->gaddr0, 0x0);
                gfar_write(&regs->gaddr1, 0x0);
                gfar_write(&regs->gaddr2, 0x0);
                gfar_write(&regs->gaddr3, 0x0);
                gfar_write(&regs->gaddr4, 0x0);
                gfar_write(&regs->gaddr5, 0x0);
                gfar_write(&regs->gaddr6, 0x0);
                gfar_write(&regs->gaddr7, 0x0);

                /* If we have extended hash tables, we need to
                 * clear the exact match registers to prepare for
                 * setting them
                 */
                if (priv->extended_hash) {
                        em_num = GFAR_EM_NUM + 1;
                        gfar_clear_exact_match(dev);
                        idx = 1;
                } else {
                        idx = 0;
                        em_num = 0;
                }

                if (netdev_mc_empty(dev))
                        return;

                /* Parse the list, and set the appropriate bits */
                netdev_for_each_mc_addr(ha, dev) {
                        if (idx < em_num) {
                                gfar_set_mac_for_addr(dev, idx, ha->addr);
                                idx++;
                        } else
                                gfar_set_hash_for_addr(dev, ha->addr);
                }
        }
}


/* Clears each of the exact match registers to zero, so they
 * don't interfere with normal reception
 */
static void gfar_clear_exact_match(struct net_device *dev)
{
        int idx;
        static const u8 zero_arr[ETH_ALEN] = {0, 0, 0, 0, 0, 0};

        for (idx = 1; idx < GFAR_EM_NUM + 1; idx++)
                gfar_set_mac_for_addr(dev, idx, zero_arr);
}

/* Set the appropriate hash bit for the given addr */
/* The algorithm works like so:
 * 1) Take the Destination Address (ie the multicast address), and
 * do a CRC on it (little endian), and reverse the bits of the
 * result.
 * 2) Use the 8 most significant bits as a hash into a 256-entry
 * table.  The table is controlled through 8 32-bit registers:
 * gaddr0-7.  gaddr0's MSB is entry 0, and gaddr7's LSB is
 * gaddr7.  This means that the 3 most significant bits in the
 * hash index which gaddr register to use, and the 5 other bits
 * indicate which bit (assuming an IBM numbering scheme, which
 * for PowerPC (tm) is usually the case) in the register holds
 * the entry.
 */
static void gfar_set_hash_for_addr(struct net_device *dev, u8 *addr)
{
        u32 tempval;
        struct gfar_private *priv = netdev_priv(dev);
        u32 result = ether_crc(ETH_ALEN, addr);
        int width = priv->hash_width;
        u8 whichbit = (result >> (32 - width)) & 0x1f;
        u8 whichreg = result >> (32 - width + 5);
        u32 value = (1 << (31-whichbit));

        tempval = gfar_read(priv->hash_regs[whichreg]);
        tempval |= value;
        gfar_write(priv->hash_regs[whichreg], tempval);
}


/* There are multiple MAC Address register pairs on some controllers
 * This function sets the numth pair to a given address
 */
static void gfar_set_mac_for_addr(struct net_device *dev, int num,
                                  const u8 *addr)
{
        struct gfar_private *priv = netdev_priv(dev);
        struct gfar __iomem *regs = priv->gfargrp[0].regs;
        int idx;
        char tmpbuf[ETH_ALEN];
        u32 tempval;
        u32 __iomem *macptr = &regs->macstnaddr1;

        macptr += num*2;

        /* Now copy it into the mac registers backwards, cuz
         * little endian is silly
         */
        for (idx = 0; idx < ETH_ALEN; idx++)
                tmpbuf[ETH_ALEN - 1 - idx] = addr[idx];

        gfar_write(macptr, *((u32 *) (tmpbuf)));

        tempval = *((u32 *) (tmpbuf + 4));

        gfar_write(macptr+1, tempval);
}

/* GFAR error interrupt handler */
static irqreturn_t gfar_error(int irq, void *grp_id)
{
        struct gfar_priv_grp *gfargrp = grp_id;
        struct gfar __iomem *regs = gfargrp->regs;
        struct gfar_private *priv= gfargrp->priv;
        struct net_device *dev = priv->ndev;

        /* Save ievent for future reference */
        u32 events = gfar_read(&regs->ievent);

        /* Clear IEVENT */
        gfar_write(&regs->ievent, events & IEVENT_ERR_MASK);

        /* Magic Packet is not an error. */
        if ((priv->device_flags & FSL_GIANFAR_DEV_HAS_MAGIC_PACKET) &&
            (events & IEVENT_MAG))
                events &= ~IEVENT_MAG;

        /* Hmm... */
        if (netif_msg_rx_err(priv) || netif_msg_tx_err(priv))
                netdev_dbg(dev,
                           "error interrupt (ievent=0x%08x imask=0x%08x)\n",
                           events, gfar_read(&regs->imask));

        /* Update the error counters */
        if (events & IEVENT_TXE) {
                dev->stats.tx_errors++;

                if (events & IEVENT_LC)
                        dev->stats.tx_window_errors++;
                if (events & IEVENT_CRL)
                        dev->stats.tx_aborted_errors++;
                if (events & IEVENT_XFUN) {
                        unsigned long flags;

                        netif_dbg(priv, tx_err, dev,
                                  "TX FIFO underrun, packet dropped\n");
                        dev->stats.tx_dropped++;
                        atomic64_inc(&priv->extra_stats.tx_underrun);

                        local_irq_save(flags);
                        lock_tx_qs(priv);

                        /* Reactivate the Tx Queues */
                        gfar_write(&regs->tstat, gfargrp->tstat);

                        unlock_tx_qs(priv);
                        local_irq_restore(flags);
                }
                netif_dbg(priv, tx_err, dev, "Transmit Error\n");
        }
        if (events & IEVENT_BSY) {
                dev->stats.rx_errors++;
                atomic64_inc(&priv->extra_stats.rx_bsy);

                gfar_receive(irq, grp_id);

                netif_dbg(priv, rx_err, dev, "busy error (rstat: %x)\n",
                          gfar_read(&regs->rstat));
        }
        if (events & IEVENT_BABR) {
                dev->stats.rx_errors++;
                atomic64_inc(&priv->extra_stats.rx_babr);

                netif_dbg(priv, rx_err, dev, "babbling RX error\n");
        }
        if (events & IEVENT_EBERR) {
                atomic64_inc(&priv->extra_stats.eberr);
                netif_dbg(priv, rx_err, dev, "bus error\n");
        }
        if (events & IEVENT_RXC)
                netif_dbg(priv, rx_status, dev, "control frame\n");

        if (events & IEVENT_BABT) {
                atomic64_inc(&priv->extra_stats.tx_babt);
                netif_dbg(priv, tx_err, dev, "babbling TX error\n");
        }
        return IRQ_HANDLED;
}

static struct of_device_id gfar_match[] =
{
        {
                .type = "network",
                .compatible = "gianfar",
        },
        {
                .compatible = "fsl,etsec2",
        },
        {},
};
MODULE_DEVICE_TABLE(of, gfar_match);

/* Structure for a device driver */
static struct platform_driver gfar_driver = {
        .driver = {
                .name = "fsl-gianfar",
                .owner = THIS_MODULE,
                .pm = GFAR_PM_OPS,
                .of_match_table = gfar_match,
        },
        .probe = gfar_probe,
        .remove = gfar_remove,
};

module_platform_driver(gfar_driver);