// SPDX-License-Identifier: GPL-2.0-or-later
/*
 * Aeroflex Gaisler GRETH 10/100/1G Ethernet MAC.
 *
 * 2005-2010 (c) Aeroflex Gaisler AB
 *
 * This driver supports GRETH 10/100 and GRETH 10/100/1G Ethernet MACs
 * available in the GRLIB VHDL IP core library.
 *
 * Full documentation of both cores can be found here:
 * https://www.gaisler.com/products/grlib/grip.pdf
 *
 * The Gigabit version supports scatter/gather DMA, any alignment of
 * buffers and checksum offloading.
 *
 * Contributors: Kristoffer Glembo
 *               Daniel Hellstrom
 *               Marko Isomaki
 */

#include <linux/dma-mapping.h>
#include <linux/module.h>
#include <linux/uaccess.h>
#include <linux/interrupt.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/ethtool.h>
#include <linux/skbuff.h>
#include <linux/io.h>
#include <linux/crc32.h>
#include <linux/mii.h>
#include <linux/of.h>
#include <linux/of_net.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <asm/cacheflush.h>
#include <asm/byteorder.h>

#ifdef CONFIG_SPARC
#include <asm/idprom.h>
#endif

#include "greth.h"

#define GRETH_DEF_MSG_ENABLE      \
        (NETIF_MSG_DRV          | \
         NETIF_MSG_PROBE        | \
         NETIF_MSG_LINK         | \
         NETIF_MSG_IFDOWN       | \
         NETIF_MSG_IFUP         | \
         NETIF_MSG_RX_ERR       | \
         NETIF_MSG_TX_ERR)

static int greth_debug = -1;    /* -1 == use GRETH_DEF_MSG_ENABLE as value */
module_param(greth_debug, int, 0);
MODULE_PARM_DESC(greth_debug, "GRETH bitmapped debugging message enable value");

/* Accept MAC address of the form macaddr=0x08,0x00,0x20,0x30,0x40,0x50 */
static int macaddr[6];
module_param_array(macaddr, int, NULL, 0);
MODULE_PARM_DESC(macaddr, "GRETH Ethernet MAC address");

static int greth_edcl = 1;
module_param(greth_edcl, int, 0);
MODULE_PARM_DESC(greth_edcl, "GRETH EDCL usage indicator. Set to 1 if EDCL is used.");

static int greth_open(struct net_device *dev);
static netdev_tx_t greth_start_xmit(struct sk_buff *skb,
           struct net_device *dev);
static netdev_tx_t greth_start_xmit_gbit(struct sk_buff *skb,
           struct net_device *dev);
static int greth_rx(struct net_device *dev, int limit);
static int greth_rx_gbit(struct net_device *dev, int limit);
static void greth_clean_tx(struct net_device *dev);
static void greth_clean_tx_gbit(struct net_device *dev);
static irqreturn_t greth_interrupt(int irq, void *dev_id);
static int greth_close(struct net_device *dev);
static int greth_set_mac_add(struct net_device *dev, void *p);
static void greth_set_multicast_list(struct net_device *dev);

#define GRETH_REGLOAD(a)            (be32_to_cpu(__raw_readl(&(a))))
#define GRETH_REGSAVE(a, v)         (__raw_writel(cpu_to_be32(v), &(a)))
#define GRETH_REGORIN(a, v)         (GRETH_REGSAVE(a, (GRETH_REGLOAD(a) | (v))))
#define GRETH_REGANDIN(a, v)        (GRETH_REGSAVE(a, (GRETH_REGLOAD(a) & (v))))

#define NEXT_TX(N)      (((N) + 1) & GRETH_TXBD_NUM_MASK)
#define SKIP_TX(N, C)   (((N) + C) & GRETH_TXBD_NUM_MASK)
#define NEXT_RX(N)      (((N) + 1) & GRETH_RXBD_NUM_MASK)

static void greth_print_rx_packet(void *addr, int len)
{
        print_hex_dump(KERN_DEBUG, "RX: ", DUMP_PREFIX_OFFSET, 16, 1,
                        addr, len, true);
}

static void greth_print_tx_packet(struct sk_buff *skb)
{
        int i;
        int length;

        if (skb_shinfo(skb)->nr_frags == 0)
                length = skb->len;
        else
                length = skb_headlen(skb);

        print_hex_dump(KERN_DEBUG, "TX: ", DUMP_PREFIX_OFFSET, 16, 1,
                        skb->data, length, true);

        for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) {

                print_hex_dump(KERN_DEBUG, "TX: ", DUMP_PREFIX_OFFSET, 16, 1,
                               skb_frag_address(&skb_shinfo(skb)->frags[i]),
                               skb_frag_size(&skb_shinfo(skb)->frags[i]), true);
        }
}

static inline void greth_enable_tx(struct greth_private *greth)
{
        wmb();
        GRETH_REGORIN(greth->regs->control, GRETH_TXEN);
}

static inline void greth_enable_tx_and_irq(struct greth_private *greth)
{
        wmb(); /* BDs must been written to memory before enabling TX */
        GRETH_REGORIN(greth->regs->control, GRETH_TXEN | GRETH_TXI);
}

static inline void greth_disable_tx(struct greth_private *greth)
{
        GRETH_REGANDIN(greth->regs->control, ~GRETH_TXEN);
}

static inline void greth_enable_rx(struct greth_private *greth)
{
        wmb();
        GRETH_REGORIN(greth->regs->control, GRETH_RXEN);
}

static inline void greth_disable_rx(struct greth_private *greth)
{
        GRETH_REGANDIN(greth->regs->control, ~GRETH_RXEN);
}

static inline void greth_enable_irqs(struct greth_private *greth)
{
        GRETH_REGORIN(greth->regs->control, GRETH_RXI | GRETH_TXI);
}

static inline void greth_disable_irqs(struct greth_private *greth)
{
        GRETH_REGANDIN(greth->regs->control, ~(GRETH_RXI|GRETH_TXI));
}

static inline void greth_write_bd(u32 *bd, u32 val)
{
        __raw_writel(cpu_to_be32(val), bd);
}

static inline u32 greth_read_bd(u32 *bd)
{
        return be32_to_cpu(__raw_readl(bd));
}

static void greth_clean_rings(struct greth_private *greth)
{
        int i;
        struct greth_bd *rx_bdp = greth->rx_bd_base;
        struct greth_bd *tx_bdp = greth->tx_bd_base;

        if (greth->gbit_mac) {

                /* Free and unmap RX buffers */
                for (i = 0; i < GRETH_RXBD_NUM; i++, rx_bdp++) {
                        if (greth->rx_skbuff[i] != NULL) {
                                dev_kfree_skb(greth->rx_skbuff[i]);
                                dma_unmap_single(greth->dev,
                                                 greth_read_bd(&rx_bdp->addr),
                                                 MAX_FRAME_SIZE+NET_IP_ALIGN,
                                                 DMA_FROM_DEVICE);
                        }
                }

                /* TX buffers */
                while (greth->tx_free < GRETH_TXBD_NUM) {

                        struct sk_buff *skb = greth->tx_skbuff[greth->tx_last];
                        int nr_frags = skb_shinfo(skb)->nr_frags;
                        tx_bdp = greth->tx_bd_base + greth->tx_last;
                        greth->tx_last = NEXT_TX(greth->tx_last);

                        dma_unmap_single(greth->dev,
                                         greth_read_bd(&tx_bdp->addr),
                                         skb_headlen(skb),
                                         DMA_TO_DEVICE);

                        for (i = 0; i < nr_frags; i++) {
                                skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
                                tx_bdp = greth->tx_bd_base + greth->tx_last;

                                dma_unmap_page(greth->dev,
                                               greth_read_bd(&tx_bdp->addr),
                                               skb_frag_size(frag),
                                               DMA_TO_DEVICE);

                                greth->tx_last = NEXT_TX(greth->tx_last);
                        }
                        greth->tx_free += nr_frags+1;
                        dev_kfree_skb(skb);
                }


        } else { /* 10/100 Mbps MAC */

                for (i = 0; i < GRETH_RXBD_NUM; i++, rx_bdp++) {
                        kfree(greth->rx_bufs[i]);
                        dma_unmap_single(greth->dev,
                                         greth_read_bd(&rx_bdp->addr),
                                         MAX_FRAME_SIZE,
                                         DMA_FROM_DEVICE);
                }
                for (i = 0; i < GRETH_TXBD_NUM; i++, tx_bdp++) {
                        kfree(greth->tx_bufs[i]);
                        dma_unmap_single(greth->dev,
                                         greth_read_bd(&tx_bdp->addr),
                                         MAX_FRAME_SIZE,
                                         DMA_TO_DEVICE);
                }
        }
}

static int greth_init_rings(struct greth_private *greth)
{
        struct sk_buff *skb;
        struct greth_bd *rx_bd, *tx_bd;
        u32 dma_addr;
        int i;

        rx_bd = greth->rx_bd_base;
        tx_bd = greth->tx_bd_base;

        /* Initialize descriptor rings and buffers */
        if (greth->gbit_mac) {

                for (i = 0; i < GRETH_RXBD_NUM; i++) {
                        skb = netdev_alloc_skb(greth->netdev, MAX_FRAME_SIZE+NET_IP_ALIGN);
                        if (skb == NULL) {
                                if (netif_msg_ifup(greth))
                                        dev_err(greth->dev, "Error allocating DMA ring.\n");
                                goto cleanup;
                        }
                        skb_reserve(skb, NET_IP_ALIGN);
                        dma_addr = dma_map_single(greth->dev,
                                                  skb->data,
                                                  MAX_FRAME_SIZE+NET_IP_ALIGN,
                                                  DMA_FROM_DEVICE);

                        if (dma_mapping_error(greth->dev, dma_addr)) {
                                if (netif_msg_ifup(greth))
                                        dev_err(greth->dev, "Could not create initial DMA mapping\n");
                                dev_kfree_skb(skb);
                                goto cleanup;
                        }
                        greth->rx_skbuff[i] = skb;
                        greth_write_bd(&rx_bd[i].addr, dma_addr);
                        greth_write_bd(&rx_bd[i].stat, GRETH_BD_EN | GRETH_BD_IE);
                }

        } else {

                /* 10/100 MAC uses a fixed set of buffers and copy to/from SKBs */
                for (i = 0; i < GRETH_RXBD_NUM; i++) {

                        greth->rx_bufs[i] = kmalloc(MAX_FRAME_SIZE, GFP_KERNEL);

                        if (greth->rx_bufs[i] == NULL) {
                                if (netif_msg_ifup(greth))
                                        dev_err(greth->dev, "Error allocating DMA ring.\n");
                                goto cleanup;
                        }

                        dma_addr = dma_map_single(greth->dev,
                                                  greth->rx_bufs[i],
                                                  MAX_FRAME_SIZE,
                                                  DMA_FROM_DEVICE);

                        if (dma_mapping_error(greth->dev, dma_addr)) {
                                if (netif_msg_ifup(greth))
                                        dev_err(greth->dev, "Could not create initial DMA mapping\n");
                                goto cleanup;
                        }
                        greth_write_bd(&rx_bd[i].addr, dma_addr);
                        greth_write_bd(&rx_bd[i].stat, GRETH_BD_EN | GRETH_BD_IE);
                }
                for (i = 0; i < GRETH_TXBD_NUM; i++) {

                        greth->tx_bufs[i] = kmalloc(MAX_FRAME_SIZE, GFP_KERNEL);

                        if (greth->tx_bufs[i] == NULL) {
                                if (netif_msg_ifup(greth))
                                        dev_err(greth->dev, "Error allocating DMA ring.\n");
                                goto cleanup;
                        }

                        dma_addr = dma_map_single(greth->dev,
                                                  greth->tx_bufs[i],
                                                  MAX_FRAME_SIZE,
                                                  DMA_TO_DEVICE);

                        if (dma_mapping_error(greth->dev, dma_addr)) {
                                if (netif_msg_ifup(greth))
                                        dev_err(greth->dev, "Could not create initial DMA mapping\n");
                                goto cleanup;
                        }
                        greth_write_bd(&tx_bd[i].addr, dma_addr);
                        greth_write_bd(&tx_bd[i].stat, 0);
                }
        }
        greth_write_bd(&rx_bd[GRETH_RXBD_NUM - 1].stat,
                       greth_read_bd(&rx_bd[GRETH_RXBD_NUM - 1].stat) | GRETH_BD_WR);

        /* Initialize pointers. */
        greth->rx_cur = 0;
        greth->tx_next = 0;
        greth->tx_last = 0;
        greth->tx_free = GRETH_TXBD_NUM;

        /* Initialize descriptor base address */
        GRETH_REGSAVE(greth->regs->tx_desc_p, greth->tx_bd_base_phys);
        GRETH_REGSAVE(greth->regs->rx_desc_p, greth->rx_bd_base_phys);

        return 0;

cleanup:
        greth_clean_rings(greth);
        return -ENOMEM;
}

static int greth_open(struct net_device *dev)
{
        struct greth_private *greth = netdev_priv(dev);
        int err;

        err = greth_init_rings(greth);
        if (err) {
                if (netif_msg_ifup(greth))
                        dev_err(&dev->dev, "Could not allocate memory for DMA rings\n");
                return err;
        }

        err = request_irq(greth->irq, greth_interrupt, 0, "eth", (void *) dev);
        if (err) {
                if (netif_msg_ifup(greth))
                        dev_err(&dev->dev, "Could not allocate interrupt %d\n", dev->irq);
                greth_clean_rings(greth);
                return err;
        }

        if (netif_msg_ifup(greth))
                dev_dbg(&dev->dev, " starting queue\n");
        netif_start_queue(dev);

        GRETH_REGSAVE(greth->regs->status, 0xFF);

        napi_enable(&greth->napi);

        greth_enable_irqs(greth);
        greth_enable_tx(greth);
        greth_enable_rx(greth);
        return 0;

}

static int greth_close(struct net_device *dev)
{
        struct greth_private *greth = netdev_priv(dev);

        napi_disable(&greth->napi);

        greth_disable_irqs(greth);
        greth_disable_tx(greth);
        greth_disable_rx(greth);

        netif_stop_queue(dev);

        free_irq(greth->irq, (void *) dev);

        greth_clean_rings(greth);

        return 0;
}

static netdev_tx_t
greth_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
        struct greth_private *greth = netdev_priv(dev);
        struct greth_bd *bdp;
        int err = NETDEV_TX_OK;
        u32 status, dma_addr, ctrl;
        unsigned long flags;

        /* Clean TX Ring */
        greth_clean_tx(greth->netdev);

        if (unlikely(greth->tx_free <= 0)) {
                spin_lock_irqsave(&greth->devlock, flags);/*save from poll/irq*/
                ctrl = GRETH_REGLOAD(greth->regs->control);
                /* Enable TX IRQ only if not already in poll() routine */
                if (ctrl & GRETH_RXI)
                        GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_TXI);
                netif_stop_queue(dev);
                spin_unlock_irqrestore(&greth->devlock, flags);
                return NETDEV_TX_BUSY;
        }

        if (netif_msg_pktdata(greth))
                greth_print_tx_packet(skb);


        if (unlikely(skb->len > MAX_FRAME_SIZE)) {
                dev->stats.tx_errors++;
                goto out;
        }

        bdp = greth->tx_bd_base + greth->tx_next;
        dma_addr = greth_read_bd(&bdp->addr);

        memcpy((unsigned char *) phys_to_virt(dma_addr), skb->data, skb->len);

        dma_sync_single_for_device(greth->dev, dma_addr, skb->len, DMA_TO_DEVICE);

        status = GRETH_BD_EN | GRETH_BD_IE | (skb->len & GRETH_BD_LEN);
        greth->tx_bufs_length[greth->tx_next] = skb->len & GRETH_BD_LEN;

        /* Wrap around descriptor ring */
        if (greth->tx_next == GRETH_TXBD_NUM_MASK) {
                status |= GRETH_BD_WR;
        }

        greth->tx_next = NEXT_TX(greth->tx_next);
        greth->tx_free--;

        /* Write descriptor control word and enable transmission */
        greth_write_bd(&bdp->stat, status);
        spin_lock_irqsave(&greth->devlock, flags); /*save from poll/irq*/
        greth_enable_tx(greth);
        spin_unlock_irqrestore(&greth->devlock, flags);

out:
        dev_kfree_skb(skb);
        return err;
}

static inline u16 greth_num_free_bds(u16 tx_last, u16 tx_next)
{
        if (tx_next < tx_last)
                return (tx_last - tx_next) - 1;
        else
                return GRETH_TXBD_NUM - (tx_next - tx_last) - 1;
}

static netdev_tx_t
greth_start_xmit_gbit(struct sk_buff *skb, struct net_device *dev)
{
        struct greth_private *greth = netdev_priv(dev);
        struct greth_bd *bdp;
        u32 status, dma_addr;
        int curr_tx, nr_frags, i, err = NETDEV_TX_OK;
        unsigned long flags;
        u16 tx_last;

        nr_frags = skb_shinfo(skb)->nr_frags;
        tx_last = greth->tx_last;
        rmb(); /* tx_last is updated by the poll task */

        if (greth_num_free_bds(tx_last, greth->tx_next) < nr_frags + 1) {
                netif_stop_queue(dev);
                err = NETDEV_TX_BUSY;
                goto out;
        }

        if (netif_msg_pktdata(greth))
                greth_print_tx_packet(skb);

        if (unlikely(skb->len > MAX_FRAME_SIZE)) {
                dev->stats.tx_errors++;
                goto len_error;
        }

        /* Save skb pointer. */
        greth->tx_skbuff[greth->tx_next] = skb;

        /* Linear buf */
        if (nr_frags != 0)
                status = GRETH_TXBD_MORE;
        else
                status = GRETH_BD_IE;

        if (skb->ip_summed == CHECKSUM_PARTIAL)
                status |= GRETH_TXBD_CSALL;
        status |= skb_headlen(skb) & GRETH_BD_LEN;
        if (greth->tx_next == GRETH_TXBD_NUM_MASK)
                status |= GRETH_BD_WR;


        bdp = greth->tx_bd_base + greth->tx_next;
        greth_write_bd(&bdp->stat, status);
        dma_addr = dma_map_single(greth->dev, skb->data, skb_headlen(skb), DMA_TO_DEVICE);

        if (unlikely(dma_mapping_error(greth->dev, dma_addr)))
                goto map_error;

        greth_write_bd(&bdp->addr, dma_addr);

        curr_tx = NEXT_TX(greth->tx_next);

        /* Frags */
        for (i = 0; i < nr_frags; i++) {
                skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
                greth->tx_skbuff[curr_tx] = NULL;
                bdp = greth->tx_bd_base + curr_tx;

                status = GRETH_BD_EN;
                if (skb->ip_summed == CHECKSUM_PARTIAL)
                        status |= GRETH_TXBD_CSALL;
                status |= skb_frag_size(frag) & GRETH_BD_LEN;

                /* Wrap around descriptor ring */
                if (curr_tx == GRETH_TXBD_NUM_MASK)
                        status |= GRETH_BD_WR;

                /* More fragments left */
                if (i < nr_frags - 1)
                        status |= GRETH_TXBD_MORE;
                else
                        status |= GRETH_BD_IE; /* enable IRQ on last fragment */

                greth_write_bd(&bdp->stat, status);

                dma_addr = skb_frag_dma_map(greth->dev, frag, 0, skb_frag_size(frag),
                                            DMA_TO_DEVICE);

                if (unlikely(dma_mapping_error(greth->dev, dma_addr)))
                        goto frag_map_error;

                greth_write_bd(&bdp->addr, dma_addr);

                curr_tx = NEXT_TX(curr_tx);
        }

        wmb();

        /* Enable the descriptor chain by enabling the first descriptor */
        bdp = greth->tx_bd_base + greth->tx_next;
        greth_write_bd(&bdp->stat,
                       greth_read_bd(&bdp->stat) | GRETH_BD_EN);

        spin_lock_irqsave(&greth->devlock, flags); /*save from poll/irq*/
        greth->tx_next = curr_tx;
        greth_enable_tx_and_irq(greth);
        spin_unlock_irqrestore(&greth->devlock, flags);

        return NETDEV_TX_OK;

frag_map_error:
        /* Unmap SKB mappings that succeeded and disable descriptor */
        for (i = 0; greth->tx_next + i != curr_tx; i++) {
                bdp = greth->tx_bd_base + greth->tx_next + i;
                dma_unmap_single(greth->dev,
                                 greth_read_bd(&bdp->addr),
                                 greth_read_bd(&bdp->stat) & GRETH_BD_LEN,
                                 DMA_TO_DEVICE);
                greth_write_bd(&bdp->stat, 0);
        }
map_error:
        if (net_ratelimit())
                dev_warn(greth->dev, "Could not create TX DMA mapping\n");
len_error:
        dev_kfree_skb(skb);
out:
        return err;
}

static irqreturn_t greth_interrupt(int irq, void *dev_id)
{
        struct net_device *dev = dev_id;
        struct greth_private *greth;
        u32 status, ctrl;
        irqreturn_t retval = IRQ_NONE;

        greth = netdev_priv(dev);

        spin_lock(&greth->devlock);

        /* Get the interrupt events that caused us to be here. */
        status = GRETH_REGLOAD(greth->regs->status);

        /* Must see if interrupts are enabled also, INT_TX|INT_RX flags may be
         * set regardless of whether IRQ is enabled or not. Especially
         * important when shared IRQ.
         */
        ctrl = GRETH_REGLOAD(greth->regs->control);

        /* Handle rx and tx interrupts through poll */
        if (((status & (GRETH_INT_RE | GRETH_INT_RX)) && (ctrl & GRETH_RXI)) ||
            ((status & (GRETH_INT_TE | GRETH_INT_TX)) && (ctrl & GRETH_TXI))) {
                retval = IRQ_HANDLED;

                /* Disable interrupts and schedule poll() */
                greth_disable_irqs(greth);
                napi_schedule(&greth->napi);
        }

        spin_unlock(&greth->devlock);

        return retval;
}

static void greth_clean_tx(struct net_device *dev)
{
        struct greth_private *greth;
        struct greth_bd *bdp;
        u32 stat;

        greth = netdev_priv(dev);

        while (1) {
                bdp = greth->tx_bd_base + greth->tx_last;
                GRETH_REGSAVE(greth->regs->status, GRETH_INT_TE | GRETH_INT_TX);
                mb();
                stat = greth_read_bd(&bdp->stat);

                if (unlikely(stat & GRETH_BD_EN))
                        break;

                if (greth->tx_free == GRETH_TXBD_NUM)
                        break;

                /* Check status for errors */
                if (unlikely(stat & GRETH_TXBD_STATUS)) {
                        dev->stats.tx_errors++;
                        if (stat & GRETH_TXBD_ERR_AL)
                                dev->stats.tx_aborted_errors++;
                        if (stat & GRETH_TXBD_ERR_UE)
                                dev->stats.tx_fifo_errors++;
                }
                dev->stats.tx_packets++;
                dev->stats.tx_bytes += greth->tx_bufs_length[greth->tx_last];
                greth->tx_last = NEXT_TX(greth->tx_last);
                greth->tx_free++;
        }

        if (greth->tx_free > 0) {
                netif_wake_queue(dev);
        }
}

static inline void greth_update_tx_stats(struct net_device *dev, u32 stat)
{
        /* Check status for errors */
        if (unlikely(stat & GRETH_TXBD_STATUS)) {
                dev->stats.tx_errors++;
                if (stat & GRETH_TXBD_ERR_AL)
                        dev->stats.tx_aborted_errors++;
                if (stat & GRETH_TXBD_ERR_UE)
                        dev->stats.tx_fifo_errors++;
                if (stat & GRETH_TXBD_ERR_LC)
                        dev->stats.tx_aborted_errors++;
        }
        dev->stats.tx_packets++;
}

static void greth_clean_tx_gbit(struct net_device *dev)
{
        struct greth_private *greth;
        struct greth_bd *bdp, *bdp_last_frag;
        struct sk_buff *skb = NULL;
        u32 stat;
        int nr_frags, i;
        u16 tx_last;

        greth = netdev_priv(dev);
        tx_last = greth->tx_last;

        while (tx_last != greth->tx_next) {

                skb = greth->tx_skbuff[tx_last];

                nr_frags = skb_shinfo(skb)->nr_frags;

                /* We only clean fully completed SKBs */
                bdp_last_frag = greth->tx_bd_base + SKIP_TX(tx_last, nr_frags);

                GRETH_REGSAVE(greth->regs->status, GRETH_INT_TE | GRETH_INT_TX);
                mb();
                stat = greth_read_bd(&bdp_last_frag->stat);

                if (stat & GRETH_BD_EN)
                        break;

                greth->tx_skbuff[tx_last] = NULL;

                greth_update_tx_stats(dev, stat);
                dev->stats.tx_bytes += skb->len;

                bdp = greth->tx_bd_base + tx_last;

                tx_last = NEXT_TX(tx_last);

                dma_unmap_single(greth->dev,
                                 greth_read_bd(&bdp->addr),
                                 skb_headlen(skb),
                                 DMA_TO_DEVICE);

                for (i = 0; i < nr_frags; i++) {
                        skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
                        bdp = greth->tx_bd_base + tx_last;

                        dma_unmap_page(greth->dev,
                                       greth_read_bd(&bdp->addr),
                                       skb_frag_size(frag),
                                       DMA_TO_DEVICE);

                        tx_last = NEXT_TX(tx_last);
                }
                dev_kfree_skb(skb);
        }
        if (skb) { /* skb is set only if the above while loop was entered */
                wmb();
                greth->tx_last = tx_last;

                if (netif_queue_stopped(dev) &&
                    (greth_num_free_bds(tx_last, greth->tx_next) >
                    (MAX_SKB_FRAGS+1)))
                        netif_wake_queue(dev);
        }
}

static int greth_rx(struct net_device *dev, int limit)
{
        struct greth_private *greth;
        struct greth_bd *bdp;
        struct sk_buff *skb;
        int pkt_len;
        int bad, count;
        u32 status, dma_addr;
        unsigned long flags;

        greth = netdev_priv(dev);

        for (count = 0; count < limit; ++count) {

                bdp = greth->rx_bd_base + greth->rx_cur;
                GRETH_REGSAVE(greth->regs->status, GRETH_INT_RE | GRETH_INT_RX);
                mb();
                status = greth_read_bd(&bdp->stat);

                if (unlikely(status & GRETH_BD_EN)) {
                        break;
                }

                dma_addr = greth_read_bd(&bdp->addr);
                bad = 0;

                /* Check status for errors. */
                if (unlikely(status & GRETH_RXBD_STATUS)) {
                        if (status & GRETH_RXBD_ERR_FT) {
                                dev->stats.rx_length_errors++;
                                bad = 1;
                        }
                        if (status & (GRETH_RXBD_ERR_AE | GRETH_RXBD_ERR_OE)) {
                                dev->stats.rx_frame_errors++;
                                bad = 1;
                        }
                        if (status & GRETH_RXBD_ERR_CRC) {
                                dev->stats.rx_crc_errors++;
                                bad = 1;
                        }
                }
                if (unlikely(bad)) {
                        dev->stats.rx_errors++;

                } else {

                        pkt_len = status & GRETH_BD_LEN;

                        skb = netdev_alloc_skb(dev, pkt_len + NET_IP_ALIGN);

                        if (unlikely(skb == NULL)) {

                                if (net_ratelimit())
                                        dev_warn(&dev->dev, "low on memory - " "packet dropped\n");

                                dev->stats.rx_dropped++;

                        } else {
                                skb_reserve(skb, NET_IP_ALIGN);

                                dma_sync_single_for_cpu(greth->dev,
                                                        dma_addr,
                                                        pkt_len,
                                                        DMA_FROM_DEVICE);

                                if (netif_msg_pktdata(greth))
                                        greth_print_rx_packet(phys_to_virt(dma_addr), pkt_len);

                                skb_put_data(skb, phys_to_virt(dma_addr),
                                             pkt_len);

                                skb->protocol = eth_type_trans(skb, dev);
                                dev->stats.rx_bytes += pkt_len;
                                dev->stats.rx_packets++;
                                netif_receive_skb(skb);
                        }
                }

                status = GRETH_BD_EN | GRETH_BD_IE;
                if (greth->rx_cur == GRETH_RXBD_NUM_MASK) {
                        status |= GRETH_BD_WR;
                }

                wmb();
                greth_write_bd(&bdp->stat, status);

                dma_sync_single_for_device(greth->dev, dma_addr, MAX_FRAME_SIZE, DMA_FROM_DEVICE);

                spin_lock_irqsave(&greth->devlock, flags); /* save from XMIT */
                greth_enable_rx(greth);
                spin_unlock_irqrestore(&greth->devlock, flags);

                greth->rx_cur = NEXT_RX(greth->rx_cur);
        }

        return count;
}

static inline int hw_checksummed(u32 status)
{

        if (status & GRETH_RXBD_IP_FRAG)
                return 0;

        if (status & GRETH_RXBD_IP && status & GRETH_RXBD_IP_CSERR)
                return 0;

        if (status & GRETH_RXBD_UDP && status & GRETH_RXBD_UDP_CSERR)
                return 0;

        if (status & GRETH_RXBD_TCP && status & GRETH_RXBD_TCP_CSERR)
                return 0;

        return 1;
}

static int greth_rx_gbit(struct net_device *dev, int limit)
{
        struct greth_private *greth;
        struct greth_bd *bdp;
        struct sk_buff *skb, *newskb;
        int pkt_len;
        int bad, count = 0;
        u32 status, dma_addr;
        unsigned long flags;

        greth = netdev_priv(dev);

        for (count = 0; count < limit; ++count) {

                bdp = greth->rx_bd_base + greth->rx_cur;
                skb = greth->rx_skbuff[greth->rx_cur];
                GRETH_REGSAVE(greth->regs->status, GRETH_INT_RE | GRETH_INT_RX);
                mb();
                status = greth_read_bd(&bdp->stat);
                bad = 0;

                if (status & GRETH_BD_EN)
                        break;

                /* Check status for errors. */
                if (unlikely(status & GRETH_RXBD_STATUS)) {

                        if (status & GRETH_RXBD_ERR_FT) {
                                dev->stats.rx_length_errors++;
                                bad = 1;
                        } else if (status &
                                   (GRETH_RXBD_ERR_AE | GRETH_RXBD_ERR_OE | GRETH_RXBD_ERR_LE)) {
                                dev->stats.rx_frame_errors++;
                                bad = 1;
                        } else if (status & GRETH_RXBD_ERR_CRC) {
                                dev->stats.rx_crc_errors++;
                                bad = 1;
                        }
                }

                /* Allocate new skb to replace current, not needed if the
                 * current skb can be reused */
                if (!bad && (newskb=netdev_alloc_skb(dev, MAX_FRAME_SIZE + NET_IP_ALIGN))) {
                        skb_reserve(newskb, NET_IP_ALIGN);

                        dma_addr = dma_map_single(greth->dev,
                                                      newskb->data,
                                                      MAX_FRAME_SIZE + NET_IP_ALIGN,
                                                      DMA_FROM_DEVICE);

                        if (!dma_mapping_error(greth->dev, dma_addr)) {
                                /* Process the incoming frame. */
                                pkt_len = status & GRETH_BD_LEN;

                                dma_unmap_single(greth->dev,
                                                 greth_read_bd(&bdp->addr),
                                                 MAX_FRAME_SIZE + NET_IP_ALIGN,
                                                 DMA_FROM_DEVICE);

                                if (netif_msg_pktdata(greth))
                                        greth_print_rx_packet(phys_to_virt(greth_read_bd(&bdp->addr)), pkt_len);

                                skb_put(skb, pkt_len);

                                if (dev->features & NETIF_F_RXCSUM && hw_checksummed(status))
                                        skb->ip_summed = CHECKSUM_UNNECESSARY;
                                else
                                        skb_checksum_none_assert(skb);

                                skb->protocol = eth_type_trans(skb, dev);
                                dev->stats.rx_packets++;
                                dev->stats.rx_bytes += pkt_len;
                                netif_receive_skb(skb);

                                greth->rx_skbuff[greth->rx_cur] = newskb;
                                greth_write_bd(&bdp->addr, dma_addr);
                        } else {
                                if (net_ratelimit())
                                        dev_warn(greth->dev, "Could not create DMA mapping, dropping packet\n");
                                dev_kfree_skb(newskb);
                                /* reusing current skb, so it is a drop */
                                dev->stats.rx_dropped++;
                        }
                } else if (bad) {
                        /* Bad Frame transfer, the skb is reused */
                        dev->stats.rx_dropped++;
                } else {
                        /* Failed Allocating a new skb. This is rather stupid
                         * but the current "filled" skb is reused, as if
                         * transfer failure. One could argue that RX descriptor
                         * table handling should be divided into cleaning and
                         * filling as the TX part of the driver
                         */
                        if (net_ratelimit())
                                dev_warn(greth->dev, "Could not allocate SKB, dropping packet\n");
                        /* reusing current skb, so it is a drop */
                        dev->stats.rx_dropped++;
                }

                status = GRETH_BD_EN | GRETH_BD_IE;
                if (greth->rx_cur == GRETH_RXBD_NUM_MASK) {
                        status |= GRETH_BD_WR;
                }

                wmb();
                greth_write_bd(&bdp->stat, status);
                spin_lock_irqsave(&greth->devlock, flags);
                greth_enable_rx(greth);
                spin_unlock_irqrestore(&greth->devlock, flags);
                greth->rx_cur = NEXT_RX(greth->rx_cur);
        }

        return count;

}

static int greth_poll(struct napi_struct *napi, int budget)
{
        struct greth_private *greth;
        int work_done = 0;
        unsigned long flags;
        u32 mask, ctrl;
        greth = container_of(napi, struct greth_private, napi);

restart_txrx_poll:
        if (greth->gbit_mac) {
                greth_clean_tx_gbit(greth->netdev);
                work_done += greth_rx_gbit(greth->netdev, budget - work_done);
        } else {
                if (netif_queue_stopped(greth->netdev))
                        greth_clean_tx(greth->netdev);
                work_done += greth_rx(greth->netdev, budget - work_done);
        }

        if (work_done < budget) {

                spin_lock_irqsave(&greth->devlock, flags);

                ctrl = GRETH_REGLOAD(greth->regs->control);
                if ((greth->gbit_mac && (greth->tx_last != greth->tx_next)) ||
                    (!greth->gbit_mac && netif_queue_stopped(greth->netdev))) {
                        GRETH_REGSAVE(greth->regs->control,
                                        ctrl | GRETH_TXI | GRETH_RXI);
                        mask = GRETH_INT_RX | GRETH_INT_RE |
                               GRETH_INT_TX | GRETH_INT_TE;
                } else {
                        GRETH_REGSAVE(greth->regs->control, ctrl | GRETH_RXI);
                        mask = GRETH_INT_RX | GRETH_INT_RE;
                }

                if (GRETH_REGLOAD(greth->regs->status) & mask) {
                        GRETH_REGSAVE(greth->regs->control, ctrl);
                        spin_unlock_irqrestore(&greth->devlock, flags);
                        goto restart_txrx_poll;
                } else {
                        napi_complete_done(napi, work_done);
                        spin_unlock_irqrestore(&greth->devlock, flags);
                }
        }

        return work_done;
}

static int greth_set_mac_add(struct net_device *dev, void *p)
{
        struct sockaddr *addr = p;
        struct greth_private *greth;
        struct greth_regs *regs;

        greth = netdev_priv(dev);
        regs = greth->regs;

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

        eth_hw_addr_set(dev, addr->sa_data);
        GRETH_REGSAVE(regs->esa_msb, dev->dev_addr[0] << 8 | dev->dev_addr[1]);
        GRETH_REGSAVE(regs->esa_lsb, dev->dev_addr[2] << 24 | dev->dev_addr[3] << 16 |
                      dev->dev_addr[4] << 8 | dev->dev_addr[5]);

        return 0;
}

static u32 greth_hash_get_index(__u8 *addr)
{
        return (ether_crc(6, addr)) & 0x3F;
}

static void greth_set_hash_filter(struct net_device *dev)
{
        struct netdev_hw_addr *ha;
        struct greth_private *greth = netdev_priv(dev);
        struct greth_regs *regs = greth->regs;
        u32 mc_filter[2];
        unsigned int bitnr;

        mc_filter[0] = mc_filter[1] = 0;

        netdev_for_each_mc_addr(ha, dev) {
                bitnr = greth_hash_get_index(ha->addr);
                mc_filter[bitnr >> 5] |= 1 << (bitnr & 31);
        }

        GRETH_REGSAVE(regs->hash_msb, mc_filter[1]);
        GRETH_REGSAVE(regs->hash_lsb, mc_filter[0]);
}

static void greth_set_multicast_list(struct net_device *dev)
{
        int cfg;
        struct greth_private *greth = netdev_priv(dev);
        struct greth_regs *regs = greth->regs;

        cfg = GRETH_REGLOAD(regs->control);
        if (dev->flags & IFF_PROMISC)
                cfg |= GRETH_CTRL_PR;
        else
                cfg &= ~GRETH_CTRL_PR;

        if (greth->multicast) {
                if (dev->flags & IFF_ALLMULTI) {
                        GRETH_REGSAVE(regs->hash_msb, -1);
                        GRETH_REGSAVE(regs->hash_lsb, -1);
                        cfg |= GRETH_CTRL_MCEN;
                        GRETH_REGSAVE(regs->control, cfg);
                        return;
                }

                if (netdev_mc_empty(dev)) {
                        cfg &= ~GRETH_CTRL_MCEN;
                        GRETH_REGSAVE(regs->control, cfg);
                        return;
                }

                /* Setup multicast filter */
                greth_set_hash_filter(dev);
                cfg |= GRETH_CTRL_MCEN;
        }
        GRETH_REGSAVE(regs->control, cfg);
}

static u32 greth_get_msglevel(struct net_device *dev)
{
        struct greth_private *greth = netdev_priv(dev);
        return greth->msg_enable;
}

static void greth_set_msglevel(struct net_device *dev, u32 value)
{
        struct greth_private *greth = netdev_priv(dev);
        greth->msg_enable = value;
}

static int greth_get_regs_len(struct net_device *dev)
{
        return sizeof(struct greth_regs);
}

static void greth_get_drvinfo(struct net_device *dev, struct ethtool_drvinfo *info)
{
        struct greth_private *greth = netdev_priv(dev);

        strscpy(info->driver, dev_driver_string(greth->dev),
                sizeof(info->driver));
        strscpy(info->bus_info, greth->dev->bus->name, sizeof(info->bus_info));
}

static void greth_get_regs(struct net_device *dev, struct ethtool_regs *regs, void *p)
{
        int i;
        struct greth_private *greth = netdev_priv(dev);
        u32 __iomem *greth_regs = (u32 __iomem *) greth->regs;
        u32 *buff = p;

        for (i = 0; i < sizeof(struct greth_regs) / sizeof(u32); i++)
                buff[i] = greth_read_bd(&greth_regs[i]);
}

static const struct ethtool_ops greth_ethtool_ops = {
        .get_msglevel           = greth_get_msglevel,
        .set_msglevel           = greth_set_msglevel,
        .get_drvinfo            = greth_get_drvinfo,
        .get_regs_len           = greth_get_regs_len,
        .get_regs               = greth_get_regs,
        .get_link               = ethtool_op_get_link,
        .get_link_ksettings     = phy_ethtool_get_link_ksettings,
        .set_link_ksettings     = phy_ethtool_set_link_ksettings,
};

static struct net_device_ops greth_netdev_ops = {
        .ndo_open               = greth_open,
        .ndo_stop               = greth_close,
        .ndo_start_xmit         = greth_start_xmit,
        .ndo_set_mac_address    = greth_set_mac_add,
        .ndo_validate_addr      = eth_validate_addr,
};

static inline int wait_for_mdio(struct greth_private *greth)
{
        unsigned long timeout = jiffies + 4*HZ/100;
        while (GRETH_REGLOAD(greth->regs->mdio) & GRETH_MII_BUSY) {
                if (time_after(jiffies, timeout))
                        return 0;
        }
        return 1;
}

static int greth_mdio_read(struct mii_bus *bus, int phy, int reg)
{
        struct greth_private *greth = bus->priv;
        int data;

        if (!wait_for_mdio(greth))
                return -EBUSY;

        GRETH_REGSAVE(greth->regs->mdio, ((phy & 0x1F) << 11) | ((reg & 0x1F) << 6) | 2);

        if (!wait_for_mdio(greth))
                return -EBUSY;

        if (!(GRETH_REGLOAD(greth->regs->mdio) & GRETH_MII_NVALID)) {
                data = (GRETH_REGLOAD(greth->regs->mdio) >> 16) & 0xFFFF;
                return data;

        } else {
                return -1;
        }
}

static int greth_mdio_write(struct mii_bus *bus, int phy, int reg, u16 val)
{
        struct greth_private *greth = bus->priv;

        if (!wait_for_mdio(greth))
                return -EBUSY;

        GRETH_REGSAVE(greth->regs->mdio,
                      ((val & 0xFFFF) << 16) | ((phy & 0x1F) << 11) | ((reg & 0x1F) << 6) | 1);

        if (!wait_for_mdio(greth))
                return -EBUSY;

        return 0;
}

static void greth_link_change(struct net_device *dev)
{
        struct greth_private *greth = netdev_priv(dev);
        struct phy_device *phydev = dev->phydev;
        unsigned long flags;
        int status_change = 0;
        u32 ctrl;

        spin_lock_irqsave(&greth->devlock, flags);

        if (phydev->link) {

                if ((greth->speed != phydev->speed) || (greth->duplex != phydev->duplex)) {
                        ctrl = GRETH_REGLOAD(greth->regs->control) &
                               ~(GRETH_CTRL_FD | GRETH_CTRL_SP | GRETH_CTRL_GB);

                        if (phydev->duplex)
                                ctrl |= GRETH_CTRL_FD;

                        if (phydev->speed == SPEED_100)
                                ctrl |= GRETH_CTRL_SP;
                        else if (phydev->speed == SPEED_1000)
                                ctrl |= GRETH_CTRL_GB;

                        GRETH_REGSAVE(greth->regs->control, ctrl);
                        greth->speed = phydev->speed;
                        greth->duplex = phydev->duplex;
                        status_change = 1;
                }
        }

        if (phydev->link != greth->link) {
                if (!phydev->link) {
                        greth->speed = 0;
                        greth->duplex = -1;
                }
                greth->link = phydev->link;

                status_change = 1;
        }

        spin_unlock_irqrestore(&greth->devlock, flags);

        if (status_change) {
                if (phydev->link)
                        pr_debug("%s: link up (%d/%s)\n",
                                dev->name, phydev->speed,
                                DUPLEX_FULL == phydev->duplex ? "Full" : "Half");
                else
                        pr_debug("%s: link down\n", dev->name);
        }
}

static int greth_mdio_probe(struct net_device *dev)
{
        struct greth_private *greth = netdev_priv(dev);
        struct phy_device *phy = NULL;
        int ret;

        /* Find the first PHY */
        phy = phy_find_first(greth->mdio);

        if (!phy) {
                if (netif_msg_probe(greth))
                        dev_err(&dev->dev, "no PHY found\n");
                return -ENXIO;
        }

        ret = phy_connect_direct(dev, phy, &greth_link_change,
                                 greth->gbit_mac ? PHY_INTERFACE_MODE_GMII : PHY_INTERFACE_MODE_MII);
        if (ret) {
                if (netif_msg_ifup(greth))
                        dev_err(&dev->dev, "could not attach to PHY\n");
                return ret;
        }

        if (greth->gbit_mac)
                phy_set_max_speed(phy, SPEED_1000);
        else
                phy_set_max_speed(phy, SPEED_100);

        linkmode_copy(phy->advertising, phy->supported);

        greth->link = 0;
        greth->speed = 0;
        greth->duplex = -1;

        return 0;
}

static int greth_mdio_init(struct greth_private *greth)
{
        int ret;
        unsigned long timeout;
        struct net_device *ndev = greth->netdev;

        greth->mdio = mdiobus_alloc();
        if (!greth->mdio) {
                return -ENOMEM;
        }

        greth->mdio->name = "greth-mdio";
        snprintf(greth->mdio->id, MII_BUS_ID_SIZE, "%s-%d", greth->mdio->name, greth->irq);
        greth->mdio->read = greth_mdio_read;
        greth->mdio->write = greth_mdio_write;
        greth->mdio->priv = greth;

        ret = mdiobus_register(greth->mdio);
        if (ret) {
                goto error;
        }

        ret = greth_mdio_probe(greth->netdev);
        if (ret) {
                if (netif_msg_probe(greth))
                        dev_err(&greth->netdev->dev, "failed to probe MDIO bus\n");
                goto unreg_mdio;
        }

        phy_start(ndev->phydev);

        /* If Ethernet debug link is used make autoneg happen right away */
        if (greth->edcl && greth_edcl == 1) {
                phy_start_aneg(ndev->phydev);
                timeout = jiffies + 6*HZ;
                while (!phy_aneg_done(ndev->phydev) &&
                       time_before(jiffies, timeout)) {
                }
                phy_read_status(ndev->phydev);
                greth_link_change(greth->netdev);
        }

        return 0;

unreg_mdio:
        mdiobus_unregister(greth->mdio);
error:
        mdiobus_free(greth->mdio);
        return ret;
}

/* Initialize the GRETH MAC */
static int greth_of_probe(struct platform_device *ofdev)
{
        struct net_device *dev;
        struct greth_private *greth;
        struct greth_regs *regs;

        int i;
        int err;
        int tmp;
        u8 addr[ETH_ALEN];
        unsigned long timeout;

        dev = alloc_etherdev(sizeof(struct greth_private));

        if (dev == NULL)
                return -ENOMEM;

        greth = netdev_priv(dev);
        greth->netdev = dev;
        greth->dev = &ofdev->dev;

        if (greth_debug > 0)
                greth->msg_enable = greth_debug;
        else
                greth->msg_enable = GRETH_DEF_MSG_ENABLE;

        spin_lock_init(&greth->devlock);

        greth->regs = of_ioremap(&ofdev->resource[0], 0,
                                 resource_size(&ofdev->resource[0]),
                                 "grlib-greth regs");

        if (greth->regs == NULL) {
                if (netif_msg_probe(greth))
                        dev_err(greth->dev, "ioremap failure.\n");
                err = -EIO;
                goto error1;
        }

        regs = greth->regs;
        greth->irq = ofdev->archdata.irqs[0];

        dev_set_drvdata(greth->dev, dev);
        SET_NETDEV_DEV(dev, greth->dev);

        if (netif_msg_probe(greth))
                dev_dbg(greth->dev, "resetting controller.\n");

        /* Reset the controller. */
        GRETH_REGSAVE(regs->control, GRETH_RESET);

        /* Wait for MAC to reset itself */
        timeout = jiffies + HZ/100;
        while (GRETH_REGLOAD(regs->control) & GRETH_RESET) {
                if (time_after(jiffies, timeout)) {
                        err = -EIO;
                        if (netif_msg_probe(greth))
                                dev_err(greth->dev, "timeout when waiting for reset.\n");
                        goto error2;
                }
        }

        /* Get default PHY address  */
        greth->phyaddr = (GRETH_REGLOAD(regs->mdio) >> 11) & 0x1F;

        /* Check if we have GBIT capable MAC */
        tmp = GRETH_REGLOAD(regs->control);
        greth->gbit_mac = (tmp >> 27) & 1;

        /* Check for multicast capability */
        greth->multicast = (tmp >> 25) & 1;

        greth->edcl = (tmp >> 31) & 1;

        /* If we have EDCL we disable the EDCL speed-duplex FSM so
         * it doesn't interfere with the software */
        if (greth->edcl != 0)
                GRETH_REGORIN(regs->control, GRETH_CTRL_DISDUPLEX);

        /* Check if MAC can handle MDIO interrupts */
        greth->mdio_int_en = (tmp >> 26) & 1;

        err = greth_mdio_init(greth);
        if (err) {
                if (netif_msg_probe(greth))
                        dev_err(greth->dev, "failed to register MDIO bus\n");
                goto error2;
        }

        /* Allocate TX descriptor ring in coherent memory */
        greth->tx_bd_base = dma_alloc_coherent(greth->dev, 1024,
                                               &greth->tx_bd_base_phys,
                                               GFP_KERNEL);
        if (!greth->tx_bd_base) {
                err = -ENOMEM;
                goto error3;
        }

        /* Allocate RX descriptor ring in coherent memory */
        greth->rx_bd_base = dma_alloc_coherent(greth->dev, 1024,
                                               &greth->rx_bd_base_phys,
                                               GFP_KERNEL);
        if (!greth->rx_bd_base) {
                err = -ENOMEM;
                goto error4;
        }

        /* Get MAC address from: module param, OF property or ID prom */
        for (i = 0; i < 6; i++) {
                if (macaddr[i] != 0)
                        break;
        }
        if (i == 6) {
                err = of_get_mac_address(ofdev->dev.of_node, addr);
                if (!err) {
                        for (i = 0; i < 6; i++)
                                macaddr[i] = (unsigned int) addr[i];
                } else {
#ifdef CONFIG_SPARC
                        for (i = 0; i < 6; i++)
                                macaddr[i] = (unsigned int) idprom->id_ethaddr[i];
#endif
                }
        }

        for (i = 0; i < 6; i++)
                addr[i] = macaddr[i];
        eth_hw_addr_set(dev, addr);

        macaddr[5]++;

        if (!is_valid_ether_addr(&dev->dev_addr[0])) {
                if (netif_msg_probe(greth))
                        dev_err(greth->dev, "no valid ethernet address, aborting.\n");
                err = -EINVAL;
                goto error5;
        }

        GRETH_REGSAVE(regs->esa_msb, dev->dev_addr[0] << 8 | dev->dev_addr[1]);
        GRETH_REGSAVE(regs->esa_lsb, dev->dev_addr[2] << 24 | dev->dev_addr[3] << 16 |
                      dev->dev_addr[4] << 8 | dev->dev_addr[5]);

        /* Clear all pending interrupts except PHY irq */
        GRETH_REGSAVE(regs->status, 0xFF);

        if (greth->gbit_mac) {
                dev->hw_features = NETIF_F_SG | NETIF_F_IP_CSUM |
                        NETIF_F_RXCSUM;
                dev->features = dev->hw_features | NETIF_F_HIGHDMA;
                greth_netdev_ops.ndo_start_xmit = greth_start_xmit_gbit;
        }

        if (greth->multicast) {
                greth_netdev_ops.ndo_set_rx_mode = greth_set_multicast_list;
                dev->flags |= IFF_MULTICAST;
        } else {
                dev->flags &= ~IFF_MULTICAST;
        }

        dev->netdev_ops = &greth_netdev_ops;
        dev->ethtool_ops = &greth_ethtool_ops;

        err = register_netdev(dev);
        if (err) {
                if (netif_msg_probe(greth))
                        dev_err(greth->dev, "netdevice registration failed.\n");
                goto error5;
        }

        /* setup NAPI */
        netif_napi_add(dev, &greth->napi, greth_poll);

        return 0;

error5:
        dma_free_coherent(greth->dev, 1024, greth->rx_bd_base, greth->rx_bd_base_phys);
error4:
        dma_free_coherent(greth->dev, 1024, greth->tx_bd_base, greth->tx_bd_base_phys);
error3:
        mdiobus_unregister(greth->mdio);
error2:
        of_iounmap(&ofdev->resource[0], greth->regs, resource_size(&ofdev->resource[0]));
error1:
        free_netdev(dev);
        return err;
}

static void greth_of_remove(struct platform_device *of_dev)
{
        struct net_device *ndev = platform_get_drvdata(of_dev);
        struct greth_private *greth = netdev_priv(ndev);

        /* Free descriptor areas */
        dma_free_coherent(&of_dev->dev, 1024, greth->rx_bd_base, greth->rx_bd_base_phys);

        dma_free_coherent(&of_dev->dev, 1024, greth->tx_bd_base, greth->tx_bd_base_phys);

        if (ndev->phydev)
                phy_stop(ndev->phydev);
        mdiobus_unregister(greth->mdio);

        unregister_netdev(ndev);

        of_iounmap(&of_dev->resource[0], greth->regs, resource_size(&of_dev->resource[0]));

        free_netdev(ndev);
}

static const struct of_device_id greth_of_match[] = {
        {
         .name = "GAISLER_ETHMAC",
         },
        {
         .name = "01_01d",
         },
        {},
};

MODULE_DEVICE_TABLE(of, greth_of_match);

static struct platform_driver greth_of_driver = {
        .driver = {
                .name = "grlib-greth",
                .of_match_table = greth_of_match,
        },
        .probe = greth_of_probe,
        .remove = greth_of_remove,
};

module_platform_driver(greth_of_driver);

MODULE_AUTHOR("Aeroflex Gaisler AB.");
MODULE_DESCRIPTION("Aeroflex Gaisler Ethernet MAC driver");
MODULE_LICENSE("GPL");