/*
 * Driver for Xilinx TEMAC Ethernet device
 *
 * Copyright (c) 2008 Nissin Systems Co., Ltd.,  Yoshio Kashiwagi
 * Copyright (c) 2005-2008 DLA Systems,  David H. Lynch Jr. <dhlii@dlasys.net>
 * Copyright (c) 2008-2009 Secret Lab Technologies Ltd.
 *
 * This is a driver for the Xilinx ll_temac ipcore which is often used
 * in the Virtex and Spartan series of chips.
 *
 * Notes:
 * - The ll_temac hardware uses indirect access for many of the TEMAC
 *   registers, include the MDIO bus.  However, indirect access to MDIO
 *   registers take considerably more clock cycles than to TEMAC registers.
 *   MDIO accesses are long, so threads doing them should probably sleep
 *   rather than busywait.  However, since only one indirect access can be
 *   in progress at any given time, that means that *all* indirect accesses
 *   could end up sleeping (to wait for an MDIO access to complete).
 *   Fortunately none of the indirect accesses are on the 'hot' path for tx
 *   or rx, so this should be okay.
 *
 * TODO:
 * - Fix driver to work on more than just Virtex5.  Right now the driver
 *   assumes that the locallink DMA registers are accessed via DCR
 *   instructions.
 * - Factor out locallink DMA code into separate driver
 * - Fix multicast assignment.
 * - Fix support for hardware checksumming.
 * - Testing.  Lots and lots of testing.
 *
 */

#include <linux/delay.h>
#include <linux/etherdevice.h>
#include <linux/init.h>
#include <linux/mii.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/netdevice.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_mdio.h>
#include <linux/of_platform.h>
#include <linux/skbuff.h>
#include <linux/spinlock.h>
#include <linux/tcp.h>      /* needed for sizeof(tcphdr) */
#include <linux/udp.h>      /* needed for sizeof(udphdr) */
#include <linux/phy.h>
#include <linux/in.h>
#include <linux/io.h>
#include <linux/ip.h>

#include "ll_temac.h"

#define TX_BD_NUM   64
#define RX_BD_NUM   128

/* ---------------------------------------------------------------------
 * Low level register access functions
 */

u32 temac_ior(struct temac_local *lp, int offset)
{
        return in_be32((u32 *)(lp->regs + offset));
}

void temac_iow(struct temac_local *lp, int offset, u32 value)
{
        out_be32((u32 *) (lp->regs + offset), value);
}

int temac_indirect_busywait(struct temac_local *lp)
{
        long end = jiffies + 2;

        while (!(temac_ior(lp, XTE_RDY0_OFFSET) & XTE_RDY0_HARD_ACS_RDY_MASK)) {
                if (end - jiffies <= 0) {
                        WARN_ON(1);
                        return -ETIMEDOUT;
                }
                msleep(1);
        }
        return 0;
}

/**
 * temac_indirect_in32
 *
 * lp->indirect_mutex must be held when calling this function
 */
u32 temac_indirect_in32(struct temac_local *lp, int reg)
{
        u32 val;

        if (temac_indirect_busywait(lp))
                return -ETIMEDOUT;
        temac_iow(lp, XTE_CTL0_OFFSET, reg);
        if (temac_indirect_busywait(lp))
                return -ETIMEDOUT;
        val = temac_ior(lp, XTE_LSW0_OFFSET);

        return val;
}

/**
 * temac_indirect_out32
 *
 * lp->indirect_mutex must be held when calling this function
 */
void temac_indirect_out32(struct temac_local *lp, int reg, u32 value)
{
        if (temac_indirect_busywait(lp))
                return;
        temac_iow(lp, XTE_LSW0_OFFSET, value);
        temac_iow(lp, XTE_CTL0_OFFSET, CNTLREG_WRITE_ENABLE_MASK | reg);
}

static u32 temac_dma_in32(struct temac_local *lp, int reg)
{
        return dcr_read(lp->sdma_dcrs, reg);
}

static void temac_dma_out32(struct temac_local *lp, int reg, u32 value)
{
        dcr_write(lp->sdma_dcrs, reg, value);
}

/**
 * temac_dma_bd_init - Setup buffer descriptor rings
 */
static int temac_dma_bd_init(struct net_device *ndev)
{
        struct temac_local *lp = netdev_priv(ndev);
        struct sk_buff *skb;
        int i;

        lp->rx_skb = kzalloc(sizeof(struct sk_buff)*RX_BD_NUM, GFP_KERNEL);
        /* allocate the tx and rx ring buffer descriptors. */
        /* returns a virtual addres and a physical address. */
        lp->tx_bd_v = dma_alloc_coherent(ndev->dev.parent,
                                         sizeof(*lp->tx_bd_v) * TX_BD_NUM,
                                         &lp->tx_bd_p, GFP_KERNEL);
        lp->rx_bd_v = dma_alloc_coherent(ndev->dev.parent,
                                         sizeof(*lp->rx_bd_v) * RX_BD_NUM,
                                         &lp->rx_bd_p, GFP_KERNEL);

        memset(lp->tx_bd_v, 0, sizeof(*lp->tx_bd_v) * TX_BD_NUM);
        for (i = 0; i < TX_BD_NUM; i++) {
                lp->tx_bd_v[i].next = lp->tx_bd_p +
                                sizeof(*lp->tx_bd_v) * ((i + 1) % TX_BD_NUM);
        }

        memset(lp->rx_bd_v, 0, sizeof(*lp->rx_bd_v) * RX_BD_NUM);
        for (i = 0; i < RX_BD_NUM; i++) {
                lp->rx_bd_v[i].next = lp->rx_bd_p +
                                sizeof(*lp->rx_bd_v) * ((i + 1) % RX_BD_NUM);

                skb = alloc_skb(XTE_MAX_JUMBO_FRAME_SIZE
                                + XTE_ALIGN, GFP_ATOMIC);
                if (skb == 0) {
                        dev_err(&ndev->dev, "alloc_skb error %d\n", i);
                        return -1;
                }
                lp->rx_skb[i] = skb;
                skb_reserve(skb,  BUFFER_ALIGN(skb->data));
                /* returns physical address of skb->data */
                lp->rx_bd_v[i].phys = dma_map_single(ndev->dev.parent,
                                                     skb->data,
                                                     XTE_MAX_JUMBO_FRAME_SIZE,
                                                     DMA_FROM_DEVICE);
                lp->rx_bd_v[i].len = XTE_MAX_JUMBO_FRAME_SIZE;
                lp->rx_bd_v[i].app0 = STS_CTRL_APP0_IRQONEND;
        }

        temac_dma_out32(lp, TX_CHNL_CTRL, 0x10220400 |
                                          CHNL_CTRL_IRQ_EN |
                                          CHNL_CTRL_IRQ_DLY_EN |
                                          CHNL_CTRL_IRQ_COAL_EN);
        /* 0x10220483 */
        /* 0x00100483 */
        temac_dma_out32(lp, RX_CHNL_CTRL, 0xff010000 |
                                          CHNL_CTRL_IRQ_EN |
                                          CHNL_CTRL_IRQ_DLY_EN |
                                          CHNL_CTRL_IRQ_COAL_EN |
                                          CHNL_CTRL_IRQ_IOE);
        /* 0xff010283 */

        temac_dma_out32(lp, RX_CURDESC_PTR,  lp->rx_bd_p);
        temac_dma_out32(lp, RX_TAILDESC_PTR,
                       lp->rx_bd_p + (sizeof(*lp->rx_bd_v) * (RX_BD_NUM - 1)));
        temac_dma_out32(lp, TX_CURDESC_PTR, lp->tx_bd_p);

        return 0;
}

/* ---------------------------------------------------------------------
 * net_device_ops
 */

static int temac_set_mac_address(struct net_device *ndev, void *address)
{
        struct temac_local *lp = netdev_priv(ndev);

        if (address)
                memcpy(ndev->dev_addr, address, ETH_ALEN);

        if (!is_valid_ether_addr(ndev->dev_addr))
                random_ether_addr(ndev->dev_addr);

        /* set up unicast MAC address filter set its mac address */
        mutex_lock(&lp->indirect_mutex);
        temac_indirect_out32(lp, XTE_UAW0_OFFSET,
                             (ndev->dev_addr[0]) |
                             (ndev->dev_addr[1] << 8) |
                             (ndev->dev_addr[2] << 16) |
                             (ndev->dev_addr[3] << 24));
        /* There are reserved bits in EUAW1
         * so don't affect them Set MAC bits [47:32] in EUAW1 */
        temac_indirect_out32(lp, XTE_UAW1_OFFSET,
                             (ndev->dev_addr[4] & 0x000000ff) |
                             (ndev->dev_addr[5] << 8));
        mutex_unlock(&lp->indirect_mutex);

        return 0;
}

static void temac_set_multicast_list(struct net_device *ndev)
{
        struct temac_local *lp = netdev_priv(ndev);
        u32 multi_addr_msw, multi_addr_lsw, val;
        int i;

        mutex_lock(&lp->indirect_mutex);
        if (ndev->flags & (IFF_ALLMULTI | IFF_PROMISC)
                        || ndev->mc_count > MULTICAST_CAM_TABLE_NUM) {
                /*
                 *      We must make the kernel realise we had to move
                 *      into promisc mode or we start all out war on
                 *      the cable. If it was a promisc request the
                 *      flag is already set. If not we assert it.
                 */
                ndev->flags |= IFF_PROMISC;
                temac_indirect_out32(lp, XTE_AFM_OFFSET, XTE_AFM_EPPRM_MASK);
                dev_info(&ndev->dev, "Promiscuous mode enabled.\n");
        } else if (ndev->mc_count) {
                struct dev_mc_list *mclist = ndev->mc_list;
                for (i = 0; mclist && i < ndev->mc_count; i++) {

                        if (i >= MULTICAST_CAM_TABLE_NUM)
                                break;
                        multi_addr_msw = ((mclist->dmi_addr[3] << 24) |
                                          (mclist->dmi_addr[2] << 16) |
                                          (mclist->dmi_addr[1] << 8) |
                                          (mclist->dmi_addr[0]));
                        temac_indirect_out32(lp, XTE_MAW0_OFFSET,
                                             multi_addr_msw);
                        multi_addr_lsw = ((mclist->dmi_addr[5] << 8) |
                                          (mclist->dmi_addr[4]) | (i << 16));
                        temac_indirect_out32(lp, XTE_MAW1_OFFSET,
                                             multi_addr_lsw);
                        mclist = mclist->next;
                }
        } else {
                val = temac_indirect_in32(lp, XTE_AFM_OFFSET);
                temac_indirect_out32(lp, XTE_AFM_OFFSET,
                                     val & ~XTE_AFM_EPPRM_MASK);
                temac_indirect_out32(lp, XTE_MAW0_OFFSET, 0);
                temac_indirect_out32(lp, XTE_MAW1_OFFSET, 0);
                dev_info(&ndev->dev, "Promiscuous mode disabled.\n");
        }
        mutex_unlock(&lp->indirect_mutex);
}

struct temac_option {
        int flg;
        u32 opt;
        u32 reg;
        u32 m_or;
        u32 m_and;
} temac_options[] = {
        /* Turn on jumbo packet support for both Rx and Tx */
        {
                .opt = XTE_OPTION_JUMBO,
                .reg = XTE_TXC_OFFSET,
                .m_or = XTE_TXC_TXJMBO_MASK,
        },
        {
                .opt = XTE_OPTION_JUMBO,
                .reg = XTE_RXC1_OFFSET,
                .m_or =XTE_RXC1_RXJMBO_MASK,
        },
        /* Turn on VLAN packet support for both Rx and Tx */
        {
                .opt = XTE_OPTION_VLAN,
                .reg = XTE_TXC_OFFSET,
                .m_or =XTE_TXC_TXVLAN_MASK,
        },
        {
                .opt = XTE_OPTION_VLAN,
                .reg = XTE_RXC1_OFFSET,
                .m_or =XTE_RXC1_RXVLAN_MASK,
        },
        /* Turn on FCS stripping on receive packets */
        {
                .opt = XTE_OPTION_FCS_STRIP,
                .reg = XTE_RXC1_OFFSET,
                .m_or =XTE_RXC1_RXFCS_MASK,
        },
        /* Turn on FCS insertion on transmit packets */
        {
                .opt = XTE_OPTION_FCS_INSERT,
                .reg = XTE_TXC_OFFSET,
                .m_or =XTE_TXC_TXFCS_MASK,
        },
        /* Turn on length/type field checking on receive packets */
        {
                .opt = XTE_OPTION_LENTYPE_ERR,
                .reg = XTE_RXC1_OFFSET,
                .m_or =XTE_RXC1_RXLT_MASK,
        },
        /* Turn on flow control */
        {
                .opt = XTE_OPTION_FLOW_CONTROL,
                .reg = XTE_FCC_OFFSET,
                .m_or =XTE_FCC_RXFLO_MASK,
        },
        /* Turn on flow control */
        {
                .opt = XTE_OPTION_FLOW_CONTROL,
                .reg = XTE_FCC_OFFSET,
                .m_or =XTE_FCC_TXFLO_MASK,
        },
        /* Turn on promiscuous frame filtering (all frames are received ) */
        {
                .opt = XTE_OPTION_PROMISC,
                .reg = XTE_AFM_OFFSET,
                .m_or =XTE_AFM_EPPRM_MASK,
        },
        /* Enable transmitter if not already enabled */
        {
                .opt = XTE_OPTION_TXEN,
                .reg = XTE_TXC_OFFSET,
                .m_or =XTE_TXC_TXEN_MASK,
        },
        /* Enable receiver? */
        {
                .opt = XTE_OPTION_RXEN,
                .reg = XTE_RXC1_OFFSET,
                .m_or =XTE_RXC1_RXEN_MASK,
        },
        {}
};

/**
 * temac_setoptions
 */
static u32 temac_setoptions(struct net_device *ndev, u32 options)
{
        struct temac_local *lp = netdev_priv(ndev);
        struct temac_option *tp = &temac_options[0];
        int reg;

        mutex_lock(&lp->indirect_mutex);
        while (tp->opt) {
                reg = temac_indirect_in32(lp, tp->reg) & ~tp->m_or;
                if (options & tp->opt)
                        reg |= tp->m_or;
                temac_indirect_out32(lp, tp->reg, reg);
                tp++;
        }
        lp->options |= options;
        mutex_unlock(&lp->indirect_mutex);

        return (0);
}

/* Initilize temac */
static void temac_device_reset(struct net_device *ndev)
{
        struct temac_local *lp = netdev_priv(ndev);
        u32 timeout;
        u32 val;

        /* Perform a software reset */

        /* 0x300 host enable bit ? */
        /* reset PHY through control register ?:1 */

        dev_dbg(&ndev->dev, "%s()\n", __func__);

        mutex_lock(&lp->indirect_mutex);
        /* Reset the receiver and wait for it to finish reset */
        temac_indirect_out32(lp, XTE_RXC1_OFFSET, XTE_RXC1_RXRST_MASK);
        timeout = 1000;
        while (temac_indirect_in32(lp, XTE_RXC1_OFFSET) & XTE_RXC1_RXRST_MASK) {
                udelay(1);
                if (--timeout == 0) {
                        dev_err(&ndev->dev,
                                "temac_device_reset RX reset timeout!!\n");
                        break;
                }
        }

        /* Reset the transmitter and wait for it to finish reset */
        temac_indirect_out32(lp, XTE_TXC_OFFSET, XTE_TXC_TXRST_MASK);
        timeout = 1000;
        while (temac_indirect_in32(lp, XTE_TXC_OFFSET) & XTE_TXC_TXRST_MASK) {
                udelay(1);
                if (--timeout == 0) {
                        dev_err(&ndev->dev,
                                "temac_device_reset TX reset timeout!!\n");
                        break;
                }
        }

        /* Disable the receiver */
        val = temac_indirect_in32(lp, XTE_RXC1_OFFSET);
        temac_indirect_out32(lp, XTE_RXC1_OFFSET, val & ~XTE_RXC1_RXEN_MASK);

        /* Reset Local Link (DMA) */
        temac_dma_out32(lp, DMA_CONTROL_REG, DMA_CONTROL_RST);
        timeout = 1000;
        while (temac_dma_in32(lp, DMA_CONTROL_REG) & DMA_CONTROL_RST) {
                udelay(1);
                if (--timeout == 0) {
                        dev_err(&ndev->dev,
                                "temac_device_reset DMA reset timeout!!\n");
                        break;
                }
        }
        temac_dma_out32(lp, DMA_CONTROL_REG, DMA_TAIL_ENABLE);

        temac_dma_bd_init(ndev);

        temac_indirect_out32(lp, XTE_RXC0_OFFSET, 0);
        temac_indirect_out32(lp, XTE_RXC1_OFFSET, 0);
        temac_indirect_out32(lp, XTE_TXC_OFFSET, 0);
        temac_indirect_out32(lp, XTE_FCC_OFFSET, XTE_FCC_RXFLO_MASK);

        mutex_unlock(&lp->indirect_mutex);

        /* Sync default options with HW
         * but leave receiver and transmitter disabled.  */
        temac_setoptions(ndev,
                         lp->options & ~(XTE_OPTION_TXEN | XTE_OPTION_RXEN));

        temac_set_mac_address(ndev, NULL);

        /* Set address filter table */
        temac_set_multicast_list(ndev);
        if (temac_setoptions(ndev, lp->options))
                dev_err(&ndev->dev, "Error setting TEMAC options\n");

        /* Init Driver variable */
        ndev->trans_start = 0;
}

void temac_adjust_link(struct net_device *ndev)
{
        struct temac_local *lp = netdev_priv(ndev);
        struct phy_device *phy = lp->phy_dev;
        u32 mii_speed;
        int link_state;

        /* hash together the state values to decide if something has changed */
        link_state = phy->speed | (phy->duplex << 1) | phy->link;

        mutex_lock(&lp->indirect_mutex);
        if (lp->last_link != link_state) {
                mii_speed = temac_indirect_in32(lp, XTE_EMCFG_OFFSET);
                mii_speed &= ~XTE_EMCFG_LINKSPD_MASK;

                switch (phy->speed) {
                case SPEED_1000: mii_speed |= XTE_EMCFG_LINKSPD_1000; break;
                case SPEED_100: mii_speed |= XTE_EMCFG_LINKSPD_100; break;
                case SPEED_10: mii_speed |= XTE_EMCFG_LINKSPD_10; break;
                }

                /* Write new speed setting out to TEMAC */
                temac_indirect_out32(lp, XTE_EMCFG_OFFSET, mii_speed);
                lp->last_link = link_state;
                phy_print_status(phy);
        }
        mutex_unlock(&lp->indirect_mutex);
}

static void temac_start_xmit_done(struct net_device *ndev)
{
        struct temac_local *lp = netdev_priv(ndev);
        struct cdmac_bd *cur_p;
        unsigned int stat = 0;

        cur_p = &lp->tx_bd_v[lp->tx_bd_ci];
        stat = cur_p->app0;

        while (stat & STS_CTRL_APP0_CMPLT) {
                dma_unmap_single(ndev->dev.parent, cur_p->phys, cur_p->len,
                                 DMA_TO_DEVICE);
                if (cur_p->app4)
                        dev_kfree_skb_irq((struct sk_buff *)cur_p->app4);
                cur_p->app0 = 0;

                ndev->stats.tx_packets++;
                ndev->stats.tx_bytes += cur_p->len;

                lp->tx_bd_ci++;
                if (lp->tx_bd_ci >= TX_BD_NUM)
                        lp->tx_bd_ci = 0;

                cur_p = &lp->tx_bd_v[lp->tx_bd_ci];
                stat = cur_p->app0;
        }

        netif_wake_queue(ndev);
}

static int temac_start_xmit(struct sk_buff *skb, struct net_device *ndev)
{
        struct temac_local *lp = netdev_priv(ndev);
        struct cdmac_bd *cur_p;
        dma_addr_t start_p, tail_p;
        int ii;
        unsigned long num_frag;
        skb_frag_t *frag;

        num_frag = skb_shinfo(skb)->nr_frags;
        frag = &skb_shinfo(skb)->frags[0];
        start_p = lp->tx_bd_p + sizeof(*lp->tx_bd_v) * lp->tx_bd_tail;
        cur_p = &lp->tx_bd_v[lp->tx_bd_tail];

        if (cur_p->app0 & STS_CTRL_APP0_CMPLT) {
                if (!netif_queue_stopped(ndev)) {
                        netif_stop_queue(ndev);
                        return NETDEV_TX_BUSY;
                }
                return NETDEV_TX_BUSY;
        }

        cur_p->app0 = 0;
        if (skb->ip_summed == CHECKSUM_PARTIAL) {
                const struct iphdr *ip = ip_hdr(skb);
                int length = 0, start = 0, insert = 0;

                switch (ip->protocol) {
                case IPPROTO_TCP:
                        start = sizeof(struct iphdr) + ETH_HLEN;
                        insert = sizeof(struct iphdr) + ETH_HLEN + 16;
                        length = ip->tot_len - sizeof(struct iphdr);
                        break;
                case IPPROTO_UDP:
                        start = sizeof(struct iphdr) + ETH_HLEN;
                        insert = sizeof(struct iphdr) + ETH_HLEN + 6;
                        length = ip->tot_len - sizeof(struct iphdr);
                        break;
                default:
                        break;
                }
                cur_p->app1 = ((start << 16) | insert);
                cur_p->app2 = csum_tcpudp_magic(ip->saddr, ip->daddr,
                                                length, ip->protocol, 0);
                skb->data[insert] = 0;
                skb->data[insert + 1] = 0;
        }
        cur_p->app0 |= STS_CTRL_APP0_SOP;
        cur_p->len = skb_headlen(skb);
        cur_p->phys = dma_map_single(ndev->dev.parent, skb->data, skb->len,
                                     DMA_TO_DEVICE);
        cur_p->app4 = (unsigned long)skb;

        for (ii = 0; ii < num_frag; ii++) {
                lp->tx_bd_tail++;
                if (lp->tx_bd_tail >= TX_BD_NUM)
                        lp->tx_bd_tail = 0;

                cur_p = &lp->tx_bd_v[lp->tx_bd_tail];
                cur_p->phys = dma_map_single(ndev->dev.parent,
                                             (void *)page_address(frag->page) +
                                                  frag->page_offset,
                                             frag->size, DMA_TO_DEVICE);
                cur_p->len = frag->size;
                cur_p->app0 = 0;
                frag++;
        }
        cur_p->app0 |= STS_CTRL_APP0_EOP;

        tail_p = lp->tx_bd_p + sizeof(*lp->tx_bd_v) * lp->tx_bd_tail;
        lp->tx_bd_tail++;
        if (lp->tx_bd_tail >= TX_BD_NUM)
                lp->tx_bd_tail = 0;

        /* Kick off the transfer */
        temac_dma_out32(lp, TX_TAILDESC_PTR, tail_p); /* DMA start */

        return NETDEV_TX_OK;
}


static void ll_temac_recv(struct net_device *ndev)
{
        struct temac_local *lp = netdev_priv(ndev);
        struct sk_buff *skb, *new_skb;
        unsigned int bdstat;
        struct cdmac_bd *cur_p;
        dma_addr_t tail_p;
        int length;
        unsigned long skb_vaddr;
        unsigned long flags;

        spin_lock_irqsave(&lp->rx_lock, flags);

        tail_p = lp->rx_bd_p + sizeof(*lp->rx_bd_v) * lp->rx_bd_ci;
        cur_p = &lp->rx_bd_v[lp->rx_bd_ci];

        bdstat = cur_p->app0;
        while ((bdstat & STS_CTRL_APP0_CMPLT)) {

                skb = lp->rx_skb[lp->rx_bd_ci];
                length = cur_p->app4;

                skb_vaddr = virt_to_bus(skb->data);
                dma_unmap_single(ndev->dev.parent, skb_vaddr, length,
                                 DMA_FROM_DEVICE);

                skb_put(skb, length);
                skb->dev = ndev;
                skb->protocol = eth_type_trans(skb, ndev);
                skb->ip_summed = CHECKSUM_NONE;

                netif_rx(skb);

                ndev->stats.rx_packets++;
                ndev->stats.rx_bytes += length;

                new_skb = alloc_skb(XTE_MAX_JUMBO_FRAME_SIZE + XTE_ALIGN,
                                GFP_ATOMIC);
                if (new_skb == 0) {
                        dev_err(&ndev->dev, "no memory for new sk_buff\n");
                        spin_unlock_irqrestore(&lp->rx_lock, flags);
                        return;
                }

                skb_reserve(new_skb, BUFFER_ALIGN(new_skb->data));

                cur_p->app0 = STS_CTRL_APP0_IRQONEND;
                cur_p->phys = dma_map_single(ndev->dev.parent, new_skb->data,
                                             XTE_MAX_JUMBO_FRAME_SIZE,
                                             DMA_FROM_DEVICE);
                cur_p->len = XTE_MAX_JUMBO_FRAME_SIZE;
                lp->rx_skb[lp->rx_bd_ci] = new_skb;

                lp->rx_bd_ci++;
                if (lp->rx_bd_ci >= RX_BD_NUM)
                        lp->rx_bd_ci = 0;

                cur_p = &lp->rx_bd_v[lp->rx_bd_ci];
                bdstat = cur_p->app0;
        }
        temac_dma_out32(lp, RX_TAILDESC_PTR, tail_p);

        spin_unlock_irqrestore(&lp->rx_lock, flags);
}

static irqreturn_t ll_temac_tx_irq(int irq, void *_ndev)
{
        struct net_device *ndev = _ndev;
        struct temac_local *lp = netdev_priv(ndev);
        unsigned int status;

        status = temac_dma_in32(lp, TX_IRQ_REG);
        temac_dma_out32(lp, TX_IRQ_REG, status);

        if (status & (IRQ_COAL | IRQ_DLY))
                temac_start_xmit_done(lp->ndev);
        if (status & 0x080)
                dev_err(&ndev->dev, "DMA error 0x%x\n", status);

        return IRQ_HANDLED;
}

static irqreturn_t ll_temac_rx_irq(int irq, void *_ndev)
{
        struct net_device *ndev = _ndev;
        struct temac_local *lp = netdev_priv(ndev);
        unsigned int status;

        /* Read and clear the status registers */
        status = temac_dma_in32(lp, RX_IRQ_REG);
        temac_dma_out32(lp, RX_IRQ_REG, status);

        if (status & (IRQ_COAL | IRQ_DLY))
                ll_temac_recv(lp->ndev);

        return IRQ_HANDLED;
}

static int temac_open(struct net_device *ndev)
{
        struct temac_local *lp = netdev_priv(ndev);
        int rc;

        dev_dbg(&ndev->dev, "temac_open()\n");

        if (lp->phy_node) {
                lp->phy_dev = of_phy_connect(lp->ndev, lp->phy_node,
                                             temac_adjust_link, 0, 0);
                if (!lp->phy_dev) {
                        dev_err(lp->dev, "of_phy_connect() failed\n");
                        return -ENODEV;
                }

                phy_start(lp->phy_dev);
        }

        rc = request_irq(lp->tx_irq, ll_temac_tx_irq, 0, ndev->name, ndev);
        if (rc)
                goto err_tx_irq;
        rc = request_irq(lp->rx_irq, ll_temac_rx_irq, 0, ndev->name, ndev);
        if (rc)
                goto err_rx_irq;

        temac_device_reset(ndev);
        return 0;

 err_rx_irq:
        free_irq(lp->tx_irq, ndev);
 err_tx_irq:
        if (lp->phy_dev)
                phy_disconnect(lp->phy_dev);
        lp->phy_dev = NULL;
        dev_err(lp->dev, "request_irq() failed\n");
        return rc;
}

static int temac_stop(struct net_device *ndev)
{
        struct temac_local *lp = netdev_priv(ndev);

        dev_dbg(&ndev->dev, "temac_close()\n");

        free_irq(lp->tx_irq, ndev);
        free_irq(lp->rx_irq, ndev);

        if (lp->phy_dev)
                phy_disconnect(lp->phy_dev);
        lp->phy_dev = NULL;

        return 0;
}

#ifdef CONFIG_NET_POLL_CONTROLLER
static void
temac_poll_controller(struct net_device *ndev)
{
        struct temac_local *lp = netdev_priv(ndev);

        disable_irq(lp->tx_irq);
        disable_irq(lp->rx_irq);

        ll_temac_rx_irq(lp->tx_irq, lp);
        ll_temac_tx_irq(lp->rx_irq, lp);

        enable_irq(lp->tx_irq);
        enable_irq(lp->rx_irq);
}
#endif

static const struct net_device_ops temac_netdev_ops = {
        .ndo_open = temac_open,
        .ndo_stop = temac_stop,
        .ndo_start_xmit = temac_start_xmit,
        .ndo_set_mac_address = temac_set_mac_address,
        //.ndo_set_multicast_list = temac_set_multicast_list,
#ifdef CONFIG_NET_POLL_CONTROLLER
        .ndo_poll_controller = temac_poll_controller,
#endif
};

/* ---------------------------------------------------------------------
 * SYSFS device attributes
 */
static ssize_t temac_show_llink_regs(struct device *dev,
                                     struct device_attribute *attr, char *buf)
{
        struct net_device *ndev = dev_get_drvdata(dev);
        struct temac_local *lp = netdev_priv(ndev);
        int i, len = 0;

        for (i = 0; i < 0x11; i++)
                len += sprintf(buf + len, "%.8x%s", temac_dma_in32(lp, i),
                               (i % 8) == 7 ? "\n" : " ");
        len += sprintf(buf + len, "\n");

        return len;
}

static DEVICE_ATTR(llink_regs, 0440, temac_show_llink_regs, NULL);

static struct attribute *temac_device_attrs[] = {
        &dev_attr_llink_regs.attr,
        NULL,
};

static const struct attribute_group temac_attr_group = {
        .attrs = temac_device_attrs,
};

static int __init
temac_of_probe(struct of_device *op, const struct of_device_id *match)
{
        struct device_node *np;
        struct temac_local *lp;
        struct net_device *ndev;
        const void *addr;
        int size, rc = 0;
        unsigned int dcrs;

        /* Init network device structure */
        ndev = alloc_etherdev(sizeof(*lp));
        if (!ndev) {
                dev_err(&op->dev, "could not allocate device.\n");
                return -ENOMEM;
        }
        ether_setup(ndev);
        dev_set_drvdata(&op->dev, ndev);
        SET_NETDEV_DEV(ndev, &op->dev);
        ndev->flags &= ~IFF_MULTICAST;  /* clear multicast */
        ndev->features = NETIF_F_SG | NETIF_F_FRAGLIST;
        ndev->netdev_ops = &temac_netdev_ops;
#if 0
        ndev->features |= NETIF_F_IP_CSUM; /* Can checksum TCP/UDP over IPv4. */
        ndev->features |= NETIF_F_HW_CSUM; /* Can checksum all the packets. */
        ndev->features |= NETIF_F_IPV6_CSUM; /* Can checksum IPV6 TCP/UDP */
        ndev->features |= NETIF_F_HIGHDMA; /* Can DMA to high memory. */
        ndev->features |= NETIF_F_HW_VLAN_TX; /* Transmit VLAN hw accel */
        ndev->features |= NETIF_F_HW_VLAN_RX; /* Receive VLAN hw acceleration */
        ndev->features |= NETIF_F_HW_VLAN_FILTER; /* Receive VLAN filtering */
        ndev->features |= NETIF_F_VLAN_CHALLENGED; /* cannot handle VLAN pkts */
        ndev->features |= NETIF_F_GSO; /* Enable software GSO. */
        ndev->features |= NETIF_F_MULTI_QUEUE; /* Has multiple TX/RX queues */
        ndev->features |= NETIF_F_LRO; /* large receive offload */
#endif

        /* setup temac private info structure */
        lp = netdev_priv(ndev);
        lp->ndev = ndev;
        lp->dev = &op->dev;
        lp->options = XTE_OPTION_DEFAULTS;
        spin_lock_init(&lp->rx_lock);
        mutex_init(&lp->indirect_mutex);

        /* map device registers */
        lp->regs = of_iomap(op->node, 0);
        if (!lp->regs) {
                dev_err(&op->dev, "could not map temac regs.\n");
                goto nodev;
        }

        /* Find the DMA node, map the DMA registers, and decode the DMA IRQs */
        np = of_parse_phandle(op->node, "llink-connected", 0);
        if (!np) {
                dev_err(&op->dev, "could not find DMA node\n");
                goto nodev;
        }

        dcrs = dcr_resource_start(np, 0);
        if (dcrs == 0) {
                dev_err(&op->dev, "could not get DMA register address\n");
                goto nodev;
        }
        lp->sdma_dcrs = dcr_map(np, dcrs, dcr_resource_len(np, 0));
        dev_dbg(&op->dev, "DCR base: %x\n", dcrs);

        lp->rx_irq = irq_of_parse_and_map(np, 0);
        lp->tx_irq = irq_of_parse_and_map(np, 1);
        if (!lp->rx_irq || !lp->tx_irq) {
                dev_err(&op->dev, "could not determine irqs\n");
                rc = -ENOMEM;
                goto nodev;
        }

        of_node_put(np); /* Finished with the DMA node; drop the reference */

        /* Retrieve the MAC address */
        addr = of_get_property(op->node, "local-mac-address", &size);
        if ((!addr) || (size != 6)) {
                dev_err(&op->dev, "could not find MAC address\n");
                rc = -ENODEV;
                goto nodev;
        }
        temac_set_mac_address(ndev, (void *)addr);

        rc = temac_mdio_setup(lp, op->node);
        if (rc)
                dev_warn(&op->dev, "error registering MDIO bus\n");

        lp->phy_node = of_parse_phandle(op->node, "phy-handle", 0);
        if (lp->phy_node)
                dev_dbg(lp->dev, "using PHY node %s (%p)\n", np->full_name, np);

        /* Add the device attributes */
        rc = sysfs_create_group(&lp->dev->kobj, &temac_attr_group);
        if (rc) {
                dev_err(lp->dev, "Error creating sysfs files\n");
                goto nodev;
        }

        rc = register_netdev(lp->ndev);
        if (rc) {
                dev_err(lp->dev, "register_netdev() error (%i)\n", rc);
                goto err_register_ndev;
        }

        return 0;

 err_register_ndev:
        sysfs_remove_group(&lp->dev->kobj, &temac_attr_group);
 nodev:
        free_netdev(ndev);
        ndev = NULL;
        return rc;
}

static int __devexit temac_of_remove(struct of_device *op)
{
        struct net_device *ndev = dev_get_drvdata(&op->dev);
        struct temac_local *lp = netdev_priv(ndev);

        temac_mdio_teardown(lp);
        unregister_netdev(ndev);
        sysfs_remove_group(&lp->dev->kobj, &temac_attr_group);
        if (lp->phy_node)
                of_node_put(lp->phy_node);
        lp->phy_node = NULL;
        dev_set_drvdata(&op->dev, NULL);
        free_netdev(ndev);
        return 0;
}

static struct of_device_id temac_of_match[] __devinitdata = {
        { .compatible = "xlnx,xps-ll-temac-1.01.b", },
        {},
};
MODULE_DEVICE_TABLE(of, temac_of_match);

static struct of_platform_driver temac_of_driver = {
        .match_table = temac_of_match,
        .probe = temac_of_probe,
        .remove = __devexit_p(temac_of_remove),
        .driver = {
                .owner = THIS_MODULE,
                .name = "xilinx_temac",
        },
};

static int __init temac_init(void)
{
        return of_register_platform_driver(&temac_of_driver);
}
module_init(temac_init);

static void __exit temac_exit(void)
{
        of_unregister_platform_driver(&temac_of_driver);
}
module_exit(temac_exit);

MODULE_DESCRIPTION("Xilinx LL_TEMAC Ethernet driver");
MODULE_AUTHOR("Yoshio Kashiwagi");
MODULE_LICENSE("GPL");