// SPDX-License-Identifier: GPL-2.0-only
/*
 * 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:
 * - Factor out locallink DMA code into separate driver
 * - Fix support for hardware checksumming.
 * - Testing.  Lots and lots of testing.
 *
 */

#include <linux/delay.h>
#include <linux/etherdevice.h>
#include <linux/mii.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/netdevice.h>
#include <linux/if_ether.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_irq.h>
#include <linux/of_mdio.h>
#include <linux/of_net.h>
#include <linux/of_platform.h>
#include <linux/of_address.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 <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/workqueue.h>
#include <linux/dma-mapping.h>
#include <linux/processor.h>
#include <linux/platform_data/xilinx-ll-temac.h>

#include "ll_temac.h"

/* Descriptors defines for Tx and Rx DMA */
#define TX_BD_NUM_DEFAULT               64
#define RX_BD_NUM_DEFAULT               1024
#define TX_BD_NUM_MAX                   4096
#define RX_BD_NUM_MAX                   4096

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

static u32 _temac_ior_be(struct temac_local *lp, int offset)
{
        return ioread32be(lp->regs + offset);
}

static void _temac_iow_be(struct temac_local *lp, int offset, u32 value)
{
        return iowrite32be(value, lp->regs + offset);
}

static u32 _temac_ior_le(struct temac_local *lp, int offset)
{
        return ioread32(lp->regs + offset);
}

static void _temac_iow_le(struct temac_local *lp, int offset, u32 value)
{
        return iowrite32(value, lp->regs + offset);
}

static bool hard_acs_rdy(struct temac_local *lp)
{
        return temac_ior(lp, XTE_RDY0_OFFSET) & XTE_RDY0_HARD_ACS_RDY_MASK;
}

static bool hard_acs_rdy_or_timeout(struct temac_local *lp, ktime_t timeout)
{
        ktime_t cur = ktime_get();

        return hard_acs_rdy(lp) || ktime_after(cur, timeout);
}

/* Poll for maximum 20 ms.  This is similar to the 2 jiffies @ 100 Hz
 * that was used before, and should cover MDIO bus speed down to 3200
 * Hz.
 */
#define HARD_ACS_RDY_POLL_NS (20 * NSEC_PER_MSEC)

/*
 * temac_indirect_busywait - Wait for current indirect register access
 * to complete.
 */
int temac_indirect_busywait(struct temac_local *lp)
{
        ktime_t timeout = ktime_add_ns(ktime_get(), HARD_ACS_RDY_POLL_NS);

        spin_until_cond(hard_acs_rdy_or_timeout(lp, timeout));
        if (WARN_ON(!hard_acs_rdy(lp)))
                return -ETIMEDOUT;
        else
                return 0;
}

/*
 * temac_indirect_in32 - Indirect register read access.  This function
 * must be called without lp->indirect_lock being held.
 */
u32 temac_indirect_in32(struct temac_local *lp, int reg)
{
        unsigned long flags;
        int val;

        spin_lock_irqsave(lp->indirect_lock, flags);
        val = temac_indirect_in32_locked(lp, reg);
        spin_unlock_irqrestore(lp->indirect_lock, flags);
        return val;
}

/*
 * temac_indirect_in32_locked - Indirect register read access.  This
 * function must be called with lp->indirect_lock being held.  Use
 * this together with spin_lock_irqsave/spin_lock_irqrestore to avoid
 * repeated lock/unlock and to ensure uninterrupted access to indirect
 * registers.
 */
u32 temac_indirect_in32_locked(struct temac_local *lp, int reg)
{
        /* This initial wait should normally not spin, as we always
         * try to wait for indirect access to complete before
         * releasing the indirect_lock.
         */
        if (WARN_ON(temac_indirect_busywait(lp)))
                return -ETIMEDOUT;
        /* Initiate read from indirect register */
        temac_iow(lp, XTE_CTL0_OFFSET, reg);
        /* Wait for indirect register access to complete.  We really
         * should not see timeouts, and could even end up causing
         * problem for following indirect access, so let's make a bit
         * of WARN noise.
         */
        if (WARN_ON(temac_indirect_busywait(lp)))
                return -ETIMEDOUT;
        /* Value is ready now */
        return temac_ior(lp, XTE_LSW0_OFFSET);
}

/*
 * temac_indirect_out32 - Indirect register write access.  This function
 * must be called without lp->indirect_lock being held.
 */
void temac_indirect_out32(struct temac_local *lp, int reg, u32 value)
{
        unsigned long flags;

        spin_lock_irqsave(lp->indirect_lock, flags);
        temac_indirect_out32_locked(lp, reg, value);
        spin_unlock_irqrestore(lp->indirect_lock, flags);
}

/*
 * temac_indirect_out32_locked - Indirect register write access.  This
 * function must be called with lp->indirect_lock being held.  Use
 * this together with spin_lock_irqsave/spin_lock_irqrestore to avoid
 * repeated lock/unlock and to ensure uninterrupted access to indirect
 * registers.
 */
void temac_indirect_out32_locked(struct temac_local *lp, int reg, u32 value)
{
        /* As in temac_indirect_in32_locked(), we should normally not
         * spin here.  And if it happens, we actually end up silently
         * ignoring the write request.  Ouch.
         */
        if (WARN_ON(temac_indirect_busywait(lp)))
                return;
        /* Initiate write to indirect register */
        temac_iow(lp, XTE_LSW0_OFFSET, value);
        temac_iow(lp, XTE_CTL0_OFFSET, CNTLREG_WRITE_ENABLE_MASK | reg);
        /* As in temac_indirect_in32_locked(), we should not see timeouts
         * here.  And if it happens, we continue before the write has
         * completed.  Not good.
         */
        WARN_ON(temac_indirect_busywait(lp));
}

/*
 * temac_dma_in32_* - Memory mapped DMA read, these function expects a
 * register input that is based on DCR word addresses which are then
 * converted to memory mapped byte addresses.  To be assigned to
 * lp->dma_in32.
 */
static u32 temac_dma_in32_be(struct temac_local *lp, int reg)
{
        return ioread32be(lp->sdma_regs + (reg << 2));
}

static u32 temac_dma_in32_le(struct temac_local *lp, int reg)
{
        return ioread32(lp->sdma_regs + (reg << 2));
}

/*
 * temac_dma_out32_* - Memory mapped DMA read, these function expects
 * a register input that is based on DCR word addresses which are then
 * converted to memory mapped byte addresses.  To be assigned to
 * lp->dma_out32.
 */
static void temac_dma_out32_be(struct temac_local *lp, int reg, u32 value)
{
        iowrite32be(value, lp->sdma_regs + (reg << 2));
}

static void temac_dma_out32_le(struct temac_local *lp, int reg, u32 value)
{
        iowrite32(value, lp->sdma_regs + (reg << 2));
}

/* DMA register access functions can be DCR based or memory mapped.
 * The PowerPC 440 is DCR based, the PowerPC 405 and MicroBlaze are both
 * memory mapped.
 */
#ifdef CONFIG_PPC_DCR

/*
 * temac_dma_dcr_in32 - DCR based DMA read
 */
static u32 temac_dma_dcr_in(struct temac_local *lp, int reg)
{
        return dcr_read(lp->sdma_dcrs, reg);
}

/*
 * temac_dma_dcr_out32 - DCR based DMA write
 */
static void temac_dma_dcr_out(struct temac_local *lp, int reg, u32 value)
{
        dcr_write(lp->sdma_dcrs, reg, value);
}

/*
 * temac_dcr_setup - If the DMA is DCR based, then setup the address and
 * I/O  functions
 */
static int temac_dcr_setup(struct temac_local *lp, struct platform_device *op,
                                struct device_node *np)
{
        unsigned int dcrs;

        /* setup the dcr address mapping if it's in the device tree */

        dcrs = dcr_resource_start(np, 0);
        if (dcrs != 0) {
                lp->sdma_dcrs = dcr_map(np, dcrs, dcr_resource_len(np, 0));
                lp->dma_in = temac_dma_dcr_in;
                lp->dma_out = temac_dma_dcr_out;
                dev_dbg(&op->dev, "DCR base: %x\n", dcrs);
                return 0;
        }
        /* no DCR in the device tree, indicate a failure */
        return -1;
}

#else

/*
 * temac_dcr_setup - This is a stub for when DCR is not supported,
 * such as with MicroBlaze and x86
 */
static int temac_dcr_setup(struct temac_local *lp, struct platform_device *op,
                                struct device_node *np)
{
        return -1;
}

#endif

/*
 * temac_dma_bd_release - Release buffer descriptor rings
 */
static void temac_dma_bd_release(struct net_device *ndev)
{
        struct temac_local *lp = netdev_priv(ndev);
        int i;

        /* Reset Local Link (DMA) */
        lp->dma_out(lp, DMA_CONTROL_REG, DMA_CONTROL_RST);

        for (i = 0; i < lp->rx_bd_num; i++) {
                if (!lp->rx_skb[i])
                        break;
                else {
                        dma_unmap_single(ndev->dev.parent, lp->rx_bd_v[i].phys,
                                        XTE_MAX_JUMBO_FRAME_SIZE, DMA_FROM_DEVICE);
                        dev_kfree_skb(lp->rx_skb[i]);
                }
        }
        if (lp->rx_bd_v)
                dma_free_coherent(ndev->dev.parent,
                                  sizeof(*lp->rx_bd_v) * lp->rx_bd_num,
                                  lp->rx_bd_v, lp->rx_bd_p);
        if (lp->tx_bd_v)
                dma_free_coherent(ndev->dev.parent,
                                  sizeof(*lp->tx_bd_v) * lp->tx_bd_num,
                                  lp->tx_bd_v, lp->tx_bd_p);
}

/*
 * 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;
        dma_addr_t skb_dma_addr;
        int i;

        lp->rx_skb = devm_kcalloc(&ndev->dev, lp->rx_bd_num,
                                  sizeof(*lp->rx_skb), GFP_KERNEL);
        if (!lp->rx_skb)
                goto out;

        /* allocate the tx and rx ring buffer descriptors. */
        /* returns a virtual address and a physical address. */
        lp->tx_bd_v = dma_alloc_coherent(ndev->dev.parent,
                                         sizeof(*lp->tx_bd_v) * lp->tx_bd_num,
                                         &lp->tx_bd_p, GFP_KERNEL);
        if (!lp->tx_bd_v)
                goto out;

        lp->rx_bd_v = dma_alloc_coherent(ndev->dev.parent,
                                         sizeof(*lp->rx_bd_v) * lp->rx_bd_num,
                                         &lp->rx_bd_p, GFP_KERNEL);
        if (!lp->rx_bd_v)
                goto out;

        for (i = 0; i < lp->tx_bd_num; i++) {
                lp->tx_bd_v[i].next = cpu_to_be32(lp->tx_bd_p
                        + sizeof(*lp->tx_bd_v) * ((i + 1) % lp->tx_bd_num));
        }

        for (i = 0; i < lp->rx_bd_num; i++) {
                lp->rx_bd_v[i].next = cpu_to_be32(lp->rx_bd_p
                        + sizeof(*lp->rx_bd_v) * ((i + 1) % lp->rx_bd_num));

                skb = netdev_alloc_skb_ip_align(ndev,
                                                XTE_MAX_JUMBO_FRAME_SIZE);
                if (!skb)
                        goto out;

                lp->rx_skb[i] = skb;
                /* returns physical address of skb->data */
                skb_dma_addr = dma_map_single(ndev->dev.parent, skb->data,
                                              XTE_MAX_JUMBO_FRAME_SIZE,
                                              DMA_FROM_DEVICE);
                if (dma_mapping_error(ndev->dev.parent, skb_dma_addr))
                        goto out;
                lp->rx_bd_v[i].phys = cpu_to_be32(skb_dma_addr);
                lp->rx_bd_v[i].len = cpu_to_be32(XTE_MAX_JUMBO_FRAME_SIZE);
                lp->rx_bd_v[i].app0 = cpu_to_be32(STS_CTRL_APP0_IRQONEND);
        }

        /* Configure DMA channel (irq setup) */
        lp->dma_out(lp, TX_CHNL_CTRL,
                    lp->coalesce_delay_tx << 24 | lp->coalesce_count_tx << 16 |
                    0x00000400 | // Use 1 Bit Wide Counters. Currently Not Used!
                    CHNL_CTRL_IRQ_EN | CHNL_CTRL_IRQ_ERR_EN |
                    CHNL_CTRL_IRQ_DLY_EN | CHNL_CTRL_IRQ_COAL_EN);
        lp->dma_out(lp, RX_CHNL_CTRL,
                    lp->coalesce_delay_rx << 24 | lp->coalesce_count_rx << 16 |
                    CHNL_CTRL_IRQ_IOE |
                    CHNL_CTRL_IRQ_EN | CHNL_CTRL_IRQ_ERR_EN |
                    CHNL_CTRL_IRQ_DLY_EN | CHNL_CTRL_IRQ_COAL_EN);

        /* Init descriptor indexes */
        lp->tx_bd_ci = 0;
        lp->tx_bd_tail = 0;
        lp->rx_bd_ci = 0;
        lp->rx_bd_tail = lp->rx_bd_num - 1;

        /* Enable RX DMA transfers */
        wmb();
        lp->dma_out(lp, RX_CURDESC_PTR,  lp->rx_bd_p);
        lp->dma_out(lp, RX_TAILDESC_PTR,
                       lp->rx_bd_p + (sizeof(*lp->rx_bd_v) * lp->rx_bd_tail));

        /* Prepare for TX DMA transfer */
        lp->dma_out(lp, TX_CURDESC_PTR, lp->tx_bd_p);

        return 0;

out:
        temac_dma_bd_release(ndev);
        return -ENOMEM;
}

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

static void temac_do_set_mac_address(struct net_device *ndev)
{
        struct temac_local *lp = netdev_priv(ndev);
        unsigned long flags;

        /* set up unicast MAC address filter set its mac address */
        spin_lock_irqsave(lp->indirect_lock, flags);
        temac_indirect_out32_locked(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_locked(lp, XTE_UAW1_OFFSET,
                                    (ndev->dev_addr[4] & 0x000000ff) |
                                    (ndev->dev_addr[5] << 8));
        spin_unlock_irqrestore(lp->indirect_lock, flags);
}

static int temac_init_mac_address(struct net_device *ndev, const void *address)
{
        memcpy(ndev->dev_addr, address, ETH_ALEN);
        if (!is_valid_ether_addr(ndev->dev_addr))
                eth_hw_addr_random(ndev);
        temac_do_set_mac_address(ndev);
        return 0;
}

static int temac_set_mac_address(struct net_device *ndev, void *p)
{
        struct sockaddr *addr = p;

        if (!is_valid_ether_addr(addr->sa_data))
                return -EADDRNOTAVAIL;
        memcpy(ndev->dev_addr, addr->sa_data, ETH_ALEN);
        temac_do_set_mac_address(ndev);
        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;
        int i = 0;
        unsigned long flags;
        bool promisc_mode_disabled = false;

        if (ndev->flags & (IFF_PROMISC | IFF_ALLMULTI) ||
            (netdev_mc_count(ndev) > MULTICAST_CAM_TABLE_NUM)) {
                temac_indirect_out32(lp, XTE_AFM_OFFSET, XTE_AFM_EPPRM_MASK);
                dev_info(&ndev->dev, "Promiscuous mode enabled.\n");
                return;
        }

        spin_lock_irqsave(lp->indirect_lock, flags);

        if (!netdev_mc_empty(ndev)) {
                struct netdev_hw_addr *ha;

                netdev_for_each_mc_addr(ha, ndev) {
                        if (WARN_ON(i >= MULTICAST_CAM_TABLE_NUM))
                                break;
                        multi_addr_msw = ((ha->addr[3] << 24) |
                                          (ha->addr[2] << 16) |
                                          (ha->addr[1] << 8) |
                                          (ha->addr[0]));
                        temac_indirect_out32_locked(lp, XTE_MAW0_OFFSET,
                                                    multi_addr_msw);
                        multi_addr_lsw = ((ha->addr[5] << 8) |
                                          (ha->addr[4]) | (i << 16));
                        temac_indirect_out32_locked(lp, XTE_MAW1_OFFSET,
                                                    multi_addr_lsw);
                        i++;
                }
        }

        /* Clear all or remaining/unused address table entries */
        while (i < MULTICAST_CAM_TABLE_NUM) {
                temac_indirect_out32_locked(lp, XTE_MAW0_OFFSET, 0);
                temac_indirect_out32_locked(lp, XTE_MAW1_OFFSET, i << 16);
                i++;
        }

        /* Enable address filter block if currently disabled */
        if (temac_indirect_in32_locked(lp, XTE_AFM_OFFSET)
            & XTE_AFM_EPPRM_MASK) {
                temac_indirect_out32_locked(lp, XTE_AFM_OFFSET, 0);
                promisc_mode_disabled = true;
        }

        spin_unlock_irqrestore(lp->indirect_lock, flags);

        if (promisc_mode_disabled)
                dev_info(&ndev->dev, "Promiscuous mode disabled.\n");
}

static 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;
        unsigned long flags;

        spin_lock_irqsave(lp->indirect_lock, flags);
        while (tp->opt) {
                reg = temac_indirect_in32_locked(lp, tp->reg) & ~tp->m_or;
                if (options & tp->opt) {
                        reg |= tp->m_or;
                        temac_indirect_out32_locked(lp, tp->reg, reg);
                }
                tp++;
        }
        spin_unlock_irqrestore(lp->indirect_lock, flags);
        lp->options |= options;

        return 0;
}

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

        /* Perform a software reset */

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

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

        /* 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 */
        spin_lock_irqsave(lp->indirect_lock, flags);
        val = temac_indirect_in32_locked(lp, XTE_RXC1_OFFSET);
        temac_indirect_out32_locked(lp, XTE_RXC1_OFFSET,
                                    val & ~XTE_RXC1_RXEN_MASK);
        spin_unlock_irqrestore(lp->indirect_lock, flags);

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

        if (temac_dma_bd_init(ndev)) {
                dev_err(&ndev->dev,
                                "temac_device_reset descriptor allocation failed\n");
        }

        spin_lock_irqsave(lp->indirect_lock, flags);
        temac_indirect_out32_locked(lp, XTE_RXC0_OFFSET, 0);
        temac_indirect_out32_locked(lp, XTE_RXC1_OFFSET, 0);
        temac_indirect_out32_locked(lp, XTE_TXC_OFFSET, 0);
        temac_indirect_out32_locked(lp, XTE_FCC_OFFSET, XTE_FCC_RXFLO_MASK);
        spin_unlock_irqrestore(lp->indirect_lock, flags);

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

        temac_do_set_mac_address(ndev);

        /* 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 */
        netif_trans_update(ndev); /* prevent tx timeout */
}

static void temac_adjust_link(struct net_device *ndev)
{
        struct temac_local *lp = netdev_priv(ndev);
        struct phy_device *phy = ndev->phydev;
        u32 mii_speed;
        int link_state;
        unsigned long flags;

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

        if (lp->last_link != link_state) {
                spin_lock_irqsave(lp->indirect_lock, flags);
                mii_speed = temac_indirect_in32_locked(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_locked(lp, XTE_EMCFG_OFFSET, mii_speed);
                spin_unlock_irqrestore(lp->indirect_lock, flags);

                lp->last_link = link_state;
                phy_print_status(phy);
        }
}

#ifdef CONFIG_64BIT

static void ptr_to_txbd(void *p, struct cdmac_bd *bd)
{
        bd->app3 = (u32)(((u64)p) >> 32);
        bd->app4 = (u32)((u64)p & 0xFFFFFFFF);
}

static void *ptr_from_txbd(struct cdmac_bd *bd)
{
        return (void *)(((u64)(bd->app3) << 32) | bd->app4);
}

#else

static void ptr_to_txbd(void *p, struct cdmac_bd *bd)
{
        bd->app4 = (u32)p;
}

static void *ptr_from_txbd(struct cdmac_bd *bd)
{
        return (void *)(bd->app4);
}

#endif

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;
        struct sk_buff *skb;

        cur_p = &lp->tx_bd_v[lp->tx_bd_ci];
        stat = be32_to_cpu(cur_p->app0);

        while (stat & STS_CTRL_APP0_CMPLT) {
                /* Make sure that the other fields are read after bd is
                 * released by dma
                 */
                rmb();
                dma_unmap_single(ndev->dev.parent, be32_to_cpu(cur_p->phys),
                                 be32_to_cpu(cur_p->len), DMA_TO_DEVICE);
                skb = (struct sk_buff *)ptr_from_txbd(cur_p);
                if (skb)
                        dev_consume_skb_irq(skb);
                cur_p->app1 = 0;
                cur_p->app2 = 0;
                cur_p->app3 = 0;
                cur_p->app4 = 0;

                ndev->stats.tx_packets++;
                ndev->stats.tx_bytes += be32_to_cpu(cur_p->len);

                /* app0 must be visible last, as it is used to flag
                 * availability of the bd
                 */
                smp_mb();
                cur_p->app0 = 0;

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

                cur_p = &lp->tx_bd_v[lp->tx_bd_ci];
                stat = be32_to_cpu(cur_p->app0);
        }

        /* Matches barrier in temac_start_xmit */
        smp_mb();

        netif_wake_queue(ndev);
}

static inline int temac_check_tx_bd_space(struct temac_local *lp, int num_frag)
{
        struct cdmac_bd *cur_p;
        int tail;

        tail = lp->tx_bd_tail;
        cur_p = &lp->tx_bd_v[tail];

        do {
                if (cur_p->app0)
                        return NETDEV_TX_BUSY;

                /* Make sure to read next bd app0 after this one */
                rmb();

                tail++;
                if (tail >= lp->tx_bd_num)
                        tail = 0;

                cur_p = &lp->tx_bd_v[tail];
                num_frag--;
        } while (num_frag >= 0);

        return 0;
}

static netdev_tx_t
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 tail_p, skb_dma_addr;
        int ii;
        unsigned long num_frag;
        skb_frag_t *frag;

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

        if (temac_check_tx_bd_space(lp, num_frag + 1)) {
                if (netif_queue_stopped(ndev))
                        return NETDEV_TX_BUSY;

                netif_stop_queue(ndev);

                /* Matches barrier in temac_start_xmit_done */
                smp_mb();

                /* Space might have just been freed - check again */
                if (temac_check_tx_bd_space(lp, num_frag + 1))
                        return NETDEV_TX_BUSY;

                netif_wake_queue(ndev);
        }

        cur_p->app0 = 0;
        if (skb->ip_summed == CHECKSUM_PARTIAL) {
                unsigned int csum_start_off = skb_checksum_start_offset(skb);
                unsigned int csum_index_off = csum_start_off + skb->csum_offset;

                cur_p->app0 |= cpu_to_be32(0x000001); /* TX Checksum Enabled */
                cur_p->app1 = cpu_to_be32((csum_start_off << 16)
                                          | csum_index_off);
                cur_p->app2 = 0;  /* initial checksum seed */
        }

        cur_p->app0 |= cpu_to_be32(STS_CTRL_APP0_SOP);
        skb_dma_addr = dma_map_single(ndev->dev.parent, skb->data,
                                      skb_headlen(skb), DMA_TO_DEVICE);
        cur_p->len = cpu_to_be32(skb_headlen(skb));
        if (WARN_ON_ONCE(dma_mapping_error(ndev->dev.parent, skb_dma_addr))) {
                dev_kfree_skb_any(skb);
                ndev->stats.tx_dropped++;
                return NETDEV_TX_OK;
        }
        cur_p->phys = cpu_to_be32(skb_dma_addr);

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

                cur_p = &lp->tx_bd_v[lp->tx_bd_tail];
                skb_dma_addr = dma_map_single(ndev->dev.parent,
                                              skb_frag_address(frag),
                                              skb_frag_size(frag),
                                              DMA_TO_DEVICE);
                if (dma_mapping_error(ndev->dev.parent, skb_dma_addr)) {
                        if (--lp->tx_bd_tail < 0)
                                lp->tx_bd_tail = lp->tx_bd_num - 1;
                        cur_p = &lp->tx_bd_v[lp->tx_bd_tail];
                        while (--ii >= 0) {
                                --frag;
                                dma_unmap_single(ndev->dev.parent,
                                                 be32_to_cpu(cur_p->phys),
                                                 skb_frag_size(frag),
                                                 DMA_TO_DEVICE);
                                if (--lp->tx_bd_tail < 0)
                                        lp->tx_bd_tail = lp->tx_bd_num - 1;
                                cur_p = &lp->tx_bd_v[lp->tx_bd_tail];
                        }
                        dma_unmap_single(ndev->dev.parent,
                                         be32_to_cpu(cur_p->phys),
                                         skb_headlen(skb), DMA_TO_DEVICE);
                        dev_kfree_skb_any(skb);
                        ndev->stats.tx_dropped++;
                        return NETDEV_TX_OK;
                }
                cur_p->phys = cpu_to_be32(skb_dma_addr);
                cur_p->len = cpu_to_be32(skb_frag_size(frag));
                cur_p->app0 = 0;
                frag++;
        }
        cur_p->app0 |= cpu_to_be32(STS_CTRL_APP0_EOP);

        /* Mark last fragment with skb address, so it can be consumed
         * in temac_start_xmit_done()
         */
        ptr_to_txbd((void *)skb, cur_p);

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

        skb_tx_timestamp(skb);

        /* Kick off the transfer */
        wmb();
        lp->dma_out(lp, TX_TAILDESC_PTR, tail_p); /* DMA start */

        if (temac_check_tx_bd_space(lp, MAX_SKB_FRAGS + 1))
                netif_stop_queue(ndev);

        return NETDEV_TX_OK;
}

static int ll_temac_recv_buffers_available(struct temac_local *lp)
{
        int available;

        if (!lp->rx_skb[lp->rx_bd_ci])
                return 0;
        available = 1 + lp->rx_bd_tail - lp->rx_bd_ci;
        if (available <= 0)
                available += lp->rx_bd_num;
        return available;
}

static void ll_temac_recv(struct net_device *ndev)
{
        struct temac_local *lp = netdev_priv(ndev);
        unsigned long flags;
        int rx_bd;
        bool update_tail = false;

        spin_lock_irqsave(&lp->rx_lock, flags);

        /* Process all received buffers, passing them on network
         * stack.  After this, the buffer descriptors will be in an
         * un-allocated stage, where no skb is allocated for it, and
         * they are therefore not available for TEMAC/DMA.
         */
        do {
                struct cdmac_bd *bd = &lp->rx_bd_v[lp->rx_bd_ci];
                struct sk_buff *skb = lp->rx_skb[lp->rx_bd_ci];
                unsigned int bdstat = be32_to_cpu(bd->app0);
                int length;

                /* While this should not normally happen, we can end
                 * here when GFP_ATOMIC allocations fail, and we
                 * therefore have un-allocated buffers.
                 */
                if (!skb)
                        break;

                /* Loop over all completed buffer descriptors */
                if (!(bdstat & STS_CTRL_APP0_CMPLT))
                        break;

                dma_unmap_single(ndev->dev.parent, be32_to_cpu(bd->phys),
                                 XTE_MAX_JUMBO_FRAME_SIZE, DMA_FROM_DEVICE);
                /* The buffer is not valid for DMA anymore */
                bd->phys = 0;
                bd->len = 0;

                length = be32_to_cpu(bd->app4) & 0x3FFF;

                skb_put(skb, length);
                skb->protocol = eth_type_trans(skb, ndev);
                skb_checksum_none_assert(skb);

                /* if we're doing rx csum offload, set it up */
                if (((lp->temac_features & TEMAC_FEATURE_RX_CSUM) != 0) &&
                    (skb->protocol == htons(ETH_P_IP)) &&
                    (skb->len > 64)) {

                        /* Convert from device endianness (be32) to cpu
                         * endiannes, and if necessary swap the bytes
                         * (back) for proper IP checksum byte order
                         * (be16).
                         */
                        skb->csum = htons(be32_to_cpu(bd->app3) & 0xFFFF);
                        skb->ip_summed = CHECKSUM_COMPLETE;
                }

                if (!skb_defer_rx_timestamp(skb))
                        netif_rx(skb);
                /* The skb buffer is now owned by network stack above */
                lp->rx_skb[lp->rx_bd_ci] = NULL;

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

                rx_bd = lp->rx_bd_ci;
                if (++lp->rx_bd_ci >= lp->rx_bd_num)
                        lp->rx_bd_ci = 0;
        } while (rx_bd != lp->rx_bd_tail);

        /* DMA operations will halt when the last buffer descriptor is
         * processed (ie. the one pointed to by RX_TAILDESC_PTR).
         * When that happens, no more interrupt events will be
         * generated.  No IRQ_COAL or IRQ_DLY, and not even an
         * IRQ_ERR.  To avoid stalling, we schedule a delayed work
         * when there is a potential risk of that happening.  The work
         * will call this function, and thus re-schedule itself until
         * enough buffers are available again.
         */
        if (ll_temac_recv_buffers_available(lp) < lp->coalesce_count_rx)
                schedule_delayed_work(&lp->restart_work, HZ / 1000);

        /* Allocate new buffers for those buffer descriptors that were
         * passed to network stack.  Note that GFP_ATOMIC allocations
         * can fail (e.g. when a larger burst of GFP_ATOMIC
         * allocations occurs), so while we try to allocate all
         * buffers in the same interrupt where they were processed, we
         * continue with what we could get in case of allocation
         * failure.  Allocation of remaining buffers will be retried
         * in following calls.
         */
        while (1) {
                struct sk_buff *skb;
                struct cdmac_bd *bd;
                dma_addr_t skb_dma_addr;

                rx_bd = lp->rx_bd_tail + 1;
                if (rx_bd >= lp->rx_bd_num)
                        rx_bd = 0;
                bd = &lp->rx_bd_v[rx_bd];

                if (bd->phys)
                        break;  /* All skb's allocated */

                skb = netdev_alloc_skb_ip_align(ndev, XTE_MAX_JUMBO_FRAME_SIZE);
                if (!skb) {
                        dev_warn(&ndev->dev, "skb alloc failed\n");
                        break;
                }

                skb_dma_addr = dma_map_single(ndev->dev.parent, skb->data,
                                              XTE_MAX_JUMBO_FRAME_SIZE,
                                              DMA_FROM_DEVICE);
                if (WARN_ON_ONCE(dma_mapping_error(ndev->dev.parent,
                                                   skb_dma_addr))) {
                        dev_kfree_skb_any(skb);
                        break;
                }

                bd->phys = cpu_to_be32(skb_dma_addr);
                bd->len = cpu_to_be32(XTE_MAX_JUMBO_FRAME_SIZE);
                bd->app0 = cpu_to_be32(STS_CTRL_APP0_IRQONEND);
                lp->rx_skb[rx_bd] = skb;

                lp->rx_bd_tail = rx_bd;
                update_tail = true;
        }

        /* Move tail pointer when buffers have been allocated */
        if (update_tail) {
                lp->dma_out(lp, RX_TAILDESC_PTR,
                        lp->rx_bd_p + sizeof(*lp->rx_bd_v) * lp->rx_bd_tail);
        }

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

/* Function scheduled to ensure a restart in case of DMA halt
 * condition caused by running out of buffer descriptors.
 */
static void ll_temac_restart_work_func(struct work_struct *work)
{
        struct temac_local *lp = container_of(work, struct temac_local,
                                              restart_work.work);
        struct net_device *ndev = lp->ndev;

        ll_temac_recv(ndev);
}

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 = lp->dma_in(lp, TX_IRQ_REG);
        lp->dma_out(lp, TX_IRQ_REG, status);

        if (status & (IRQ_COAL | IRQ_DLY))
                temac_start_xmit_done(lp->ndev);
        if (status & (IRQ_ERR | IRQ_DMAERR))
                dev_err_ratelimited(&ndev->dev,
                                    "TX error 0x%x TX_CHNL_STS=0x%08x\n",
                                    status, lp->dma_in(lp, TX_CHNL_STS));

        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 = lp->dma_in(lp, RX_IRQ_REG);
        lp->dma_out(lp, RX_IRQ_REG, status);

        if (status & (IRQ_COAL | IRQ_DLY))
                ll_temac_recv(lp->ndev);
        if (status & (IRQ_ERR | IRQ_DMAERR))
                dev_err_ratelimited(&ndev->dev,
                                    "RX error 0x%x RX_CHNL_STS=0x%08x\n",
                                    status, lp->dma_in(lp, RX_CHNL_STS));

        return IRQ_HANDLED;
}

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

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

        if (lp->phy_node) {
                phydev = of_phy_connect(lp->ndev, lp->phy_node,
                                        temac_adjust_link, 0, 0);
                if (!phydev) {
                        dev_err(lp->dev, "of_phy_connect() failed\n");
                        return -ENODEV;
                }
                phy_start(phydev);
        } else if (strlen(lp->phy_name) > 0) {
                phydev = phy_connect(lp->ndev, lp->phy_name, temac_adjust_link,
                                     lp->phy_interface);
                if (IS_ERR(phydev)) {
                        dev_err(lp->dev, "phy_connect() failed\n");
                        return PTR_ERR(phydev);
                }
                phy_start(phydev);
        }

        temac_device_reset(ndev);

        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;

        return 0;

 err_rx_irq:
        free_irq(lp->tx_irq, ndev);
 err_tx_irq:
        if (phydev)
                phy_disconnect(phydev);
        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);
        struct phy_device *phydev = ndev->phydev;

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

        cancel_delayed_work_sync(&lp->restart_work);

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

        if (phydev)
                phy_disconnect(phydev);

        temac_dma_bd_release(ndev);

        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, ndev);
        ll_temac_tx_irq(lp->rx_irq, ndev);

        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_rx_mode = temac_set_multicast_list,
        .ndo_set_mac_address = temac_set_mac_address,
        .ndo_validate_addr = eth_validate_addr,
        .ndo_eth_ioctl = phy_do_ioctl_running,
#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", lp->dma_in(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,
};

/* ---------------------------------------------------------------------
 * ethtool support
 */

static void ll_temac_ethtools_get_ringparam(struct net_device *ndev,
                                            struct ethtool_ringparam *ering)
{
        struct temac_local *lp = netdev_priv(ndev);

        ering->rx_max_pending = RX_BD_NUM_MAX;
        ering->rx_mini_max_pending = 0;
        ering->rx_jumbo_max_pending = 0;
        ering->tx_max_pending = TX_BD_NUM_MAX;
        ering->rx_pending = lp->rx_bd_num;
        ering->rx_mini_pending = 0;
        ering->rx_jumbo_pending = 0;
        ering->tx_pending = lp->tx_bd_num;
}

static int ll_temac_ethtools_set_ringparam(struct net_device *ndev,
                                           struct ethtool_ringparam *ering)
{
        struct temac_local *lp = netdev_priv(ndev);

        if (ering->rx_pending > RX_BD_NUM_MAX ||
            ering->rx_mini_pending ||
            ering->rx_jumbo_pending ||
            ering->rx_pending > TX_BD_NUM_MAX)
                return -EINVAL;

        if (netif_running(ndev))
                return -EBUSY;

        lp->rx_bd_num = ering->rx_pending;
        lp->tx_bd_num = ering->tx_pending;
        return 0;
}

static int
ll_temac_ethtools_get_coalesce(struct net_device *ndev,
                               struct ethtool_coalesce *ec,
                               struct kernel_ethtool_coalesce *kernel_coal,
                               struct netlink_ext_ack *extack)
{
        struct temac_local *lp = netdev_priv(ndev);

        ec->rx_max_coalesced_frames = lp->coalesce_count_rx;
        ec->tx_max_coalesced_frames = lp->coalesce_count_tx;
        ec->rx_coalesce_usecs = (lp->coalesce_delay_rx * 512) / 100;
        ec->tx_coalesce_usecs = (lp->coalesce_delay_tx * 512) / 100;
        return 0;
}

static int
ll_temac_ethtools_set_coalesce(struct net_device *ndev,
                               struct ethtool_coalesce *ec,
                               struct kernel_ethtool_coalesce *kernel_coal,
                               struct netlink_ext_ack *extack)
{
        struct temac_local *lp = netdev_priv(ndev);

        if (netif_running(ndev)) {
                netdev_err(ndev,
                           "Please stop netif before applying configuration\n");
                return -EFAULT;
        }

        if (ec->rx_max_coalesced_frames)
                lp->coalesce_count_rx = ec->rx_max_coalesced_frames;
        if (ec->tx_max_coalesced_frames)
                lp->coalesce_count_tx = ec->tx_max_coalesced_frames;
        /* With typical LocalLink clock speed of 200 MHz and
         * C_PRESCALAR=1023, each delay count corresponds to 5.12 us.
         */
        if (ec->rx_coalesce_usecs)
                lp->coalesce_delay_rx =
                        min(255U, (ec->rx_coalesce_usecs * 100) / 512);
        if (ec->tx_coalesce_usecs)
                lp->coalesce_delay_tx =
                        min(255U, (ec->tx_coalesce_usecs * 100) / 512);

        return 0;
}

static const struct ethtool_ops temac_ethtool_ops = {
        .supported_coalesce_params = ETHTOOL_COALESCE_USECS |
                                     ETHTOOL_COALESCE_MAX_FRAMES,
        .nway_reset = phy_ethtool_nway_reset,
        .get_link = ethtool_op_get_link,
        .get_ts_info = ethtool_op_get_ts_info,
        .get_link_ksettings = phy_ethtool_get_link_ksettings,
        .set_link_ksettings = phy_ethtool_set_link_ksettings,
        .get_ringparam  = ll_temac_ethtools_get_ringparam,
        .set_ringparam  = ll_temac_ethtools_set_ringparam,
        .get_coalesce   = ll_temac_ethtools_get_coalesce,
        .set_coalesce   = ll_temac_ethtools_set_coalesce,
};

static int temac_probe(struct platform_device *pdev)
{
        struct ll_temac_platform_data *pdata = dev_get_platdata(&pdev->dev);
        struct device_node *temac_np = dev_of_node(&pdev->dev), *dma_np;
        struct temac_local *lp;
        struct net_device *ndev;
        u8 addr[ETH_ALEN];
        __be32 *p;
        bool little_endian;
        int rc = 0;

        /* Init network device structure */
        ndev = devm_alloc_etherdev(&pdev->dev, sizeof(*lp));
        if (!ndev)
                return -ENOMEM;

        platform_set_drvdata(pdev, ndev);
        SET_NETDEV_DEV(ndev, &pdev->dev);
        ndev->features = NETIF_F_SG;
        ndev->netdev_ops = &temac_netdev_ops;
        ndev->ethtool_ops = &temac_ethtool_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_CTAG_TX; /* Transmit VLAN hw accel */
        ndev->features |= NETIF_F_HW_VLAN_CTAG_RX; /* Receive VLAN hw acceleration */
        ndev->features |= NETIF_F_HW_VLAN_CTAG_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 = &pdev->dev;
        lp->options = XTE_OPTION_DEFAULTS;
        lp->rx_bd_num = RX_BD_NUM_DEFAULT;
        lp->tx_bd_num = TX_BD_NUM_DEFAULT;
        spin_lock_init(&lp->rx_lock);
        INIT_DELAYED_WORK(&lp->restart_work, ll_temac_restart_work_func);

        /* Setup mutex for synchronization of indirect register access */
        if (pdata) {
                if (!pdata->indirect_lock) {
                        dev_err(&pdev->dev,
                                "indirect_lock missing in platform_data\n");
                        return -EINVAL;
                }
                lp->indirect_lock = pdata->indirect_lock;
        } else {
                lp->indirect_lock = devm_kmalloc(&pdev->dev,
                                                 sizeof(*lp->indirect_lock),
                                                 GFP_KERNEL);
                spin_lock_init(lp->indirect_lock);
        }

        /* map device registers */
        lp->regs = devm_platform_ioremap_resource_byname(pdev, 0);
        if (IS_ERR(lp->regs)) {
                dev_err(&pdev->dev, "could not map TEMAC registers\n");
                return -ENOMEM;
        }

        /* Select register access functions with the specified
         * endianness mode.  Default for OF devices is big-endian.
         */
        little_endian = false;
        if (temac_np) {
                if (of_get_property(temac_np, "little-endian", NULL))
                        little_endian = true;
        } else if (pdata) {
                little_endian = pdata->reg_little_endian;
        }
        if (little_endian) {
                lp->temac_ior = _temac_ior_le;
                lp->temac_iow = _temac_iow_le;
        } else {
                lp->temac_ior = _temac_ior_be;
                lp->temac_iow = _temac_iow_be;
        }

        /* Setup checksum offload, but default to off if not specified */
        lp->temac_features = 0;
        if (temac_np) {
                p = (__be32 *)of_get_property(temac_np, "xlnx,txcsum", NULL);
                if (p && be32_to_cpu(*p))
                        lp->temac_features |= TEMAC_FEATURE_TX_CSUM;
                p = (__be32 *)of_get_property(temac_np, "xlnx,rxcsum", NULL);
                if (p && be32_to_cpu(*p))
                        lp->temac_features |= TEMAC_FEATURE_RX_CSUM;
        } else if (pdata) {
                if (pdata->txcsum)
                        lp->temac_features |= TEMAC_FEATURE_TX_CSUM;
                if (pdata->rxcsum)
                        lp->temac_features |= TEMAC_FEATURE_RX_CSUM;
        }
        if (lp->temac_features & TEMAC_FEATURE_TX_CSUM)
                /* Can checksum TCP/UDP over IPv4. */
                ndev->features |= NETIF_F_IP_CSUM;

        /* Defaults for IRQ delay/coalescing setup.  These are
         * configuration values, so does not belong in device-tree.
         */
        lp->coalesce_delay_tx = 0x10;
        lp->coalesce_count_tx = 0x22;
        lp->coalesce_delay_rx = 0xff;
        lp->coalesce_count_rx = 0x07;

        /* Setup LocalLink DMA */
        if (temac_np) {
                /* Find the DMA node, map the DMA registers, and
                 * decode the DMA IRQs.
                 */
                dma_np = of_parse_phandle(temac_np, "llink-connected", 0);
                if (!dma_np) {
                        dev_err(&pdev->dev, "could not find DMA node\n");
                        return -ENODEV;
                }

                /* Setup the DMA register accesses, could be DCR or
                 * memory mapped.
                 */
                if (temac_dcr_setup(lp, pdev, dma_np)) {
                        /* no DCR in the device tree, try non-DCR */
                        lp->sdma_regs = devm_of_iomap(&pdev->dev, dma_np, 0,
                                                      NULL);
                        if (IS_ERR(lp->sdma_regs)) {
                                dev_err(&pdev->dev,
                                        "unable to map DMA registers\n");
                                of_node_put(dma_np);
                                return PTR_ERR(lp->sdma_regs);
                        }
                        if (of_get_property(dma_np, "little-endian", NULL)) {
                                lp->dma_in = temac_dma_in32_le;
                                lp->dma_out = temac_dma_out32_le;
                        } else {
                                lp->dma_in = temac_dma_in32_be;
                                lp->dma_out = temac_dma_out32_be;
                        }
                        dev_dbg(&pdev->dev, "MEM base: %p\n", lp->sdma_regs);
                }

                /* Get DMA RX and TX interrupts */
                lp->rx_irq = irq_of_parse_and_map(dma_np, 0);
                lp->tx_irq = irq_of_parse_and_map(dma_np, 1);

                /* Finished with the DMA node; drop the reference */
                of_node_put(dma_np);
        } else if (pdata) {
                /* 2nd memory resource specifies DMA registers */
                lp->sdma_regs = devm_platform_ioremap_resource(pdev, 1);
                if (IS_ERR(lp->sdma_regs)) {
                        dev_err(&pdev->dev,
                                "could not map DMA registers\n");
                        return PTR_ERR(lp->sdma_regs);
                }
                if (pdata->dma_little_endian) {
                        lp->dma_in = temac_dma_in32_le;
                        lp->dma_out = temac_dma_out32_le;
                } else {
                        lp->dma_in = temac_dma_in32_be;
                        lp->dma_out = temac_dma_out32_be;
                }

                /* Get DMA RX and TX interrupts */
                lp->rx_irq = platform_get_irq(pdev, 0);
                lp->tx_irq = platform_get_irq(pdev, 1);

                /* IRQ delay/coalescing setup */
                if (pdata->tx_irq_timeout || pdata->tx_irq_count) {
                        lp->coalesce_delay_tx = pdata->tx_irq_timeout;
                        lp->coalesce_count_tx = pdata->tx_irq_count;
                }
                if (pdata->rx_irq_timeout || pdata->rx_irq_count) {
                        lp->coalesce_delay_rx = pdata->rx_irq_timeout;
                        lp->coalesce_count_rx = pdata->rx_irq_count;
                }
        }

        /* Error handle returned DMA RX and TX interrupts */
        if (lp->rx_irq < 0) {
                if (lp->rx_irq != -EPROBE_DEFER)
                        dev_err(&pdev->dev, "could not get DMA RX irq\n");
                return lp->rx_irq;
        }
        if (lp->tx_irq < 0) {
                if (lp->tx_irq != -EPROBE_DEFER)
                        dev_err(&pdev->dev, "could not get DMA TX irq\n");
                return lp->tx_irq;
        }

        if (temac_np) {
                /* Retrieve the MAC address */
                rc = of_get_mac_address(temac_np, addr);
                if (rc) {
                        dev_err(&pdev->dev, "could not find MAC address\n");
                        return -ENODEV;
                }
                temac_init_mac_address(ndev, addr);
        } else if (pdata) {
                temac_init_mac_address(ndev, pdata->mac_addr);
        }

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

        if (temac_np) {
                lp->phy_node = of_parse_phandle(temac_np, "phy-handle", 0);
                if (lp->phy_node)
                        dev_dbg(lp->dev, "using PHY node %pOF\n", temac_np);
        } else if (pdata) {
                snprintf(lp->phy_name, sizeof(lp->phy_name),
                         PHY_ID_FMT, lp->mii_bus->id, pdata->phy_addr);
                lp->phy_interface = pdata->phy_interface;
        }

        /* 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 err_sysfs_create;
        }

        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);
err_sysfs_create:
        if (lp->phy_node)
                of_node_put(lp->phy_node);
        temac_mdio_teardown(lp);
        return rc;
}

static int temac_remove(struct platform_device *pdev)
{
        struct net_device *ndev = platform_get_drvdata(pdev);
        struct temac_local *lp = netdev_priv(ndev);

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

static const struct of_device_id temac_of_match[] = {
        { .compatible = "xlnx,xps-ll-temac-1.01.b", },
        { .compatible = "xlnx,xps-ll-temac-2.00.a", },
        { .compatible = "xlnx,xps-ll-temac-2.02.a", },
        { .compatible = "xlnx,xps-ll-temac-2.03.a", },
        {},
};
MODULE_DEVICE_TABLE(of, temac_of_match);

static struct platform_driver temac_driver = {
        .probe = temac_probe,
        .remove = temac_remove,
        .driver = {
                .name = "xilinx_temac",
                .of_match_table = temac_of_match,
        },
};

module_platform_driver(temac_driver);

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