// SPDX-License-Identifier: GPL-2.0-only
/* Altera Triple-Speed Ethernet MAC driver
 * Copyright (C) 2008-2014 Altera Corporation. All rights reserved
 *
 * Contributors:
 *   Dalon Westergreen
 *   Thomas Chou
 *   Ian Abbott
 *   Yuriy Kozlov
 *   Tobias Klauser
 *   Andriy Smolskyy
 *   Roman Bulgakov
 *   Dmytro Mytarchuk
 *   Matthew Gerlach
 *
 * Original driver contributed by SLS.
 * Major updates contributed by GlobalLogic
 */

#include <linux/atomic.h>
#include <linux/delay.h>
#include <linux/etherdevice.h>
#include <linux/if_vlan.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mii.h>
#include <linux/netdevice.h>
#include <linux/of_device.h>
#include <linux/of_mdio.h>
#include <linux/of_net.h>
#include <linux/of_platform.h>
#include <linux/phy.h>
#include <linux/platform_device.h>
#include <linux/skbuff.h>
#include <asm/cacheflush.h>

#include "altera_utils.h"
#include "altera_tse.h"
#include "altera_sgdma.h"
#include "altera_msgdma.h"

static atomic_t instance_count = ATOMIC_INIT(~0);
/* Module parameters */
static int debug = -1;
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "Message Level (-1: default, 0: no output, 16: all)");

static const u32 default_msg_level = (NETIF_MSG_DRV | NETIF_MSG_PROBE |
                                        NETIF_MSG_LINK | NETIF_MSG_IFUP |
                                        NETIF_MSG_IFDOWN);

#define RX_DESCRIPTORS 64
static int dma_rx_num = RX_DESCRIPTORS;
module_param(dma_rx_num, int, 0644);
MODULE_PARM_DESC(dma_rx_num, "Number of descriptors in the RX list");

#define TX_DESCRIPTORS 64
static int dma_tx_num = TX_DESCRIPTORS;
module_param(dma_tx_num, int, 0644);
MODULE_PARM_DESC(dma_tx_num, "Number of descriptors in the TX list");


#define POLL_PHY (-1)

/* Make sure DMA buffer size is larger than the max frame size
 * plus some alignment offset and a VLAN header. If the max frame size is
 * 1518, a VLAN header would be additional 4 bytes and additional
 * headroom for alignment is 2 bytes, 2048 is just fine.
 */
#define ALTERA_RXDMABUFFER_SIZE 2048

/* Allow network stack to resume queuing packets after we've
 * finished transmitting at least 1/4 of the packets in the queue.
 */
#define TSE_TX_THRESH(x)        (x->tx_ring_size / 4)

#define TXQUEUESTOP_THRESHHOLD  2

static const struct of_device_id altera_tse_ids[];

static inline u32 tse_tx_avail(struct altera_tse_private *priv)
{
        return priv->tx_cons + priv->tx_ring_size - priv->tx_prod - 1;
}

/* PCS Register read/write functions
 */
static u16 sgmii_pcs_read(struct altera_tse_private *priv, int regnum)
{
        return csrrd32(priv->mac_dev,
                       tse_csroffs(mdio_phy0) + regnum * 4) & 0xffff;
}

static void sgmii_pcs_write(struct altera_tse_private *priv, int regnum,
                                u16 value)
{
        csrwr32(value, priv->mac_dev, tse_csroffs(mdio_phy0) + regnum * 4);
}

/* Check PCS scratch memory */
static int sgmii_pcs_scratch_test(struct altera_tse_private *priv, u16 value)
{
        sgmii_pcs_write(priv, SGMII_PCS_SCRATCH, value);
        return (sgmii_pcs_read(priv, SGMII_PCS_SCRATCH) == value);
}

/* MDIO specific functions
 */
static int altera_tse_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
{
        struct net_device *ndev = bus->priv;
        struct altera_tse_private *priv = netdev_priv(ndev);

        /* set MDIO address */
        csrwr32((mii_id & 0x1f), priv->mac_dev,
                tse_csroffs(mdio_phy1_addr));

        /* get the data */
        return csrrd32(priv->mac_dev,
                       tse_csroffs(mdio_phy1) + regnum * 4) & 0xffff;
}

static int altera_tse_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
                                 u16 value)
{
        struct net_device *ndev = bus->priv;
        struct altera_tse_private *priv = netdev_priv(ndev);

        /* set MDIO address */
        csrwr32((mii_id & 0x1f), priv->mac_dev,
                tse_csroffs(mdio_phy1_addr));

        /* write the data */
        csrwr32(value, priv->mac_dev, tse_csroffs(mdio_phy1) + regnum * 4);
        return 0;
}

static int altera_tse_mdio_create(struct net_device *dev, unsigned int id)
{
        struct altera_tse_private *priv = netdev_priv(dev);
        int ret;
        struct device_node *mdio_node = NULL;
        struct mii_bus *mdio = NULL;
        struct device_node *child_node = NULL;

        for_each_child_of_node(priv->device->of_node, child_node) {
                if (of_device_is_compatible(child_node, "altr,tse-mdio")) {
                        mdio_node = child_node;
                        break;
                }
        }

        if (mdio_node) {
                netdev_dbg(dev, "FOUND MDIO subnode\n");
        } else {
                netdev_dbg(dev, "NO MDIO subnode\n");
                return 0;
        }

        mdio = mdiobus_alloc();
        if (mdio == NULL) {
                netdev_err(dev, "Error allocating MDIO bus\n");
                ret = -ENOMEM;
                goto put_node;
        }

        mdio->name = ALTERA_TSE_RESOURCE_NAME;
        mdio->read = &altera_tse_mdio_read;
        mdio->write = &altera_tse_mdio_write;
        snprintf(mdio->id, MII_BUS_ID_SIZE, "%s-%u", mdio->name, id);

        mdio->priv = dev;
        mdio->parent = priv->device;

        ret = of_mdiobus_register(mdio, mdio_node);
        if (ret != 0) {
                netdev_err(dev, "Cannot register MDIO bus %s\n",
                           mdio->id);
                goto out_free_mdio;
        }
        of_node_put(mdio_node);

        if (netif_msg_drv(priv))
                netdev_info(dev, "MDIO bus %s: created\n", mdio->id);

        priv->mdio = mdio;
        return 0;
out_free_mdio:
        mdiobus_free(mdio);
        mdio = NULL;
put_node:
        of_node_put(mdio_node);
        return ret;
}

static void altera_tse_mdio_destroy(struct net_device *dev)
{
        struct altera_tse_private *priv = netdev_priv(dev);

        if (priv->mdio == NULL)
                return;

        if (netif_msg_drv(priv))
                netdev_info(dev, "MDIO bus %s: removed\n",
                            priv->mdio->id);

        mdiobus_unregister(priv->mdio);
        mdiobus_free(priv->mdio);
        priv->mdio = NULL;
}

static int tse_init_rx_buffer(struct altera_tse_private *priv,
                              struct tse_buffer *rxbuffer, int len)
{
        rxbuffer->skb = netdev_alloc_skb_ip_align(priv->dev, len);
        if (!rxbuffer->skb)
                return -ENOMEM;

        rxbuffer->dma_addr = dma_map_single(priv->device, rxbuffer->skb->data,
                                                len,
                                                DMA_FROM_DEVICE);

        if (dma_mapping_error(priv->device, rxbuffer->dma_addr)) {
                netdev_err(priv->dev, "%s: DMA mapping error\n", __func__);
                dev_kfree_skb_any(rxbuffer->skb);
                return -EINVAL;
        }
        rxbuffer->dma_addr &= (dma_addr_t)~3;
        rxbuffer->len = len;
        return 0;
}

static void tse_free_rx_buffer(struct altera_tse_private *priv,
                               struct tse_buffer *rxbuffer)
{
        struct sk_buff *skb = rxbuffer->skb;
        dma_addr_t dma_addr = rxbuffer->dma_addr;

        if (skb != NULL) {
                if (dma_addr)
                        dma_unmap_single(priv->device, dma_addr,
                                         rxbuffer->len,
                                         DMA_FROM_DEVICE);
                dev_kfree_skb_any(skb);
                rxbuffer->skb = NULL;
                rxbuffer->dma_addr = 0;
        }
}

/* Unmap and free Tx buffer resources
 */
static void tse_free_tx_buffer(struct altera_tse_private *priv,
                               struct tse_buffer *buffer)
{
        if (buffer->dma_addr) {
                if (buffer->mapped_as_page)
                        dma_unmap_page(priv->device, buffer->dma_addr,
                                       buffer->len, DMA_TO_DEVICE);
                else
                        dma_unmap_single(priv->device, buffer->dma_addr,
                                         buffer->len, DMA_TO_DEVICE);
                buffer->dma_addr = 0;
        }
        if (buffer->skb) {
                dev_kfree_skb_any(buffer->skb);
                buffer->skb = NULL;
        }
}

static int alloc_init_skbufs(struct altera_tse_private *priv)
{
        unsigned int rx_descs = priv->rx_ring_size;
        unsigned int tx_descs = priv->tx_ring_size;
        int ret = -ENOMEM;
        int i;

        /* Create Rx ring buffer */
        priv->rx_ring = kcalloc(rx_descs, sizeof(struct tse_buffer),
                                GFP_KERNEL);
        if (!priv->rx_ring)
                goto err_rx_ring;

        /* Create Tx ring buffer */
        priv->tx_ring = kcalloc(tx_descs, sizeof(struct tse_buffer),
                                GFP_KERNEL);
        if (!priv->tx_ring)
                goto err_tx_ring;

        priv->tx_cons = 0;
        priv->tx_prod = 0;

        /* Init Rx ring */
        for (i = 0; i < rx_descs; i++) {
                ret = tse_init_rx_buffer(priv, &priv->rx_ring[i],
                                         priv->rx_dma_buf_sz);
                if (ret)
                        goto err_init_rx_buffers;
        }

        priv->rx_cons = 0;
        priv->rx_prod = 0;

        return 0;
err_init_rx_buffers:
        while (--i >= 0)
                tse_free_rx_buffer(priv, &priv->rx_ring[i]);
        kfree(priv->tx_ring);
err_tx_ring:
        kfree(priv->rx_ring);
err_rx_ring:
        return ret;
}

static void free_skbufs(struct net_device *dev)
{
        struct altera_tse_private *priv = netdev_priv(dev);
        unsigned int rx_descs = priv->rx_ring_size;
        unsigned int tx_descs = priv->tx_ring_size;
        int i;

        /* Release the DMA TX/RX socket buffers */
        for (i = 0; i < rx_descs; i++)
                tse_free_rx_buffer(priv, &priv->rx_ring[i]);
        for (i = 0; i < tx_descs; i++)
                tse_free_tx_buffer(priv, &priv->tx_ring[i]);


        kfree(priv->tx_ring);
}

/* Reallocate the skb for the reception process
 */
static inline void tse_rx_refill(struct altera_tse_private *priv)
{
        unsigned int rxsize = priv->rx_ring_size;
        unsigned int entry;
        int ret;

        for (; priv->rx_cons - priv->rx_prod > 0;
                        priv->rx_prod++) {
                entry = priv->rx_prod % rxsize;
                if (likely(priv->rx_ring[entry].skb == NULL)) {
                        ret = tse_init_rx_buffer(priv, &priv->rx_ring[entry],
                                priv->rx_dma_buf_sz);
                        if (unlikely(ret != 0))
                                break;
                        priv->dmaops->add_rx_desc(priv, &priv->rx_ring[entry]);
                }
        }
}

/* Pull out the VLAN tag and fix up the packet
 */
static inline void tse_rx_vlan(struct net_device *dev, struct sk_buff *skb)
{
        struct ethhdr *eth_hdr;
        u16 vid;
        if ((dev->features & NETIF_F_HW_VLAN_CTAG_RX) &&
            !__vlan_get_tag(skb, &vid)) {
                eth_hdr = (struct ethhdr *)skb->data;
                memmove(skb->data + VLAN_HLEN, eth_hdr, ETH_ALEN * 2);
                skb_pull(skb, VLAN_HLEN);
                __vlan_hwaccel_put_tag(skb, htons(ETH_P_8021Q), vid);
        }
}

/* Receive a packet: retrieve and pass over to upper levels
 */
static int tse_rx(struct altera_tse_private *priv, int limit)
{
        unsigned int count = 0;
        unsigned int next_entry;
        struct sk_buff *skb;
        unsigned int entry = priv->rx_cons % priv->rx_ring_size;
        u32 rxstatus;
        u16 pktlength;
        u16 pktstatus;

        /* Check for count < limit first as get_rx_status is changing
        * the response-fifo so we must process the next packet
        * after calling get_rx_status if a response is pending.
        * (reading the last byte of the response pops the value from the fifo.)
        */
        while ((count < limit) &&
               ((rxstatus = priv->dmaops->get_rx_status(priv)) != 0)) {
                pktstatus = rxstatus >> 16;
                pktlength = rxstatus & 0xffff;

                if ((pktstatus & 0xFF) || (pktlength == 0))
                        netdev_err(priv->dev,
                                   "RCV pktstatus %08X pktlength %08X\n",
                                   pktstatus, pktlength);

                /* DMA transfer from TSE starts with 2 additional bytes for
                 * IP payload alignment. Status returned by get_rx_status()
                 * contains DMA transfer length. Packet is 2 bytes shorter.
                 */
                pktlength -= 2;

                count++;
                next_entry = (++priv->rx_cons) % priv->rx_ring_size;

                skb = priv->rx_ring[entry].skb;
                if (unlikely(!skb)) {
                        netdev_err(priv->dev,
                                   "%s: Inconsistent Rx descriptor chain\n",
                                   __func__);
                        priv->dev->stats.rx_dropped++;
                        break;
                }
                priv->rx_ring[entry].skb = NULL;

                skb_put(skb, pktlength);

                dma_unmap_single(priv->device, priv->rx_ring[entry].dma_addr,
                                 priv->rx_ring[entry].len, DMA_FROM_DEVICE);

                if (netif_msg_pktdata(priv)) {
                        netdev_info(priv->dev, "frame received %d bytes\n",
                                    pktlength);
                        print_hex_dump(KERN_ERR, "data: ", DUMP_PREFIX_OFFSET,
                                       16, 1, skb->data, pktlength, true);
                }

                tse_rx_vlan(priv->dev, skb);

                skb->protocol = eth_type_trans(skb, priv->dev);
                skb_checksum_none_assert(skb);

                napi_gro_receive(&priv->napi, skb);

                priv->dev->stats.rx_packets++;
                priv->dev->stats.rx_bytes += pktlength;

                entry = next_entry;

                tse_rx_refill(priv);
        }

        return count;
}

/* Reclaim resources after transmission completes
 */
static int tse_tx_complete(struct altera_tse_private *priv)
{
        unsigned int txsize = priv->tx_ring_size;
        u32 ready;
        unsigned int entry;
        struct tse_buffer *tx_buff;
        int txcomplete = 0;

        spin_lock(&priv->tx_lock);

        ready = priv->dmaops->tx_completions(priv);

        /* Free sent buffers */
        while (ready && (priv->tx_cons != priv->tx_prod)) {
                entry = priv->tx_cons % txsize;
                tx_buff = &priv->tx_ring[entry];

                if (netif_msg_tx_done(priv))
                        netdev_dbg(priv->dev, "%s: curr %d, dirty %d\n",
                                   __func__, priv->tx_prod, priv->tx_cons);

                if (likely(tx_buff->skb))
                        priv->dev->stats.tx_packets++;

                tse_free_tx_buffer(priv, tx_buff);
                priv->tx_cons++;

                txcomplete++;
                ready--;
        }

        if (unlikely(netif_queue_stopped(priv->dev) &&
                     tse_tx_avail(priv) > TSE_TX_THRESH(priv))) {
                if (netif_queue_stopped(priv->dev) &&
                    tse_tx_avail(priv) > TSE_TX_THRESH(priv)) {
                        if (netif_msg_tx_done(priv))
                                netdev_dbg(priv->dev, "%s: restart transmit\n",
                                           __func__);
                        netif_wake_queue(priv->dev);
                }
        }

        spin_unlock(&priv->tx_lock);
        return txcomplete;
}

/* NAPI polling function
 */
static int tse_poll(struct napi_struct *napi, int budget)
{
        struct altera_tse_private *priv =
                        container_of(napi, struct altera_tse_private, napi);
        int rxcomplete = 0;
        unsigned long int flags;

        tse_tx_complete(priv);

        rxcomplete = tse_rx(priv, budget);

        if (rxcomplete < budget) {

                napi_complete_done(napi, rxcomplete);

                netdev_dbg(priv->dev,
                           "NAPI Complete, did %d packets with budget %d\n",
                           rxcomplete, budget);

                spin_lock_irqsave(&priv->rxdma_irq_lock, flags);
                priv->dmaops->enable_rxirq(priv);
                priv->dmaops->enable_txirq(priv);
                spin_unlock_irqrestore(&priv->rxdma_irq_lock, flags);
        }
        return rxcomplete;
}

/* DMA TX & RX FIFO interrupt routing
 */
static irqreturn_t altera_isr(int irq, void *dev_id)
{
        struct net_device *dev = dev_id;
        struct altera_tse_private *priv;

        if (unlikely(!dev)) {
                pr_err("%s: invalid dev pointer\n", __func__);
                return IRQ_NONE;
        }
        priv = netdev_priv(dev);

        spin_lock(&priv->rxdma_irq_lock);
        /* reset IRQs */
        priv->dmaops->clear_rxirq(priv);
        priv->dmaops->clear_txirq(priv);
        spin_unlock(&priv->rxdma_irq_lock);

        if (likely(napi_schedule_prep(&priv->napi))) {
                spin_lock(&priv->rxdma_irq_lock);
                priv->dmaops->disable_rxirq(priv);
                priv->dmaops->disable_txirq(priv);
                spin_unlock(&priv->rxdma_irq_lock);
                __napi_schedule(&priv->napi);
        }


        return IRQ_HANDLED;
}

/* Transmit a packet (called by the kernel). Dispatches
 * either the SGDMA method for transmitting or the
 * MSGDMA method, assumes no scatter/gather support,
 * implying an assumption that there's only one
 * physically contiguous fragment starting at
 * skb->data, for length of skb_headlen(skb).
 */
static netdev_tx_t tse_start_xmit(struct sk_buff *skb, struct net_device *dev)
{
        struct altera_tse_private *priv = netdev_priv(dev);
        unsigned int txsize = priv->tx_ring_size;
        unsigned int entry;
        struct tse_buffer *buffer = NULL;
        int nfrags = skb_shinfo(skb)->nr_frags;
        unsigned int nopaged_len = skb_headlen(skb);
        netdev_tx_t ret = NETDEV_TX_OK;
        dma_addr_t dma_addr;

        spin_lock_bh(&priv->tx_lock);

        if (unlikely(tse_tx_avail(priv) < nfrags + 1)) {
                if (!netif_queue_stopped(dev)) {
                        netif_stop_queue(dev);
                        /* This is a hard error, log it. */
                        netdev_err(priv->dev,
                                   "%s: Tx list full when queue awake\n",
                                   __func__);
                }
                ret = NETDEV_TX_BUSY;
                goto out;
        }

        /* Map the first skb fragment */
        entry = priv->tx_prod % txsize;
        buffer = &priv->tx_ring[entry];

        dma_addr = dma_map_single(priv->device, skb->data, nopaged_len,
                                  DMA_TO_DEVICE);
        if (dma_mapping_error(priv->device, dma_addr)) {
                netdev_err(priv->dev, "%s: DMA mapping error\n", __func__);
                ret = NETDEV_TX_OK;
                goto out;
        }

        buffer->skb = skb;
        buffer->dma_addr = dma_addr;
        buffer->len = nopaged_len;

        priv->dmaops->tx_buffer(priv, buffer);

        skb_tx_timestamp(skb);

        priv->tx_prod++;
        dev->stats.tx_bytes += skb->len;

        if (unlikely(tse_tx_avail(priv) <= TXQUEUESTOP_THRESHHOLD)) {
                if (netif_msg_hw(priv))
                        netdev_dbg(priv->dev, "%s: stop transmitted packets\n",
                                   __func__);
                netif_stop_queue(dev);
        }

out:
        spin_unlock_bh(&priv->tx_lock);

        return ret;
}

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

        /* only change config if there is a link */
        spin_lock(&priv->mac_cfg_lock);
        if (phydev->link) {
                /* Read old config */
                u32 cfg_reg = ioread32(&priv->mac_dev->command_config);

                /* Check duplex */
                if (phydev->duplex != priv->oldduplex) {
                        new_state = 1;
                        if (!(phydev->duplex))
                                cfg_reg |= MAC_CMDCFG_HD_ENA;
                        else
                                cfg_reg &= ~MAC_CMDCFG_HD_ENA;

                        netdev_dbg(priv->dev, "%s: Link duplex = 0x%x\n",
                                   dev->name, phydev->duplex);

                        priv->oldduplex = phydev->duplex;
                }

                /* Check speed */
                if (phydev->speed != priv->oldspeed) {
                        new_state = 1;
                        switch (phydev->speed) {
                        case 1000:
                                cfg_reg |= MAC_CMDCFG_ETH_SPEED;
                                cfg_reg &= ~MAC_CMDCFG_ENA_10;
                                break;
                        case 100:
                                cfg_reg &= ~MAC_CMDCFG_ETH_SPEED;
                                cfg_reg &= ~MAC_CMDCFG_ENA_10;
                                break;
                        case 10:
                                cfg_reg &= ~MAC_CMDCFG_ETH_SPEED;
                                cfg_reg |= MAC_CMDCFG_ENA_10;
                                break;
                        default:
                                if (netif_msg_link(priv))
                                        netdev_warn(dev, "Speed (%d) is not 10/100/1000!\n",
                                                    phydev->speed);
                                break;
                        }
                        priv->oldspeed = phydev->speed;
                }
                iowrite32(cfg_reg, &priv->mac_dev->command_config);

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

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

        spin_unlock(&priv->mac_cfg_lock);
}
static struct phy_device *connect_local_phy(struct net_device *dev)
{
        struct altera_tse_private *priv = netdev_priv(dev);
        struct phy_device *phydev = NULL;
        char phy_id_fmt[MII_BUS_ID_SIZE + 3];

        if (priv->phy_addr != POLL_PHY) {
                snprintf(phy_id_fmt, MII_BUS_ID_SIZE + 3, PHY_ID_FMT,
                         priv->mdio->id, priv->phy_addr);

                netdev_dbg(dev, "trying to attach to %s\n", phy_id_fmt);

                phydev = phy_connect(dev, phy_id_fmt, &altera_tse_adjust_link,
                                     priv->phy_iface);
                if (IS_ERR(phydev)) {
                        netdev_err(dev, "Could not attach to PHY\n");
                        phydev = NULL;
                }

        } else {
                int ret;
                phydev = phy_find_first(priv->mdio);
                if (phydev == NULL) {
                        netdev_err(dev, "No PHY found\n");
                        return phydev;
                }

                ret = phy_connect_direct(dev, phydev, &altera_tse_adjust_link,
                                priv->phy_iface);
                if (ret != 0) {
                        netdev_err(dev, "Could not attach to PHY\n");
                        phydev = NULL;
                }
        }
        return phydev;
}

static int altera_tse_phy_get_addr_mdio_create(struct net_device *dev)
{
        struct altera_tse_private *priv = netdev_priv(dev);
        struct device_node *np = priv->device->of_node;
        int ret;

        ret = of_get_phy_mode(np, &priv->phy_iface);

        /* Avoid get phy addr and create mdio if no phy is present */
        if (ret)
                return 0;

        /* try to get PHY address from device tree, use PHY autodetection if
         * no valid address is given
         */

        if (of_property_read_u32(priv->device->of_node, "phy-addr",
                         &priv->phy_addr)) {
                priv->phy_addr = POLL_PHY;
        }

        if (!((priv->phy_addr == POLL_PHY) ||
                  ((priv->phy_addr >= 0) && (priv->phy_addr < PHY_MAX_ADDR)))) {
                netdev_err(dev, "invalid phy-addr specified %d\n",
                        priv->phy_addr);
                return -ENODEV;
        }

        /* Create/attach to MDIO bus */
        ret = altera_tse_mdio_create(dev,
                                         atomic_add_return(1, &instance_count));

        if (ret)
                return -ENODEV;

        return 0;
}

/* Initialize driver's PHY state, and attach to the PHY
 */
static int init_phy(struct net_device *dev)
{
        struct altera_tse_private *priv = netdev_priv(dev);
        struct phy_device *phydev;
        struct device_node *phynode;
        bool fixed_link = false;
        int rc = 0;

        /* Avoid init phy in case of no phy present */
        if (!priv->phy_iface)
                return 0;

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

        phynode = of_parse_phandle(priv->device->of_node, "phy-handle", 0);

        if (!phynode) {
                /* check if a fixed-link is defined in device-tree */
                if (of_phy_is_fixed_link(priv->device->of_node)) {
                        rc = of_phy_register_fixed_link(priv->device->of_node);
                        if (rc < 0) {
                                netdev_err(dev, "cannot register fixed PHY\n");
                                return rc;
                        }

                        /* In the case of a fixed PHY, the DT node associated
                         * to the PHY is the Ethernet MAC DT node.
                         */
                        phynode = of_node_get(priv->device->of_node);
                        fixed_link = true;

                        netdev_dbg(dev, "fixed-link detected\n");
                        phydev = of_phy_connect(dev, phynode,
                                                &altera_tse_adjust_link,
                                                0, priv->phy_iface);
                } else {
                        netdev_dbg(dev, "no phy-handle found\n");
                        if (!priv->mdio) {
                                netdev_err(dev, "No phy-handle nor local mdio specified\n");
                                return -ENODEV;
                        }
                        phydev = connect_local_phy(dev);
                }
        } else {
                netdev_dbg(dev, "phy-handle found\n");
                phydev = of_phy_connect(dev, phynode,
                        &altera_tse_adjust_link, 0, priv->phy_iface);
        }
        of_node_put(phynode);

        if (!phydev) {
                netdev_err(dev, "Could not find the PHY\n");
                if (fixed_link)
                        of_phy_deregister_fixed_link(priv->device->of_node);
                return -ENODEV;
        }

        /* Stop Advertising 1000BASE Capability if interface is not GMII
         */
        if ((priv->phy_iface == PHY_INTERFACE_MODE_MII) ||
            (priv->phy_iface == PHY_INTERFACE_MODE_RMII))
                phy_set_max_speed(phydev, SPEED_100);

        /* Broken HW is sometimes missing the pull-up resistor on the
         * MDIO line, which results in reads to non-existent devices returning
         * 0 rather than 0xffff. Catch this here and treat 0 as a non-existent
         * device as well. If a fixed-link is used the phy_id is always 0.
         * Note: phydev->phy_id is the result of reading the UID PHY registers.
         */
        if ((phydev->phy_id == 0) && !fixed_link) {
                netdev_err(dev, "Bad PHY UID 0x%08x\n", phydev->phy_id);
                phy_disconnect(phydev);
                return -ENODEV;
        }

        netdev_dbg(dev, "attached to PHY %d UID 0x%08x Link = %d\n",
                   phydev->mdio.addr, phydev->phy_id, phydev->link);

        return 0;
}

static void tse_update_mac_addr(struct altera_tse_private *priv, const u8 *addr)
{
        u32 msb;
        u32 lsb;

        msb = (addr[3] << 24) | (addr[2] << 16) | (addr[1] << 8) | addr[0];
        lsb = ((addr[5] << 8) | addr[4]) & 0xffff;

        /* Set primary MAC address */
        csrwr32(msb, priv->mac_dev, tse_csroffs(mac_addr_0));
        csrwr32(lsb, priv->mac_dev, tse_csroffs(mac_addr_1));
}

/* MAC software reset.
 * When reset is triggered, the MAC function completes the current
 * transmission or reception, and subsequently disables the transmit and
 * receive logic, flushes the receive FIFO buffer, and resets the statistics
 * counters.
 */
static int reset_mac(struct altera_tse_private *priv)
{
        int counter;
        u32 dat;

        dat = csrrd32(priv->mac_dev, tse_csroffs(command_config));
        dat &= ~(MAC_CMDCFG_TX_ENA | MAC_CMDCFG_RX_ENA);
        dat |= MAC_CMDCFG_SW_RESET | MAC_CMDCFG_CNT_RESET;
        csrwr32(dat, priv->mac_dev, tse_csroffs(command_config));

        counter = 0;
        while (counter++ < ALTERA_TSE_SW_RESET_WATCHDOG_CNTR) {
                if (tse_bit_is_clear(priv->mac_dev, tse_csroffs(command_config),
                                     MAC_CMDCFG_SW_RESET))
                        break;
                udelay(1);
        }

        if (counter >= ALTERA_TSE_SW_RESET_WATCHDOG_CNTR) {
                dat = csrrd32(priv->mac_dev, tse_csroffs(command_config));
                dat &= ~MAC_CMDCFG_SW_RESET;
                csrwr32(dat, priv->mac_dev, tse_csroffs(command_config));
                return -1;
        }
        return 0;
}

/* Initialize MAC core registers
*/
static int init_mac(struct altera_tse_private *priv)
{
        unsigned int cmd = 0;
        u32 frm_length;

        /* Setup Rx FIFO */
        csrwr32(priv->rx_fifo_depth - ALTERA_TSE_RX_SECTION_EMPTY,
                priv->mac_dev, tse_csroffs(rx_section_empty));

        csrwr32(ALTERA_TSE_RX_SECTION_FULL, priv->mac_dev,
                tse_csroffs(rx_section_full));

        csrwr32(ALTERA_TSE_RX_ALMOST_EMPTY, priv->mac_dev,
                tse_csroffs(rx_almost_empty));

        csrwr32(ALTERA_TSE_RX_ALMOST_FULL, priv->mac_dev,
                tse_csroffs(rx_almost_full));

        /* Setup Tx FIFO */
        csrwr32(priv->tx_fifo_depth - ALTERA_TSE_TX_SECTION_EMPTY,
                priv->mac_dev, tse_csroffs(tx_section_empty));

        csrwr32(ALTERA_TSE_TX_SECTION_FULL, priv->mac_dev,
                tse_csroffs(tx_section_full));

        csrwr32(ALTERA_TSE_TX_ALMOST_EMPTY, priv->mac_dev,
                tse_csroffs(tx_almost_empty));

        csrwr32(ALTERA_TSE_TX_ALMOST_FULL, priv->mac_dev,
                tse_csroffs(tx_almost_full));

        /* MAC Address Configuration */
        tse_update_mac_addr(priv, priv->dev->dev_addr);

        /* MAC Function Configuration */
        frm_length = ETH_HLEN + priv->dev->mtu + ETH_FCS_LEN;
        csrwr32(frm_length, priv->mac_dev, tse_csroffs(frm_length));

        csrwr32(ALTERA_TSE_TX_IPG_LENGTH, priv->mac_dev,
                tse_csroffs(tx_ipg_length));

        /* Disable RX/TX shift 16 for alignment of all received frames on 16-bit
         * start address
         */
        tse_set_bit(priv->mac_dev, tse_csroffs(rx_cmd_stat),
                    ALTERA_TSE_RX_CMD_STAT_RX_SHIFT16);

        tse_clear_bit(priv->mac_dev, tse_csroffs(tx_cmd_stat),
                      ALTERA_TSE_TX_CMD_STAT_TX_SHIFT16 |
                      ALTERA_TSE_TX_CMD_STAT_OMIT_CRC);

        /* Set the MAC options */
        cmd = csrrd32(priv->mac_dev, tse_csroffs(command_config));
        cmd &= ~MAC_CMDCFG_PAD_EN;      /* No padding Removal on Receive */
        cmd &= ~MAC_CMDCFG_CRC_FWD;     /* CRC Removal */
        cmd |= MAC_CMDCFG_RX_ERR_DISC;  /* Automatically discard frames
                                         * with CRC errors
                                         */
        cmd |= MAC_CMDCFG_CNTL_FRM_ENA;
        cmd &= ~MAC_CMDCFG_TX_ENA;
        cmd &= ~MAC_CMDCFG_RX_ENA;

        /* Default speed and duplex setting, full/100 */
        cmd &= ~MAC_CMDCFG_HD_ENA;
        cmd &= ~MAC_CMDCFG_ETH_SPEED;
        cmd &= ~MAC_CMDCFG_ENA_10;

        csrwr32(cmd, priv->mac_dev, tse_csroffs(command_config));

        csrwr32(ALTERA_TSE_PAUSE_QUANTA, priv->mac_dev,
                tse_csroffs(pause_quanta));

        if (netif_msg_hw(priv))
                dev_dbg(priv->device,
                        "MAC post-initialization: CMD_CONFIG = 0x%08x\n", cmd);

        return 0;
}

/* Start/stop MAC transmission logic
 */
static void tse_set_mac(struct altera_tse_private *priv, bool enable)
{
        u32 value = csrrd32(priv->mac_dev, tse_csroffs(command_config));

        if (enable)
                value |= MAC_CMDCFG_TX_ENA | MAC_CMDCFG_RX_ENA;
        else
                value &= ~(MAC_CMDCFG_TX_ENA | MAC_CMDCFG_RX_ENA);

        csrwr32(value, priv->mac_dev, tse_csroffs(command_config));
}

/* Change the MTU
 */
static int tse_change_mtu(struct net_device *dev, int new_mtu)
{

        if (netif_running(dev)) {
                netdev_err(dev, "must be stopped to change its MTU\n");
                return -EBUSY;
        }

        dev->mtu = new_mtu;
        netdev_update_features(dev);

        return 0;
}

static void altera_tse_set_mcfilter(struct net_device *dev)
{
        struct altera_tse_private *priv = netdev_priv(dev);
        int i;
        struct netdev_hw_addr *ha;

        /* clear the hash filter */
        for (i = 0; i < 64; i++)
                csrwr32(0, priv->mac_dev, tse_csroffs(hash_table) + i * 4);

        netdev_for_each_mc_addr(ha, dev) {
                unsigned int hash = 0;
                int mac_octet;

                for (mac_octet = 5; mac_octet >= 0; mac_octet--) {
                        unsigned char xor_bit = 0;
                        unsigned char octet = ha->addr[mac_octet];
                        unsigned int bitshift;

                        for (bitshift = 0; bitshift < 8; bitshift++)
                                xor_bit ^= ((octet >> bitshift) & 0x01);

                        hash = (hash << 1) | xor_bit;
                }
                csrwr32(1, priv->mac_dev, tse_csroffs(hash_table) + hash * 4);
        }
}


static void altera_tse_set_mcfilterall(struct net_device *dev)
{
        struct altera_tse_private *priv = netdev_priv(dev);
        int i;

        /* set the hash filter */
        for (i = 0; i < 64; i++)
                csrwr32(1, priv->mac_dev, tse_csroffs(hash_table) + i * 4);
}

/* Set or clear the multicast filter for this adapter
 */
static void tse_set_rx_mode_hashfilter(struct net_device *dev)
{
        struct altera_tse_private *priv = netdev_priv(dev);

        spin_lock(&priv->mac_cfg_lock);

        if (dev->flags & IFF_PROMISC)
                tse_set_bit(priv->mac_dev, tse_csroffs(command_config),
                            MAC_CMDCFG_PROMIS_EN);

        if (dev->flags & IFF_ALLMULTI)
                altera_tse_set_mcfilterall(dev);
        else
                altera_tse_set_mcfilter(dev);

        spin_unlock(&priv->mac_cfg_lock);
}

/* Set or clear the multicast filter for this adapter
 */
static void tse_set_rx_mode(struct net_device *dev)
{
        struct altera_tse_private *priv = netdev_priv(dev);

        spin_lock(&priv->mac_cfg_lock);

        if ((dev->flags & IFF_PROMISC) || (dev->flags & IFF_ALLMULTI) ||
            !netdev_mc_empty(dev) || !netdev_uc_empty(dev))
                tse_set_bit(priv->mac_dev, tse_csroffs(command_config),
                            MAC_CMDCFG_PROMIS_EN);
        else
                tse_clear_bit(priv->mac_dev, tse_csroffs(command_config),
                              MAC_CMDCFG_PROMIS_EN);

        spin_unlock(&priv->mac_cfg_lock);
}

/* Initialise (if necessary) the SGMII PCS component
 */
static int init_sgmii_pcs(struct net_device *dev)
{
        struct altera_tse_private *priv = netdev_priv(dev);
        int n;
        unsigned int tmp_reg = 0;

        if (priv->phy_iface != PHY_INTERFACE_MODE_SGMII)
                return 0; /* Nothing to do, not in SGMII mode */

        /* The TSE SGMII PCS block looks a little like a PHY, it is
         * mapped into the zeroth MDIO space of the MAC and it has
         * ID registers like a PHY would.  Sadly this is often
         * configured to zeroes, so don't be surprised if it does
         * show 0x00000000.
         */

        if (sgmii_pcs_scratch_test(priv, 0x0000) &&
                sgmii_pcs_scratch_test(priv, 0xffff) &&
                sgmii_pcs_scratch_test(priv, 0xa5a5) &&
                sgmii_pcs_scratch_test(priv, 0x5a5a)) {
                netdev_info(dev, "PCS PHY ID: 0x%04x%04x\n",
                                sgmii_pcs_read(priv, MII_PHYSID1),
                                sgmii_pcs_read(priv, MII_PHYSID2));
        } else {
                netdev_err(dev, "SGMII PCS Scratch memory test failed.\n");
                return -ENOMEM;
        }

        /* Starting on page 5-29 of the MegaCore Function User Guide
         * Set SGMII Link timer to 1.6ms
         */
        sgmii_pcs_write(priv, SGMII_PCS_LINK_TIMER_0, 0x0D40);
        sgmii_pcs_write(priv, SGMII_PCS_LINK_TIMER_1, 0x03);

        /* Enable SGMII Interface and Enable SGMII Auto Negotiation */
        sgmii_pcs_write(priv, SGMII_PCS_IF_MODE, 0x3);

        /* Enable Autonegotiation */
        tmp_reg = sgmii_pcs_read(priv, MII_BMCR);
        tmp_reg |= (BMCR_SPEED1000 | BMCR_FULLDPLX | BMCR_ANENABLE);
        sgmii_pcs_write(priv, MII_BMCR, tmp_reg);

        /* Reset PCS block */
        tmp_reg |= BMCR_RESET;
        sgmii_pcs_write(priv, MII_BMCR, tmp_reg);
        for (n = 0; n < SGMII_PCS_SW_RESET_TIMEOUT; n++) {
                if (!(sgmii_pcs_read(priv, MII_BMCR) & BMCR_RESET)) {
                        netdev_info(dev, "SGMII PCS block initialised OK\n");
                        return 0;
                }
                udelay(1);
        }

        /* We failed to reset the block, return a timeout */
        netdev_err(dev, "SGMII PCS block reset failed.\n");
        return -ETIMEDOUT;
}

/* Open and initialize the interface
 */
static int tse_open(struct net_device *dev)
{
        struct altera_tse_private *priv = netdev_priv(dev);
        int ret = 0;
        int i;
        unsigned long int flags;

        /* Reset and configure TSE MAC and probe associated PHY */
        ret = priv->dmaops->init_dma(priv);
        if (ret != 0) {
                netdev_err(dev, "Cannot initialize DMA\n");
                goto phy_error;
        }

        if (netif_msg_ifup(priv))
                netdev_warn(dev, "device MAC address %pM\n",
                            dev->dev_addr);

        if ((priv->revision < 0xd00) || (priv->revision > 0xe00))
                netdev_warn(dev, "TSE revision %x\n", priv->revision);

        spin_lock(&priv->mac_cfg_lock);
        /* no-op if MAC not operating in SGMII mode*/
        ret = init_sgmii_pcs(dev);
        if (ret) {
                netdev_err(dev,
                           "Cannot init the SGMII PCS (error: %d)\n", ret);
                spin_unlock(&priv->mac_cfg_lock);
                goto phy_error;
        }

        ret = reset_mac(priv);
        /* Note that reset_mac will fail if the clocks are gated by the PHY
         * due to the PHY being put into isolation or power down mode.
         * This is not an error if reset fails due to no clock.
         */
        if (ret)
                netdev_dbg(dev, "Cannot reset MAC core (error: %d)\n", ret);

        ret = init_mac(priv);
        spin_unlock(&priv->mac_cfg_lock);
        if (ret) {
                netdev_err(dev, "Cannot init MAC core (error: %d)\n", ret);
                goto alloc_skbuf_error;
        }

        priv->dmaops->reset_dma(priv);

        /* Create and initialize the TX/RX descriptors chains. */
        priv->rx_ring_size = dma_rx_num;
        priv->tx_ring_size = dma_tx_num;
        ret = alloc_init_skbufs(priv);
        if (ret) {
                netdev_err(dev, "DMA descriptors initialization failed\n");
                goto alloc_skbuf_error;
        }


        /* Register RX interrupt */
        ret = request_irq(priv->rx_irq, altera_isr, IRQF_SHARED,
                          dev->name, dev);
        if (ret) {
                netdev_err(dev, "Unable to register RX interrupt %d\n",
                           priv->rx_irq);
                goto init_error;
        }

        /* Register TX interrupt */
        ret = request_irq(priv->tx_irq, altera_isr, IRQF_SHARED,
                          dev->name, dev);
        if (ret) {
                netdev_err(dev, "Unable to register TX interrupt %d\n",
                           priv->tx_irq);
                goto tx_request_irq_error;
        }

        /* Enable DMA interrupts */
        spin_lock_irqsave(&priv->rxdma_irq_lock, flags);
        priv->dmaops->enable_rxirq(priv);
        priv->dmaops->enable_txirq(priv);

        /* Setup RX descriptor chain */
        for (i = 0; i < priv->rx_ring_size; i++)
                priv->dmaops->add_rx_desc(priv, &priv->rx_ring[i]);

        spin_unlock_irqrestore(&priv->rxdma_irq_lock, flags);

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

        napi_enable(&priv->napi);
        netif_start_queue(dev);

        priv->dmaops->start_rxdma(priv);

        /* Start MAC Rx/Tx */
        spin_lock(&priv->mac_cfg_lock);
        tse_set_mac(priv, true);
        spin_unlock(&priv->mac_cfg_lock);

        return 0;

tx_request_irq_error:
        free_irq(priv->rx_irq, dev);
init_error:
        free_skbufs(dev);
alloc_skbuf_error:
phy_error:
        return ret;
}

/* Stop TSE MAC interface and put the device in an inactive state
 */
static int tse_shutdown(struct net_device *dev)
{
        struct altera_tse_private *priv = netdev_priv(dev);
        int ret;
        unsigned long int flags;

        /* Stop the PHY */
        if (dev->phydev)
                phy_stop(dev->phydev);

        netif_stop_queue(dev);
        napi_disable(&priv->napi);

        /* Disable DMA interrupts */
        spin_lock_irqsave(&priv->rxdma_irq_lock, flags);
        priv->dmaops->disable_rxirq(priv);
        priv->dmaops->disable_txirq(priv);
        spin_unlock_irqrestore(&priv->rxdma_irq_lock, flags);

        /* Free the IRQ lines */
        free_irq(priv->rx_irq, dev);
        free_irq(priv->tx_irq, dev);

        /* disable and reset the MAC, empties fifo */
        spin_lock(&priv->mac_cfg_lock);
        spin_lock(&priv->tx_lock);

        ret = reset_mac(priv);
        /* Note that reset_mac will fail if the clocks are gated by the PHY
         * due to the PHY being put into isolation or power down mode.
         * This is not an error if reset fails due to no clock.
         */
        if (ret)
                netdev_dbg(dev, "Cannot reset MAC core (error: %d)\n", ret);
        priv->dmaops->reset_dma(priv);
        free_skbufs(dev);

        spin_unlock(&priv->tx_lock);
        spin_unlock(&priv->mac_cfg_lock);

        priv->dmaops->uninit_dma(priv);

        return 0;
}

static struct net_device_ops altera_tse_netdev_ops = {
        .ndo_open               = tse_open,
        .ndo_stop               = tse_shutdown,
        .ndo_start_xmit         = tse_start_xmit,
        .ndo_set_mac_address    = eth_mac_addr,
        .ndo_set_rx_mode        = tse_set_rx_mode,
        .ndo_change_mtu         = tse_change_mtu,
        .ndo_validate_addr      = eth_validate_addr,
};

static int request_and_map(struct platform_device *pdev, const char *name,
                           struct resource **res, void __iomem **ptr)
{
        struct resource *region;
        struct device *device = &pdev->dev;

        *res = platform_get_resource_byname(pdev, IORESOURCE_MEM, name);
        if (*res == NULL) {
                dev_err(device, "resource %s not defined\n", name);
                return -ENODEV;
        }

        region = devm_request_mem_region(device, (*res)->start,
                                         resource_size(*res), dev_name(device));
        if (region == NULL) {
                dev_err(device, "unable to request %s\n", name);
                return -EBUSY;
        }

        *ptr = devm_ioremap(device, region->start,
                                    resource_size(region));
        if (*ptr == NULL) {
                dev_err(device, "ioremap of %s failed!", name);
                return -ENOMEM;
        }

        return 0;
}

/* Probe Altera TSE MAC device
 */
static int altera_tse_probe(struct platform_device *pdev)
{
        struct net_device *ndev;
        int ret = -ENODEV;
        struct resource *control_port;
        struct resource *dma_res;
        struct altera_tse_private *priv;
        void __iomem *descmap;
        const struct of_device_id *of_id = NULL;

        ndev = alloc_etherdev(sizeof(struct altera_tse_private));
        if (!ndev) {
                dev_err(&pdev->dev, "Could not allocate network device\n");
                return -ENODEV;
        }

        SET_NETDEV_DEV(ndev, &pdev->dev);

        priv = netdev_priv(ndev);
        priv->device = &pdev->dev;
        priv->dev = ndev;
        priv->msg_enable = netif_msg_init(debug, default_msg_level);

        of_id = of_match_device(altera_tse_ids, &pdev->dev);

        if (of_id)
                priv->dmaops = (struct altera_dmaops *)of_id->data;


        if (priv->dmaops &&
            priv->dmaops->altera_dtype == ALTERA_DTYPE_SGDMA) {
                /* Get the mapped address to the SGDMA descriptor memory */
                ret = request_and_map(pdev, "s1", &dma_res, &descmap);
                if (ret)
                        goto err_free_netdev;

                /* Start of that memory is for transmit descriptors */
                priv->tx_dma_desc = descmap;

                /* First half is for tx descriptors, other half for tx */
                priv->txdescmem = resource_size(dma_res)/2;

                priv->txdescmem_busaddr = (dma_addr_t)dma_res->start;

                priv->rx_dma_desc = (void __iomem *)((uintptr_t)(descmap +
                                                     priv->txdescmem));
                priv->rxdescmem = resource_size(dma_res)/2;
                priv->rxdescmem_busaddr = dma_res->start;
                priv->rxdescmem_busaddr += priv->txdescmem;

                if (upper_32_bits(priv->rxdescmem_busaddr)) {
                        dev_dbg(priv->device,
                                "SGDMA bus addresses greater than 32-bits\n");
                        ret = -EINVAL;
                        goto err_free_netdev;
                }
                if (upper_32_bits(priv->txdescmem_busaddr)) {
                        dev_dbg(priv->device,
                                "SGDMA bus addresses greater than 32-bits\n");
                        ret = -EINVAL;
                        goto err_free_netdev;
                }
        } else if (priv->dmaops &&
                   priv->dmaops->altera_dtype == ALTERA_DTYPE_MSGDMA) {
                ret = request_and_map(pdev, "rx_resp", &dma_res,
                                      &priv->rx_dma_resp);
                if (ret)
                        goto err_free_netdev;

                ret = request_and_map(pdev, "tx_desc", &dma_res,
                                      &priv->tx_dma_desc);
                if (ret)
                        goto err_free_netdev;

                priv->txdescmem = resource_size(dma_res);
                priv->txdescmem_busaddr = dma_res->start;

                ret = request_and_map(pdev, "rx_desc", &dma_res,
                                      &priv->rx_dma_desc);
                if (ret)
                        goto err_free_netdev;

                priv->rxdescmem = resource_size(dma_res);
                priv->rxdescmem_busaddr = dma_res->start;

        } else {
                ret = -ENODEV;
                goto err_free_netdev;
        }

        if (!dma_set_mask(priv->device, DMA_BIT_MASK(priv->dmaops->dmamask))) {
                dma_set_coherent_mask(priv->device,
                                      DMA_BIT_MASK(priv->dmaops->dmamask));
        } else if (!dma_set_mask(priv->device, DMA_BIT_MASK(32))) {
                dma_set_coherent_mask(priv->device, DMA_BIT_MASK(32));
        } else {
                ret = -EIO;
                goto err_free_netdev;
        }

        /* MAC address space */
        ret = request_and_map(pdev, "control_port", &control_port,
                              (void __iomem **)&priv->mac_dev);
        if (ret)
                goto err_free_netdev;

        /* xSGDMA Rx Dispatcher address space */
        ret = request_and_map(pdev, "rx_csr", &dma_res,
                              &priv->rx_dma_csr);
        if (ret)
                goto err_free_netdev;


        /* xSGDMA Tx Dispatcher address space */
        ret = request_and_map(pdev, "tx_csr", &dma_res,
                              &priv->tx_dma_csr);
        if (ret)
                goto err_free_netdev;


        /* Rx IRQ */
        priv->rx_irq = platform_get_irq_byname(pdev, "rx_irq");
        if (priv->rx_irq == -ENXIO) {
                dev_err(&pdev->dev, "cannot obtain Rx IRQ\n");
                ret = -ENXIO;
                goto err_free_netdev;
        }

        /* Tx IRQ */
        priv->tx_irq = platform_get_irq_byname(pdev, "tx_irq");
        if (priv->tx_irq == -ENXIO) {
                dev_err(&pdev->dev, "cannot obtain Tx IRQ\n");
                ret = -ENXIO;
                goto err_free_netdev;
        }

        /* get FIFO depths from device tree */
        if (of_property_read_u32(pdev->dev.of_node, "rx-fifo-depth",
                                 &priv->rx_fifo_depth)) {
                dev_err(&pdev->dev, "cannot obtain rx-fifo-depth\n");
                ret = -ENXIO;
                goto err_free_netdev;
        }

        if (of_property_read_u32(pdev->dev.of_node, "tx-fifo-depth",
                                 &priv->tx_fifo_depth)) {
                dev_err(&pdev->dev, "cannot obtain tx-fifo-depth\n");
                ret = -ENXIO;
                goto err_free_netdev;
        }

        /* get hash filter settings for this instance */
        priv->hash_filter =
                of_property_read_bool(pdev->dev.of_node,
                                      "altr,has-hash-multicast-filter");

        /* Set hash filter to not set for now until the
         * multicast filter receive issue is debugged
         */
        priv->hash_filter = 0;

        /* get supplemental address settings for this instance */
        priv->added_unicast =
                of_property_read_bool(pdev->dev.of_node,
                                      "altr,has-supplementary-unicast");

        priv->dev->min_mtu = ETH_ZLEN + ETH_FCS_LEN;
        /* Max MTU is 1500, ETH_DATA_LEN */
        priv->dev->max_mtu = ETH_DATA_LEN;

        /* Get the max mtu from the device tree. Note that the
         * "max-frame-size" parameter is actually max mtu. Definition
         * in the ePAPR v1.1 spec and usage differ, so go with usage.
         */
        of_property_read_u32(pdev->dev.of_node, "max-frame-size",
                             &priv->dev->max_mtu);

        /* The DMA buffer size already accounts for an alignment bias
         * to avoid unaligned access exceptions for the NIOS processor,
         */
        priv->rx_dma_buf_sz = ALTERA_RXDMABUFFER_SIZE;

        /* get default MAC address from device tree */
        ret = of_get_ethdev_address(pdev->dev.of_node, ndev);
        if (ret)
                eth_hw_addr_random(ndev);

        /* get phy addr and create mdio */
        ret = altera_tse_phy_get_addr_mdio_create(ndev);

        if (ret)
                goto err_free_netdev;

        /* initialize netdev */
        ndev->mem_start = control_port->start;
        ndev->mem_end = control_port->end;
        ndev->netdev_ops = &altera_tse_netdev_ops;
        altera_tse_set_ethtool_ops(ndev);

        altera_tse_netdev_ops.ndo_set_rx_mode = tse_set_rx_mode;

        if (priv->hash_filter)
                altera_tse_netdev_ops.ndo_set_rx_mode =
                        tse_set_rx_mode_hashfilter;

        /* Scatter/gather IO is not supported,
         * so it is turned off
         */
        ndev->hw_features &= ~NETIF_F_SG;
        ndev->features |= ndev->hw_features | NETIF_F_HIGHDMA;

        /* VLAN offloading of tagging, stripping and filtering is not
         * supported by hardware, but driver will accommodate the
         * extra 4-byte VLAN tag for processing by upper layers
         */
        ndev->features |= NETIF_F_HW_VLAN_CTAG_RX;

        /* setup NAPI interface */
        netif_napi_add(ndev, &priv->napi, tse_poll, NAPI_POLL_WEIGHT);

        spin_lock_init(&priv->mac_cfg_lock);
        spin_lock_init(&priv->tx_lock);
        spin_lock_init(&priv->rxdma_irq_lock);

        netif_carrier_off(ndev);
        ret = register_netdev(ndev);
        if (ret) {
                dev_err(&pdev->dev, "failed to register TSE net device\n");
                goto err_register_netdev;
        }

        platform_set_drvdata(pdev, ndev);

        priv->revision = ioread32(&priv->mac_dev->megacore_revision);

        if (netif_msg_probe(priv))
                dev_info(&pdev->dev, "Altera TSE MAC version %d.%d at 0x%08lx irq %d/%d\n",
                         (priv->revision >> 8) & 0xff,
                         priv->revision & 0xff,
                         (unsigned long) control_port->start, priv->rx_irq,
                         priv->tx_irq);

        ret = init_phy(ndev);
        if (ret != 0) {
                netdev_err(ndev, "Cannot attach to PHY (error: %d)\n", ret);
                goto err_init_phy;
        }
        return 0;

err_init_phy:
        unregister_netdev(ndev);
err_register_netdev:
        netif_napi_del(&priv->napi);
        altera_tse_mdio_destroy(ndev);
err_free_netdev:
        free_netdev(ndev);
        return ret;
}

/* Remove Altera TSE MAC device
 */
static int altera_tse_remove(struct platform_device *pdev)
{
        struct net_device *ndev = platform_get_drvdata(pdev);
        struct altera_tse_private *priv = netdev_priv(ndev);

        if (ndev->phydev) {
                phy_disconnect(ndev->phydev);

                if (of_phy_is_fixed_link(priv->device->of_node))
                        of_phy_deregister_fixed_link(priv->device->of_node);
        }

        platform_set_drvdata(pdev, NULL);
        altera_tse_mdio_destroy(ndev);
        unregister_netdev(ndev);
        free_netdev(ndev);

        return 0;
}

static const struct altera_dmaops altera_dtype_sgdma = {
        .altera_dtype = ALTERA_DTYPE_SGDMA,
        .dmamask = 32,
        .reset_dma = sgdma_reset,
        .enable_txirq = sgdma_enable_txirq,
        .enable_rxirq = sgdma_enable_rxirq,
        .disable_txirq = sgdma_disable_txirq,
        .disable_rxirq = sgdma_disable_rxirq,
        .clear_txirq = sgdma_clear_txirq,
        .clear_rxirq = sgdma_clear_rxirq,
        .tx_buffer = sgdma_tx_buffer,
        .tx_completions = sgdma_tx_completions,
        .add_rx_desc = sgdma_add_rx_desc,
        .get_rx_status = sgdma_rx_status,
        .init_dma = sgdma_initialize,
        .uninit_dma = sgdma_uninitialize,
        .start_rxdma = sgdma_start_rxdma,
};

static const struct altera_dmaops altera_dtype_msgdma = {
        .altera_dtype = ALTERA_DTYPE_MSGDMA,
        .dmamask = 64,
        .reset_dma = msgdma_reset,
        .enable_txirq = msgdma_enable_txirq,
        .enable_rxirq = msgdma_enable_rxirq,
        .disable_txirq = msgdma_disable_txirq,
        .disable_rxirq = msgdma_disable_rxirq,
        .clear_txirq = msgdma_clear_txirq,
        .clear_rxirq = msgdma_clear_rxirq,
        .tx_buffer = msgdma_tx_buffer,
        .tx_completions = msgdma_tx_completions,
        .add_rx_desc = msgdma_add_rx_desc,
        .get_rx_status = msgdma_rx_status,
        .init_dma = msgdma_initialize,
        .uninit_dma = msgdma_uninitialize,
        .start_rxdma = msgdma_start_rxdma,
};

static const struct of_device_id altera_tse_ids[] = {
        { .compatible = "altr,tse-msgdma-1.0", .data = &altera_dtype_msgdma, },
        { .compatible = "altr,tse-1.0", .data = &altera_dtype_sgdma, },
        { .compatible = "ALTR,tse-1.0", .data = &altera_dtype_sgdma, },
        {},
};
MODULE_DEVICE_TABLE(of, altera_tse_ids);

static struct platform_driver altera_tse_driver = {
        .probe          = altera_tse_probe,
        .remove         = altera_tse_remove,
        .suspend        = NULL,
        .resume         = NULL,
        .driver         = {
                .name   = ALTERA_TSE_RESOURCE_NAME,
                .of_match_table = altera_tse_ids,
        },
};

module_platform_driver(altera_tse_driver);

MODULE_AUTHOR("Altera Corporation");
MODULE_DESCRIPTION("Altera Triple Speed Ethernet MAC driver");
MODULE_LICENSE("GPL v2");