/*
 * Driver for Marvell Discovery (MV643XX) and Marvell Orion ethernet ports
 * Copyright (C) 2002 Matthew Dharm <mdharm@momenco.com>
 *
 * Based on the 64360 driver from:
 * Copyright (C) 2002 Rabeeh Khoury <rabeeh@galileo.co.il>
 *                    Rabeeh Khoury <rabeeh@marvell.com>
 *
 * Copyright (C) 2003 PMC-Sierra, Inc.,
 *      written by Manish Lachwani
 *
 * Copyright (C) 2003 Ralf Baechle <ralf@linux-mips.org>
 *
 * Copyright (C) 2004-2006 MontaVista Software, Inc.
 *                         Dale Farnsworth <dale@farnsworth.org>
 *
 * Copyright (C) 2004 Steven J. Hill <sjhill1@rockwellcollins.com>
 *                                   <sjhill@realitydiluted.com>
 *
 * Copyright (C) 2007-2008 Marvell Semiconductor
 *                         Lennert Buytenhek <buytenh@marvell.com>
 *
 * Copyright (C) 2013 Michael Stapelberg <michael@stapelberg.de>
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see <http://www.gnu.org/licenses/>.
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#include <linux/init.h>
#include <linux/dma-mapping.h>
#include <linux/in.h>
#include <linux/ip.h>
#include <net/tso.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#include <linux/etherdevice.h>
#include <linux/delay.h>
#include <linux/ethtool.h>
#include <linux/platform_device.h>
#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include <linux/phy.h>
#include <linux/mv643xx_eth.h>
#include <linux/io.h>
#include <linux/interrupt.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/clk.h>
#include <linux/of.h>
#include <linux/of_irq.h>
#include <linux/of_net.h>
#include <linux/of_mdio.h>

static char mv643xx_eth_driver_name[] = "mv643xx_eth";
static char mv643xx_eth_driver_version[] = "1.4";


/*
 * Registers shared between all ports.
 */
#define PHY_ADDR                        0x0000
#define WINDOW_BASE(w)                  (0x0200 + ((w) << 3))
#define WINDOW_SIZE(w)                  (0x0204 + ((w) << 3))
#define WINDOW_REMAP_HIGH(w)            (0x0280 + ((w) << 2))
#define WINDOW_BAR_ENABLE               0x0290
#define WINDOW_PROTECT(w)               (0x0294 + ((w) << 4))

/*
 * Main per-port registers.  These live at offset 0x0400 for
 * port #0, 0x0800 for port #1, and 0x0c00 for port #2.
 */
#define PORT_CONFIG                     0x0000
#define  UNICAST_PROMISCUOUS_MODE       0x00000001
#define PORT_CONFIG_EXT                 0x0004
#define MAC_ADDR_LOW                    0x0014
#define MAC_ADDR_HIGH                   0x0018
#define SDMA_CONFIG                     0x001c
#define  TX_BURST_SIZE_16_64BIT         0x01000000
#define  TX_BURST_SIZE_4_64BIT          0x00800000
#define  BLM_TX_NO_SWAP                 0x00000020
#define  BLM_RX_NO_SWAP                 0x00000010
#define  RX_BURST_SIZE_16_64BIT         0x00000008
#define  RX_BURST_SIZE_4_64BIT          0x00000004
#define PORT_SERIAL_CONTROL             0x003c
#define  SET_MII_SPEED_TO_100           0x01000000
#define  SET_GMII_SPEED_TO_1000         0x00800000
#define  SET_FULL_DUPLEX_MODE           0x00200000
#define  MAX_RX_PACKET_9700BYTE         0x000a0000
#define  DISABLE_AUTO_NEG_SPEED_GMII    0x00002000
#define  DO_NOT_FORCE_LINK_FAIL         0x00000400
#define  SERIAL_PORT_CONTROL_RESERVED   0x00000200
#define  DISABLE_AUTO_NEG_FOR_FLOW_CTRL 0x00000008
#define  DISABLE_AUTO_NEG_FOR_DUPLEX    0x00000004
#define  FORCE_LINK_PASS                0x00000002
#define  SERIAL_PORT_ENABLE             0x00000001
#define PORT_STATUS                     0x0044
#define  TX_FIFO_EMPTY                  0x00000400
#define  TX_IN_PROGRESS                 0x00000080
#define  PORT_SPEED_MASK                0x00000030
#define  PORT_SPEED_1000                0x00000010
#define  PORT_SPEED_100                 0x00000020
#define  PORT_SPEED_10                  0x00000000
#define  FLOW_CONTROL_ENABLED           0x00000008
#define  FULL_DUPLEX                    0x00000004
#define  LINK_UP                        0x00000002
#define TXQ_COMMAND                     0x0048
#define TXQ_FIX_PRIO_CONF               0x004c
#define PORT_SERIAL_CONTROL1            0x004c
#define  CLK125_BYPASS_EN               0x00000010
#define TX_BW_RATE                      0x0050
#define TX_BW_MTU                       0x0058
#define TX_BW_BURST                     0x005c
#define INT_CAUSE                       0x0060
#define  INT_TX_END                     0x07f80000
#define  INT_TX_END_0                   0x00080000
#define  INT_RX                         0x000003fc
#define  INT_RX_0                       0x00000004
#define  INT_EXT                        0x00000002
#define INT_CAUSE_EXT                   0x0064
#define  INT_EXT_LINK_PHY               0x00110000
#define  INT_EXT_TX                     0x000000ff
#define INT_MASK                        0x0068
#define INT_MASK_EXT                    0x006c
#define TX_FIFO_URGENT_THRESHOLD        0x0074
#define RX_DISCARD_FRAME_CNT            0x0084
#define RX_OVERRUN_FRAME_CNT            0x0088
#define TXQ_FIX_PRIO_CONF_MOVED         0x00dc
#define TX_BW_RATE_MOVED                0x00e0
#define TX_BW_MTU_MOVED                 0x00e8
#define TX_BW_BURST_MOVED               0x00ec
#define RXQ_CURRENT_DESC_PTR(q)         (0x020c + ((q) << 4))
#define RXQ_COMMAND                     0x0280
#define TXQ_CURRENT_DESC_PTR(q)         (0x02c0 + ((q) << 2))
#define TXQ_BW_TOKENS(q)                (0x0300 + ((q) << 4))
#define TXQ_BW_CONF(q)                  (0x0304 + ((q) << 4))
#define TXQ_BW_WRR_CONF(q)              (0x0308 + ((q) << 4))

/*
 * Misc per-port registers.
 */
#define MIB_COUNTERS(p)                 (0x1000 + ((p) << 7))
#define SPECIAL_MCAST_TABLE(p)          (0x1400 + ((p) << 10))
#define OTHER_MCAST_TABLE(p)            (0x1500 + ((p) << 10))
#define UNICAST_TABLE(p)                (0x1600 + ((p) << 10))


/*
 * SDMA configuration register default value.
 */
#if defined(__BIG_ENDIAN)
#define PORT_SDMA_CONFIG_DEFAULT_VALUE          \
                (RX_BURST_SIZE_4_64BIT  |       \
                 TX_BURST_SIZE_4_64BIT)
#elif defined(__LITTLE_ENDIAN)
#define PORT_SDMA_CONFIG_DEFAULT_VALUE          \
                (RX_BURST_SIZE_4_64BIT  |       \
                 BLM_RX_NO_SWAP         |       \
                 BLM_TX_NO_SWAP         |       \
                 TX_BURST_SIZE_4_64BIT)
#else
#error One of __BIG_ENDIAN or __LITTLE_ENDIAN must be defined
#endif


/*
 * Misc definitions.
 */
#define DEFAULT_RX_QUEUE_SIZE   128
#define DEFAULT_TX_QUEUE_SIZE   512
#define SKB_DMA_REALIGN         ((PAGE_SIZE - NET_SKB_PAD) % SMP_CACHE_BYTES)

#define TSO_HEADER_SIZE         128

/* Max number of allowed TCP segments for software TSO */
#define MV643XX_MAX_TSO_SEGS 100
#define MV643XX_MAX_SKB_DESCS (MV643XX_MAX_TSO_SEGS * 2 + MAX_SKB_FRAGS)

#define IS_TSO_HEADER(txq, addr) \
        ((addr >= txq->tso_hdrs_dma) && \
         (addr < txq->tso_hdrs_dma + txq->tx_ring_size * TSO_HEADER_SIZE))

#define DESC_DMA_MAP_SINGLE 0
#define DESC_DMA_MAP_PAGE 1

/*
 * RX/TX descriptors.
 */
#if defined(__BIG_ENDIAN)
struct rx_desc {
        u16 byte_cnt;           /* Descriptor buffer byte count         */
        u16 buf_size;           /* Buffer size                          */
        u32 cmd_sts;            /* Descriptor command status            */
        u32 next_desc_ptr;      /* Next descriptor pointer              */
        u32 buf_ptr;            /* Descriptor buffer pointer            */
};

struct tx_desc {
        u16 byte_cnt;           /* buffer byte count                    */
        u16 l4i_chk;            /* CPU provided TCP checksum            */
        u32 cmd_sts;            /* Command/status field                 */
        u32 next_desc_ptr;      /* Pointer to next descriptor           */
        u32 buf_ptr;            /* pointer to buffer for this descriptor*/
};
#elif defined(__LITTLE_ENDIAN)
struct rx_desc {
        u32 cmd_sts;            /* Descriptor command status            */
        u16 buf_size;           /* Buffer size                          */
        u16 byte_cnt;           /* Descriptor buffer byte count         */
        u32 buf_ptr;            /* Descriptor buffer pointer            */
        u32 next_desc_ptr;      /* Next descriptor pointer              */
};

struct tx_desc {
        u32 cmd_sts;            /* Command/status field                 */
        u16 l4i_chk;            /* CPU provided TCP checksum            */
        u16 byte_cnt;           /* buffer byte count                    */
        u32 buf_ptr;            /* pointer to buffer for this descriptor*/
        u32 next_desc_ptr;      /* Pointer to next descriptor           */
};
#else
#error One of __BIG_ENDIAN or __LITTLE_ENDIAN must be defined
#endif

/* RX & TX descriptor command */
#define BUFFER_OWNED_BY_DMA             0x80000000

/* RX & TX descriptor status */
#define ERROR_SUMMARY                   0x00000001

/* RX descriptor status */
#define LAYER_4_CHECKSUM_OK             0x40000000
#define RX_ENABLE_INTERRUPT             0x20000000
#define RX_FIRST_DESC                   0x08000000
#define RX_LAST_DESC                    0x04000000
#define RX_IP_HDR_OK                    0x02000000
#define RX_PKT_IS_IPV4                  0x01000000
#define RX_PKT_IS_ETHERNETV2            0x00800000
#define RX_PKT_LAYER4_TYPE_MASK         0x00600000
#define RX_PKT_LAYER4_TYPE_TCP_IPV4     0x00000000
#define RX_PKT_IS_VLAN_TAGGED           0x00080000

/* TX descriptor command */
#define TX_ENABLE_INTERRUPT             0x00800000
#define GEN_CRC                         0x00400000
#define TX_FIRST_DESC                   0x00200000
#define TX_LAST_DESC                    0x00100000
#define ZERO_PADDING                    0x00080000
#define GEN_IP_V4_CHECKSUM              0x00040000
#define GEN_TCP_UDP_CHECKSUM            0x00020000
#define UDP_FRAME                       0x00010000
#define MAC_HDR_EXTRA_4_BYTES           0x00008000
#define GEN_TCP_UDP_CHK_FULL            0x00000400
#define MAC_HDR_EXTRA_8_BYTES           0x00000200

#define TX_IHL_SHIFT                    11


/* global *******************************************************************/
struct mv643xx_eth_shared_private {
        /*
         * Ethernet controller base address.
         */
        void __iomem *base;

        /*
         * Per-port MBUS window access register value.
         */
        u32 win_protect;

        /*
         * Hardware-specific parameters.
         */
        int extended_rx_coal_limit;
        int tx_bw_control;
        int tx_csum_limit;
        struct clk *clk;
};

#define TX_BW_CONTROL_ABSENT            0
#define TX_BW_CONTROL_OLD_LAYOUT        1
#define TX_BW_CONTROL_NEW_LAYOUT        2

static int mv643xx_eth_open(struct net_device *dev);
static int mv643xx_eth_stop(struct net_device *dev);


/* per-port *****************************************************************/
struct mib_counters {
        u64 good_octets_received;
        u32 bad_octets_received;
        u32 internal_mac_transmit_err;
        u32 good_frames_received;
        u32 bad_frames_received;
        u32 broadcast_frames_received;
        u32 multicast_frames_received;
        u32 frames_64_octets;
        u32 frames_65_to_127_octets;
        u32 frames_128_to_255_octets;
        u32 frames_256_to_511_octets;
        u32 frames_512_to_1023_octets;
        u32 frames_1024_to_max_octets;
        u64 good_octets_sent;
        u32 good_frames_sent;
        u32 excessive_collision;
        u32 multicast_frames_sent;
        u32 broadcast_frames_sent;
        u32 unrec_mac_control_received;
        u32 fc_sent;
        u32 good_fc_received;
        u32 bad_fc_received;
        u32 undersize_received;
        u32 fragments_received;
        u32 oversize_received;
        u32 jabber_received;
        u32 mac_receive_error;
        u32 bad_crc_event;
        u32 collision;
        u32 late_collision;
        /* Non MIB hardware counters */
        u32 rx_discard;
        u32 rx_overrun;
};

struct rx_queue {
        int index;

        int rx_ring_size;

        int rx_desc_count;
        int rx_curr_desc;
        int rx_used_desc;

        struct rx_desc *rx_desc_area;
        dma_addr_t rx_desc_dma;
        int rx_desc_area_size;
        struct sk_buff **rx_skb;
};

struct tx_queue {
        int index;

        int tx_ring_size;

        int tx_desc_count;
        int tx_curr_desc;
        int tx_used_desc;

        int tx_stop_threshold;
        int tx_wake_threshold;

        char *tso_hdrs;
        dma_addr_t tso_hdrs_dma;

        struct tx_desc *tx_desc_area;
        char *tx_desc_mapping; /* array to track the type of the dma mapping */
        dma_addr_t tx_desc_dma;
        int tx_desc_area_size;

        struct sk_buff_head tx_skb;

        unsigned long tx_packets;
        unsigned long tx_bytes;
        unsigned long tx_dropped;
};

struct mv643xx_eth_private {
        struct mv643xx_eth_shared_private *shared;
        void __iomem *base;
        int port_num;

        struct net_device *dev;

        struct phy_device *phy;

        struct timer_list mib_counters_timer;
        spinlock_t mib_counters_lock;
        struct mib_counters mib_counters;

        struct work_struct tx_timeout_task;

        struct napi_struct napi;
        u32 int_mask;
        u8 oom;
        u8 work_link;
        u8 work_tx;
        u8 work_tx_end;
        u8 work_rx;
        u8 work_rx_refill;

        int skb_size;

        /*
         * RX state.
         */
        int rx_ring_size;
        unsigned long rx_desc_sram_addr;
        int rx_desc_sram_size;
        int rxq_count;
        struct timer_list rx_oom;
        struct rx_queue rxq[8];

        /*
         * TX state.
         */
        int tx_ring_size;
        unsigned long tx_desc_sram_addr;
        int tx_desc_sram_size;
        int txq_count;
        struct tx_queue txq[8];

        /*
         * Hardware-specific parameters.
         */
        struct clk *clk;
        unsigned int t_clk;
};


/* port register accessors **************************************************/
static inline u32 rdl(struct mv643xx_eth_private *mp, int offset)
{
        return readl(mp->shared->base + offset);
}

static inline u32 rdlp(struct mv643xx_eth_private *mp, int offset)
{
        return readl(mp->base + offset);
}

static inline void wrl(struct mv643xx_eth_private *mp, int offset, u32 data)
{
        writel(data, mp->shared->base + offset);
}

static inline void wrlp(struct mv643xx_eth_private *mp, int offset, u32 data)
{
        writel(data, mp->base + offset);
}


/* rxq/txq helper functions *************************************************/
static struct mv643xx_eth_private *rxq_to_mp(struct rx_queue *rxq)
{
        return container_of(rxq, struct mv643xx_eth_private, rxq[rxq->index]);
}

static struct mv643xx_eth_private *txq_to_mp(struct tx_queue *txq)
{
        return container_of(txq, struct mv643xx_eth_private, txq[txq->index]);
}

static void rxq_enable(struct rx_queue *rxq)
{
        struct mv643xx_eth_private *mp = rxq_to_mp(rxq);
        wrlp(mp, RXQ_COMMAND, 1 << rxq->index);
}

static void rxq_disable(struct rx_queue *rxq)
{
        struct mv643xx_eth_private *mp = rxq_to_mp(rxq);
        u8 mask = 1 << rxq->index;

        wrlp(mp, RXQ_COMMAND, mask << 8);
        while (rdlp(mp, RXQ_COMMAND) & mask)
                udelay(10);
}

static void txq_reset_hw_ptr(struct tx_queue *txq)
{
        struct mv643xx_eth_private *mp = txq_to_mp(txq);
        u32 addr;

        addr = (u32)txq->tx_desc_dma;
        addr += txq->tx_curr_desc * sizeof(struct tx_desc);
        wrlp(mp, TXQ_CURRENT_DESC_PTR(txq->index), addr);
}

static void txq_enable(struct tx_queue *txq)
{
        struct mv643xx_eth_private *mp = txq_to_mp(txq);
        wrlp(mp, TXQ_COMMAND, 1 << txq->index);
}

static void txq_disable(struct tx_queue *txq)
{
        struct mv643xx_eth_private *mp = txq_to_mp(txq);
        u8 mask = 1 << txq->index;

        wrlp(mp, TXQ_COMMAND, mask << 8);
        while (rdlp(mp, TXQ_COMMAND) & mask)
                udelay(10);
}

static void txq_maybe_wake(struct tx_queue *txq)
{
        struct mv643xx_eth_private *mp = txq_to_mp(txq);
        struct netdev_queue *nq = netdev_get_tx_queue(mp->dev, txq->index);

        if (netif_tx_queue_stopped(nq)) {
                __netif_tx_lock(nq, smp_processor_id());
                if (txq->tx_desc_count <= txq->tx_wake_threshold)
                        netif_tx_wake_queue(nq);
                __netif_tx_unlock(nq);
        }
}

static int rxq_process(struct rx_queue *rxq, int budget)
{
        struct mv643xx_eth_private *mp = rxq_to_mp(rxq);
        struct net_device_stats *stats = &mp->dev->stats;
        int rx;

        rx = 0;
        while (rx < budget && rxq->rx_desc_count) {
                struct rx_desc *rx_desc;
                unsigned int cmd_sts;
                struct sk_buff *skb;
                u16 byte_cnt;

                rx_desc = &rxq->rx_desc_area[rxq->rx_curr_desc];

                cmd_sts = rx_desc->cmd_sts;
                if (cmd_sts & BUFFER_OWNED_BY_DMA)
                        break;
                rmb();

                skb = rxq->rx_skb[rxq->rx_curr_desc];
                rxq->rx_skb[rxq->rx_curr_desc] = NULL;

                rxq->rx_curr_desc++;
                if (rxq->rx_curr_desc == rxq->rx_ring_size)
                        rxq->rx_curr_desc = 0;

                dma_unmap_single(mp->dev->dev.parent, rx_desc->buf_ptr,
                                 rx_desc->buf_size, DMA_FROM_DEVICE);
                rxq->rx_desc_count--;
                rx++;

                mp->work_rx_refill |= 1 << rxq->index;

                byte_cnt = rx_desc->byte_cnt;

                /*
                 * Update statistics.
                 *
                 * Note that the descriptor byte count includes 2 dummy
                 * bytes automatically inserted by the hardware at the
                 * start of the packet (which we don't count), and a 4
                 * byte CRC at the end of the packet (which we do count).
                 */
                stats->rx_packets++;
                stats->rx_bytes += byte_cnt - 2;

                /*
                 * In case we received a packet without first / last bits
                 * on, or the error summary bit is set, the packet needs
                 * to be dropped.
                 */
                if ((cmd_sts & (RX_FIRST_DESC | RX_LAST_DESC | ERROR_SUMMARY))
                        != (RX_FIRST_DESC | RX_LAST_DESC))
                        goto err;

                /*
                 * The -4 is for the CRC in the trailer of the
                 * received packet
                 */
                skb_put(skb, byte_cnt - 2 - 4);

                if (cmd_sts & LAYER_4_CHECKSUM_OK)
                        skb->ip_summed = CHECKSUM_UNNECESSARY;
                skb->protocol = eth_type_trans(skb, mp->dev);

                napi_gro_receive(&mp->napi, skb);

                continue;

err:
                stats->rx_dropped++;

                if ((cmd_sts & (RX_FIRST_DESC | RX_LAST_DESC)) !=
                        (RX_FIRST_DESC | RX_LAST_DESC)) {
                        if (net_ratelimit())
                                netdev_err(mp->dev,
                                           "received packet spanning multiple descriptors\n");
                }

                if (cmd_sts & ERROR_SUMMARY)
                        stats->rx_errors++;

                dev_kfree_skb(skb);
        }

        if (rx < budget)
                mp->work_rx &= ~(1 << rxq->index);

        return rx;
}

static int rxq_refill(struct rx_queue *rxq, int budget)
{
        struct mv643xx_eth_private *mp = rxq_to_mp(rxq);
        int refilled;

        refilled = 0;
        while (refilled < budget && rxq->rx_desc_count < rxq->rx_ring_size) {
                struct sk_buff *skb;
                int rx;
                struct rx_desc *rx_desc;
                int size;

                skb = netdev_alloc_skb(mp->dev, mp->skb_size);

                if (skb == NULL) {
                        mp->oom = 1;
                        goto oom;
                }

                if (SKB_DMA_REALIGN)
                        skb_reserve(skb, SKB_DMA_REALIGN);

                refilled++;
                rxq->rx_desc_count++;

                rx = rxq->rx_used_desc++;
                if (rxq->rx_used_desc == rxq->rx_ring_size)
                        rxq->rx_used_desc = 0;

                rx_desc = rxq->rx_desc_area + rx;

                size = skb_end_pointer(skb) - skb->data;
                rx_desc->buf_ptr = dma_map_single(mp->dev->dev.parent,
                                                  skb->data, size,
                                                  DMA_FROM_DEVICE);
                rx_desc->buf_size = size;
                rxq->rx_skb[rx] = skb;
                wmb();
                rx_desc->cmd_sts = BUFFER_OWNED_BY_DMA | RX_ENABLE_INTERRUPT;
                wmb();

                /*
                 * The hardware automatically prepends 2 bytes of
                 * dummy data to each received packet, so that the
                 * IP header ends up 16-byte aligned.
                 */
                skb_reserve(skb, 2);
        }

        if (refilled < budget)
                mp->work_rx_refill &= ~(1 << rxq->index);

oom:
        return refilled;
}


/* tx ***********************************************************************/
static inline unsigned int has_tiny_unaligned_frags(struct sk_buff *skb)
{
        int frag;

        for (frag = 0; frag < skb_shinfo(skb)->nr_frags; frag++) {
                const skb_frag_t *fragp = &skb_shinfo(skb)->frags[frag];

                if (skb_frag_size(fragp) <= 8 && fragp->page_offset & 7)
                        return 1;
        }

        return 0;
}

static inline __be16 sum16_as_be(__sum16 sum)
{
        return (__force __be16)sum;
}

static int skb_tx_csum(struct mv643xx_eth_private *mp, struct sk_buff *skb,
                       u16 *l4i_chk, u32 *command, int length)
{
        int ret;
        u32 cmd = 0;

        if (skb->ip_summed == CHECKSUM_PARTIAL) {
                int hdr_len;
                int tag_bytes;

                BUG_ON(skb->protocol != htons(ETH_P_IP) &&
                       skb->protocol != htons(ETH_P_8021Q));

                hdr_len = (void *)ip_hdr(skb) - (void *)skb->data;
                tag_bytes = hdr_len - ETH_HLEN;

                if (length - hdr_len > mp->shared->tx_csum_limit ||
                    unlikely(tag_bytes & ~12)) {
                        ret = skb_checksum_help(skb);
                        if (!ret)
                                goto no_csum;
                        return ret;
                }

                if (tag_bytes & 4)
                        cmd |= MAC_HDR_EXTRA_4_BYTES;
                if (tag_bytes & 8)
                        cmd |= MAC_HDR_EXTRA_8_BYTES;

                cmd |= GEN_TCP_UDP_CHECKSUM | GEN_TCP_UDP_CHK_FULL |
                           GEN_IP_V4_CHECKSUM   |
                           ip_hdr(skb)->ihl << TX_IHL_SHIFT;

                /* TODO: Revisit this. With the usage of GEN_TCP_UDP_CHK_FULL
                 * it seems we don't need to pass the initial checksum. */
                switch (ip_hdr(skb)->protocol) {
                case IPPROTO_UDP:
                        cmd |= UDP_FRAME;
                        *l4i_chk = 0;
                        break;
                case IPPROTO_TCP:
                        *l4i_chk = 0;
                        break;
                default:
                        WARN(1, "protocol not supported");
                }
        } else {
no_csum:
                /* Errata BTS #50, IHL must be 5 if no HW checksum */
                cmd |= 5 << TX_IHL_SHIFT;
        }
        *command = cmd;
        return 0;
}

static inline int
txq_put_data_tso(struct net_device *dev, struct tx_queue *txq,
                 struct sk_buff *skb, char *data, int length,
                 bool last_tcp, bool is_last)
{
        int tx_index;
        u32 cmd_sts;
        struct tx_desc *desc;

        tx_index = txq->tx_curr_desc++;
        if (txq->tx_curr_desc == txq->tx_ring_size)
                txq->tx_curr_desc = 0;
        desc = &txq->tx_desc_area[tx_index];
        txq->tx_desc_mapping[tx_index] = DESC_DMA_MAP_SINGLE;

        desc->l4i_chk = 0;
        desc->byte_cnt = length;

        if (length <= 8 && (uintptr_t)data & 0x7) {
                /* Copy unaligned small data fragment to TSO header data area */
                memcpy(txq->tso_hdrs + tx_index * TSO_HEADER_SIZE,
                       data, length);
                desc->buf_ptr = txq->tso_hdrs_dma
                        + tx_index * TSO_HEADER_SIZE;
        } else {
                /* Alignment is okay, map buffer and hand off to hardware */
                txq->tx_desc_mapping[tx_index] = DESC_DMA_MAP_SINGLE;
                desc->buf_ptr = dma_map_single(dev->dev.parent, data,
                        length, DMA_TO_DEVICE);
                if (unlikely(dma_mapping_error(dev->dev.parent,
                                               desc->buf_ptr))) {
                        WARN(1, "dma_map_single failed!\n");
                        return -ENOMEM;
                }
        }

        cmd_sts = BUFFER_OWNED_BY_DMA;
        if (last_tcp) {
                /* last descriptor in the TCP packet */
                cmd_sts |= ZERO_PADDING | TX_LAST_DESC;
                /* last descriptor in SKB */
                if (is_last)
                        cmd_sts |= TX_ENABLE_INTERRUPT;
        }
        desc->cmd_sts = cmd_sts;
        return 0;
}

static inline void
txq_put_hdr_tso(struct sk_buff *skb, struct tx_queue *txq, int length,
                u32 *first_cmd_sts, bool first_desc)
{
        struct mv643xx_eth_private *mp = txq_to_mp(txq);
        int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
        int tx_index;
        struct tx_desc *desc;
        int ret;
        u32 cmd_csum = 0;
        u16 l4i_chk = 0;
        u32 cmd_sts;

        tx_index = txq->tx_curr_desc;
        desc = &txq->tx_desc_area[tx_index];

        ret = skb_tx_csum(mp, skb, &l4i_chk, &cmd_csum, length);
        if (ret)
                WARN(1, "failed to prepare checksum!");

        /* Should we set this? Can't use the value from skb_tx_csum()
         * as it's not the correct initial L4 checksum to use. */
        desc->l4i_chk = 0;

        desc->byte_cnt = hdr_len;
        desc->buf_ptr = txq->tso_hdrs_dma +
                        txq->tx_curr_desc * TSO_HEADER_SIZE;
        cmd_sts = cmd_csum | BUFFER_OWNED_BY_DMA  | TX_FIRST_DESC |
                                   GEN_CRC;

        /* Defer updating the first command descriptor until all
         * following descriptors have been written.
         */
        if (first_desc)
                *first_cmd_sts = cmd_sts;
        else
                desc->cmd_sts = cmd_sts;

        txq->tx_curr_desc++;
        if (txq->tx_curr_desc == txq->tx_ring_size)
                txq->tx_curr_desc = 0;
}

static int txq_submit_tso(struct tx_queue *txq, struct sk_buff *skb,
                          struct net_device *dev)
{
        struct mv643xx_eth_private *mp = txq_to_mp(txq);
        int total_len, data_left, ret;
        int desc_count = 0;
        struct tso_t tso;
        int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
        struct tx_desc *first_tx_desc;
        u32 first_cmd_sts = 0;

        /* Count needed descriptors */
        if ((txq->tx_desc_count + tso_count_descs(skb)) >= txq->tx_ring_size) {
                netdev_dbg(dev, "not enough descriptors for TSO!\n");
                return -EBUSY;
        }

        first_tx_desc = &txq->tx_desc_area[txq->tx_curr_desc];

        /* Initialize the TSO handler, and prepare the first payload */
        tso_start(skb, &tso);

        total_len = skb->len - hdr_len;
        while (total_len > 0) {
                bool first_desc = (desc_count == 0);
                char *hdr;

                data_left = min_t(int, skb_shinfo(skb)->gso_size, total_len);
                total_len -= data_left;
                desc_count++;

                /* prepare packet headers: MAC + IP + TCP */
                hdr = txq->tso_hdrs + txq->tx_curr_desc * TSO_HEADER_SIZE;
                tso_build_hdr(skb, hdr, &tso, data_left, total_len == 0);
                txq_put_hdr_tso(skb, txq, data_left, &first_cmd_sts,
                                first_desc);

                while (data_left > 0) {
                        int size;
                        desc_count++;

                        size = min_t(int, tso.size, data_left);
                        ret = txq_put_data_tso(dev, txq, skb, tso.data, size,
                                               size == data_left,
                                               total_len == 0);
                        if (ret)
                                goto err_release;
                        data_left -= size;
                        tso_build_data(skb, &tso, size);
                }
        }

        __skb_queue_tail(&txq->tx_skb, skb);
        skb_tx_timestamp(skb);

        /* ensure all other descriptors are written before first cmd_sts */
        wmb();
        first_tx_desc->cmd_sts = first_cmd_sts;

        /* clear TX_END status */
        mp->work_tx_end &= ~(1 << txq->index);

        /* ensure all descriptors are written before poking hardware */
        wmb();
        txq_enable(txq);
        txq->tx_desc_count += desc_count;
        return 0;
err_release:
        /* TODO: Release all used data descriptors; header descriptors must not
         * be DMA-unmapped.
         */
        return ret;
}

static void txq_submit_frag_skb(struct tx_queue *txq, struct sk_buff *skb)
{
        struct mv643xx_eth_private *mp = txq_to_mp(txq);
        int nr_frags = skb_shinfo(skb)->nr_frags;
        int frag;

        for (frag = 0; frag < nr_frags; frag++) {
                skb_frag_t *this_frag;
                int tx_index;
                struct tx_desc *desc;

                this_frag = &skb_shinfo(skb)->frags[frag];
                tx_index = txq->tx_curr_desc++;
                if (txq->tx_curr_desc == txq->tx_ring_size)
                        txq->tx_curr_desc = 0;
                desc = &txq->tx_desc_area[tx_index];
                txq->tx_desc_mapping[tx_index] = DESC_DMA_MAP_PAGE;

                /*
                 * The last fragment will generate an interrupt
                 * which will free the skb on TX completion.
                 */
                if (frag == nr_frags - 1) {
                        desc->cmd_sts = BUFFER_OWNED_BY_DMA |
                                        ZERO_PADDING | TX_LAST_DESC |
                                        TX_ENABLE_INTERRUPT;
                } else {
                        desc->cmd_sts = BUFFER_OWNED_BY_DMA;
                }

                desc->l4i_chk = 0;
                desc->byte_cnt = skb_frag_size(this_frag);
                desc->buf_ptr = skb_frag_dma_map(mp->dev->dev.parent,
                                                 this_frag, 0, desc->byte_cnt,
                                                 DMA_TO_DEVICE);
        }
}

static int txq_submit_skb(struct tx_queue *txq, struct sk_buff *skb,
                          struct net_device *dev)
{
        struct mv643xx_eth_private *mp = txq_to_mp(txq);
        int nr_frags = skb_shinfo(skb)->nr_frags;
        int tx_index;
        struct tx_desc *desc;
        u32 cmd_sts;
        u16 l4i_chk;
        int length, ret;

        cmd_sts = 0;
        l4i_chk = 0;

        if (txq->tx_ring_size - txq->tx_desc_count < MAX_SKB_FRAGS + 1) {
                if (net_ratelimit())
                        netdev_err(dev, "tx queue full?!\n");
                return -EBUSY;
        }

        ret = skb_tx_csum(mp, skb, &l4i_chk, &cmd_sts, skb->len);
        if (ret)
                return ret;
        cmd_sts |= TX_FIRST_DESC | GEN_CRC | BUFFER_OWNED_BY_DMA;

        tx_index = txq->tx_curr_desc++;
        if (txq->tx_curr_desc == txq->tx_ring_size)
                txq->tx_curr_desc = 0;
        desc = &txq->tx_desc_area[tx_index];
        txq->tx_desc_mapping[tx_index] = DESC_DMA_MAP_SINGLE;

        if (nr_frags) {
                txq_submit_frag_skb(txq, skb);
                length = skb_headlen(skb);
        } else {
                cmd_sts |= ZERO_PADDING | TX_LAST_DESC | TX_ENABLE_INTERRUPT;
                length = skb->len;
        }

        desc->l4i_chk = l4i_chk;
        desc->byte_cnt = length;
        desc->buf_ptr = dma_map_single(mp->dev->dev.parent, skb->data,
                                       length, DMA_TO_DEVICE);

        __skb_queue_tail(&txq->tx_skb, skb);

        skb_tx_timestamp(skb);

        /* ensure all other descriptors are written before first cmd_sts */
        wmb();
        desc->cmd_sts = cmd_sts;

        /* clear TX_END status */

        mp->work_tx_end &= ~(1 << txq->index);

        /* ensure all descriptors are written before poking hardware */
        wmb();
        txq_enable(txq);

        txq->tx_desc_count += nr_frags + 1;

        return 0;
}

static netdev_tx_t mv643xx_eth_xmit(struct sk_buff *skb, struct net_device *dev)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);
        int length, queue, ret;
        struct tx_queue *txq;
        struct netdev_queue *nq;

        queue = skb_get_queue_mapping(skb);
        txq = mp->txq + queue;
        nq = netdev_get_tx_queue(dev, queue);

        if (has_tiny_unaligned_frags(skb) && __skb_linearize(skb)) {
                netdev_printk(KERN_DEBUG, dev,
                              "failed to linearize skb with tiny unaligned fragment\n");
                return NETDEV_TX_BUSY;
        }

        length = skb->len;

        if (skb_is_gso(skb))
                ret = txq_submit_tso(txq, skb, dev);
        else
                ret = txq_submit_skb(txq, skb, dev);
        if (!ret) {
                txq->tx_bytes += length;
                txq->tx_packets++;

                if (txq->tx_desc_count >= txq->tx_stop_threshold)
                        netif_tx_stop_queue(nq);
        } else {
                txq->tx_dropped++;
                dev_kfree_skb_any(skb);
        }

        return NETDEV_TX_OK;
}


/* tx napi ******************************************************************/
static void txq_kick(struct tx_queue *txq)
{
        struct mv643xx_eth_private *mp = txq_to_mp(txq);
        struct netdev_queue *nq = netdev_get_tx_queue(mp->dev, txq->index);
        u32 hw_desc_ptr;
        u32 expected_ptr;

        __netif_tx_lock(nq, smp_processor_id());

        if (rdlp(mp, TXQ_COMMAND) & (1 << txq->index))
                goto out;

        hw_desc_ptr = rdlp(mp, TXQ_CURRENT_DESC_PTR(txq->index));
        expected_ptr = (u32)txq->tx_desc_dma +
                                txq->tx_curr_desc * sizeof(struct tx_desc);

        if (hw_desc_ptr != expected_ptr)
                txq_enable(txq);

out:
        __netif_tx_unlock(nq);

        mp->work_tx_end &= ~(1 << txq->index);
}

static int txq_reclaim(struct tx_queue *txq, int budget, int force)
{
        struct mv643xx_eth_private *mp = txq_to_mp(txq);
        struct netdev_queue *nq = netdev_get_tx_queue(mp->dev, txq->index);
        int reclaimed;

        __netif_tx_lock_bh(nq);

        reclaimed = 0;
        while (reclaimed < budget && txq->tx_desc_count > 0) {
                int tx_index;
                struct tx_desc *desc;
                u32 cmd_sts;
                char desc_dma_map;

                tx_index = txq->tx_used_desc;
                desc = &txq->tx_desc_area[tx_index];
                desc_dma_map = txq->tx_desc_mapping[tx_index];

                cmd_sts = desc->cmd_sts;

                if (cmd_sts & BUFFER_OWNED_BY_DMA) {
                        if (!force)
                                break;
                        desc->cmd_sts = cmd_sts & ~BUFFER_OWNED_BY_DMA;
                }

                txq->tx_used_desc = tx_index + 1;
                if (txq->tx_used_desc == txq->tx_ring_size)
                        txq->tx_used_desc = 0;

                reclaimed++;
                txq->tx_desc_count--;

                if (!IS_TSO_HEADER(txq, desc->buf_ptr)) {

                        if (desc_dma_map == DESC_DMA_MAP_PAGE)
                                dma_unmap_page(mp->dev->dev.parent,
                                               desc->buf_ptr,
                                               desc->byte_cnt,
                                               DMA_TO_DEVICE);
                        else
                                dma_unmap_single(mp->dev->dev.parent,
                                                 desc->buf_ptr,
                                                 desc->byte_cnt,
                                                 DMA_TO_DEVICE);
                }

                if (cmd_sts & TX_ENABLE_INTERRUPT) {
                        struct sk_buff *skb = __skb_dequeue(&txq->tx_skb);

                        if (!WARN_ON(!skb))
                                dev_kfree_skb(skb);
                }

                if (cmd_sts & ERROR_SUMMARY) {
                        netdev_info(mp->dev, "tx error\n");
                        mp->dev->stats.tx_errors++;
                }

        }

        __netif_tx_unlock_bh(nq);

        if (reclaimed < budget)
                mp->work_tx &= ~(1 << txq->index);

        return reclaimed;
}


/* tx rate control **********************************************************/
/*
 * Set total maximum TX rate (shared by all TX queues for this port)
 * to 'rate' bits per second, with a maximum burst of 'burst' bytes.
 */
static void tx_set_rate(struct mv643xx_eth_private *mp, int rate, int burst)
{
        int token_rate;
        int mtu;
        int bucket_size;

        token_rate = ((rate / 1000) * 64) / (mp->t_clk / 1000);
        if (token_rate > 1023)
                token_rate = 1023;

        mtu = (mp->dev->mtu + 255) >> 8;
        if (mtu > 63)
                mtu = 63;

        bucket_size = (burst + 255) >> 8;
        if (bucket_size > 65535)
                bucket_size = 65535;

        switch (mp->shared->tx_bw_control) {
        case TX_BW_CONTROL_OLD_LAYOUT:
                wrlp(mp, TX_BW_RATE, token_rate);
                wrlp(mp, TX_BW_MTU, mtu);
                wrlp(mp, TX_BW_BURST, bucket_size);
                break;
        case TX_BW_CONTROL_NEW_LAYOUT:
                wrlp(mp, TX_BW_RATE_MOVED, token_rate);
                wrlp(mp, TX_BW_MTU_MOVED, mtu);
                wrlp(mp, TX_BW_BURST_MOVED, bucket_size);
                break;
        }
}

static void txq_set_rate(struct tx_queue *txq, int rate, int burst)
{
        struct mv643xx_eth_private *mp = txq_to_mp(txq);
        int token_rate;
        int bucket_size;

        token_rate = ((rate / 1000) * 64) / (mp->t_clk / 1000);
        if (token_rate > 1023)
                token_rate = 1023;

        bucket_size = (burst + 255) >> 8;
        if (bucket_size > 65535)
                bucket_size = 65535;

        wrlp(mp, TXQ_BW_TOKENS(txq->index), token_rate << 14);
        wrlp(mp, TXQ_BW_CONF(txq->index), (bucket_size << 10) | token_rate);
}

static void txq_set_fixed_prio_mode(struct tx_queue *txq)
{
        struct mv643xx_eth_private *mp = txq_to_mp(txq);
        int off;
        u32 val;

        /*
         * Turn on fixed priority mode.
         */
        off = 0;
        switch (mp->shared->tx_bw_control) {
        case TX_BW_CONTROL_OLD_LAYOUT:
                off = TXQ_FIX_PRIO_CONF;
                break;
        case TX_BW_CONTROL_NEW_LAYOUT:
                off = TXQ_FIX_PRIO_CONF_MOVED;
                break;
        }

        if (off) {
                val = rdlp(mp, off);
                val |= 1 << txq->index;
                wrlp(mp, off, val);
        }
}


/* mii management interface *************************************************/
static void mv643xx_eth_adjust_link(struct net_device *dev)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);
        u32 pscr = rdlp(mp, PORT_SERIAL_CONTROL);
        u32 autoneg_disable = FORCE_LINK_PASS |
                     DISABLE_AUTO_NEG_SPEED_GMII |
                     DISABLE_AUTO_NEG_FOR_FLOW_CTRL |
                     DISABLE_AUTO_NEG_FOR_DUPLEX;

        if (mp->phy->autoneg == AUTONEG_ENABLE) {
                /* enable auto negotiation */
                pscr &= ~autoneg_disable;
                goto out_write;
        }

        pscr |= autoneg_disable;

        if (mp->phy->speed == SPEED_1000) {
                /* force gigabit, half duplex not supported */
                pscr |= SET_GMII_SPEED_TO_1000;
                pscr |= SET_FULL_DUPLEX_MODE;
                goto out_write;
        }

        pscr &= ~SET_GMII_SPEED_TO_1000;

        if (mp->phy->speed == SPEED_100)
                pscr |= SET_MII_SPEED_TO_100;
        else
                pscr &= ~SET_MII_SPEED_TO_100;

        if (mp->phy->duplex == DUPLEX_FULL)
                pscr |= SET_FULL_DUPLEX_MODE;
        else
                pscr &= ~SET_FULL_DUPLEX_MODE;

out_write:
        wrlp(mp, PORT_SERIAL_CONTROL, pscr);
}

/* statistics ***************************************************************/
static struct net_device_stats *mv643xx_eth_get_stats(struct net_device *dev)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);
        struct net_device_stats *stats = &dev->stats;
        unsigned long tx_packets = 0;
        unsigned long tx_bytes = 0;
        unsigned long tx_dropped = 0;
        int i;

        for (i = 0; i < mp->txq_count; i++) {
                struct tx_queue *txq = mp->txq + i;

                tx_packets += txq->tx_packets;
                tx_bytes += txq->tx_bytes;
                tx_dropped += txq->tx_dropped;
        }

        stats->tx_packets = tx_packets;
        stats->tx_bytes = tx_bytes;
        stats->tx_dropped = tx_dropped;

        return stats;
}

static inline u32 mib_read(struct mv643xx_eth_private *mp, int offset)
{
        return rdl(mp, MIB_COUNTERS(mp->port_num) + offset);
}

static void mib_counters_clear(struct mv643xx_eth_private *mp)
{
        int i;

        for (i = 0; i < 0x80; i += 4)
                mib_read(mp, i);

        /* Clear non MIB hw counters also */
        rdlp(mp, RX_DISCARD_FRAME_CNT);
        rdlp(mp, RX_OVERRUN_FRAME_CNT);
}

static void mib_counters_update(struct mv643xx_eth_private *mp)
{
        struct mib_counters *p = &mp->mib_counters;

        spin_lock_bh(&mp->mib_counters_lock);
        p->good_octets_received += mib_read(mp, 0x00);
        p->bad_octets_received += mib_read(mp, 0x08);
        p->internal_mac_transmit_err += mib_read(mp, 0x0c);
        p->good_frames_received += mib_read(mp, 0x10);
        p->bad_frames_received += mib_read(mp, 0x14);
        p->broadcast_frames_received += mib_read(mp, 0x18);
        p->multicast_frames_received += mib_read(mp, 0x1c);
        p->frames_64_octets += mib_read(mp, 0x20);
        p->frames_65_to_127_octets += mib_read(mp, 0x24);
        p->frames_128_to_255_octets += mib_read(mp, 0x28);
        p->frames_256_to_511_octets += mib_read(mp, 0x2c);
        p->frames_512_to_1023_octets += mib_read(mp, 0x30);
        p->frames_1024_to_max_octets += mib_read(mp, 0x34);
        p->good_octets_sent += mib_read(mp, 0x38);
        p->good_frames_sent += mib_read(mp, 0x40);
        p->excessive_collision += mib_read(mp, 0x44);
        p->multicast_frames_sent += mib_read(mp, 0x48);
        p->broadcast_frames_sent += mib_read(mp, 0x4c);
        p->unrec_mac_control_received += mib_read(mp, 0x50);
        p->fc_sent += mib_read(mp, 0x54);
        p->good_fc_received += mib_read(mp, 0x58);
        p->bad_fc_received += mib_read(mp, 0x5c);
        p->undersize_received += mib_read(mp, 0x60);
        p->fragments_received += mib_read(mp, 0x64);
        p->oversize_received += mib_read(mp, 0x68);
        p->jabber_received += mib_read(mp, 0x6c);
        p->mac_receive_error += mib_read(mp, 0x70);
        p->bad_crc_event += mib_read(mp, 0x74);
        p->collision += mib_read(mp, 0x78);
        p->late_collision += mib_read(mp, 0x7c);
        /* Non MIB hardware counters */
        p->rx_discard += rdlp(mp, RX_DISCARD_FRAME_CNT);
        p->rx_overrun += rdlp(mp, RX_OVERRUN_FRAME_CNT);
        spin_unlock_bh(&mp->mib_counters_lock);
}

static void mib_counters_timer_wrapper(unsigned long _mp)
{
        struct mv643xx_eth_private *mp = (void *)_mp;
        mib_counters_update(mp);
        mod_timer(&mp->mib_counters_timer, jiffies + 30 * HZ);
}


/* interrupt coalescing *****************************************************/
/*
 * Hardware coalescing parameters are set in units of 64 t_clk
 * cycles.  I.e.:
 *
 *      coal_delay_in_usec = 64000000 * register_value / t_clk_rate
 *
 *      register_value = coal_delay_in_usec * t_clk_rate / 64000000
 *
 * In the ->set*() methods, we round the computed register value
 * to the nearest integer.
 */
static unsigned int get_rx_coal(struct mv643xx_eth_private *mp)
{
        u32 val = rdlp(mp, SDMA_CONFIG);
        u64 temp;

        if (mp->shared->extended_rx_coal_limit)
                temp = ((val & 0x02000000) >> 10) | ((val & 0x003fff80) >> 7);
        else
                temp = (val & 0x003fff00) >> 8;

        temp *= 64000000;
        temp += mp->t_clk / 2;
        do_div(temp, mp->t_clk);

        return (unsigned int)temp;
}

static void set_rx_coal(struct mv643xx_eth_private *mp, unsigned int usec)
{
        u64 temp;
        u32 val;

        temp = (u64)usec * mp->t_clk;
        temp += 31999999;
        do_div(temp, 64000000);

        val = rdlp(mp, SDMA_CONFIG);
        if (mp->shared->extended_rx_coal_limit) {
                if (temp > 0xffff)
                        temp = 0xffff;
                val &= ~0x023fff80;
                val |= (temp & 0x8000) << 10;
                val |= (temp & 0x7fff) << 7;
        } else {
                if (temp > 0x3fff)
                        temp = 0x3fff;
                val &= ~0x003fff00;
                val |= (temp & 0x3fff) << 8;
        }
        wrlp(mp, SDMA_CONFIG, val);
}

static unsigned int get_tx_coal(struct mv643xx_eth_private *mp)
{
        u64 temp;

        temp = (rdlp(mp, TX_FIFO_URGENT_THRESHOLD) & 0x3fff0) >> 4;
        temp *= 64000000;
        temp += mp->t_clk / 2;
        do_div(temp, mp->t_clk);

        return (unsigned int)temp;
}

static void set_tx_coal(struct mv643xx_eth_private *mp, unsigned int usec)
{
        u64 temp;

        temp = (u64)usec * mp->t_clk;
        temp += 31999999;
        do_div(temp, 64000000);

        if (temp > 0x3fff)
                temp = 0x3fff;

        wrlp(mp, TX_FIFO_URGENT_THRESHOLD, temp << 4);
}


/* ethtool ******************************************************************/
struct mv643xx_eth_stats {
        char stat_string[ETH_GSTRING_LEN];
        int sizeof_stat;
        int netdev_off;
        int mp_off;
};

#define SSTAT(m)                                                \
        { #m, FIELD_SIZEOF(struct net_device_stats, m),         \
          offsetof(struct net_device, stats.m), -1 }

#define MIBSTAT(m)                                              \
        { #m, FIELD_SIZEOF(struct mib_counters, m),             \
          -1, offsetof(struct mv643xx_eth_private, mib_counters.m) }

static const struct mv643xx_eth_stats mv643xx_eth_stats[] = {
        SSTAT(rx_packets),
        SSTAT(tx_packets),
        SSTAT(rx_bytes),
        SSTAT(tx_bytes),
        SSTAT(rx_errors),
        SSTAT(tx_errors),
        SSTAT(rx_dropped),
        SSTAT(tx_dropped),
        MIBSTAT(good_octets_received),
        MIBSTAT(bad_octets_received),
        MIBSTAT(internal_mac_transmit_err),
        MIBSTAT(good_frames_received),
        MIBSTAT(bad_frames_received),
        MIBSTAT(broadcast_frames_received),
        MIBSTAT(multicast_frames_received),
        MIBSTAT(frames_64_octets),
        MIBSTAT(frames_65_to_127_octets),
        MIBSTAT(frames_128_to_255_octets),
        MIBSTAT(frames_256_to_511_octets),
        MIBSTAT(frames_512_to_1023_octets),
        MIBSTAT(frames_1024_to_max_octets),
        MIBSTAT(good_octets_sent),
        MIBSTAT(good_frames_sent),
        MIBSTAT(excessive_collision),
        MIBSTAT(multicast_frames_sent),
        MIBSTAT(broadcast_frames_sent),
        MIBSTAT(unrec_mac_control_received),
        MIBSTAT(fc_sent),
        MIBSTAT(good_fc_received),
        MIBSTAT(bad_fc_received),
        MIBSTAT(undersize_received),
        MIBSTAT(fragments_received),
        MIBSTAT(oversize_received),
        MIBSTAT(jabber_received),
        MIBSTAT(mac_receive_error),
        MIBSTAT(bad_crc_event),
        MIBSTAT(collision),
        MIBSTAT(late_collision),
        MIBSTAT(rx_discard),
        MIBSTAT(rx_overrun),
};

static int
mv643xx_eth_get_settings_phy(struct mv643xx_eth_private *mp,
                             struct ethtool_cmd *cmd)
{
        int err;

        err = phy_read_status(mp->phy);
        if (err == 0)
                err = phy_ethtool_gset(mp->phy, cmd);

        /*
         * The MAC does not support 1000baseT_Half.
         */
        cmd->supported &= ~SUPPORTED_1000baseT_Half;
        cmd->advertising &= ~ADVERTISED_1000baseT_Half;

        return err;
}

static int
mv643xx_eth_get_settings_phyless(struct mv643xx_eth_private *mp,
                                 struct ethtool_cmd *cmd)
{
        u32 port_status;

        port_status = rdlp(mp, PORT_STATUS);

        cmd->supported = SUPPORTED_MII;
        cmd->advertising = ADVERTISED_MII;
        switch (port_status & PORT_SPEED_MASK) {
        case PORT_SPEED_10:
                ethtool_cmd_speed_set(cmd, SPEED_10);
                break;
        case PORT_SPEED_100:
                ethtool_cmd_speed_set(cmd, SPEED_100);
                break;
        case PORT_SPEED_1000:
                ethtool_cmd_speed_set(cmd, SPEED_1000);
                break;
        default:
                cmd->speed = -1;
                break;
        }
        cmd->duplex = (port_status & FULL_DUPLEX) ? DUPLEX_FULL : DUPLEX_HALF;
        cmd->port = PORT_MII;
        cmd->phy_address = 0;
        cmd->transceiver = XCVR_INTERNAL;
        cmd->autoneg = AUTONEG_DISABLE;
        cmd->maxtxpkt = 1;
        cmd->maxrxpkt = 1;

        return 0;
}

static void
mv643xx_eth_get_wol(struct net_device *dev, struct ethtool_wolinfo *wol)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);
        wol->supported = 0;
        wol->wolopts = 0;
        if (mp->phy)
                phy_ethtool_get_wol(mp->phy, wol);
}

static int
mv643xx_eth_set_wol(struct net_device *dev, struct ethtool_wolinfo *wol)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);
        int err;

        if (mp->phy == NULL)
                return -EOPNOTSUPP;

        err = phy_ethtool_set_wol(mp->phy, wol);
        /* Given that mv643xx_eth works without the marvell-specific PHY driver,
         * this debugging hint is useful to have.
         */
        if (err == -EOPNOTSUPP)
                netdev_info(dev, "The PHY does not support set_wol, was CONFIG_MARVELL_PHY enabled?\n");
        return err;
}

static int
mv643xx_eth_get_settings(struct net_device *dev, struct ethtool_cmd *cmd)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);

        if (mp->phy != NULL)
                return mv643xx_eth_get_settings_phy(mp, cmd);
        else
                return mv643xx_eth_get_settings_phyless(mp, cmd);
}

static int
mv643xx_eth_set_settings(struct net_device *dev, struct ethtool_cmd *cmd)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);
        int ret;

        if (mp->phy == NULL)
                return -EINVAL;

        /*
         * The MAC does not support 1000baseT_Half.
         */
        cmd->advertising &= ~ADVERTISED_1000baseT_Half;

        ret = phy_ethtool_sset(mp->phy, cmd);
        if (!ret)
                mv643xx_eth_adjust_link(dev);
        return ret;
}

static void mv643xx_eth_get_drvinfo(struct net_device *dev,
                                    struct ethtool_drvinfo *drvinfo)
{
        strlcpy(drvinfo->driver, mv643xx_eth_driver_name,
                sizeof(drvinfo->driver));
        strlcpy(drvinfo->version, mv643xx_eth_driver_version,
                sizeof(drvinfo->version));
        strlcpy(drvinfo->fw_version, "N/A", sizeof(drvinfo->fw_version));
        strlcpy(drvinfo->bus_info, "platform", sizeof(drvinfo->bus_info));
}

static int mv643xx_eth_nway_reset(struct net_device *dev)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);

        if (mp->phy == NULL)
                return -EINVAL;

        return genphy_restart_aneg(mp->phy);
}

static int
mv643xx_eth_get_coalesce(struct net_device *dev, struct ethtool_coalesce *ec)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);

        ec->rx_coalesce_usecs = get_rx_coal(mp);
        ec->tx_coalesce_usecs = get_tx_coal(mp);

        return 0;
}

static int
mv643xx_eth_set_coalesce(struct net_device *dev, struct ethtool_coalesce *ec)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);

        set_rx_coal(mp, ec->rx_coalesce_usecs);
        set_tx_coal(mp, ec->tx_coalesce_usecs);

        return 0;
}

static void
mv643xx_eth_get_ringparam(struct net_device *dev, struct ethtool_ringparam *er)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);

        er->rx_max_pending = 4096;
        er->tx_max_pending = 4096;

        er->rx_pending = mp->rx_ring_size;
        er->tx_pending = mp->tx_ring_size;
}

static int
mv643xx_eth_set_ringparam(struct net_device *dev, struct ethtool_ringparam *er)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);

        if (er->rx_mini_pending || er->rx_jumbo_pending)
                return -EINVAL;

        mp->rx_ring_size = er->rx_pending < 4096 ? er->rx_pending : 4096;
        mp->tx_ring_size = clamp_t(unsigned int, er->tx_pending,
                                   MV643XX_MAX_SKB_DESCS * 2, 4096);
        if (mp->tx_ring_size != er->tx_pending)
                netdev_warn(dev, "TX queue size set to %u (requested %u)\n",
                            mp->tx_ring_size, er->tx_pending);

        if (netif_running(dev)) {
                mv643xx_eth_stop(dev);
                if (mv643xx_eth_open(dev)) {
                        netdev_err(dev,
                                   "fatal error on re-opening device after ring param change\n");
                        return -ENOMEM;
                }
        }

        return 0;
}


static int
mv643xx_eth_set_features(struct net_device *dev, netdev_features_t features)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);
        bool rx_csum = features & NETIF_F_RXCSUM;

        wrlp(mp, PORT_CONFIG, rx_csum ? 0x02000000 : 0x00000000);

        return 0;
}

static void mv643xx_eth_get_strings(struct net_device *dev,
                                    uint32_t stringset, uint8_t *data)
{
        int i;

        if (stringset == ETH_SS_STATS) {
                for (i = 0; i < ARRAY_SIZE(mv643xx_eth_stats); i++) {
                        memcpy(data + i * ETH_GSTRING_LEN,
                                mv643xx_eth_stats[i].stat_string,
                                ETH_GSTRING_LEN);
                }
        }
}

static void mv643xx_eth_get_ethtool_stats(struct net_device *dev,
                                          struct ethtool_stats *stats,
                                          uint64_t *data)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);
        int i;

        mv643xx_eth_get_stats(dev);
        mib_counters_update(mp);

        for (i = 0; i < ARRAY_SIZE(mv643xx_eth_stats); i++) {
                const struct mv643xx_eth_stats *stat;
                void *p;

                stat = mv643xx_eth_stats + i;

                if (stat->netdev_off >= 0)
                        p = ((void *)mp->dev) + stat->netdev_off;
                else
                        p = ((void *)mp) + stat->mp_off;

                data[i] = (stat->sizeof_stat == 8) ?
                                *(uint64_t *)p : *(uint32_t *)p;
        }
}

static int mv643xx_eth_get_sset_count(struct net_device *dev, int sset)
{
        if (sset == ETH_SS_STATS)
                return ARRAY_SIZE(mv643xx_eth_stats);

        return -EOPNOTSUPP;
}

static const struct ethtool_ops mv643xx_eth_ethtool_ops = {
        .get_settings           = mv643xx_eth_get_settings,
        .set_settings           = mv643xx_eth_set_settings,
        .get_drvinfo            = mv643xx_eth_get_drvinfo,
        .nway_reset             = mv643xx_eth_nway_reset,
        .get_link               = ethtool_op_get_link,
        .get_coalesce           = mv643xx_eth_get_coalesce,
        .set_coalesce           = mv643xx_eth_set_coalesce,
        .get_ringparam          = mv643xx_eth_get_ringparam,
        .set_ringparam          = mv643xx_eth_set_ringparam,
        .get_strings            = mv643xx_eth_get_strings,
        .get_ethtool_stats      = mv643xx_eth_get_ethtool_stats,
        .get_sset_count         = mv643xx_eth_get_sset_count,
        .get_ts_info            = ethtool_op_get_ts_info,
        .get_wol                = mv643xx_eth_get_wol,
        .set_wol                = mv643xx_eth_set_wol,
};


/* address handling *********************************************************/
static void uc_addr_get(struct mv643xx_eth_private *mp, unsigned char *addr)
{
        unsigned int mac_h = rdlp(mp, MAC_ADDR_HIGH);
        unsigned int mac_l = rdlp(mp, MAC_ADDR_LOW);

        addr[0] = (mac_h >> 24) & 0xff;
        addr[1] = (mac_h >> 16) & 0xff;
        addr[2] = (mac_h >> 8) & 0xff;
        addr[3] = mac_h & 0xff;
        addr[4] = (mac_l >> 8) & 0xff;
        addr[5] = mac_l & 0xff;
}

static void uc_addr_set(struct mv643xx_eth_private *mp, unsigned char *addr)
{
        wrlp(mp, MAC_ADDR_HIGH,
                (addr[0] << 24) | (addr[1] << 16) | (addr[2] << 8) | addr[3]);
        wrlp(mp, MAC_ADDR_LOW, (addr[4] << 8) | addr[5]);
}

static u32 uc_addr_filter_mask(struct net_device *dev)
{
        struct netdev_hw_addr *ha;
        u32 nibbles;

        if (dev->flags & IFF_PROMISC)
                return 0;

        nibbles = 1 << (dev->dev_addr[5] & 0x0f);
        netdev_for_each_uc_addr(ha, dev) {
                if (memcmp(dev->dev_addr, ha->addr, 5))
                        return 0;
                if ((dev->dev_addr[5] ^ ha->addr[5]) & 0xf0)
                        return 0;

                nibbles |= 1 << (ha->addr[5] & 0x0f);
        }

        return nibbles;
}

static void mv643xx_eth_program_unicast_filter(struct net_device *dev)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);
        u32 port_config;
        u32 nibbles;
        int i;

        uc_addr_set(mp, dev->dev_addr);

        port_config = rdlp(mp, PORT_CONFIG) & ~UNICAST_PROMISCUOUS_MODE;

        nibbles = uc_addr_filter_mask(dev);
        if (!nibbles) {
                port_config |= UNICAST_PROMISCUOUS_MODE;
                nibbles = 0xffff;
        }

        for (i = 0; i < 16; i += 4) {
                int off = UNICAST_TABLE(mp->port_num) + i;
                u32 v;

                v = 0;
                if (nibbles & 1)
                        v |= 0x00000001;
                if (nibbles & 2)
                        v |= 0x00000100;
                if (nibbles & 4)
                        v |= 0x00010000;
                if (nibbles & 8)
                        v |= 0x01000000;
                nibbles >>= 4;

                wrl(mp, off, v);
        }

        wrlp(mp, PORT_CONFIG, port_config);
}

static int addr_crc(unsigned char *addr)
{
        int crc = 0;
        int i;

        for (i = 0; i < 6; i++) {
                int j;

                crc = (crc ^ addr[i]) << 8;
                for (j = 7; j >= 0; j--) {
                        if (crc & (0x100 << j))
                                crc ^= 0x107 << j;
                }
        }

        return crc;
}

static void mv643xx_eth_program_multicast_filter(struct net_device *dev)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);
        u32 *mc_spec;
        u32 *mc_other;
        struct netdev_hw_addr *ha;
        int i;

        if (dev->flags & (IFF_PROMISC | IFF_ALLMULTI))
                goto promiscuous;

        /* Allocate both mc_spec and mc_other tables */
        mc_spec = kcalloc(128, sizeof(u32), GFP_ATOMIC);
        if (!mc_spec)
                goto promiscuous;
        mc_other = &mc_spec[64];

        netdev_for_each_mc_addr(ha, dev) {
                u8 *a = ha->addr;
                u32 *table;
                u8 entry;

                if (memcmp(a, "\x01\x00\x5e\x00\x00", 5) == 0) {
                        table = mc_spec;
                        entry = a[5];
                } else {
                        table = mc_other;
                        entry = addr_crc(a);
                }

                table[entry >> 2] |= 1 << (8 * (entry & 3));
        }

        for (i = 0; i < 64; i++) {
                wrl(mp, SPECIAL_MCAST_TABLE(mp->port_num) + i * sizeof(u32),
                    mc_spec[i]);
                wrl(mp, OTHER_MCAST_TABLE(mp->port_num) + i * sizeof(u32),
                    mc_other[i]);
        }

        kfree(mc_spec);
        return;

promiscuous:
        for (i = 0; i < 64; i++) {
                wrl(mp, SPECIAL_MCAST_TABLE(mp->port_num) + i * sizeof(u32),
                    0x01010101u);
                wrl(mp, OTHER_MCAST_TABLE(mp->port_num) + i * sizeof(u32),
                    0x01010101u);
        }
}

static void mv643xx_eth_set_rx_mode(struct net_device *dev)
{
        mv643xx_eth_program_unicast_filter(dev);
        mv643xx_eth_program_multicast_filter(dev);
}

static int mv643xx_eth_set_mac_address(struct net_device *dev, void *addr)
{
        struct sockaddr *sa = addr;

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

        memcpy(dev->dev_addr, sa->sa_data, ETH_ALEN);

        netif_addr_lock_bh(dev);
        mv643xx_eth_program_unicast_filter(dev);
        netif_addr_unlock_bh(dev);

        return 0;
}


/* rx/tx queue initialisation ***********************************************/
static int rxq_init(struct mv643xx_eth_private *mp, int index)
{
        struct rx_queue *rxq = mp->rxq + index;
        struct rx_desc *rx_desc;
        int size;
        int i;

        rxq->index = index;

        rxq->rx_ring_size = mp->rx_ring_size;

        rxq->rx_desc_count = 0;
        rxq->rx_curr_desc = 0;
        rxq->rx_used_desc = 0;

        size = rxq->rx_ring_size * sizeof(struct rx_desc);

        if (index == 0 && size <= mp->rx_desc_sram_size) {
                rxq->rx_desc_area = ioremap(mp->rx_desc_sram_addr,
                                                mp->rx_desc_sram_size);
                rxq->rx_desc_dma = mp->rx_desc_sram_addr;
        } else {
                rxq->rx_desc_area = dma_alloc_coherent(mp->dev->dev.parent,
                                                       size, &rxq->rx_desc_dma,
                                                       GFP_KERNEL);
        }

        if (rxq->rx_desc_area == NULL) {
                netdev_err(mp->dev,
                           "can't allocate rx ring (%d bytes)\n", size);
                goto out;
        }
        memset(rxq->rx_desc_area, 0, size);

        rxq->rx_desc_area_size = size;
        rxq->rx_skb = kcalloc(rxq->rx_ring_size, sizeof(*rxq->rx_skb),
                                    GFP_KERNEL);
        if (rxq->rx_skb == NULL)
                goto out_free;

        rx_desc = rxq->rx_desc_area;
        for (i = 0; i < rxq->rx_ring_size; i++) {
                int nexti;

                nexti = i + 1;
                if (nexti == rxq->rx_ring_size)
                        nexti = 0;

                rx_desc[i].next_desc_ptr = rxq->rx_desc_dma +
                                        nexti * sizeof(struct rx_desc);
        }

        return 0;


out_free:
        if (index == 0 && size <= mp->rx_desc_sram_size)
                iounmap(rxq->rx_desc_area);
        else
                dma_free_coherent(mp->dev->dev.parent, size,
                                  rxq->rx_desc_area,
                                  rxq->rx_desc_dma);

out:
        return -ENOMEM;
}

static void rxq_deinit(struct rx_queue *rxq)
{
        struct mv643xx_eth_private *mp = rxq_to_mp(rxq);
        int i;

        rxq_disable(rxq);

        for (i = 0; i < rxq->rx_ring_size; i++) {
                if (rxq->rx_skb[i]) {
                        dev_kfree_skb(rxq->rx_skb[i]);
                        rxq->rx_desc_count--;
                }
        }

        if (rxq->rx_desc_count) {
                netdev_err(mp->dev, "error freeing rx ring -- %d skbs stuck\n",
                           rxq->rx_desc_count);
        }

        if (rxq->index == 0 &&
            rxq->rx_desc_area_size <= mp->rx_desc_sram_size)
                iounmap(rxq->rx_desc_area);
        else
                dma_free_coherent(mp->dev->dev.parent, rxq->rx_desc_area_size,
                                  rxq->rx_desc_area, rxq->rx_desc_dma);

        kfree(rxq->rx_skb);
}

static int txq_init(struct mv643xx_eth_private *mp, int index)
{
        struct tx_queue *txq = mp->txq + index;
        struct tx_desc *tx_desc;
        int size;
        int ret;
        int i;

        txq->index = index;

        txq->tx_ring_size = mp->tx_ring_size;

        /* A queue must always have room for at least one skb.
         * Therefore, stop the queue when the free entries reaches
         * the maximum number of descriptors per skb.
         */
        txq->tx_stop_threshold = txq->tx_ring_size - MV643XX_MAX_SKB_DESCS;
        txq->tx_wake_threshold = txq->tx_stop_threshold / 2;

        txq->tx_desc_count = 0;
        txq->tx_curr_desc = 0;
        txq->tx_used_desc = 0;

        size = txq->tx_ring_size * sizeof(struct tx_desc);

        if (index == 0 && size <= mp->tx_desc_sram_size) {
                txq->tx_desc_area = ioremap(mp->tx_desc_sram_addr,
                                                mp->tx_desc_sram_size);
                txq->tx_desc_dma = mp->tx_desc_sram_addr;
        } else {
                txq->tx_desc_area = dma_alloc_coherent(mp->dev->dev.parent,
                                                       size, &txq->tx_desc_dma,
                                                       GFP_KERNEL);
        }

        if (txq->tx_desc_area == NULL) {
                netdev_err(mp->dev,
                           "can't allocate tx ring (%d bytes)\n", size);
                return -ENOMEM;
        }
        memset(txq->tx_desc_area, 0, size);

        txq->tx_desc_area_size = size;

        tx_desc = txq->tx_desc_area;
        for (i = 0; i < txq->tx_ring_size; i++) {
                struct tx_desc *txd = tx_desc + i;
                int nexti;

                nexti = i + 1;
                if (nexti == txq->tx_ring_size)
                        nexti = 0;

                txd->cmd_sts = 0;
                txd->next_desc_ptr = txq->tx_desc_dma +
                                        nexti * sizeof(struct tx_desc);
        }

        txq->tx_desc_mapping = kcalloc(txq->tx_ring_size, sizeof(char),
                                       GFP_KERNEL);
        if (!txq->tx_desc_mapping) {
                ret = -ENOMEM;
                goto err_free_desc_area;
        }

        /* Allocate DMA buffers for TSO MAC/IP/TCP headers */
        txq->tso_hdrs = dma_alloc_coherent(mp->dev->dev.parent,
                                           txq->tx_ring_size * TSO_HEADER_SIZE,
                                           &txq->tso_hdrs_dma, GFP_KERNEL);
        if (txq->tso_hdrs == NULL) {
                ret = -ENOMEM;
                goto err_free_desc_mapping;
        }
        skb_queue_head_init(&txq->tx_skb);

        return 0;

err_free_desc_mapping:
        kfree(txq->tx_desc_mapping);
err_free_desc_area:
        if (index == 0 && size <= mp->tx_desc_sram_size)
                iounmap(txq->tx_desc_area);
        else
                dma_free_coherent(mp->dev->dev.parent, txq->tx_desc_area_size,
                                  txq->tx_desc_area, txq->tx_desc_dma);
        return ret;
}

static void txq_deinit(struct tx_queue *txq)
{
        struct mv643xx_eth_private *mp = txq_to_mp(txq);

        txq_disable(txq);
        txq_reclaim(txq, txq->tx_ring_size, 1);

        BUG_ON(txq->tx_used_desc != txq->tx_curr_desc);

        if (txq->index == 0 &&
            txq->tx_desc_area_size <= mp->tx_desc_sram_size)
                iounmap(txq->tx_desc_area);
        else
                dma_free_coherent(mp->dev->dev.parent, txq->tx_desc_area_size,
                                  txq->tx_desc_area, txq->tx_desc_dma);
        kfree(txq->tx_desc_mapping);

        if (txq->tso_hdrs)
                dma_free_coherent(mp->dev->dev.parent,
                                  txq->tx_ring_size * TSO_HEADER_SIZE,
                                  txq->tso_hdrs, txq->tso_hdrs_dma);
}


/* netdev ops and related ***************************************************/
static int mv643xx_eth_collect_events(struct mv643xx_eth_private *mp)
{
        u32 int_cause;
        u32 int_cause_ext;

        int_cause = rdlp(mp, INT_CAUSE) & mp->int_mask;
        if (int_cause == 0)
                return 0;

        int_cause_ext = 0;
        if (int_cause & INT_EXT) {
                int_cause &= ~INT_EXT;
                int_cause_ext = rdlp(mp, INT_CAUSE_EXT);
        }

        if (int_cause) {
                wrlp(mp, INT_CAUSE, ~int_cause);
                mp->work_tx_end |= ((int_cause & INT_TX_END) >> 19) &
                                ~(rdlp(mp, TXQ_COMMAND) & 0xff);
                mp->work_rx |= (int_cause & INT_RX) >> 2;
        }

        int_cause_ext &= INT_EXT_LINK_PHY | INT_EXT_TX;
        if (int_cause_ext) {
                wrlp(mp, INT_CAUSE_EXT, ~int_cause_ext);
                if (int_cause_ext & INT_EXT_LINK_PHY)
                        mp->work_link = 1;
                mp->work_tx |= int_cause_ext & INT_EXT_TX;
        }

        return 1;
}

static irqreturn_t mv643xx_eth_irq(int irq, void *dev_id)
{
        struct net_device *dev = (struct net_device *)dev_id;
        struct mv643xx_eth_private *mp = netdev_priv(dev);

        if (unlikely(!mv643xx_eth_collect_events(mp)))
                return IRQ_NONE;

        wrlp(mp, INT_MASK, 0);
        napi_schedule(&mp->napi);

        return IRQ_HANDLED;
}

static void handle_link_event(struct mv643xx_eth_private *mp)
{
        struct net_device *dev = mp->dev;
        u32 port_status;
        int speed;
        int duplex;
        int fc;

        port_status = rdlp(mp, PORT_STATUS);
        if (!(port_status & LINK_UP)) {
                if (netif_carrier_ok(dev)) {
                        int i;

                        netdev_info(dev, "link down\n");

                        netif_carrier_off(dev);

                        for (i = 0; i < mp->txq_count; i++) {
                                struct tx_queue *txq = mp->txq + i;

                                txq_reclaim(txq, txq->tx_ring_size, 1);
                                txq_reset_hw_ptr(txq);
                        }
                }
                return;
        }

        switch (port_status & PORT_SPEED_MASK) {
        case PORT_SPEED_10:
                speed = 10;
                break;
        case PORT_SPEED_100:
                speed = 100;
                break;
        case PORT_SPEED_1000:
                speed = 1000;
                break;
        default:
                speed = -1;
                break;
        }
        duplex = (port_status & FULL_DUPLEX) ? 1 : 0;
        fc = (port_status & FLOW_CONTROL_ENABLED) ? 1 : 0;

        netdev_info(dev, "link up, %d Mb/s, %s duplex, flow control %sabled\n",
                    speed, duplex ? "full" : "half", fc ? "en" : "dis");

        if (!netif_carrier_ok(dev))
                netif_carrier_on(dev);
}

static int mv643xx_eth_poll(struct napi_struct *napi, int budget)
{
        struct mv643xx_eth_private *mp;
        int work_done;

        mp = container_of(napi, struct mv643xx_eth_private, napi);

        if (unlikely(mp->oom)) {
                mp->oom = 0;
                del_timer(&mp->rx_oom);
        }

        work_done = 0;
        while (work_done < budget) {
                u8 queue_mask;
                int queue;
                int work_tbd;

                if (mp->work_link) {
                        mp->work_link = 0;
                        handle_link_event(mp);
                        work_done++;
                        continue;
                }

                queue_mask = mp->work_tx | mp->work_tx_end | mp->work_rx;
                if (likely(!mp->oom))
                        queue_mask |= mp->work_rx_refill;

                if (!queue_mask) {
                        if (mv643xx_eth_collect_events(mp))
                                continue;
                        break;
                }

                queue = fls(queue_mask) - 1;
                queue_mask = 1 << queue;

                work_tbd = budget - work_done;
                if (work_tbd > 16)
                        work_tbd = 16;

                if (mp->work_tx_end & queue_mask) {
                        txq_kick(mp->txq + queue);
                } else if (mp->work_tx & queue_mask) {
                        work_done += txq_reclaim(mp->txq + queue, work_tbd, 0);
                        txq_maybe_wake(mp->txq + queue);
                } else if (mp->work_rx & queue_mask) {
                        work_done += rxq_process(mp->rxq + queue, work_tbd);
                } else if (!mp->oom && (mp->work_rx_refill & queue_mask)) {
                        work_done += rxq_refill(mp->rxq + queue, work_tbd);
                } else {
                        BUG();
                }
        }

        if (work_done < budget) {
                if (mp->oom)
                        mod_timer(&mp->rx_oom, jiffies + (HZ / 10));
                napi_complete(napi);
                wrlp(mp, INT_MASK, mp->int_mask);
        }

        return work_done;
}

static inline void oom_timer_wrapper(unsigned long data)
{
        struct mv643xx_eth_private *mp = (void *)data;

        napi_schedule(&mp->napi);
}

static void port_start(struct mv643xx_eth_private *mp)
{
        u32 pscr;
        int i;

        /*
         * Perform PHY reset, if there is a PHY.
         */
        if (mp->phy != NULL) {
                struct ethtool_cmd cmd;

                mv643xx_eth_get_settings(mp->dev, &cmd);
                phy_init_hw(mp->phy);
                mv643xx_eth_set_settings(mp->dev, &cmd);
                phy_start(mp->phy);
        }

        /*
         * Configure basic link parameters.
         */
        pscr = rdlp(mp, PORT_SERIAL_CONTROL);

        pscr |= SERIAL_PORT_ENABLE;
        wrlp(mp, PORT_SERIAL_CONTROL, pscr);

        pscr |= DO_NOT_FORCE_LINK_FAIL;
        if (mp->phy == NULL)
                pscr |= FORCE_LINK_PASS;
        wrlp(mp, PORT_SERIAL_CONTROL, pscr);

        /*
         * Configure TX path and queues.
         */
        tx_set_rate(mp, 1000000000, 16777216);
        for (i = 0; i < mp->txq_count; i++) {
                struct tx_queue *txq = mp->txq + i;

                txq_reset_hw_ptr(txq);
                txq_set_rate(txq, 1000000000, 16777216);
                txq_set_fixed_prio_mode(txq);
        }

        /*
         * Receive all unmatched unicast, TCP, UDP, BPDU and broadcast
         * frames to RX queue #0, and include the pseudo-header when
         * calculating receive checksums.
         */
        mv643xx_eth_set_features(mp->dev, mp->dev->features);

        /*
         * Treat BPDUs as normal multicasts, and disable partition mode.
         */
        wrlp(mp, PORT_CONFIG_EXT, 0x00000000);

        /*
         * Add configured unicast addresses to address filter table.
         */
        mv643xx_eth_program_unicast_filter(mp->dev);

        /*
         * Enable the receive queues.
         */
        for (i = 0; i < mp->rxq_count; i++) {
                struct rx_queue *rxq = mp->rxq + i;
                u32 addr;

                addr = (u32)rxq->rx_desc_dma;
                addr += rxq->rx_curr_desc * sizeof(struct rx_desc);
                wrlp(mp, RXQ_CURRENT_DESC_PTR(i), addr);

                rxq_enable(rxq);
        }
}

static void mv643xx_eth_recalc_skb_size(struct mv643xx_eth_private *mp)
{
        int skb_size;

        /*
         * Reserve 2+14 bytes for an ethernet header (the hardware
         * automatically prepends 2 bytes of dummy data to each
         * received packet), 16 bytes for up to four VLAN tags, and
         * 4 bytes for the trailing FCS -- 36 bytes total.
         */
        skb_size = mp->dev->mtu + 36;

        /*
         * Make sure that the skb size is a multiple of 8 bytes, as
         * the lower three bits of the receive descriptor's buffer
         * size field are ignored by the hardware.
         */
        mp->skb_size = (skb_size + 7) & ~7;

        /*
         * If NET_SKB_PAD is smaller than a cache line,
         * netdev_alloc_skb() will cause skb->data to be misaligned
         * to a cache line boundary.  If this is the case, include
         * some extra space to allow re-aligning the data area.
         */
        mp->skb_size += SKB_DMA_REALIGN;
}

static int mv643xx_eth_open(struct net_device *dev)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);
        int err;
        int i;

        wrlp(mp, INT_CAUSE, 0);
        wrlp(mp, INT_CAUSE_EXT, 0);
        rdlp(mp, INT_CAUSE_EXT);

        err = request_irq(dev->irq, mv643xx_eth_irq,
                          IRQF_SHARED, dev->name, dev);
        if (err) {
                netdev_err(dev, "can't assign irq\n");
                return -EAGAIN;
        }

        mv643xx_eth_recalc_skb_size(mp);

        napi_enable(&mp->napi);

        mp->int_mask = INT_EXT;

        for (i = 0; i < mp->rxq_count; i++) {
                err = rxq_init(mp, i);
                if (err) {
                        while (--i >= 0)
                                rxq_deinit(mp->rxq + i);
                        goto out;
                }

                rxq_refill(mp->rxq + i, INT_MAX);
                mp->int_mask |= INT_RX_0 << i;
        }

        if (mp->oom) {
                mp->rx_oom.expires = jiffies + (HZ / 10);
                add_timer(&mp->rx_oom);
        }

        for (i = 0; i < mp->txq_count; i++) {
                err = txq_init(mp, i);
                if (err) {
                        while (--i >= 0)
                                txq_deinit(mp->txq + i);
                        goto out_free;
                }
                mp->int_mask |= INT_TX_END_0 << i;
        }

        add_timer(&mp->mib_counters_timer);
        port_start(mp);

        wrlp(mp, INT_MASK_EXT, INT_EXT_LINK_PHY | INT_EXT_TX);
        wrlp(mp, INT_MASK, mp->int_mask);

        return 0;


out_free:
        for (i = 0; i < mp->rxq_count; i++)
                rxq_deinit(mp->rxq + i);
out:
        free_irq(dev->irq, dev);

        return err;
}

static void port_reset(struct mv643xx_eth_private *mp)
{
        unsigned int data;
        int i;

        for (i = 0; i < mp->rxq_count; i++)
                rxq_disable(mp->rxq + i);
        for (i = 0; i < mp->txq_count; i++)
                txq_disable(mp->txq + i);

        while (1) {
                u32 ps = rdlp(mp, PORT_STATUS);

                if ((ps & (TX_IN_PROGRESS | TX_FIFO_EMPTY)) == TX_FIFO_EMPTY)
                        break;
                udelay(10);
        }

        /* Reset the Enable bit in the Configuration Register */
        data = rdlp(mp, PORT_SERIAL_CONTROL);
        data &= ~(SERIAL_PORT_ENABLE            |
                  DO_NOT_FORCE_LINK_FAIL        |
                  FORCE_LINK_PASS);
        wrlp(mp, PORT_SERIAL_CONTROL, data);
}

static int mv643xx_eth_stop(struct net_device *dev)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);
        int i;

        wrlp(mp, INT_MASK_EXT, 0x00000000);
        wrlp(mp, INT_MASK, 0x00000000);
        rdlp(mp, INT_MASK);

        napi_disable(&mp->napi);

        del_timer_sync(&mp->rx_oom);

        netif_carrier_off(dev);
        if (mp->phy)
                phy_stop(mp->phy);
        free_irq(dev->irq, dev);

        port_reset(mp);
        mv643xx_eth_get_stats(dev);
        mib_counters_update(mp);
        del_timer_sync(&mp->mib_counters_timer);

        for (i = 0; i < mp->rxq_count; i++)
                rxq_deinit(mp->rxq + i);
        for (i = 0; i < mp->txq_count; i++)
                txq_deinit(mp->txq + i);

        return 0;
}

static int mv643xx_eth_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);
        int ret;

        if (mp->phy == NULL)
                return -ENOTSUPP;

        ret = phy_mii_ioctl(mp->phy, ifr, cmd);
        if (!ret)
                mv643xx_eth_adjust_link(dev);
        return ret;
}

static int mv643xx_eth_change_mtu(struct net_device *dev, int new_mtu)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);

        if (new_mtu < 64 || new_mtu > 9500)
                return -EINVAL;

        dev->mtu = new_mtu;
        mv643xx_eth_recalc_skb_size(mp);
        tx_set_rate(mp, 1000000000, 16777216);

        if (!netif_running(dev))
                return 0;

        /*
         * Stop and then re-open the interface. This will allocate RX
         * skbs of the new MTU.
         * There is a possible danger that the open will not succeed,
         * due to memory being full.
         */
        mv643xx_eth_stop(dev);
        if (mv643xx_eth_open(dev)) {
                netdev_err(dev,
                           "fatal error on re-opening device after MTU change\n");
        }

        return 0;
}

static void tx_timeout_task(struct work_struct *ugly)
{
        struct mv643xx_eth_private *mp;

        mp = container_of(ugly, struct mv643xx_eth_private, tx_timeout_task);
        if (netif_running(mp->dev)) {
                netif_tx_stop_all_queues(mp->dev);
                port_reset(mp);
                port_start(mp);
                netif_tx_wake_all_queues(mp->dev);
        }
}

static void mv643xx_eth_tx_timeout(struct net_device *dev)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);

        netdev_info(dev, "tx timeout\n");

        schedule_work(&mp->tx_timeout_task);
}

#ifdef CONFIG_NET_POLL_CONTROLLER
static void mv643xx_eth_netpoll(struct net_device *dev)
{
        struct mv643xx_eth_private *mp = netdev_priv(dev);

        wrlp(mp, INT_MASK, 0x00000000);
        rdlp(mp, INT_MASK);

        mv643xx_eth_irq(dev->irq, dev);

        wrlp(mp, INT_MASK, mp->int_mask);
}
#endif


/* platform glue ************************************************************/
static void
mv643xx_eth_conf_mbus_windows(struct mv643xx_eth_shared_private *msp,
                              const struct mbus_dram_target_info *dram)
{
        void __iomem *base = msp->base;
        u32 win_enable;
        u32 win_protect;
        int i;

        for (i = 0; i < 6; i++) {
                writel(0, base + WINDOW_BASE(i));
                writel(0, base + WINDOW_SIZE(i));
                if (i < 4)
                        writel(0, base + WINDOW_REMAP_HIGH(i));
        }

        win_enable = 0x3f;
        win_protect = 0;

        for (i = 0; i < dram->num_cs; i++) {
                const struct mbus_dram_window *cs = dram->cs + i;

                writel((cs->base & 0xffff0000) |
                        (cs->mbus_attr << 8) |
                        dram->mbus_dram_target_id, base + WINDOW_BASE(i));
                writel((cs->size - 1) & 0xffff0000, base + WINDOW_SIZE(i));

                win_enable &= ~(1 << i);
                win_protect |= 3 << (2 * i);
        }

        writel(win_enable, base + WINDOW_BAR_ENABLE);
        msp->win_protect = win_protect;
}

static void infer_hw_params(struct mv643xx_eth_shared_private *msp)
{
        /*
         * Check whether we have a 14-bit coal limit field in bits
         * [21:8], or a 16-bit coal limit in bits [25,21:7] of the
         * SDMA config register.
         */
        writel(0x02000000, msp->base + 0x0400 + SDMA_CONFIG);
        if (readl(msp->base + 0x0400 + SDMA_CONFIG) & 0x02000000)
                msp->extended_rx_coal_limit = 1;
        else
                msp->extended_rx_coal_limit = 0;

        /*
         * Check whether the MAC supports TX rate control, and if
         * yes, whether its associated registers are in the old or
         * the new place.
         */
        writel(1, msp->base + 0x0400 + TX_BW_MTU_MOVED);
        if (readl(msp->base + 0x0400 + TX_BW_MTU_MOVED) & 1) {
                msp->tx_bw_control = TX_BW_CONTROL_NEW_LAYOUT;
        } else {
                writel(7, msp->base + 0x0400 + TX_BW_RATE);
                if (readl(msp->base + 0x0400 + TX_BW_RATE) & 7)
                        msp->tx_bw_control = TX_BW_CONTROL_OLD_LAYOUT;
                else
                        msp->tx_bw_control = TX_BW_CONTROL_ABSENT;
        }
}

#if defined(CONFIG_OF)
static const struct of_device_id mv643xx_eth_shared_ids[] = {
        { .compatible = "marvell,orion-eth", },
        { .compatible = "marvell,kirkwood-eth", },
        { }
};
MODULE_DEVICE_TABLE(of, mv643xx_eth_shared_ids);
#endif

#if defined(CONFIG_OF) && !defined(CONFIG_MV64X60)
#define mv643xx_eth_property(_np, _name, _v)                            \
        do {                                                            \
                u32 tmp;                                                \
                if (!of_property_read_u32(_np, "marvell," _name, &tmp)) \
                        _v = tmp;                                       \
        } while (0)

static struct platform_device *port_platdev[3];

static int mv643xx_eth_shared_of_add_port(struct platform_device *pdev,
                                          struct device_node *pnp)
{
        struct platform_device *ppdev;
        struct mv643xx_eth_platform_data ppd;
        struct resource res;
        const char *mac_addr;
        int ret;
        int dev_num = 0;

        memset(&ppd, 0, sizeof(ppd));
        ppd.shared = pdev;

        memset(&res, 0, sizeof(res));
        if (!of_irq_to_resource(pnp, 0, &res)) {
                dev_err(&pdev->dev, "missing interrupt on %s\n", pnp->name);
                return -EINVAL;
        }

        if (of_property_read_u32(pnp, "reg", &ppd.port_number)) {
                dev_err(&pdev->dev, "missing reg property on %s\n", pnp->name);
                return -EINVAL;
        }

        if (ppd.port_number >= 3) {
                dev_err(&pdev->dev, "invalid reg property on %s\n", pnp->name);
                return -EINVAL;
        }

        while (dev_num < 3 && port_platdev[dev_num])
                dev_num++;

        if (dev_num == 3) {
                dev_err(&pdev->dev, "too many ports registered\n");
                return -EINVAL;
        }

        mac_addr = of_get_mac_address(pnp);
        if (mac_addr)
                memcpy(ppd.mac_addr, mac_addr, ETH_ALEN);

        mv643xx_eth_property(pnp, "tx-queue-size", ppd.tx_queue_size);
        mv643xx_eth_property(pnp, "tx-sram-addr", ppd.tx_sram_addr);
        mv643xx_eth_property(pnp, "tx-sram-size", ppd.tx_sram_size);
        mv643xx_eth_property(pnp, "rx-queue-size", ppd.rx_queue_size);
        mv643xx_eth_property(pnp, "rx-sram-addr", ppd.rx_sram_addr);
        mv643xx_eth_property(pnp, "rx-sram-size", ppd.rx_sram_size);

        ppd.phy_node = of_parse_phandle(pnp, "phy-handle", 0);
        if (!ppd.phy_node) {
                ppd.phy_addr = MV643XX_ETH_PHY_NONE;
                of_property_read_u32(pnp, "speed", &ppd.speed);
                of_property_read_u32(pnp, "duplex", &ppd.duplex);
        }

        ppdev = platform_device_alloc(MV643XX_ETH_NAME, dev_num);
        if (!ppdev)
                return -ENOMEM;
        ppdev->dev.coherent_dma_mask = DMA_BIT_MASK(32);
        ppdev->dev.of_node = pnp;

        ret = platform_device_add_resources(ppdev, &res, 1);
        if (ret)
                goto port_err;

        ret = platform_device_add_data(ppdev, &ppd, sizeof(ppd));
        if (ret)
                goto port_err;

        ret = platform_device_add(ppdev);
        if (ret)
                goto port_err;

        port_platdev[dev_num] = ppdev;

        return 0;

port_err:
        platform_device_put(ppdev);
        return ret;
}

static int mv643xx_eth_shared_of_probe(struct platform_device *pdev)
{
        struct mv643xx_eth_shared_platform_data *pd;
        struct device_node *pnp, *np = pdev->dev.of_node;
        int ret;

        /* bail out if not registered from DT */
        if (!np)
                return 0;

        pd = devm_kzalloc(&pdev->dev, sizeof(*pd), GFP_KERNEL);
        if (!pd)
                return -ENOMEM;
        pdev->dev.platform_data = pd;

        mv643xx_eth_property(np, "tx-checksum-limit", pd->tx_csum_limit);

        for_each_available_child_of_node(np, pnp) {
                ret = mv643xx_eth_shared_of_add_port(pdev, pnp);
                if (ret) {
                        of_node_put(pnp);
                        return ret;
                }
        }
        return 0;
}

static void mv643xx_eth_shared_of_remove(void)
{
        int n;

        for (n = 0; n < 3; n++) {
                platform_device_del(port_platdev[n]);
                port_platdev[n] = NULL;
        }
}
#else
static inline int mv643xx_eth_shared_of_probe(struct platform_device *pdev)
{
        return 0;
}

static inline void mv643xx_eth_shared_of_remove(void)
{
}
#endif

static int mv643xx_eth_shared_probe(struct platform_device *pdev)
{
        static int mv643xx_eth_version_printed;
        struct mv643xx_eth_shared_platform_data *pd;
        struct mv643xx_eth_shared_private *msp;
        const struct mbus_dram_target_info *dram;
        struct resource *res;
        int ret;

        if (!mv643xx_eth_version_printed++)
                pr_notice("MV-643xx 10/100/1000 ethernet driver version %s\n",
                          mv643xx_eth_driver_version);

        res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
        if (res == NULL)
                return -EINVAL;

        msp = devm_kzalloc(&pdev->dev, sizeof(*msp), GFP_KERNEL);
        if (msp == NULL)
                return -ENOMEM;
        platform_set_drvdata(pdev, msp);

        msp->base = devm_ioremap(&pdev->dev, res->start, resource_size(res));
        if (msp->base == NULL)
                return -ENOMEM;

        msp->clk = devm_clk_get(&pdev->dev, NULL);
        if (!IS_ERR(msp->clk))
                clk_prepare_enable(msp->clk);

        /*
         * (Re-)program MBUS remapping windows if we are asked to.
         */
        dram = mv_mbus_dram_info();
        if (dram)
                mv643xx_eth_conf_mbus_windows(msp, dram);

        ret = mv643xx_eth_shared_of_probe(pdev);
        if (ret)
                return ret;
        pd = dev_get_platdata(&pdev->dev);

        msp->tx_csum_limit = (pd != NULL && pd->tx_csum_limit) ?
                                        pd->tx_csum_limit : 9 * 1024;
        infer_hw_params(msp);

        return 0;
}

static int mv643xx_eth_shared_remove(struct platform_device *pdev)
{
        struct mv643xx_eth_shared_private *msp = platform_get_drvdata(pdev);

        mv643xx_eth_shared_of_remove();
        if (!IS_ERR(msp->clk))
                clk_disable_unprepare(msp->clk);
        return 0;
}

static struct platform_driver mv643xx_eth_shared_driver = {
        .probe          = mv643xx_eth_shared_probe,
        .remove         = mv643xx_eth_shared_remove,
        .driver = {
                .name   = MV643XX_ETH_SHARED_NAME,
                .of_match_table = of_match_ptr(mv643xx_eth_shared_ids),
        },
};

static void phy_addr_set(struct mv643xx_eth_private *mp, int phy_addr)
{
        int addr_shift = 5 * mp->port_num;
        u32 data;

        data = rdl(mp, PHY_ADDR);
        data &= ~(0x1f << addr_shift);
        data |= (phy_addr & 0x1f) << addr_shift;
        wrl(mp, PHY_ADDR, data);
}

static int phy_addr_get(struct mv643xx_eth_private *mp)
{
        unsigned int data;

        data = rdl(mp, PHY_ADDR);

        return (data >> (5 * mp->port_num)) & 0x1f;
}

static void set_params(struct mv643xx_eth_private *mp,
                       struct mv643xx_eth_platform_data *pd)
{
        struct net_device *dev = mp->dev;
        unsigned int tx_ring_size;

        if (is_valid_ether_addr(pd->mac_addr))
                memcpy(dev->dev_addr, pd->mac_addr, ETH_ALEN);
        else
                uc_addr_get(mp, dev->dev_addr);

        mp->rx_ring_size = DEFAULT_RX_QUEUE_SIZE;
        if (pd->rx_queue_size)
                mp->rx_ring_size = pd->rx_queue_size;
        mp->rx_desc_sram_addr = pd->rx_sram_addr;
        mp->rx_desc_sram_size = pd->rx_sram_size;

        mp->rxq_count = pd->rx_queue_count ? : 1;

        tx_ring_size = DEFAULT_TX_QUEUE_SIZE;
        if (pd->tx_queue_size)
                tx_ring_size = pd->tx_queue_size;

        mp->tx_ring_size = clamp_t(unsigned int, tx_ring_size,
                                   MV643XX_MAX_SKB_DESCS * 2, 4096);
        if (mp->tx_ring_size != tx_ring_size)
                netdev_warn(dev, "TX queue size set to %u (requested %u)\n",
                            mp->tx_ring_size, tx_ring_size);

        mp->tx_desc_sram_addr = pd->tx_sram_addr;
        mp->tx_desc_sram_size = pd->tx_sram_size;

        mp->txq_count = pd->tx_queue_count ? : 1;
}

static int get_phy_mode(struct mv643xx_eth_private *mp)
{
        struct device *dev = mp->dev->dev.parent;
        int iface = -1;

        if (dev->of_node)
                iface = of_get_phy_mode(dev->of_node);

        /* Historical default if unspecified. We could also read/write
         * the interface state in the PSC1
         */
        if (iface < 0)
                iface = PHY_INTERFACE_MODE_GMII;
        return iface;
}

static struct phy_device *phy_scan(struct mv643xx_eth_private *mp,
                                   int phy_addr)
{
        struct phy_device *phydev;
        int start;
        int num;
        int i;
        char phy_id[MII_BUS_ID_SIZE + 3];

        if (phy_addr == MV643XX_ETH_PHY_ADDR_DEFAULT) {
                start = phy_addr_get(mp) & 0x1f;
                num = 32;