// SPDX-License-Identifier: GPL-2.0+
/*
 * Fast Ethernet Controller (FEC) driver for Motorola MPC8xx.
 * Copyright (c) 1997 Dan Malek (dmalek@jlc.net)
 *
 * Right now, I am very wasteful with the buffers.  I allocate memory
 * pages and then divide them into 2K frame buffers.  This way I know I
 * have buffers large enough to hold one frame within one buffer descriptor.
 * Once I get this working, I will use 64 or 128 byte CPM buffers, which
 * will be much more memory efficient and will easily handle lots of
 * small packets.
 *
 * Much better multiple PHY support by Magnus Damm.
 * Copyright (c) 2000 Ericsson Radio Systems AB.
 *
 * Support for FEC controller of ColdFire processors.
 * Copyright (c) 2001-2005 Greg Ungerer (gerg@snapgear.com)
 *
 * Bug fixes and cleanup by Philippe De Muyter (phdm@macqel.be)
 * Copyright (c) 2004-2006 Macq Electronique SA.
 *
 * Copyright (C) 2010-2011 Freescale Semiconductor, Inc.
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/pm_runtime.h>
#include <linux/ptrace.h>
#include <linux/errno.h>
#include <linux/ioport.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/delay.h>
#include <linux/netdevice.h>
#include <linux/etherdevice.h>
#include <linux/skbuff.h>
#include <linux/in.h>
#include <linux/ip.h>
#include <net/ip.h>
#include <net/selftests.h>
#include <net/tso.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#include <linux/icmp.h>
#include <linux/spinlock.h>
#include <linux/workqueue.h>
#include <linux/bitops.h>
#include <linux/io.h>
#include <linux/irq.h>
#include <linux/clk.h>
#include <linux/crc32.h>
#include <linux/platform_device.h>
#include <linux/mdio.h>
#include <linux/phy.h>
#include <linux/fec.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/of_gpio.h>
#include <linux/of_mdio.h>
#include <linux/of_net.h>
#include <linux/regulator/consumer.h>
#include <linux/if_vlan.h>
#include <linux/pinctrl/consumer.h>
#include <linux/prefetch.h>
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
#include <soc/imx/cpuidle.h>

#include <asm/cacheflush.h>

#include "fec.h"

static void set_multicast_list(struct net_device *ndev);
static void fec_enet_itr_coal_init(struct net_device *ndev);

#define DRIVER_NAME     "fec"

static const u16 fec_enet_vlan_pri_to_queue[8] = {0, 0, 1, 1, 1, 2, 2, 2};

/* Pause frame feild and FIFO threshold */
#define FEC_ENET_FCE    (1 << 5)
#define FEC_ENET_RSEM_V 0x84
#define FEC_ENET_RSFL_V 16
#define FEC_ENET_RAEM_V 0x8
#define FEC_ENET_RAFL_V 0x8
#define FEC_ENET_OPD_V  0xFFF0
#define FEC_MDIO_PM_TIMEOUT  100 /* ms */

struct fec_devinfo {
        u32 quirks;
};

static const struct fec_devinfo fec_imx25_info = {
        .quirks = FEC_QUIRK_USE_GASKET | FEC_QUIRK_MIB_CLEAR |
                  FEC_QUIRK_HAS_FRREG,
};

static const struct fec_devinfo fec_imx27_info = {
        .quirks = FEC_QUIRK_MIB_CLEAR | FEC_QUIRK_HAS_FRREG,
};

static const struct fec_devinfo fec_imx28_info = {
        .quirks = FEC_QUIRK_ENET_MAC | FEC_QUIRK_SWAP_FRAME |
                  FEC_QUIRK_SINGLE_MDIO | FEC_QUIRK_HAS_RACC |
                  FEC_QUIRK_HAS_FRREG | FEC_QUIRK_CLEAR_SETUP_MII |
                  FEC_QUIRK_NO_HARD_RESET,
};

static const struct fec_devinfo fec_imx6q_info = {
        .quirks = FEC_QUIRK_ENET_MAC | FEC_QUIRK_HAS_GBIT |
                  FEC_QUIRK_HAS_BUFDESC_EX | FEC_QUIRK_HAS_CSUM |
                  FEC_QUIRK_HAS_VLAN | FEC_QUIRK_ERR006358 |
                  FEC_QUIRK_HAS_RACC | FEC_QUIRK_CLEAR_SETUP_MII,
};

static const struct fec_devinfo fec_mvf600_info = {
        .quirks = FEC_QUIRK_ENET_MAC | FEC_QUIRK_HAS_RACC,
};

static const struct fec_devinfo fec_imx6x_info = {
        .quirks = FEC_QUIRK_ENET_MAC | FEC_QUIRK_HAS_GBIT |
                  FEC_QUIRK_HAS_BUFDESC_EX | FEC_QUIRK_HAS_CSUM |
                  FEC_QUIRK_HAS_VLAN | FEC_QUIRK_HAS_AVB |
                  FEC_QUIRK_ERR007885 | FEC_QUIRK_BUG_CAPTURE |
                  FEC_QUIRK_HAS_RACC | FEC_QUIRK_HAS_COALESCE |
                  FEC_QUIRK_CLEAR_SETUP_MII | FEC_QUIRK_HAS_MULTI_QUEUES,
};

static const struct fec_devinfo fec_imx6ul_info = {
        .quirks = FEC_QUIRK_ENET_MAC | FEC_QUIRK_HAS_GBIT |
                  FEC_QUIRK_HAS_BUFDESC_EX | FEC_QUIRK_HAS_CSUM |
                  FEC_QUIRK_HAS_VLAN | FEC_QUIRK_ERR007885 |
                  FEC_QUIRK_BUG_CAPTURE | FEC_QUIRK_HAS_RACC |
                  FEC_QUIRK_HAS_COALESCE | FEC_QUIRK_CLEAR_SETUP_MII,
};

static struct platform_device_id fec_devtype[] = {
        {
                /* keep it for coldfire */
                .name = DRIVER_NAME,
                .driver_data = 0,
        }, {
                .name = "imx25-fec",
                .driver_data = (kernel_ulong_t)&fec_imx25_info,
        }, {
                .name = "imx27-fec",
                .driver_data = (kernel_ulong_t)&fec_imx27_info,
        }, {
                .name = "imx28-fec",
                .driver_data = (kernel_ulong_t)&fec_imx28_info,
        }, {
                .name = "imx6q-fec",
                .driver_data = (kernel_ulong_t)&fec_imx6q_info,
        }, {
                .name = "mvf600-fec",
                .driver_data = (kernel_ulong_t)&fec_mvf600_info,
        }, {
                .name = "imx6sx-fec",
                .driver_data = (kernel_ulong_t)&fec_imx6x_info,
        }, {
                .name = "imx6ul-fec",
                .driver_data = (kernel_ulong_t)&fec_imx6ul_info,
        }, {
                /* sentinel */
        }
};
MODULE_DEVICE_TABLE(platform, fec_devtype);

enum imx_fec_type {
        IMX25_FEC = 1,  /* runs on i.mx25/50/53 */
        IMX27_FEC,      /* runs on i.mx27/35/51 */
        IMX28_FEC,
        IMX6Q_FEC,
        MVF600_FEC,
        IMX6SX_FEC,
        IMX6UL_FEC,
};

static const struct of_device_id fec_dt_ids[] = {
        { .compatible = "fsl,imx25-fec", .data = &fec_devtype[IMX25_FEC], },
        { .compatible = "fsl,imx27-fec", .data = &fec_devtype[IMX27_FEC], },
        { .compatible = "fsl,imx28-fec", .data = &fec_devtype[IMX28_FEC], },
        { .compatible = "fsl,imx6q-fec", .data = &fec_devtype[IMX6Q_FEC], },
        { .compatible = "fsl,mvf600-fec", .data = &fec_devtype[MVF600_FEC], },
        { .compatible = "fsl,imx6sx-fec", .data = &fec_devtype[IMX6SX_FEC], },
        { .compatible = "fsl,imx6ul-fec", .data = &fec_devtype[IMX6UL_FEC], },
        { /* sentinel */ }
};
MODULE_DEVICE_TABLE(of, fec_dt_ids);

static unsigned char macaddr[ETH_ALEN];
module_param_array(macaddr, byte, NULL, 0);
MODULE_PARM_DESC(macaddr, "FEC Ethernet MAC address");

#if defined(CONFIG_M5272)
/*
 * Some hardware gets it MAC address out of local flash memory.
 * if this is non-zero then assume it is the address to get MAC from.
 */
#if defined(CONFIG_NETtel)
#define FEC_FLASHMAC    0xf0006006
#elif defined(CONFIG_GILBARCONAP) || defined(CONFIG_SCALES)
#define FEC_FLASHMAC    0xf0006000
#elif defined(CONFIG_CANCam)
#define FEC_FLASHMAC    0xf0020000
#elif defined (CONFIG_M5272C3)
#define FEC_FLASHMAC    (0xffe04000 + 4)
#elif defined(CONFIG_MOD5272)
#define FEC_FLASHMAC    0xffc0406b
#else
#define FEC_FLASHMAC    0
#endif
#endif /* CONFIG_M5272 */

/* The FEC stores dest/src/type/vlan, data, and checksum for receive packets.
 *
 * 2048 byte skbufs are allocated. However, alignment requirements
 * varies between FEC variants. Worst case is 64, so round down by 64.
 */
#define PKT_MAXBUF_SIZE         (round_down(2048 - 64, 64))
#define PKT_MINBUF_SIZE         64

/* FEC receive acceleration */
#define FEC_RACC_IPDIS          (1 << 1)
#define FEC_RACC_PRODIS         (1 << 2)
#define FEC_RACC_SHIFT16        BIT(7)
#define FEC_RACC_OPTIONS        (FEC_RACC_IPDIS | FEC_RACC_PRODIS)

/* MIB Control Register */
#define FEC_MIB_CTRLSTAT_DISABLE        BIT(31)

/*
 * The 5270/5271/5280/5282/532x RX control register also contains maximum frame
 * size bits. Other FEC hardware does not, so we need to take that into
 * account when setting it.
 */
#if defined(CONFIG_M523x) || defined(CONFIG_M527x) || defined(CONFIG_M528x) || \
    defined(CONFIG_M520x) || defined(CONFIG_M532x) || defined(CONFIG_ARM) || \
    defined(CONFIG_ARM64)
#define OPT_FRAME_SIZE  (PKT_MAXBUF_SIZE << 16)
#else
#define OPT_FRAME_SIZE  0
#endif

/* FEC MII MMFR bits definition */
#define FEC_MMFR_ST             (1 << 30)
#define FEC_MMFR_ST_C45         (0)
#define FEC_MMFR_OP_READ        (2 << 28)
#define FEC_MMFR_OP_READ_C45    (3 << 28)
#define FEC_MMFR_OP_WRITE       (1 << 28)
#define FEC_MMFR_OP_ADDR_WRITE  (0)
#define FEC_MMFR_PA(v)          ((v & 0x1f) << 23)
#define FEC_MMFR_RA(v)          ((v & 0x1f) << 18)
#define FEC_MMFR_TA             (2 << 16)
#define FEC_MMFR_DATA(v)        (v & 0xffff)
/* FEC ECR bits definition */
#define FEC_ECR_MAGICEN         (1 << 2)
#define FEC_ECR_SLEEP           (1 << 3)

#define FEC_MII_TIMEOUT         30000 /* us */

/* Transmitter timeout */
#define TX_TIMEOUT (2 * HZ)

#define FEC_PAUSE_FLAG_AUTONEG  0x1
#define FEC_PAUSE_FLAG_ENABLE   0x2
#define FEC_WOL_HAS_MAGIC_PACKET        (0x1 << 0)
#define FEC_WOL_FLAG_ENABLE             (0x1 << 1)
#define FEC_WOL_FLAG_SLEEP_ON           (0x1 << 2)

#define COPYBREAK_DEFAULT       256

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

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

static int mii_cnt;

static struct bufdesc *fec_enet_get_nextdesc(struct bufdesc *bdp,
                                             struct bufdesc_prop *bd)
{
        return (bdp >= bd->last) ? bd->base
                        : (struct bufdesc *)(((void *)bdp) + bd->dsize);
}

static struct bufdesc *fec_enet_get_prevdesc(struct bufdesc *bdp,
                                             struct bufdesc_prop *bd)
{
        return (bdp <= bd->base) ? bd->last
                        : (struct bufdesc *)(((void *)bdp) - bd->dsize);
}

static int fec_enet_get_bd_index(struct bufdesc *bdp,
                                 struct bufdesc_prop *bd)
{
        return ((const char *)bdp - (const char *)bd->base) >> bd->dsize_log2;
}

static int fec_enet_get_free_txdesc_num(struct fec_enet_priv_tx_q *txq)
{
        int entries;

        entries = (((const char *)txq->dirty_tx -
                        (const char *)txq->bd.cur) >> txq->bd.dsize_log2) - 1;

        return entries >= 0 ? entries : entries + txq->bd.ring_size;
}

static void swap_buffer(void *bufaddr, int len)
{
        int i;
        unsigned int *buf = bufaddr;

        for (i = 0; i < len; i += 4, buf++)
                swab32s(buf);
}

static void swap_buffer2(void *dst_buf, void *src_buf, int len)
{
        int i;
        unsigned int *src = src_buf;
        unsigned int *dst = dst_buf;

        for (i = 0; i < len; i += 4, src++, dst++)
                *dst = swab32p(src);
}

static void fec_dump(struct net_device *ndev)
{
        struct fec_enet_private *fep = netdev_priv(ndev);
        struct bufdesc *bdp;
        struct fec_enet_priv_tx_q *txq;
        int index = 0;

        netdev_info(ndev, "TX ring dump\n");
        pr_info("Nr     SC     addr       len  SKB\n");

        txq = fep->tx_queue[0];
        bdp = txq->bd.base;

        do {
                pr_info("%3u %c%c 0x%04x 0x%08x %4u %p\n",
                        index,
                        bdp == txq->bd.cur ? 'S' : ' ',
                        bdp == txq->dirty_tx ? 'H' : ' ',
                        fec16_to_cpu(bdp->cbd_sc),
                        fec32_to_cpu(bdp->cbd_bufaddr),
                        fec16_to_cpu(bdp->cbd_datlen),
                        txq->tx_skbuff[index]);
                bdp = fec_enet_get_nextdesc(bdp, &txq->bd);
                index++;
        } while (bdp != txq->bd.base);
}

static inline bool is_ipv4_pkt(struct sk_buff *skb)
{
        return skb->protocol == htons(ETH_P_IP) && ip_hdr(skb)->version == 4;
}

static int
fec_enet_clear_csum(struct sk_buff *skb, struct net_device *ndev)
{
        /* Only run for packets requiring a checksum. */
        if (skb->ip_summed != CHECKSUM_PARTIAL)
                return 0;

        if (unlikely(skb_cow_head(skb, 0)))
                return -1;

        if (is_ipv4_pkt(skb))
                ip_hdr(skb)->check = 0;
        *(__sum16 *)(skb->head + skb->csum_start + skb->csum_offset) = 0;

        return 0;
}

static struct bufdesc *
fec_enet_txq_submit_frag_skb(struct fec_enet_priv_tx_q *txq,
                             struct sk_buff *skb,
                             struct net_device *ndev)
{
        struct fec_enet_private *fep = netdev_priv(ndev);
        struct bufdesc *bdp = txq->bd.cur;
        struct bufdesc_ex *ebdp;
        int nr_frags = skb_shinfo(skb)->nr_frags;
        int frag, frag_len;
        unsigned short status;
        unsigned int estatus = 0;
        skb_frag_t *this_frag;
        unsigned int index;
        void *bufaddr;
        dma_addr_t addr;
        int i;

        for (frag = 0; frag < nr_frags; frag++) {
                this_frag = &skb_shinfo(skb)->frags[frag];
                bdp = fec_enet_get_nextdesc(bdp, &txq->bd);
                ebdp = (struct bufdesc_ex *)bdp;

                status = fec16_to_cpu(bdp->cbd_sc);
                status &= ~BD_ENET_TX_STATS;
                status |= (BD_ENET_TX_TC | BD_ENET_TX_READY);
                frag_len = skb_frag_size(&skb_shinfo(skb)->frags[frag]);

                /* Handle the last BD specially */
                if (frag == nr_frags - 1) {
                        status |= (BD_ENET_TX_INTR | BD_ENET_TX_LAST);
                        if (fep->bufdesc_ex) {
                                estatus |= BD_ENET_TX_INT;
                                if (unlikely(skb_shinfo(skb)->tx_flags &
                                        SKBTX_HW_TSTAMP && fep->hwts_tx_en))
                                        estatus |= BD_ENET_TX_TS;
                        }
                }

                if (fep->bufdesc_ex) {
                        if (fep->quirks & FEC_QUIRK_HAS_AVB)
                                estatus |= FEC_TX_BD_FTYPE(txq->bd.qid);
                        if (skb->ip_summed == CHECKSUM_PARTIAL)
                                estatus |= BD_ENET_TX_PINS | BD_ENET_TX_IINS;

                        ebdp->cbd_bdu = 0;
                        ebdp->cbd_esc = cpu_to_fec32(estatus);
                }

                bufaddr = skb_frag_address(this_frag);

                index = fec_enet_get_bd_index(bdp, &txq->bd);
                if (((unsigned long) bufaddr) & fep->tx_align ||
                        fep->quirks & FEC_QUIRK_SWAP_FRAME) {
                        memcpy(txq->tx_bounce[index], bufaddr, frag_len);
                        bufaddr = txq->tx_bounce[index];

                        if (fep->quirks & FEC_QUIRK_SWAP_FRAME)
                                swap_buffer(bufaddr, frag_len);
                }

                addr = dma_map_single(&fep->pdev->dev, bufaddr, frag_len,
                                      DMA_TO_DEVICE);
                if (dma_mapping_error(&fep->pdev->dev, addr)) {
                        if (net_ratelimit())
                                netdev_err(ndev, "Tx DMA memory map failed\n");
                        goto dma_mapping_error;
                }

                bdp->cbd_bufaddr = cpu_to_fec32(addr);
                bdp->cbd_datlen = cpu_to_fec16(frag_len);
                /* Make sure the updates to rest of the descriptor are
                 * performed before transferring ownership.
                 */
                wmb();
                bdp->cbd_sc = cpu_to_fec16(status);
        }

        return bdp;
dma_mapping_error:
        bdp = txq->bd.cur;
        for (i = 0; i < frag; i++) {
                bdp = fec_enet_get_nextdesc(bdp, &txq->bd);
                dma_unmap_single(&fep->pdev->dev, fec32_to_cpu(bdp->cbd_bufaddr),
                                 fec16_to_cpu(bdp->cbd_datlen), DMA_TO_DEVICE);
        }
        return ERR_PTR(-ENOMEM);
}

static int fec_enet_txq_submit_skb(struct fec_enet_priv_tx_q *txq,
                                   struct sk_buff *skb, struct net_device *ndev)
{
        struct fec_enet_private *fep = netdev_priv(ndev);
        int nr_frags = skb_shinfo(skb)->nr_frags;
        struct bufdesc *bdp, *last_bdp;
        void *bufaddr;
        dma_addr_t addr;
        unsigned short status;
        unsigned short buflen;
        unsigned int estatus = 0;
        unsigned int index;
        int entries_free;

        entries_free = fec_enet_get_free_txdesc_num(txq);
        if (entries_free < MAX_SKB_FRAGS + 1) {
                dev_kfree_skb_any(skb);
                if (net_ratelimit())
                        netdev_err(ndev, "NOT enough BD for SG!\n");
                return NETDEV_TX_OK;
        }

        /* Protocol checksum off-load for TCP and UDP. */
        if (fec_enet_clear_csum(skb, ndev)) {
                dev_kfree_skb_any(skb);
                return NETDEV_TX_OK;
        }

        /* Fill in a Tx ring entry */
        bdp = txq->bd.cur;
        last_bdp = bdp;
        status = fec16_to_cpu(bdp->cbd_sc);
        status &= ~BD_ENET_TX_STATS;

        /* Set buffer length and buffer pointer */
        bufaddr = skb->data;
        buflen = skb_headlen(skb);

        index = fec_enet_get_bd_index(bdp, &txq->bd);
        if (((unsigned long) bufaddr) & fep->tx_align ||
                fep->quirks & FEC_QUIRK_SWAP_FRAME) {
                memcpy(txq->tx_bounce[index], skb->data, buflen);
                bufaddr = txq->tx_bounce[index];

                if (fep->quirks & FEC_QUIRK_SWAP_FRAME)
                        swap_buffer(bufaddr, buflen);
        }

        /* Push the data cache so the CPM does not get stale memory data. */
        addr = dma_map_single(&fep->pdev->dev, bufaddr, buflen, DMA_TO_DEVICE);
        if (dma_mapping_error(&fep->pdev->dev, addr)) {
                dev_kfree_skb_any(skb);
                if (net_ratelimit())
                        netdev_err(ndev, "Tx DMA memory map failed\n");
                return NETDEV_TX_OK;
        }

        if (nr_frags) {
                last_bdp = fec_enet_txq_submit_frag_skb(txq, skb, ndev);
                if (IS_ERR(last_bdp)) {
                        dma_unmap_single(&fep->pdev->dev, addr,
                                         buflen, DMA_TO_DEVICE);
                        dev_kfree_skb_any(skb);
                        return NETDEV_TX_OK;
                }
        } else {
                status |= (BD_ENET_TX_INTR | BD_ENET_TX_LAST);
                if (fep->bufdesc_ex) {
                        estatus = BD_ENET_TX_INT;
                        if (unlikely(skb_shinfo(skb)->tx_flags &
                                SKBTX_HW_TSTAMP && fep->hwts_tx_en))
                                estatus |= BD_ENET_TX_TS;
                }
        }
        bdp->cbd_bufaddr = cpu_to_fec32(addr);
        bdp->cbd_datlen = cpu_to_fec16(buflen);

        if (fep->bufdesc_ex) {

                struct bufdesc_ex *ebdp = (struct bufdesc_ex *)bdp;

                if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP &&
                        fep->hwts_tx_en))
                        skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;

                if (fep->quirks & FEC_QUIRK_HAS_AVB)
                        estatus |= FEC_TX_BD_FTYPE(txq->bd.qid);

                if (skb->ip_summed == CHECKSUM_PARTIAL)
                        estatus |= BD_ENET_TX_PINS | BD_ENET_TX_IINS;

                ebdp->cbd_bdu = 0;
                ebdp->cbd_esc = cpu_to_fec32(estatus);
        }

        index = fec_enet_get_bd_index(last_bdp, &txq->bd);
        /* Save skb pointer */
        txq->tx_skbuff[index] = skb;

        /* Make sure the updates to rest of the descriptor are performed before
         * transferring ownership.
         */
        wmb();

        /* Send it on its way.  Tell FEC it's ready, interrupt when done,
         * it's the last BD of the frame, and to put the CRC on the end.
         */
        status |= (BD_ENET_TX_READY | BD_ENET_TX_TC);
        bdp->cbd_sc = cpu_to_fec16(status);

        /* If this was the last BD in the ring, start at the beginning again. */
        bdp = fec_enet_get_nextdesc(last_bdp, &txq->bd);

        skb_tx_timestamp(skb);

        /* Make sure the update to bdp and tx_skbuff are performed before
         * txq->bd.cur.
         */
        wmb();
        txq->bd.cur = bdp;

        /* Trigger transmission start */
        writel(0, txq->bd.reg_desc_active);

        return 0;
}

static int
fec_enet_txq_put_data_tso(struct fec_enet_priv_tx_q *txq, struct sk_buff *skb,
                          struct net_device *ndev,
                          struct bufdesc *bdp, int index, char *data,
                          int size, bool last_tcp, bool is_last)
{
        struct fec_enet_private *fep = netdev_priv(ndev);
        struct bufdesc_ex *ebdp = container_of(bdp, struct bufdesc_ex, desc);
        unsigned short status;
        unsigned int estatus = 0;
        dma_addr_t addr;

        status = fec16_to_cpu(bdp->cbd_sc);
        status &= ~BD_ENET_TX_STATS;

        status |= (BD_ENET_TX_TC | BD_ENET_TX_READY);

        if (((unsigned long) data) & fep->tx_align ||
                fep->quirks & FEC_QUIRK_SWAP_FRAME) {
                memcpy(txq->tx_bounce[index], data, size);
                data = txq->tx_bounce[index];

                if (fep->quirks & FEC_QUIRK_SWAP_FRAME)
                        swap_buffer(data, size);
        }

        addr = dma_map_single(&fep->pdev->dev, data, size, DMA_TO_DEVICE);
        if (dma_mapping_error(&fep->pdev->dev, addr)) {
                dev_kfree_skb_any(skb);
                if (net_ratelimit())
                        netdev_err(ndev, "Tx DMA memory map failed\n");
                return NETDEV_TX_BUSY;
        }

        bdp->cbd_datlen = cpu_to_fec16(size);
        bdp->cbd_bufaddr = cpu_to_fec32(addr);

        if (fep->bufdesc_ex) {
                if (fep->quirks & FEC_QUIRK_HAS_AVB)
                        estatus |= FEC_TX_BD_FTYPE(txq->bd.qid);
                if (skb->ip_summed == CHECKSUM_PARTIAL)
                        estatus |= BD_ENET_TX_PINS | BD_ENET_TX_IINS;
                ebdp->cbd_bdu = 0;
                ebdp->cbd_esc = cpu_to_fec32(estatus);
        }

        /* Handle the last BD specially */
        if (last_tcp)
                status |= (BD_ENET_TX_LAST | BD_ENET_TX_TC);
        if (is_last) {
                status |= BD_ENET_TX_INTR;
                if (fep->bufdesc_ex)
                        ebdp->cbd_esc |= cpu_to_fec32(BD_ENET_TX_INT);
        }

        bdp->cbd_sc = cpu_to_fec16(status);

        return 0;
}

static int
fec_enet_txq_put_hdr_tso(struct fec_enet_priv_tx_q *txq,
                         struct sk_buff *skb, struct net_device *ndev,
                         struct bufdesc *bdp, int index)
{
        struct fec_enet_private *fep = netdev_priv(ndev);
        int hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);
        struct bufdesc_ex *ebdp = container_of(bdp, struct bufdesc_ex, desc);
        void *bufaddr;
        unsigned long dmabuf;
        unsigned short status;
        unsigned int estatus = 0;

        status = fec16_to_cpu(bdp->cbd_sc);
        status &= ~BD_ENET_TX_STATS;
        status |= (BD_ENET_TX_TC | BD_ENET_TX_READY);

        bufaddr = txq->tso_hdrs + index * TSO_HEADER_SIZE;
        dmabuf = txq->tso_hdrs_dma + index * TSO_HEADER_SIZE;
        if (((unsigned long)bufaddr) & fep->tx_align ||
                fep->quirks & FEC_QUIRK_SWAP_FRAME) {
                memcpy(txq->tx_bounce[index], skb->data, hdr_len);
                bufaddr = txq->tx_bounce[index];

                if (fep->quirks & FEC_QUIRK_SWAP_FRAME)
                        swap_buffer(bufaddr, hdr_len);

                dmabuf = dma_map_single(&fep->pdev->dev, bufaddr,
                                        hdr_len, DMA_TO_DEVICE);
                if (dma_mapping_error(&fep->pdev->dev, dmabuf)) {
                        dev_kfree_skb_any(skb);
                        if (net_ratelimit())
                                netdev_err(ndev, "Tx DMA memory map failed\n");
                        return NETDEV_TX_BUSY;
                }
        }

        bdp->cbd_bufaddr = cpu_to_fec32(dmabuf);
        bdp->cbd_datlen = cpu_to_fec16(hdr_len);

        if (fep->bufdesc_ex) {
                if (fep->quirks & FEC_QUIRK_HAS_AVB)
                        estatus |= FEC_TX_BD_FTYPE(txq->bd.qid);
                if (skb->ip_summed == CHECKSUM_PARTIAL)
                        estatus |= BD_ENET_TX_PINS | BD_ENET_TX_IINS;
                ebdp->cbd_bdu = 0;
                ebdp->cbd_esc = cpu_to_fec32(estatus);
        }

        bdp->cbd_sc = cpu_to_fec16(status);

        return 0;
}

static int fec_enet_txq_submit_tso(struct fec_enet_priv_tx_q *txq,
                                   struct sk_buff *skb,
                                   struct net_device *ndev)
{
        struct fec_enet_private *fep = netdev_priv(ndev);
        int hdr_len, total_len, data_left;
        struct bufdesc *bdp = txq->bd.cur;
        struct tso_t tso;
        unsigned int index = 0;
        int ret;

        if (tso_count_descs(skb) >= fec_enet_get_free_txdesc_num(txq)) {
                dev_kfree_skb_any(skb);
                if (net_ratelimit())
                        netdev_err(ndev, "NOT enough BD for TSO!\n");
                return NETDEV_TX_OK;
        }

        /* Protocol checksum off-load for TCP and UDP. */
        if (fec_enet_clear_csum(skb, ndev)) {
                dev_kfree_skb_any(skb);
                return NETDEV_TX_OK;
        }

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

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

                index = fec_enet_get_bd_index(bdp, &txq->bd);
                data_left = min_t(int, skb_shinfo(skb)->gso_size, total_len);
                total_len -= data_left;

                /* prepare packet headers: MAC + IP + TCP */
                hdr = txq->tso_hdrs + index * TSO_HEADER_SIZE;
                tso_build_hdr(skb, hdr, &tso, data_left, total_len == 0);
                ret = fec_enet_txq_put_hdr_tso(txq, skb, ndev, bdp, index);
                if (ret)
                        goto err_release;

                while (data_left > 0) {
                        int size;

                        size = min_t(int, tso.size, data_left);
                        bdp = fec_enet_get_nextdesc(bdp, &txq->bd);
                        index = fec_enet_get_bd_index(bdp, &txq->bd);
                        ret = fec_enet_txq_put_data_tso(txq, skb, ndev,
                                                        bdp, index,
                                                        tso.data, size,
                                                        size == data_left,
                                                        total_len == 0);
                        if (ret)
                                goto err_release;

                        data_left -= size;
                        tso_build_data(skb, &tso, size);
                }

                bdp = fec_enet_get_nextdesc(bdp, &txq->bd);
        }

        /* Save skb pointer */
        txq->tx_skbuff[index] = skb;

        skb_tx_timestamp(skb);
        txq->bd.cur = bdp;

        /* Trigger transmission start */
        if (!(fep->quirks & FEC_QUIRK_ERR007885) ||
            !readl(txq->bd.reg_desc_active) ||
            !readl(txq->bd.reg_desc_active) ||
            !readl(txq->bd.reg_desc_active) ||
            !readl(txq->bd.reg_desc_active))
                writel(0, txq->bd.reg_desc_active);

        return 0;

err_release:
        /* TODO: Release all used data descriptors for TSO */
        return ret;
}

static netdev_tx_t
fec_enet_start_xmit(struct sk_buff *skb, struct net_device *ndev)
{
        struct fec_enet_private *fep = netdev_priv(ndev);
        int entries_free;
        unsigned short queue;
        struct fec_enet_priv_tx_q *txq;
        struct netdev_queue *nq;
        int ret;

        queue = skb_get_queue_mapping(skb);
        txq = fep->tx_queue[queue];
        nq = netdev_get_tx_queue(ndev, queue);

        if (skb_is_gso(skb))
                ret = fec_enet_txq_submit_tso(txq, skb, ndev);
        else
                ret = fec_enet_txq_submit_skb(txq, skb, ndev);
        if (ret)
                return ret;

        entries_free = fec_enet_get_free_txdesc_num(txq);
        if (entries_free <= txq->tx_stop_threshold)
                netif_tx_stop_queue(nq);

        return NETDEV_TX_OK;
}

/* Init RX & TX buffer descriptors
 */
static void fec_enet_bd_init(struct net_device *dev)
{
        struct fec_enet_private *fep = netdev_priv(dev);
        struct fec_enet_priv_tx_q *txq;
        struct fec_enet_priv_rx_q *rxq;
        struct bufdesc *bdp;
        unsigned int i;
        unsigned int q;

        for (q = 0; q < fep->num_rx_queues; q++) {
                /* Initialize the receive buffer descriptors. */
                rxq = fep->rx_queue[q];
                bdp = rxq->bd.base;

                for (i = 0; i < rxq->bd.ring_size; i++) {

                        /* Initialize the BD for every fragment in the page. */
                        if (bdp->cbd_bufaddr)
                                bdp->cbd_sc = cpu_to_fec16(BD_ENET_RX_EMPTY);
                        else
                                bdp->cbd_sc = cpu_to_fec16(0);
                        bdp = fec_enet_get_nextdesc(bdp, &rxq->bd);
                }

                /* Set the last buffer to wrap */
                bdp = fec_enet_get_prevdesc(bdp, &rxq->bd);
                bdp->cbd_sc |= cpu_to_fec16(BD_SC_WRAP);

                rxq->bd.cur = rxq->bd.base;
        }

        for (q = 0; q < fep->num_tx_queues; q++) {
                /* ...and the same for transmit */
                txq = fep->tx_queue[q];
                bdp = txq->bd.base;
                txq->bd.cur = bdp;

                for (i = 0; i < txq->bd.ring_size; i++) {
                        /* Initialize the BD for every fragment in the page. */
                        bdp->cbd_sc = cpu_to_fec16(0);
                        if (bdp->cbd_bufaddr &&
                            !IS_TSO_HEADER(txq, fec32_to_cpu(bdp->cbd_bufaddr)))
                                dma_unmap_single(&fep->pdev->dev,
                                                 fec32_to_cpu(bdp->cbd_bufaddr),
                                                 fec16_to_cpu(bdp->cbd_datlen),
                                                 DMA_TO_DEVICE);
                        if (txq->tx_skbuff[i]) {
                                dev_kfree_skb_any(txq->tx_skbuff[i]);
                                txq->tx_skbuff[i] = NULL;
                        }
                        bdp->cbd_bufaddr = cpu_to_fec32(0);
                        bdp = fec_enet_get_nextdesc(bdp, &txq->bd);
                }

                /* Set the last buffer to wrap */
                bdp = fec_enet_get_prevdesc(bdp, &txq->bd);
                bdp->cbd_sc |= cpu_to_fec16(BD_SC_WRAP);
                txq->dirty_tx = bdp;
        }
}

static void fec_enet_active_rxring(struct net_device *ndev)
{
        struct fec_enet_private *fep = netdev_priv(ndev);
        int i;

        for (i = 0; i < fep->num_rx_queues; i++)
                writel(0, fep->rx_queue[i]->bd.reg_desc_active);
}

static void fec_enet_enable_ring(struct net_device *ndev)
{
        struct fec_enet_private *fep = netdev_priv(ndev);
        struct fec_enet_priv_tx_q *txq;
        struct fec_enet_priv_rx_q *rxq;
        int i;

        for (i = 0; i < fep->num_rx_queues; i++) {
                rxq = fep->rx_queue[i];
                writel(rxq->bd.dma, fep->hwp + FEC_R_DES_START(i));
                writel(PKT_MAXBUF_SIZE, fep->hwp + FEC_R_BUFF_SIZE(i));

                /* enable DMA1/2 */
                if (i)
                        writel(RCMR_MATCHEN | RCMR_CMP(i),
                               fep->hwp + FEC_RCMR(i));
        }

        for (i = 0; i < fep->num_tx_queues; i++) {
                txq = fep->tx_queue[i];
                writel(txq->bd.dma, fep->hwp + FEC_X_DES_START(i));

                /* enable DMA1/2 */
                if (i)
                        writel(DMA_CLASS_EN | IDLE_SLOPE(i),
                               fep->hwp + FEC_DMA_CFG(i));
        }
}

static void fec_enet_reset_skb(struct net_device *ndev)
{
        struct fec_enet_private *fep = netdev_priv(ndev);
        struct fec_enet_priv_tx_q *txq;
        int i, j;

        for (i = 0; i < fep->num_tx_queues; i++) {
                txq = fep->tx_queue[i];

                for (j = 0; j < txq->bd.ring_size; j++) {
                        if (txq->tx_skbuff[j]) {
                                dev_kfree_skb_any(txq->tx_skbuff[j]);
                                txq->tx_skbuff[j] = NULL;
                        }
                }
        }
}

/*
 * This function is called to start or restart the FEC during a link
 * change, transmit timeout, or to reconfigure the FEC.  The network
 * packet processing for this device must be stopped before this call.
 */
static void
fec_restart(struct net_device *ndev)
{
        struct fec_enet_private *fep = netdev_priv(ndev);
        u32 temp_mac[2];
        u32 rcntl = OPT_FRAME_SIZE | 0x04;
        u32 ecntl = 0x2; /* ETHEREN */

        /* Whack a reset.  We should wait for this.
         * For i.MX6SX SOC, enet use AXI bus, we use disable MAC
         * instead of reset MAC itself.
         */
        if (fep->quirks & FEC_QUIRK_HAS_MULTI_QUEUES ||
            ((fep->quirks & FEC_QUIRK_NO_HARD_RESET) && fep->link)) {
                writel(0, fep->hwp + FEC_ECNTRL);
        } else {
                writel(1, fep->hwp + FEC_ECNTRL);
                udelay(10);
        }

        /*
         * enet-mac reset will reset mac address registers too,
         * so need to reconfigure it.
         */
        memcpy(&temp_mac, ndev->dev_addr, ETH_ALEN);
        writel((__force u32)cpu_to_be32(temp_mac[0]),
               fep->hwp + FEC_ADDR_LOW);
        writel((__force u32)cpu_to_be32(temp_mac[1]),
               fep->hwp + FEC_ADDR_HIGH);

        /* Clear any outstanding interrupt, except MDIO. */
        writel((0xffffffff & ~FEC_ENET_MII), fep->hwp + FEC_IEVENT);

        fec_enet_bd_init(ndev);

        fec_enet_enable_ring(ndev);

        /* Reset tx SKB buffers. */
        fec_enet_reset_skb(ndev);

        /* Enable MII mode */
        if (fep->full_duplex == DUPLEX_FULL) {
                /* FD enable */
                writel(0x04, fep->hwp + FEC_X_CNTRL);
        } else {
                /* No Rcv on Xmit */
                rcntl |= 0x02;
                writel(0x0, fep->hwp + FEC_X_CNTRL);
        }

        /* Set MII speed */
        writel(fep->phy_speed, fep->hwp + FEC_MII_SPEED);

#if !defined(CONFIG_M5272)
        if (fep->quirks & FEC_QUIRK_HAS_RACC) {
                u32 val = readl(fep->hwp + FEC_RACC);

                /* align IP header */
                val |= FEC_RACC_SHIFT16;
                if (fep->csum_flags & FLAG_RX_CSUM_ENABLED)
                        /* set RX checksum */
                        val |= FEC_RACC_OPTIONS;
                else
                        val &= ~FEC_RACC_OPTIONS;
                writel(val, fep->hwp + FEC_RACC);
                writel(PKT_MAXBUF_SIZE, fep->hwp + FEC_FTRL);
        }
#endif

        /*
         * The phy interface and speed need to get configured
         * differently on enet-mac.
         */
        if (fep->quirks & FEC_QUIRK_ENET_MAC) {
                /* Enable flow control and length check */
                rcntl |= 0x40000000 | 0x00000020;

                /* RGMII, RMII or MII */
                if (fep->phy_interface == PHY_INTERFACE_MODE_RGMII ||
                    fep->phy_interface == PHY_INTERFACE_MODE_RGMII_ID ||
                    fep->phy_interface == PHY_INTERFACE_MODE_RGMII_RXID ||
                    fep->phy_interface == PHY_INTERFACE_MODE_RGMII_TXID)
                        rcntl |= (1 << 6);
                else if (fep->phy_interface == PHY_INTERFACE_MODE_RMII)
                        rcntl |= (1 << 8);
                else
                        rcntl &= ~(1 << 8);

                /* 1G, 100M or 10M */
                if (ndev->phydev) {
                        if (ndev->phydev->speed == SPEED_1000)
                                ecntl |= (1 << 5);
                        else if (ndev->phydev->speed == SPEED_100)
                                rcntl &= ~(1 << 9);
                        else
                                rcntl |= (1 << 9);
                }
        } else {
#ifdef FEC_MIIGSK_ENR
                if (fep->quirks & FEC_QUIRK_USE_GASKET) {
                        u32 cfgr;
                        /* disable the gasket and wait */
                        writel(0, fep->hwp + FEC_MIIGSK_ENR);
                        while (readl(fep->hwp + FEC_MIIGSK_ENR) & 4)
                                udelay(1);

                        /*
                         * configure the gasket:
                         *   RMII, 50 MHz, no loopback, no echo
                         *   MII, 25 MHz, no loopback, no echo
                         */
                        cfgr = (fep->phy_interface == PHY_INTERFACE_MODE_RMII)
                                ? BM_MIIGSK_CFGR_RMII : BM_MIIGSK_CFGR_MII;
                        if (ndev->phydev && ndev->phydev->speed == SPEED_10)
                                cfgr |= BM_MIIGSK_CFGR_FRCONT_10M;
                        writel(cfgr, fep->hwp + FEC_MIIGSK_CFGR);

                        /* re-enable the gasket */
                        writel(2, fep->hwp + FEC_MIIGSK_ENR);
                }
#endif
        }

#if !defined(CONFIG_M5272)
        /* enable pause frame*/
        if ((fep->pause_flag & FEC_PAUSE_FLAG_ENABLE) ||
            ((fep->pause_flag & FEC_PAUSE_FLAG_AUTONEG) &&
             ndev->phydev && ndev->phydev->pause)) {
                rcntl |= FEC_ENET_FCE;

                /* set FIFO threshold parameter to reduce overrun */
                writel(FEC_ENET_RSEM_V, fep->hwp + FEC_R_FIFO_RSEM);
                writel(FEC_ENET_RSFL_V, fep->hwp + FEC_R_FIFO_RSFL);
                writel(FEC_ENET_RAEM_V, fep->hwp + FEC_R_FIFO_RAEM);
                writel(FEC_ENET_RAFL_V, fep->hwp + FEC_R_FIFO_RAFL);

                /* OPD */
                writel(FEC_ENET_OPD_V, fep->hwp + FEC_OPD);
        } else {
                rcntl &= ~FEC_ENET_FCE;
        }
#endif /* !defined(CONFIG_M5272) */

        writel(rcntl, fep->hwp + FEC_R_CNTRL);

        /* Setup multicast filter. */
        set_multicast_list(ndev);
#ifndef CONFIG_M5272
        writel(0, fep->hwp + FEC_HASH_TABLE_HIGH);
        writel(0, fep->hwp + FEC_HASH_TABLE_LOW);
#endif

        if (fep->quirks & FEC_QUIRK_ENET_MAC) {
                /* enable ENET endian swap */
                ecntl |= (1 << 8);
                /* enable ENET store and forward mode */
                writel(1 << 8, fep->hwp + FEC_X_WMRK);
        }

        if (fep->bufdesc_ex)
                ecntl |= (1 << 4);

#ifndef CONFIG_M5272
        /* Enable the MIB statistic event counters */
        writel(0 << 31, fep->hwp + FEC_MIB_CTRLSTAT);
#endif

        /* And last, enable the transmit and receive processing */
        writel(ecntl, fep->hwp + FEC_ECNTRL);
        fec_enet_active_rxring(ndev);

        if (fep->bufdesc_ex)
                fec_ptp_start_cyclecounter(ndev);

        /* Enable interrupts we wish to service */
        if (fep->link)
                writel(FEC_DEFAULT_IMASK, fep->hwp + FEC_IMASK);
        else
                writel(0, fep->hwp + FEC_IMASK);

        /* Init the interrupt coalescing */
        fec_enet_itr_coal_init(ndev);

}

static void fec_enet_stop_mode(struct fec_enet_private *fep, bool enabled)
{
        struct fec_platform_data *pdata = fep->pdev->dev.platform_data;
        struct fec_stop_mode_gpr *stop_gpr = &fep->stop_gpr;

        if (stop_gpr->gpr) {
                if (enabled)
                        regmap_update_bits(stop_gpr->gpr, stop_gpr->reg,
                                           BIT(stop_gpr->bit),
                                           BIT(stop_gpr->bit));
                else
                        regmap_update_bits(stop_gpr->gpr, stop_gpr->reg,
                                           BIT(stop_gpr->bit), 0);
        } else if (pdata && pdata->sleep_mode_enable) {
                pdata->sleep_mode_enable(enabled);
        }
}

static void
fec_stop(struct net_device *ndev)
{
        struct fec_enet_private *fep = netdev_priv(ndev);
        u32 rmii_mode = readl(fep->hwp + FEC_R_CNTRL) & (1 << 8);
        u32 val;

        /* We cannot expect a graceful transmit stop without link !!! */
        if (fep->link) {
                writel(1, fep->hwp + FEC_X_CNTRL); /* Graceful transmit stop */
                udelay(10);
                if (!(readl(fep->hwp + FEC_IEVENT) & FEC_ENET_GRA))
                        netdev_err(ndev, "Graceful transmit stop did not complete!\n");
        }

        /* Whack a reset.  We should wait for this.
         * For i.MX6SX SOC, enet use AXI bus, we use disable MAC
         * instead of reset MAC itself.
         */
        if (!(fep->wol_flag & FEC_WOL_FLAG_SLEEP_ON)) {
                if (fep->quirks & FEC_QUIRK_HAS_MULTI_QUEUES) {
                        writel(0, fep->hwp + FEC_ECNTRL);
                } else {
                        writel(1, fep->hwp + FEC_ECNTRL);
                        udelay(10);
                }
                writel(FEC_DEFAULT_IMASK, fep->hwp + FEC_IMASK);
        } else {
                writel(FEC_DEFAULT_IMASK | FEC_ENET_WAKEUP, fep->hwp + FEC_IMASK);
                val = readl(fep->hwp + FEC_ECNTRL);
                val |= (FEC_ECR_MAGICEN | FEC_ECR_SLEEP);
                writel(val, fep->hwp + FEC_ECNTRL);
                fec_enet_stop_mode(fep, true);
        }
        writel(fep->phy_speed, fep->hwp + FEC_MII_SPEED);

        /* We have to keep ENET enabled to have MII interrupt stay working */
        if (fep->quirks & FEC_QUIRK_ENET_MAC &&
                !(fep->wol_flag & FEC_WOL_FLAG_SLEEP_ON)) {
                writel(2, fep->hwp + FEC_ECNTRL);
                writel(rmii_mode, fep->hwp + FEC_R_CNTRL);
        }
}


static void
fec_timeout(struct net_device *ndev, unsigned int txqueue)
{
        struct fec_enet_private *fep = netdev_priv(ndev);

        fec_dump(ndev);

        ndev->stats.tx_errors++;

        schedule_work(&fep->tx_timeout_work);
}

static void fec_enet_timeout_work(struct work_struct *work)
{
        struct fec_enet_private *fep =
                container_of(work, struct fec_enet_private, tx_timeout_work);
        struct net_device *ndev = fep->netdev;

        rtnl_lock();
        if (netif_device_present(ndev) || netif_running(ndev)) {
                napi_disable(&fep->napi);
                netif_tx_lock_bh(ndev);
                fec_restart(ndev);
                netif_tx_wake_all_queues(ndev);
                netif_tx_unlock_bh(ndev);
                napi_enable(&fep->napi);
        }
        rtnl_unlock();
}

static void
fec_enet_hwtstamp(struct fec_enet_private *fep, unsigned ts,
        struct skb_shared_hwtstamps *hwtstamps)
{
        unsigned long flags;
        u64 ns;

        spin_lock_irqsave(&fep->tmreg_lock, flags);
        ns = timecounter_cyc2time(&fep->tc, ts);
        spin_unlock_irqrestore(&fep->tmreg_lock, flags);

        memset(hwtstamps, 0, sizeof(*hwtstamps));
        hwtstamps->hwtstamp = ns_to_ktime(ns);
}

static void
fec_enet_tx_queue(struct net_device *ndev, u16 queue_id)
{
        struct  fec_enet_private *fep;
        struct bufdesc *bdp;
        unsigned short status;
        struct  sk_buff *skb;
        struct fec_enet_priv_tx_q *txq;
        struct netdev_queue *nq;
        int     index = 0;
        int     entries_free;

        fep = netdev_priv(ndev);

        txq = fep->tx_queue[queue_id];
        /* get next bdp of dirty_tx */
        nq = netdev_get_tx_queue(ndev, queue_id);
        bdp = txq->dirty_tx;

        /* get next bdp of dirty_tx */
        bdp = fec_enet_get_nextdesc(bdp, &txq->bd);

        while (bdp != READ_ONCE(txq->bd.cur)) {
                /* Order the load of bd.cur and cbd_sc */
                rmb();
                status = fec16_to_cpu(READ_ONCE(bdp->cbd_sc));
                if (status & BD_ENET_TX_READY)
                        break;

                index = fec_enet_get_bd_index(bdp, &txq->bd);

                skb = txq->tx_skbuff[index];
                txq->tx_skbuff[index] = NULL;
                if (!IS_TSO_HEADER(txq, fec32_to_cpu(bdp->cbd_bufaddr)))
                        dma_unmap_single(&fep->pdev->dev,
                                         fec32_to_cpu(bdp->cbd_bufaddr),
                                         fec16_to_cpu(bdp->cbd_datlen),
                                         DMA_TO_DEVICE);
                bdp->cbd_bufaddr = cpu_to_fec32(0);
                if (!skb)
                        goto skb_done;

                /* Check for errors. */
                if (status & (BD_ENET_TX_HB | BD_ENET_TX_LC |
                                   BD_ENET_TX_RL | BD_ENET_TX_UN |
                                   BD_ENET_TX_CSL)) {
                        ndev->stats.tx_errors++;
                        if (status & BD_ENET_TX_HB)  /* No heartbeat */
                                ndev->stats.tx_heartbeat_errors++;
                        if (status & BD_ENET_TX_LC)  /* Late collision */
                                ndev->stats.tx_window_errors++;
                        if (status & BD_ENET_TX_RL)  /* Retrans limit */
                                ndev->stats.tx_aborted_errors++;
                        if (status & BD_ENET_TX_UN)  /* Underrun */
                                ndev->stats.tx_fifo_errors++;
                        if (status & BD_ENET_TX_CSL) /* Carrier lost */
                                ndev->stats.tx_carrier_errors++;
                } else {
                        ndev->stats.tx_packets++;
                        ndev->stats.tx_bytes += skb->len;
                }

                /* NOTE: SKBTX_IN_PROGRESS being set does not imply it's we who
                 * are to time stamp the packet, so we still need to check time
                 * stamping enabled flag.
                 */
                if (unlikely(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS &&
                             fep->hwts_tx_en) &&
                    fep->bufdesc_ex) {
                        struct skb_shared_hwtstamps shhwtstamps;
                        struct bufdesc_ex *ebdp = (struct bufdesc_ex *)bdp;

                        fec_enet_hwtstamp(fep, fec32_to_cpu(ebdp->ts), &shhwtstamps);
                        skb_tstamp_tx(skb, &shhwtstamps);
                }

                /* Deferred means some collisions occurred during transmit,
                 * but we eventually sent the packet OK.
                 */
                if (status & BD_ENET_TX_DEF)
                        ndev->stats.collisions++;

                /* Free the sk buffer associated with this last transmit */
                dev_kfree_skb_any(skb);
skb_done:
                /* Make sure the update to bdp and tx_skbuff are performed
                 * before dirty_tx
                 */
                wmb();
                txq->dirty_tx = bdp;

                /* Update pointer to next buffer descriptor to be transmitted */
                bdp = fec_enet_get_nextdesc(bdp, &txq->bd);

                /* Since we have freed up a buffer, the ring is no longer full
                 */
                if (netif_tx_queue_stopped(nq)) {
                        entries_free = fec_enet_get_free_txdesc_num(txq);
                        if (entries_free >= txq->tx_wake_threshold)
                                netif_tx_wake_queue(nq);
                }
        }

        /* ERR006358: Keep the transmitter going */
        if (bdp != txq->bd.cur &&
            readl(txq->bd.reg_desc_active) == 0)
                writel(0, txq->bd.reg_desc_active);
}

static void fec_enet_tx(struct net_device *ndev)
{
        struct fec_enet_private *fep = netdev_priv(ndev);
        int i;

        /* Make sure that AVB queues are processed first. */
        for (i = fep->num_tx_queues - 1; i >= 0; i--)
                fec_enet_tx_queue(ndev, i);
}

static int
fec_enet_new_rxbdp(struct net_device *ndev, struct bufdesc *bdp, struct sk_buff *skb)
{
        struct  fec_enet_private *fep = netdev_priv(ndev);
        int off;

        off = ((unsigned long)skb->data) & fep->rx_align;
        if (off)
                skb_reserve(skb, fep->rx_align + 1 - off);

        bdp->cbd_bufaddr = cpu_to_fec32(dma_map_single(&fep->pdev->dev, skb->data, FEC_ENET_RX_FRSIZE - fep->rx_align, DMA_FROM_DEVICE));
        if (dma_mapping_error(&fep->pdev->dev, fec32_to_cpu(bdp->cbd_bufaddr))) {
                if (net_ratelimit())
                        netdev_err(ndev, "Rx DMA memory map failed\n");
                return -ENOMEM;
        }

        return 0;
}

static bool fec_enet_copybreak(struct net_device *ndev, struct sk_buff **skb,
                               struct bufdesc *bdp, u32 length, bool swap)
{
        struct  fec_enet_private *fep = netdev_priv(ndev);
        struct sk_buff *new_skb;

        if (length > fep->rx_copybreak)
                return false;

        new_skb = netdev_alloc_skb(ndev, length);
        if (!new_skb)
                return false;

        dma_sync_single_for_cpu(&fep->pdev->dev,
                                fec32_to_cpu(bdp->cbd_bufaddr),
                                FEC_ENET_RX_FRSIZE - fep->rx_align,
                                DMA_FROM_DEVICE);
        if (!swap)
                memcpy(new_skb->data, (*skb)->data, length);
        else
                swap_buffer2(new_skb->data, (*skb)->data, length);
        *skb = new_skb;

        return true;
}

/* During a receive, the bd_rx.cur points to the current incoming buffer.
 * When we update through the ring, if the next incoming buffer has
 * not been given to the system, we just set the empty indicator,
 * effectively tossing the packet.
 */
static int
fec_enet_rx_queue(struct net_device *ndev, int budget, u16 queue_id)
{
        struct fec_enet_private *fep = netdev_priv(ndev);
        struct fec_enet_priv_rx_q *rxq;
        struct bufdesc *bdp;
        unsigned short status;
        struct  sk_buff *skb_new = NULL;
        struct  sk_buff *skb;
        ushort  pkt_len;
        __u8 *data;
        int     pkt_received = 0;
        struct  bufdesc_ex *ebdp = NULL;
        bool    vlan_packet_rcvd = false;
        u16     vlan_tag;
        int     index = 0;
        bool    is_copybreak;
        bool    need_swap = fep->quirks & FEC_QUIRK_SWAP_FRAME;

#ifdef CONFIG_M532x
        flush_cache_all();
#endif
        rxq = fep->rx_queue[queue_id];

        /* First, grab all of the stats for the incoming packet.
         * These get messed up if we get called due to a busy condition.
         */
        bdp = rxq->bd.cur;

        while (!((status = fec16_to_cpu(bdp->cbd_sc)) & BD_ENET_RX_EMPTY)) {

                if (pkt_received >= budget)
                        break;
                pkt_received++;

                writel(FEC_ENET_RXF, fep->hwp + FEC_IEVENT);

                /* Check for errors. */
                status ^= BD_ENET_RX_LAST;
                if (status & (BD_ENET_RX_LG | BD_ENET_RX_SH | BD_ENET_RX_NO |
                           BD_ENET_RX_CR | BD_ENET_RX_OV | BD_ENET_RX_LAST |
                           BD_ENET_RX_CL)) {
                        ndev->stats.rx_errors++;
                        if (status & BD_ENET_RX_OV) {
                                /* FIFO overrun */
                                ndev->stats.rx_fifo_errors++;
                                goto rx_processing_done;
                        }
                        if (status & (BD_ENET_RX_LG | BD_ENET_RX_SH
                                                | BD_ENET_RX_LAST)) {
                                /* Frame too long or too short. */
                                ndev->stats.rx_length_errors++;
                                if (status & BD_ENET_RX_LAST)
                                        netdev_err(ndev, "rcv is not +last\n");
                        }
                        if (status & BD_ENET_RX_CR)     /* CRC Error */
                                ndev->stats.rx_crc_errors++;
                        /* Report late collisions as a frame error. */
                        if (status & (BD_ENET_RX_NO | BD_ENET_RX_CL))
                                ndev->stats.rx_frame_errors++;
                        goto rx_processing_done;
                }

                /* Process the incoming frame. */
                ndev->stats.rx_packets++;
                pkt_len = fec16_to_cpu(bdp->cbd_datlen);
                ndev->stats.rx_bytes += pkt_len;

                index = fec_enet_get_bd_index(bdp, &rxq->bd);
                skb = rxq->rx_skbuff[index];

                /* The packet length includes FCS, but we don't want to
                 * include that when passing upstream as it messes up
                 * bridging applications.
                 */
                is_copybreak = fec_enet_copybreak(ndev, &skb, bdp, pkt_len - 4,
                                                  need_swap);
                if (!is_copybreak) {
                        skb_new = netdev_alloc_skb(ndev, FEC_ENET_RX_FRSIZE);
                        if (unlikely(!skb_new)) {
                                ndev->stats.rx_dropped++;
                                goto rx_processing_done;
                        }
                        dma_unmap_single(&fep->pdev->dev,
                                         fec32_to_cpu(bdp->cbd_bufaddr),
                                         FEC_ENET_RX_FRSIZE - fep->rx_align,
                                         DMA_FROM_DEVICE);
                }

                prefetch(skb->data - NET_IP_ALIGN);
                skb_put(skb, pkt_len - 4);
                data = skb->data;

                if (!is_copybreak && need_swap)
                        swap_buffer(data, pkt_len);

#if !defined(CONFIG_M5272)
                if (fep->quirks & FEC_QUIRK_HAS_RACC)
                        data = skb_pull_inline(skb, 2);
#endif

                /* Extract the enhanced buffer descriptor */
                ebdp = NULL;
                if (fep->bufdesc_ex)
                        ebdp = (struct bufdesc_ex *)bdp;

                /* If this is a VLAN packet remove the VLAN Tag */
                vlan_packet_rcvd = false;
                if ((ndev->features & NETIF_F_HW_VLAN_CTAG_RX) &&
                    fep->bufdesc_ex &&
                    (ebdp->cbd_esc & cpu_to_fec32(BD_ENET_RX_VLAN))) {
                        /* Push and remove the vlan tag */
                        struct vlan_hdr *vlan_header =
                                        (struct vlan_hdr *) (data + ETH_HLEN);
                        vlan_tag = ntohs(vlan_header->h_vlan_TCI);

                        vlan_packet_rcvd = true;

                        memmove(skb->data + VLAN_HLEN, data, ETH_ALEN * 2);
                        skb_pull(skb, VLAN_HLEN);
                }

                skb->protocol = eth_type_trans(skb, ndev);

                /* Get receive timestamp from the skb */
                if (fep->hwts_rx_en && fep->bufdesc_ex)
                        fec_enet_hwtstamp(fep, fec32_to_cpu(ebdp->ts),
                                          skb_hwtstamps(skb));

                if (fep->bufdesc_ex &&
                    (fep->csum_flags & FLAG_RX_CSUM_ENABLED)) {
                        if (!(ebdp->cbd_esc & cpu_to_fec32(FLAG_RX_CSUM_ERROR))) {
                                /* don't check it */
                                skb->ip_summed = CHECKSUM_UNNECESSARY;
                        } else {
                                skb_checksum_none_assert(skb);
                        }
                }

                /* Handle received VLAN packets */
                if (vlan_packet_rcvd)
                        __vlan_hwaccel_put_tag(skb,
                                               htons(ETH_P_8021Q),
                                               vlan_tag);

                skb_record_rx_queue(skb, queue_id);
                napi_gro_receive(&fep->napi, skb);

                if (is_copybreak) {
                        dma_sync_single_for_device(&fep->pdev->dev,
                                                   fec32_to_cpu(bdp->cbd_bufaddr),
                                                   FEC_ENET_RX_FRSIZE - fep->rx_align,
                                                   DMA_FROM_DEVICE);
                } else {
                        rxq->rx_skbuff[index] = skb_new;
                        fec_enet_new_rxbdp(ndev, bdp, skb_new);
                }

rx_processing_done:
                /* Clear the status flags for this buffer */
                status &= ~BD_ENET_RX_STATS;

                /* Mark the buffer empty */
                status |= BD_ENET_RX_EMPTY;

                if (fep->bufdesc_ex) {
                        struct bufdesc_ex *ebdp = (struct bufdesc_ex *)bdp;

                        ebdp->cbd_esc = cpu_to_fec32(BD_ENET_RX_INT);
                        ebdp->cbd_prot = 0;
                        ebdp->cbd_bdu = 0;
                }
                /* Make sure the updates to rest of the descriptor are
                 * performed before transferring ownership.
                 */
                wmb();
                bdp->cbd_sc = cpu_to_fec16(status);

                /* Update BD pointer to next entry */
                bdp = fec_enet_get_nextdesc(bdp, &rxq->bd);

                /* Doing this here will keep the FEC running while we process
                 * incoming frames.  On a heavily loaded network, we should be
                 * able to keep up at the expense of system resources.
                 */
                writel(0, rxq->bd.reg_desc_active);
        }
        rxq->bd.cur = bdp;
        return pkt_received;
}

static int fec_enet_rx(struct net_device *ndev, int budget)
{
        struct fec_enet_private *fep = netdev_priv(ndev);
        int i, done = 0;

        /* Make sure that AVB queues are processed first. */
        for (i = fep->num_rx_queues - 1; i >= 0; i--)
                done += fec_enet_rx_queue(ndev, budget - done, i);

        return done;
}

static bool fec_enet_collect_events(struct fec_enet_private *fep)
{
        uint int_events;

        int_events = readl(fep->hwp + FEC_IEVENT);

        /* Don't clear MDIO events, we poll for those */
        int_events &= ~FEC_ENET_MII;

        writel(int_events, fep->hwp + FEC_IEVENT);

        return int_events != 0;
}

static irqreturn_t
fec_enet_interrupt(int irq, void *dev_id)
{
        struct net_device *ndev = dev_id;
        struct fec_enet_private *fep = netdev_priv(ndev);
        irqreturn_t ret = IRQ_NONE;

        if (fec_enet_collect_events(fep) && fep->link) {
                ret = IRQ_HANDLED;

                if (napi_schedule_prep(&fep->napi)) {
                        /* Disable interrupts */
                        writel(0, fep->hwp + FEC_IMASK);
                        __napi_schedule(&fep->napi);
                }
        }

        return ret;
}

static int fec_enet_rx_napi(struct napi_struct *napi, int budget)
{
        struct net_device *ndev = napi->dev;
        struct fec_enet_private *fep = netdev_priv(ndev);
        int done = 0;

        do {
                done += fec_enet_rx(ndev, budget - done);
                fec_enet_tx(ndev);
        } while ((done < budget) && fec_enet_collect_events(fep));

        if (done < budget) {
                napi_complete_done(napi, done);
                writel(FEC_DEFAULT_IMASK, fep->hwp + FEC_IMASK);
        }

        return done;
}

/* ------------------------------------------------------------------------- */
static int fec_get_mac(struct net_device *ndev)
{
        struct fec_enet_private *fep = netdev_priv(ndev);
        unsigned char *iap, tmpaddr[ETH_ALEN];
        int ret;

        /*
         * try to get mac address in following order:
         *
         * 1) module parameter via kernel command line in form
         *    fec.macaddr=0x00,0x04,0x9f,0x01,0x30,0xe0
         */
        iap = macaddr;

        /*
         * 2) from device tree data
         */
        if (!is_valid_ether_addr(iap)) {
                struct device_node *np = fep->pdev->dev.of_node;
                if (np) {
                        ret = of_get_mac_address(np, tmpaddr);
                        if (!ret)
                                iap = tmpaddr;
                        else if (ret == -EPROBE_DEFER)
                                return ret;
                }
        }

        /*
         * 3) from flash or fuse (via platform data)
         */
        if (!is_valid_ether_addr(iap)) {
#ifdef CONFIG_M5272
                if (FEC_FLASHMAC)
                        iap = (unsigned char *)FEC_FLASHMAC;
#else
                struct fec_platform_data *pdata = dev_get_platdata(&fep->pdev->dev);

                if (pdata)
                        iap = (unsigned char *)&pdata->mac;
#endif
        }

        /*
         * 4) FEC mac registers set by bootloader
         */
        if (!is_valid_ether_addr(iap)) {
                *((__be32 *) &tmpaddr[0]) =
                        cpu_to_be32(readl(fep->hwp + FEC_ADDR_LOW));
                *((__be16 *) &tmpaddr[4]) =
                        cpu_to_be16(readl(fep->hwp + FEC_ADDR_HIGH) >> 16);
                iap = &tmpaddr[0];
        }

        /*
         * 5) random mac address
         */
        if (!is_valid_ether_addr(iap)) {
                /* Report it and use a random ethernet address instead */
                dev_err(&fep->pdev->dev, "Invalid MAC address: %pM\n", iap);
                eth_hw_addr_random(ndev);
                dev_info(&fep->pdev->dev, "Using random MAC address: %pM\n",
                         ndev->dev_addr);
                return 0;
        }

        memcpy(ndev->dev_addr, iap, ETH_ALEN);

        /* Adjust MAC if using macaddr */
        if (iap == macaddr)
                 ndev->dev_addr[ETH_ALEN-1] = macaddr[ETH_ALEN-1] + fep->dev_id;

        return 0;
}

/* ------------------------------------------------------------------------- */

/*
 * Phy section
 */
static void fec_enet_adjust_link(struct net_device *ndev)
{
        struct fec_enet_private *fep = netdev_priv(ndev);
        struct phy_device *phy_dev = ndev->phydev;
        int status_change = 0;

        /*
         * If the netdev is down, or is going down, we're not interested
         * in link state events, so just mark our idea of the link as down
         * and ignore the event.
         */
        if (!netif_running(ndev) || !netif_device_present(ndev)) {
                fep->link = 0;
        } else if (phy_dev->link) {
                if (!fep->link) {
                        fep->link = phy_dev->link;
                        status_change = 1;
                }

                if (fep->full_duplex != phy_dev->duplex) {
                        fep->full_duplex = phy_dev->duplex;
                        status_change = 1;
                }

                if (phy_dev->speed != fep->speed) {
                        fep->speed = phy_dev->speed;
                        status_change = 1;
                }

                /* if any of the above changed restart the FEC */
                if (status_change) {
                        napi_disable(&fep->napi);
                        netif_tx_lock_bh(ndev);
                        fec_restart(ndev);
                        netif_tx_wake_all_queues(ndev);
                        netif_tx_unlock_bh(ndev);
                        napi_enable(&fep->napi);
                }
        } else {
                if (fep->link) {
                        napi_disable(&fep->napi);
                        netif_tx_lock_bh(ndev);
                        fec_stop(ndev);
                        netif_tx_unlock_bh(ndev);
                        napi_enable(&fep->napi);
                        fep->link = phy_dev->link;
                        status_change = 1;
                }
        }

        if (status_change)
                phy_print_status(phy_dev);
}

static int fec_enet_mdio_wait(struct fec_enet_private *fep)
{
        uint ievent;
        int ret;

        ret = readl_poll_timeout_atomic(fep->hwp + FEC_IEVENT, ievent,
                                        ievent & FEC_ENET_MII, 2, 30000);

        if (!ret)
                writel(FEC_ENET_MII, fep->hwp + FEC_IEVENT);

        return ret;
}

static int fec_enet_mdio_read(struct mii_bus *bus, int mii_id, int regnum)
{
        struct fec_enet_private *fep = bus->priv;
        struct device *dev = &fep->pdev->dev;
        int ret = 0, frame_start, frame_addr, frame_op;
        bool is_c45 = !!(regnum & MII_ADDR_C45);

        ret = pm_runtime_resume_and_get(dev);
        if (ret < 0)
                return ret;

        if (is_c45) {
                frame_start = FEC_MMFR_ST_C45;

                /* write address */
                frame_addr = (regnum >> 16);
                writel(frame_start | FEC_MMFR_OP_ADDR_WRITE |
                       FEC_MMFR_PA(mii_id) | FEC_MMFR_RA(frame_addr) |
                       FEC_MMFR_TA | (regnum & 0xFFFF),
                       fep->hwp + FEC_MII_DATA);

                /* wait for end of transfer */
                ret = fec_enet_mdio_wait(fep);
                if (ret) {
                        netdev_err(fep->netdev, "MDIO address write timeout\n");
                        goto out;
                }

                frame_op = FEC_MMFR_OP_READ_C45;

        } else {
                /* C22 read */
                frame_op = FEC_MMFR_OP_READ;
                frame_start = FEC_MMFR_ST;
                frame_addr = regnum;
        }

        /* start a read op */
        writel(frame_start | frame_op |
                FEC_MMFR_PA(mii_id) | FEC_MMFR_RA(frame_addr) |
                FEC_MMFR_TA, fep->hwp + FEC_MII_DATA);

        /* wait for end of transfer */
        ret = fec_enet_mdio_wait(fep);
        if (ret) {
                netdev_err(fep->netdev, "MDIO read timeout\n");
                goto out;
        }

        ret = FEC_MMFR_DATA(readl(fep->hwp + FEC_MII_DATA));

out:
        pm_runtime_mark_last_busy(dev);
        pm_runtime_put_autosuspend(dev);

        return ret;
}

static int fec_enet_mdio_write(struct mii_bus *bus, int mii_id, int regnum,
                           u16 value)
{
        struct fec_enet_private *fep = bus->priv;
        struct device *dev = &fep->pdev->dev;
        int ret, frame_start, frame_addr;
        bool is_c45 = !!(regnum & MII_ADDR_C45);

        ret = pm_runtime_resume_and_get(dev);
        if (ret < 0)
                return ret;

        if (is_c45) {
                frame_start = FEC_MMFR_ST_C45;

                /* write address */
                frame_addr = (regnum >> 16);
                writel(frame_start | FEC_MMFR_OP_ADDR_WRITE |
                       FEC_MMFR_PA(mii_id) | FEC_MMFR_RA(frame_addr) |
                       FEC_MMFR_TA | (regnum & 0xFFFF),
                       fep->hwp + FEC_MII_DATA);

                /* wait for end of transfer */
                ret = fec_enet_mdio_wait(fep);
                if (ret) {
                        netdev_err(fep->netdev, "MDIO address write timeout\n");
                        goto out;
                }
        } else {
                /* C22 write */
                frame_start = FEC_MMFR_ST;
                frame_addr = regnum;
        }

        /* start a write op */
        writel(frame_start | FEC_MMFR_OP_WRITE |
                FEC_MMFR_PA(mii_id) | FEC_MMFR_RA(frame_addr) |
                FEC_MMFR_TA | FEC_MMFR_DATA(value),
                fep->hwp + FEC_MII_DATA);

        /* wait for end of transfer */
        ret = fec_enet_mdio_wait(fep);
        if (ret)
                netdev_err(fep->netdev, "MDIO write timeout\n");

out:
        pm_runtime_mark_last_busy(dev);
        pm_runtime_put_autosuspend(dev);

        return ret;
}

static void fec_enet_phy_reset_after_clk_enable(struct net_device *ndev)
{
        struct fec_enet_private *fep = netdev_priv(ndev);
        struct phy_device *phy_dev = ndev->phydev;

        if (phy_dev) {
                phy_reset_after_clk_enable(phy_dev);
        } else if (fep->phy_node) {
                /*
                 * If the PHY still is not bound to the MAC, but there is
                 * OF PHY node and a matching PHY device instance already,
                 * use the OF PHY node to obtain the PHY device instance,
                 * and then use that PHY device instance when triggering
                 * the PHY reset.
                 */
                phy_dev = of_phy_find_device(fep->phy_node);
                phy_reset_after_clk_enable(phy_dev);
                put_device(&phy_dev->mdio.dev);
        }
}

static int fec_enet_clk_enable(struct net_device *ndev, bool enable)
{
        struct fec_enet_private *fep = netdev_priv(ndev);
        int ret;

        if (enable) {
                ret = clk_prepare_enable(fep->clk_enet_out);
                if (ret)
                        return ret;

                if (fep->clk_ptp) {
                        mutex_lock(&fep->ptp_clk_mutex);
                        ret = clk_prepare_enable(fep->clk_ptp);
                        if (ret) {
                                mutex_unlock(&fep->ptp_clk_mutex);
                                goto failed_clk_ptp;
                        } else {
                                fep->ptp_clk_on = true;
                        }
                        mutex_unlock(&fep->ptp_clk_mutex);
                }

                ret = clk_prepare_enable(fep->clk_ref);
                if (ret)
                        goto failed_clk_ref;

                fec_enet_phy_reset_after_clk_enable(ndev);
        } else {
                clk_disable_unprepare(fep->clk_enet_out);
                if (fep->clk_ptp) {
                        mutex_lock(&fep->ptp_clk_mutex);
                        clk_disable_unprepare(fep->clk_ptp);
                        fep->ptp_clk_on = false;
                        mutex_unlock(&fep->ptp_clk_mutex);
                }
                clk_disable_unprepare(fep->clk_ref);
        }

        return 0;

failed_clk_ref:
        if (fep->clk_ptp) {
                mutex_lock(&fep->ptp_clk_mutex);
                clk_disable_unprepare(fep->clk_ptp);
                fep->ptp_clk_on = false;
                mutex_unlock(&fep->ptp_clk_mutex);
        }
failed_clk_ptp:
        clk_disable_unprepare(fep->clk_enet_out);

        return ret;
}

static int fec_enet_mii_probe(struct net_device *ndev)