net: stmmac: Implement RSS and enable it in XGMAC core

[linux.git] / drivers / net / ethernet / stmicro / stmmac / stmmac_main.c

// SPDX-License-Identifier: GPL-2.0-only
/*******************************************************************************
  This is the driver for the ST MAC 10/100/1000 on-chip Ethernet controllers.
  ST Ethernet IPs are built around a Synopsys IP Core.

        Copyright(C) 2007-2011 STMicroelectronics Ltd


  Author: Giuseppe Cavallaro <peppe.cavallaro@st.com>

  Documentation available at:
        http://www.stlinux.com
  Support available at:
        https://bugzilla.stlinux.com/
*******************************************************************************/

#include <linux/clk.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/ip.h>
#include <linux/tcp.h>
#include <linux/skbuff.h>
#include <linux/ethtool.h>
#include <linux/if_ether.h>
#include <linux/crc32.h>
#include <linux/mii.h>
#include <linux/if.h>
#include <linux/if_vlan.h>
#include <linux/dma-mapping.h>
#include <linux/slab.h>
#include <linux/prefetch.h>
#include <linux/pinctrl/consumer.h>
#ifdef CONFIG_DEBUG_FS
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#endif /* CONFIG_DEBUG_FS */
#include <linux/net_tstamp.h>
#include <linux/phylink.h>
#include <net/pkt_cls.h>
#include "stmmac_ptp.h"
#include "stmmac.h"
#include <linux/reset.h>
#include <linux/of_mdio.h>
#include "dwmac1000.h"
#include "dwxgmac2.h"
#include "hwif.h"

#define STMMAC_ALIGN(x)         __ALIGN_KERNEL(x, SMP_CACHE_BYTES)
#define TSO_MAX_BUFF_SIZE       (SZ_16K - 1)

/* Module parameters */
#define TX_TIMEO        5000
static int watchdog = TX_TIMEO;
module_param(watchdog, int, 0644);
MODULE_PARM_DESC(watchdog, "Transmit timeout in milliseconds (default 5s)");

static int debug = -1;
module_param(debug, int, 0644);
MODULE_PARM_DESC(debug, "Message Level (-1: default, 0: no output, 16: all)");

static int phyaddr = -1;
module_param(phyaddr, int, 0444);
MODULE_PARM_DESC(phyaddr, "Physical device address");

#define STMMAC_TX_THRESH        (DMA_TX_SIZE / 4)
#define STMMAC_RX_THRESH        (DMA_RX_SIZE / 4)

static int flow_ctrl = FLOW_AUTO;
module_param(flow_ctrl, int, 0644);
MODULE_PARM_DESC(flow_ctrl, "Flow control ability [on/off]");

static int pause = PAUSE_TIME;
module_param(pause, int, 0644);
MODULE_PARM_DESC(pause, "Flow Control Pause Time");

#define TC_DEFAULT 64
static int tc = TC_DEFAULT;
module_param(tc, int, 0644);
MODULE_PARM_DESC(tc, "DMA threshold control value");

#define DEFAULT_BUFSIZE 1536
static int buf_sz = DEFAULT_BUFSIZE;
module_param(buf_sz, int, 0644);
MODULE_PARM_DESC(buf_sz, "DMA buffer size");

#define STMMAC_RX_COPYBREAK     256

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

#define STMMAC_DEFAULT_LPI_TIMER        1000
static int eee_timer = STMMAC_DEFAULT_LPI_TIMER;
module_param(eee_timer, int, 0644);
MODULE_PARM_DESC(eee_timer, "LPI tx expiration time in msec");
#define STMMAC_LPI_T(x) (jiffies + msecs_to_jiffies(x))

/* By default the driver will use the ring mode to manage tx and rx descriptors,
 * but allow user to force to use the chain instead of the ring
 */
static unsigned int chain_mode;
module_param(chain_mode, int, 0444);
MODULE_PARM_DESC(chain_mode, "To use chain instead of ring mode");

static irqreturn_t stmmac_interrupt(int irq, void *dev_id);

#ifdef CONFIG_DEBUG_FS
static int stmmac_init_fs(struct net_device *dev);
static void stmmac_exit_fs(struct net_device *dev);
#endif

#define STMMAC_COAL_TIMER(x) (jiffies + usecs_to_jiffies(x))

/**
 * stmmac_verify_args - verify the driver parameters.
 * Description: it checks the driver parameters and set a default in case of
 * errors.
 */
static void stmmac_verify_args(void)
{
        if (unlikely(watchdog < 0))
                watchdog = TX_TIMEO;
        if (unlikely((buf_sz < DEFAULT_BUFSIZE) || (buf_sz > BUF_SIZE_16KiB)))
                buf_sz = DEFAULT_BUFSIZE;
        if (unlikely(flow_ctrl > 1))
                flow_ctrl = FLOW_AUTO;
        else if (likely(flow_ctrl < 0))
                flow_ctrl = FLOW_OFF;
        if (unlikely((pause < 0) || (pause > 0xffff)))
                pause = PAUSE_TIME;
        if (eee_timer < 0)
                eee_timer = STMMAC_DEFAULT_LPI_TIMER;
}

/**
 * stmmac_disable_all_queues - Disable all queues
 * @priv: driver private structure
 */
static void stmmac_disable_all_queues(struct stmmac_priv *priv)
{
        u32 rx_queues_cnt = priv->plat->rx_queues_to_use;
        u32 tx_queues_cnt = priv->plat->tx_queues_to_use;
        u32 maxq = max(rx_queues_cnt, tx_queues_cnt);
        u32 queue;

        for (queue = 0; queue < maxq; queue++) {
                struct stmmac_channel *ch = &priv->channel[queue];

                if (queue < rx_queues_cnt)
                        napi_disable(&ch->rx_napi);
                if (queue < tx_queues_cnt)
                        napi_disable(&ch->tx_napi);
        }
}

/**
 * stmmac_enable_all_queues - Enable all queues
 * @priv: driver private structure
 */
static void stmmac_enable_all_queues(struct stmmac_priv *priv)
{
        u32 rx_queues_cnt = priv->plat->rx_queues_to_use;
        u32 tx_queues_cnt = priv->plat->tx_queues_to_use;
        u32 maxq = max(rx_queues_cnt, tx_queues_cnt);
        u32 queue;

        for (queue = 0; queue < maxq; queue++) {
                struct stmmac_channel *ch = &priv->channel[queue];

                if (queue < rx_queues_cnt)
                        napi_enable(&ch->rx_napi);
                if (queue < tx_queues_cnt)
                        napi_enable(&ch->tx_napi);
        }
}

/**
 * stmmac_stop_all_queues - Stop all queues
 * @priv: driver private structure
 */
static void stmmac_stop_all_queues(struct stmmac_priv *priv)
{
        u32 tx_queues_cnt = priv->plat->tx_queues_to_use;
        u32 queue;

        for (queue = 0; queue < tx_queues_cnt; queue++)
                netif_tx_stop_queue(netdev_get_tx_queue(priv->dev, queue));
}

/**
 * stmmac_start_all_queues - Start all queues
 * @priv: driver private structure
 */
static void stmmac_start_all_queues(struct stmmac_priv *priv)
{
        u32 tx_queues_cnt = priv->plat->tx_queues_to_use;
        u32 queue;

        for (queue = 0; queue < tx_queues_cnt; queue++)
                netif_tx_start_queue(netdev_get_tx_queue(priv->dev, queue));
}

static void stmmac_service_event_schedule(struct stmmac_priv *priv)
{
        if (!test_bit(STMMAC_DOWN, &priv->state) &&
            !test_and_set_bit(STMMAC_SERVICE_SCHED, &priv->state))
                queue_work(priv->wq, &priv->service_task);
}

static void stmmac_global_err(struct stmmac_priv *priv)
{
        netif_carrier_off(priv->dev);
        set_bit(STMMAC_RESET_REQUESTED, &priv->state);
        stmmac_service_event_schedule(priv);
}

/**
 * stmmac_clk_csr_set - dynamically set the MDC clock
 * @priv: driver private structure
 * Description: this is to dynamically set the MDC clock according to the csr
 * clock input.
 * Note:
 *      If a specific clk_csr value is passed from the platform
 *      this means that the CSR Clock Range selection cannot be
 *      changed at run-time and it is fixed (as reported in the driver
 *      documentation). Viceversa the driver will try to set the MDC
 *      clock dynamically according to the actual clock input.
 */
static void stmmac_clk_csr_set(struct stmmac_priv *priv)
{
        u32 clk_rate;

        clk_rate = clk_get_rate(priv->plat->stmmac_clk);

        /* Platform provided default clk_csr would be assumed valid
         * for all other cases except for the below mentioned ones.
         * For values higher than the IEEE 802.3 specified frequency
         * we can not estimate the proper divider as it is not known
         * the frequency of clk_csr_i. So we do not change the default
         * divider.
         */
        if (!(priv->clk_csr & MAC_CSR_H_FRQ_MASK)) {
                if (clk_rate < CSR_F_35M)
                        priv->clk_csr = STMMAC_CSR_20_35M;
                else if ((clk_rate >= CSR_F_35M) && (clk_rate < CSR_F_60M))
                        priv->clk_csr = STMMAC_CSR_35_60M;
                else if ((clk_rate >= CSR_F_60M) && (clk_rate < CSR_F_100M))
                        priv->clk_csr = STMMAC_CSR_60_100M;
                else if ((clk_rate >= CSR_F_100M) && (clk_rate < CSR_F_150M))
                        priv->clk_csr = STMMAC_CSR_100_150M;
                else if ((clk_rate >= CSR_F_150M) && (clk_rate < CSR_F_250M))
                        priv->clk_csr = STMMAC_CSR_150_250M;
                else if ((clk_rate >= CSR_F_250M) && (clk_rate < CSR_F_300M))
                        priv->clk_csr = STMMAC_CSR_250_300M;
        }

        if (priv->plat->has_sun8i) {
                if (clk_rate > 160000000)
                        priv->clk_csr = 0x03;
                else if (clk_rate > 80000000)
                        priv->clk_csr = 0x02;
                else if (clk_rate > 40000000)
                        priv->clk_csr = 0x01;
                else
                        priv->clk_csr = 0;
        }

        if (priv->plat->has_xgmac) {
                if (clk_rate > 400000000)
                        priv->clk_csr = 0x5;
                else if (clk_rate > 350000000)
                        priv->clk_csr = 0x4;
                else if (clk_rate > 300000000)
                        priv->clk_csr = 0x3;
                else if (clk_rate > 250000000)
                        priv->clk_csr = 0x2;
                else if (clk_rate > 150000000)
                        priv->clk_csr = 0x1;
                else
                        priv->clk_csr = 0x0;
        }
}

static void print_pkt(unsigned char *buf, int len)
{
        pr_debug("len = %d byte, buf addr: 0x%p\n", len, buf);
        print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, buf, len);
}

static inline u32 stmmac_tx_avail(struct stmmac_priv *priv, u32 queue)
{
        struct stmmac_tx_queue *tx_q = &priv->tx_queue[queue];
        u32 avail;

        if (tx_q->dirty_tx > tx_q->cur_tx)
                avail = tx_q->dirty_tx - tx_q->cur_tx - 1;
        else
                avail = DMA_TX_SIZE - tx_q->cur_tx + tx_q->dirty_tx - 1;

        return avail;
}

/**
 * stmmac_rx_dirty - Get RX queue dirty
 * @priv: driver private structure
 * @queue: RX queue index
 */
static inline u32 stmmac_rx_dirty(struct stmmac_priv *priv, u32 queue)
{
        struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];
        u32 dirty;

        if (rx_q->dirty_rx <= rx_q->cur_rx)
                dirty = rx_q->cur_rx - rx_q->dirty_rx;
        else
                dirty = DMA_RX_SIZE - rx_q->dirty_rx + rx_q->cur_rx;

        return dirty;
}

/**
 * stmmac_enable_eee_mode - check and enter in LPI mode
 * @priv: driver private structure
 * Description: this function is to verify and enter in LPI mode in case of
 * EEE.
 */
static void stmmac_enable_eee_mode(struct stmmac_priv *priv)
{
        u32 tx_cnt = priv->plat->tx_queues_to_use;
        u32 queue;

        /* check if all TX queues have the work finished */
        for (queue = 0; queue < tx_cnt; queue++) {
                struct stmmac_tx_queue *tx_q = &priv->tx_queue[queue];

                if (tx_q->dirty_tx != tx_q->cur_tx)
                        return; /* still unfinished work */
        }

        /* Check and enter in LPI mode */
        if (!priv->tx_path_in_lpi_mode)
                stmmac_set_eee_mode(priv, priv->hw,
                                priv->plat->en_tx_lpi_clockgating);
}

/**
 * stmmac_disable_eee_mode - disable and exit from LPI mode
 * @priv: driver private structure
 * Description: this function is to exit and disable EEE in case of
 * LPI state is true. This is called by the xmit.
 */
void stmmac_disable_eee_mode(struct stmmac_priv *priv)
{
        stmmac_reset_eee_mode(priv, priv->hw);
        del_timer_sync(&priv->eee_ctrl_timer);
        priv->tx_path_in_lpi_mode = false;
}

/**
 * stmmac_eee_ctrl_timer - EEE TX SW timer.
 * @arg : data hook
 * Description:
 *  if there is no data transfer and if we are not in LPI state,
 *  then MAC Transmitter can be moved to LPI state.
 */
static void stmmac_eee_ctrl_timer(struct timer_list *t)
{
        struct stmmac_priv *priv = from_timer(priv, t, eee_ctrl_timer);

        stmmac_enable_eee_mode(priv);
        mod_timer(&priv->eee_ctrl_timer, STMMAC_LPI_T(eee_timer));
}

/**
 * stmmac_eee_init - init EEE
 * @priv: driver private structure
 * Description:
 *  if the GMAC supports the EEE (from the HW cap reg) and the phy device
 *  can also manage EEE, this function enable the LPI state and start related
 *  timer.
 */
bool stmmac_eee_init(struct stmmac_priv *priv)
{
        int tx_lpi_timer = priv->tx_lpi_timer;

        /* Using PCS we cannot dial with the phy registers at this stage
         * so we do not support extra feature like EEE.
         */
        if ((priv->hw->pcs == STMMAC_PCS_RGMII) ||
            (priv->hw->pcs == STMMAC_PCS_TBI) ||
            (priv->hw->pcs == STMMAC_PCS_RTBI))
                return false;

        /* Check if MAC core supports the EEE feature. */
        if (!priv->dma_cap.eee)
                return false;

        mutex_lock(&priv->lock);

        /* Check if it needs to be deactivated */
        if (!priv->eee_active) {
                if (priv->eee_enabled) {
                        netdev_dbg(priv->dev, "disable EEE\n");
                        del_timer_sync(&priv->eee_ctrl_timer);
                        stmmac_set_eee_timer(priv, priv->hw, 0, tx_lpi_timer);
                }
                mutex_unlock(&priv->lock);
                return false;
        }

        if (priv->eee_active && !priv->eee_enabled) {
                timer_setup(&priv->eee_ctrl_timer, stmmac_eee_ctrl_timer, 0);
                mod_timer(&priv->eee_ctrl_timer, STMMAC_LPI_T(eee_timer));
                stmmac_set_eee_timer(priv, priv->hw, STMMAC_DEFAULT_LIT_LS,
                                     tx_lpi_timer);
        }

        mutex_unlock(&priv->lock);
        netdev_dbg(priv->dev, "Energy-Efficient Ethernet initialized\n");
        return true;
}

/* stmmac_get_tx_hwtstamp - get HW TX timestamps
 * @priv: driver private structure
 * @p : descriptor pointer
 * @skb : the socket buffer
 * Description :
 * This function will read timestamp from the descriptor & pass it to stack.
 * and also perform some sanity checks.
 */
static void stmmac_get_tx_hwtstamp(struct stmmac_priv *priv,
                                   struct dma_desc *p, struct sk_buff *skb)
{
        struct skb_shared_hwtstamps shhwtstamp;
        u64 ns = 0;

        if (!priv->hwts_tx_en)
                return;

        /* exit if skb doesn't support hw tstamp */
        if (likely(!skb || !(skb_shinfo(skb)->tx_flags & SKBTX_IN_PROGRESS)))
                return;

        /* check tx tstamp status */
        if (stmmac_get_tx_timestamp_status(priv, p)) {
                /* get the valid tstamp */
                stmmac_get_timestamp(priv, p, priv->adv_ts, &ns);

                memset(&shhwtstamp, 0, sizeof(struct skb_shared_hwtstamps));
                shhwtstamp.hwtstamp = ns_to_ktime(ns);

                netdev_dbg(priv->dev, "get valid TX hw timestamp %llu\n", ns);
                /* pass tstamp to stack */
                skb_tstamp_tx(skb, &shhwtstamp);
        }

        return;
}

/* stmmac_get_rx_hwtstamp - get HW RX timestamps
 * @priv: driver private structure
 * @p : descriptor pointer
 * @np : next descriptor pointer
 * @skb : the socket buffer
 * Description :
 * This function will read received packet's timestamp from the descriptor
 * and pass it to stack. It also perform some sanity checks.
 */
static void stmmac_get_rx_hwtstamp(struct stmmac_priv *priv, struct dma_desc *p,
                                   struct dma_desc *np, struct sk_buff *skb)
{
        struct skb_shared_hwtstamps *shhwtstamp = NULL;
        struct dma_desc *desc = p;
        u64 ns = 0;

        if (!priv->hwts_rx_en)
                return;
        /* For GMAC4, the valid timestamp is from CTX next desc. */
        if (priv->plat->has_gmac4 || priv->plat->has_xgmac)
                desc = np;

        /* Check if timestamp is available */
        if (stmmac_get_rx_timestamp_status(priv, p, np, priv->adv_ts)) {
                stmmac_get_timestamp(priv, desc, priv->adv_ts, &ns);
                netdev_dbg(priv->dev, "get valid RX hw timestamp %llu\n", ns);
                shhwtstamp = skb_hwtstamps(skb);
                memset(shhwtstamp, 0, sizeof(struct skb_shared_hwtstamps));
                shhwtstamp->hwtstamp = ns_to_ktime(ns);
        } else  {
                netdev_dbg(priv->dev, "cannot get RX hw timestamp\n");
        }
}

/**
 *  stmmac_hwtstamp_set - control hardware timestamping.
 *  @dev: device pointer.
 *  @ifr: An IOCTL specific structure, that can contain a pointer to
 *  a proprietary structure used to pass information to the driver.
 *  Description:
 *  This function configures the MAC to enable/disable both outgoing(TX)
 *  and incoming(RX) packets time stamping based on user input.
 *  Return Value:
 *  0 on success and an appropriate -ve integer on failure.
 */
static int stmmac_hwtstamp_set(struct net_device *dev, struct ifreq *ifr)
{
        struct stmmac_priv *priv = netdev_priv(dev);
        struct hwtstamp_config config;
        struct timespec64 now;
        u64 temp = 0;
        u32 ptp_v2 = 0;
        u32 tstamp_all = 0;
        u32 ptp_over_ipv4_udp = 0;
        u32 ptp_over_ipv6_udp = 0;
        u32 ptp_over_ethernet = 0;
        u32 snap_type_sel = 0;
        u32 ts_master_en = 0;
        u32 ts_event_en = 0;
        u32 sec_inc = 0;
        u32 value = 0;
        bool xmac;

        xmac = priv->plat->has_gmac4 || priv->plat->has_xgmac;

        if (!(priv->dma_cap.time_stamp || priv->adv_ts)) {
                netdev_alert(priv->dev, "No support for HW time stamping\n");
                priv->hwts_tx_en = 0;
                priv->hwts_rx_en = 0;

                return -EOPNOTSUPP;
        }

        if (copy_from_user(&config, ifr->ifr_data,
                           sizeof(config)))
                return -EFAULT;

        netdev_dbg(priv->dev, "%s config flags:0x%x, tx_type:0x%x, rx_filter:0x%x\n",
                   __func__, config.flags, config.tx_type, config.rx_filter);

        /* reserved for future extensions */
        if (config.flags)
                return -EINVAL;

        if (config.tx_type != HWTSTAMP_TX_OFF &&
            config.tx_type != HWTSTAMP_TX_ON)
                return -ERANGE;

        if (priv->adv_ts) {
                switch (config.rx_filter) {
                case HWTSTAMP_FILTER_NONE:
                        /* time stamp no incoming packet at all */
                        config.rx_filter = HWTSTAMP_FILTER_NONE;
                        break;

                case HWTSTAMP_FILTER_PTP_V1_L4_EVENT:
                        /* PTP v1, UDP, any kind of event packet */
                        config.rx_filter = HWTSTAMP_FILTER_PTP_V1_L4_EVENT;
                        /* 'xmac' hardware can support Sync, Pdelay_Req and
                         * Pdelay_resp by setting bit14 and bits17/16 to 01
                         * This leaves Delay_Req timestamps out.
                         * Enable all events *and* general purpose message
                         * timestamping
                         */
                        snap_type_sel = PTP_TCR_SNAPTYPSEL_1;
                        ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
                        ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
                        break;

                case HWTSTAMP_FILTER_PTP_V1_L4_SYNC:
                        /* PTP v1, UDP, Sync packet */
                        config.rx_filter = HWTSTAMP_FILTER_PTP_V1_L4_SYNC;
                        /* take time stamp for SYNC messages only */
                        ts_event_en = PTP_TCR_TSEVNTENA;

                        ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
                        ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
                        break;

                case HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ:
                        /* PTP v1, UDP, Delay_req packet */
                        config.rx_filter = HWTSTAMP_FILTER_PTP_V1_L4_DELAY_REQ;
                        /* take time stamp for Delay_Req messages only */
                        ts_master_en = PTP_TCR_TSMSTRENA;
                        ts_event_en = PTP_TCR_TSEVNTENA;

                        ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
                        ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
                        break;

                case HWTSTAMP_FILTER_PTP_V2_L4_EVENT:
                        /* PTP v2, UDP, any kind of event packet */
                        config.rx_filter = HWTSTAMP_FILTER_PTP_V2_L4_EVENT;
                        ptp_v2 = PTP_TCR_TSVER2ENA;
                        /* take time stamp for all event messages */
                        snap_type_sel = PTP_TCR_SNAPTYPSEL_1;

                        ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
                        ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
                        break;

                case HWTSTAMP_FILTER_PTP_V2_L4_SYNC:
                        /* PTP v2, UDP, Sync packet */
                        config.rx_filter = HWTSTAMP_FILTER_PTP_V2_L4_SYNC;
                        ptp_v2 = PTP_TCR_TSVER2ENA;
                        /* take time stamp for SYNC messages only */
                        ts_event_en = PTP_TCR_TSEVNTENA;

                        ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
                        ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
                        break;

                case HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ:
                        /* PTP v2, UDP, Delay_req packet */
                        config.rx_filter = HWTSTAMP_FILTER_PTP_V2_L4_DELAY_REQ;
                        ptp_v2 = PTP_TCR_TSVER2ENA;
                        /* take time stamp for Delay_Req messages only */
                        ts_master_en = PTP_TCR_TSMSTRENA;
                        ts_event_en = PTP_TCR_TSEVNTENA;

                        ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
                        ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
                        break;

                case HWTSTAMP_FILTER_PTP_V2_EVENT:
                        /* PTP v2/802.AS1 any layer, any kind of event packet */
                        config.rx_filter = HWTSTAMP_FILTER_PTP_V2_EVENT;
                        ptp_v2 = PTP_TCR_TSVER2ENA;
                        snap_type_sel = PTP_TCR_SNAPTYPSEL_1;
                        ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
                        ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
                        ptp_over_ethernet = PTP_TCR_TSIPENA;
                        break;

                case HWTSTAMP_FILTER_PTP_V2_SYNC:
                        /* PTP v2/802.AS1, any layer, Sync packet */
                        config.rx_filter = HWTSTAMP_FILTER_PTP_V2_SYNC;
                        ptp_v2 = PTP_TCR_TSVER2ENA;
                        /* take time stamp for SYNC messages only */
                        ts_event_en = PTP_TCR_TSEVNTENA;

                        ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
                        ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
                        ptp_over_ethernet = PTP_TCR_TSIPENA;
                        break;

                case HWTSTAMP_FILTER_PTP_V2_DELAY_REQ:
                        /* PTP v2/802.AS1, any layer, Delay_req packet */
                        config.rx_filter = HWTSTAMP_FILTER_PTP_V2_DELAY_REQ;
                        ptp_v2 = PTP_TCR_TSVER2ENA;
                        /* take time stamp for Delay_Req messages only */
                        ts_master_en = PTP_TCR_TSMSTRENA;
                        ts_event_en = PTP_TCR_TSEVNTENA;

                        ptp_over_ipv4_udp = PTP_TCR_TSIPV4ENA;
                        ptp_over_ipv6_udp = PTP_TCR_TSIPV6ENA;
                        ptp_over_ethernet = PTP_TCR_TSIPENA;
                        break;

                case HWTSTAMP_FILTER_NTP_ALL:
                case HWTSTAMP_FILTER_ALL:
                        /* time stamp any incoming packet */
                        config.rx_filter = HWTSTAMP_FILTER_ALL;
                        tstamp_all = PTP_TCR_TSENALL;
                        break;

                default:
                        return -ERANGE;
                }
        } else {
                switch (config.rx_filter) {
                case HWTSTAMP_FILTER_NONE:
                        config.rx_filter = HWTSTAMP_FILTER_NONE;
                        break;
                default:
                        /* PTP v1, UDP, any kind of event packet */
                        config.rx_filter = HWTSTAMP_FILTER_PTP_V1_L4_EVENT;
                        break;
                }
        }
        priv->hwts_rx_en = ((config.rx_filter == HWTSTAMP_FILTER_NONE) ? 0 : 1);
        priv->hwts_tx_en = config.tx_type == HWTSTAMP_TX_ON;

        if (!priv->hwts_tx_en && !priv->hwts_rx_en)
                stmmac_config_hw_tstamping(priv, priv->ptpaddr, 0);
        else {
                value = (PTP_TCR_TSENA | PTP_TCR_TSCFUPDT | PTP_TCR_TSCTRLSSR |
                         tstamp_all | ptp_v2 | ptp_over_ethernet |
                         ptp_over_ipv6_udp | ptp_over_ipv4_udp | ts_event_en |
                         ts_master_en | snap_type_sel);
                stmmac_config_hw_tstamping(priv, priv->ptpaddr, value);

                /* program Sub Second Increment reg */
                stmmac_config_sub_second_increment(priv,
                                priv->ptpaddr, priv->plat->clk_ptp_rate,
                                xmac, &sec_inc);
                temp = div_u64(1000000000ULL, sec_inc);

                /* Store sub second increment and flags for later use */
                priv->sub_second_inc = sec_inc;
                priv->systime_flags = value;

                /* calculate default added value:
                 * formula is :
                 * addend = (2^32)/freq_div_ratio;
                 * where, freq_div_ratio = 1e9ns/sec_inc
                 */
                temp = (u64)(temp << 32);
                priv->default_addend = div_u64(temp, priv->plat->clk_ptp_rate);
                stmmac_config_addend(priv, priv->ptpaddr, priv->default_addend);

                /* initialize system time */
                ktime_get_real_ts64(&now);

                /* lower 32 bits of tv_sec are safe until y2106 */
                stmmac_init_systime(priv, priv->ptpaddr,
                                (u32)now.tv_sec, now.tv_nsec);
        }

        memcpy(&priv->tstamp_config, &config, sizeof(config));

        return copy_to_user(ifr->ifr_data, &config,
                            sizeof(config)) ? -EFAULT : 0;
}

/**
 *  stmmac_hwtstamp_get - read hardware timestamping.
 *  @dev: device pointer.
 *  @ifr: An IOCTL specific structure, that can contain a pointer to
 *  a proprietary structure used to pass information to the driver.
 *  Description:
 *  This function obtain the current hardware timestamping settings
    as requested.
 */
static int stmmac_hwtstamp_get(struct net_device *dev, struct ifreq *ifr)
{
        struct stmmac_priv *priv = netdev_priv(dev);
        struct hwtstamp_config *config = &priv->tstamp_config;

        if (!(priv->dma_cap.time_stamp || priv->dma_cap.atime_stamp))
                return -EOPNOTSUPP;

        return copy_to_user(ifr->ifr_data, config,
                            sizeof(*config)) ? -EFAULT : 0;
}

/**
 * stmmac_init_ptp - init PTP
 * @priv: driver private structure
 * Description: this is to verify if the HW supports the PTPv1 or PTPv2.
 * This is done by looking at the HW cap. register.
 * This function also registers the ptp driver.
 */
static int stmmac_init_ptp(struct stmmac_priv *priv)
{
        bool xmac = priv->plat->has_gmac4 || priv->plat->has_xgmac;

        if (!(priv->dma_cap.time_stamp || priv->dma_cap.atime_stamp))
                return -EOPNOTSUPP;

        priv->adv_ts = 0;
        /* Check if adv_ts can be enabled for dwmac 4.x / xgmac core */
        if (xmac && priv->dma_cap.atime_stamp)
                priv->adv_ts = 1;
        /* Dwmac 3.x core with extend_desc can support adv_ts */
        else if (priv->extend_desc && priv->dma_cap.atime_stamp)
                priv->adv_ts = 1;

        if (priv->dma_cap.time_stamp)
                netdev_info(priv->dev, "IEEE 1588-2002 Timestamp supported\n");

        if (priv->adv_ts)
                netdev_info(priv->dev,
                            "IEEE 1588-2008 Advanced Timestamp supported\n");

        priv->hwts_tx_en = 0;
        priv->hwts_rx_en = 0;

        stmmac_ptp_register(priv);

        return 0;
}

static void stmmac_release_ptp(struct stmmac_priv *priv)
{
        if (priv->plat->clk_ptp_ref)
                clk_disable_unprepare(priv->plat->clk_ptp_ref);
        stmmac_ptp_unregister(priv);
}

/**
 *  stmmac_mac_flow_ctrl - Configure flow control in all queues
 *  @priv: driver private structure
 *  Description: It is used for configuring the flow control in all queues
 */
static void stmmac_mac_flow_ctrl(struct stmmac_priv *priv, u32 duplex)
{
        u32 tx_cnt = priv->plat->tx_queues_to_use;

        stmmac_flow_ctrl(priv, priv->hw, duplex, priv->flow_ctrl,
                        priv->pause, tx_cnt);
}

static void stmmac_validate(struct phylink_config *config,
                            unsigned long *supported,
                            struct phylink_link_state *state)
{
        struct stmmac_priv *priv = netdev_priv(to_net_dev(config->dev));
        __ETHTOOL_DECLARE_LINK_MODE_MASK(mac_supported) = { 0, };
        __ETHTOOL_DECLARE_LINK_MODE_MASK(mask) = { 0, };
        int tx_cnt = priv->plat->tx_queues_to_use;
        int max_speed = priv->plat->max_speed;

        phylink_set(mac_supported, 10baseT_Half);
        phylink_set(mac_supported, 10baseT_Full);
        phylink_set(mac_supported, 100baseT_Half);
        phylink_set(mac_supported, 100baseT_Full);
        phylink_set(mac_supported, 1000baseT_Half);
        phylink_set(mac_supported, 1000baseT_Full);
        phylink_set(mac_supported, 1000baseKX_Full);

        phylink_set(mac_supported, Autoneg);
        phylink_set(mac_supported, Pause);
        phylink_set(mac_supported, Asym_Pause);
        phylink_set_port_modes(mac_supported);

        /* Cut down 1G if asked to */
        if ((max_speed > 0) && (max_speed < 1000)) {
                phylink_set(mask, 1000baseT_Full);
                phylink_set(mask, 1000baseX_Full);
        } else if (priv->plat->has_xgmac) {
                phylink_set(mac_supported, 2500baseT_Full);
                phylink_set(mac_supported, 5000baseT_Full);
                phylink_set(mac_supported, 10000baseSR_Full);
                phylink_set(mac_supported, 10000baseLR_Full);
                phylink_set(mac_supported, 10000baseER_Full);
                phylink_set(mac_supported, 10000baseLRM_Full);
                phylink_set(mac_supported, 10000baseT_Full);
                phylink_set(mac_supported, 10000baseKX4_Full);
                phylink_set(mac_supported, 10000baseKR_Full);
        }

        /* Half-Duplex can only work with single queue */
        if (tx_cnt > 1) {
                phylink_set(mask, 10baseT_Half);
                phylink_set(mask, 100baseT_Half);
                phylink_set(mask, 1000baseT_Half);
        }

        bitmap_and(supported, supported, mac_supported,
                   __ETHTOOL_LINK_MODE_MASK_NBITS);
        bitmap_andnot(supported, supported, mask,
                      __ETHTOOL_LINK_MODE_MASK_NBITS);
        bitmap_and(state->advertising, state->advertising, mac_supported,
                   __ETHTOOL_LINK_MODE_MASK_NBITS);
        bitmap_andnot(state->advertising, state->advertising, mask,
                      __ETHTOOL_LINK_MODE_MASK_NBITS);
}

static int stmmac_mac_link_state(struct phylink_config *config,
                                 struct phylink_link_state *state)
{
        return -EOPNOTSUPP;
}

static void stmmac_mac_config(struct phylink_config *config, unsigned int mode,
                              const struct phylink_link_state *state)
{
        struct stmmac_priv *priv = netdev_priv(to_net_dev(config->dev));
        u32 ctrl;

        ctrl = readl(priv->ioaddr + MAC_CTRL_REG);
        ctrl &= ~priv->hw->link.speed_mask;

        if (state->interface == PHY_INTERFACE_MODE_USXGMII) {
                switch (state->speed) {
                case SPEED_10000:
                        ctrl |= priv->hw->link.xgmii.speed10000;
                        break;
                case SPEED_5000:
                        ctrl |= priv->hw->link.xgmii.speed5000;
                        break;
                case SPEED_2500:
                        ctrl |= priv->hw->link.xgmii.speed2500;
                        break;
                default:
                        return;
                }
        } else {
                switch (state->speed) {
                case SPEED_2500:
                        ctrl |= priv->hw->link.speed2500;
                        break;
                case SPEED_1000:
                        ctrl |= priv->hw->link.speed1000;
                        break;
                case SPEED_100:
                        ctrl |= priv->hw->link.speed100;
                        break;
                case SPEED_10:
                        ctrl |= priv->hw->link.speed10;
                        break;
                default:
                        return;
                }
        }

        priv->speed = state->speed;

        if (priv->plat->fix_mac_speed)
                priv->plat->fix_mac_speed(priv->plat->bsp_priv, state->speed);

        if (!state->duplex)
                ctrl &= ~priv->hw->link.duplex;
        else
                ctrl |= priv->hw->link.duplex;

        /* Flow Control operation */
        if (state->pause)
                stmmac_mac_flow_ctrl(priv, state->duplex);

        writel(ctrl, priv->ioaddr + MAC_CTRL_REG);
}

static void stmmac_mac_an_restart(struct phylink_config *config)
{
        /* Not Supported */
}

static void stmmac_mac_link_down(struct phylink_config *config,
                                 unsigned int mode, phy_interface_t interface)
{
        struct stmmac_priv *priv = netdev_priv(to_net_dev(config->dev));

        stmmac_mac_set(priv, priv->ioaddr, false);
        priv->eee_active = false;
        stmmac_eee_init(priv);
        stmmac_set_eee_pls(priv, priv->hw, false);
}

static void stmmac_mac_link_up(struct phylink_config *config,
                               unsigned int mode, phy_interface_t interface,
                               struct phy_device *phy)
{
        struct stmmac_priv *priv = netdev_priv(to_net_dev(config->dev));

        stmmac_mac_set(priv, priv->ioaddr, true);
        if (phy && priv->dma_cap.eee) {
                priv->eee_active = phy_init_eee(phy, 1) >= 0;
                priv->eee_enabled = stmmac_eee_init(priv);
                stmmac_set_eee_pls(priv, priv->hw, true);
        }
}

static const struct phylink_mac_ops stmmac_phylink_mac_ops = {
        .validate = stmmac_validate,
        .mac_link_state = stmmac_mac_link_state,
        .mac_config = stmmac_mac_config,
        .mac_an_restart = stmmac_mac_an_restart,
        .mac_link_down = stmmac_mac_link_down,
        .mac_link_up = stmmac_mac_link_up,
};

/**
 * stmmac_check_pcs_mode - verify if RGMII/SGMII is supported
 * @priv: driver private structure
 * Description: this is to verify if the HW supports the PCS.
 * Physical Coding Sublayer (PCS) interface that can be used when the MAC is
 * configured for the TBI, RTBI, or SGMII PHY interface.
 */
static void stmmac_check_pcs_mode(struct stmmac_priv *priv)
{
        int interface = priv->plat->interface;

        if (priv->dma_cap.pcs) {
                if ((interface == PHY_INTERFACE_MODE_RGMII) ||
                    (interface == PHY_INTERFACE_MODE_RGMII_ID) ||
                    (interface == PHY_INTERFACE_MODE_RGMII_RXID) ||
                    (interface == PHY_INTERFACE_MODE_RGMII_TXID)) {
                        netdev_dbg(priv->dev, "PCS RGMII support enabled\n");
                        priv->hw->pcs = STMMAC_PCS_RGMII;
                } else if (interface == PHY_INTERFACE_MODE_SGMII) {
                        netdev_dbg(priv->dev, "PCS SGMII support enabled\n");
                        priv->hw->pcs = STMMAC_PCS_SGMII;
                }
        }
}

/**
 * stmmac_init_phy - PHY initialization
 * @dev: net device structure
 * Description: it initializes the driver's PHY state, and attaches the PHY
 * to the mac driver.
 *  Return value:
 *  0 on success
 */
static int stmmac_init_phy(struct net_device *dev)
{
        struct stmmac_priv *priv = netdev_priv(dev);
        struct device_node *node;
        int ret;

        node = priv->plat->phylink_node;

        if (node)
                ret = phylink_of_phy_connect(priv->phylink, node, 0);

        /* Some DT bindings do not set-up the PHY handle. Let's try to
         * manually parse it
         */
        if (!node || ret) {
                int addr = priv->plat->phy_addr;
                struct phy_device *phydev;

                phydev = mdiobus_get_phy(priv->mii, addr);
                if (!phydev) {
                        netdev_err(priv->dev, "no phy at addr %d\n", addr);
                        return -ENODEV;
                }

                ret = phylink_connect_phy(priv->phylink, phydev);
        }

        return ret;
}

static int stmmac_phy_setup(struct stmmac_priv *priv)
{
        struct fwnode_handle *fwnode = of_fwnode_handle(priv->plat->phylink_node);
        int mode = priv->plat->interface;
        struct phylink *phylink;

        priv->phylink_config.dev = &priv->dev->dev;
        priv->phylink_config.type = PHYLINK_NETDEV;

        phylink = phylink_create(&priv->phylink_config, fwnode,
                                 mode, &stmmac_phylink_mac_ops);
        if (IS_ERR(phylink))
                return PTR_ERR(phylink);

        priv->phylink = phylink;
        return 0;
}

static void stmmac_display_rx_rings(struct stmmac_priv *priv)
{
        u32 rx_cnt = priv->plat->rx_queues_to_use;
        void *head_rx;
        u32 queue;

        /* Display RX rings */
        for (queue = 0; queue < rx_cnt; queue++) {
                struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];

                pr_info("\tRX Queue %u rings\n", queue);

                if (priv->extend_desc)
                        head_rx = (void *)rx_q->dma_erx;
                else
                        head_rx = (void *)rx_q->dma_rx;

                /* Display RX ring */
                stmmac_display_ring(priv, head_rx, DMA_RX_SIZE, true);
        }
}

static void stmmac_display_tx_rings(struct stmmac_priv *priv)
{
        u32 tx_cnt = priv->plat->tx_queues_to_use;
        void *head_tx;
        u32 queue;

        /* Display TX rings */
        for (queue = 0; queue < tx_cnt; queue++) {
                struct stmmac_tx_queue *tx_q = &priv->tx_queue[queue];

                pr_info("\tTX Queue %d rings\n", queue);

                if (priv->extend_desc)
                        head_tx = (void *)tx_q->dma_etx;
                else
                        head_tx = (void *)tx_q->dma_tx;

                stmmac_display_ring(priv, head_tx, DMA_TX_SIZE, false);
        }
}

static void stmmac_display_rings(struct stmmac_priv *priv)
{
        /* Display RX ring */
        stmmac_display_rx_rings(priv);

        /* Display TX ring */
        stmmac_display_tx_rings(priv);
}

static int stmmac_set_bfsize(int mtu, int bufsize)
{
        int ret = bufsize;

        if (mtu >= BUF_SIZE_4KiB)
                ret = BUF_SIZE_8KiB;
        else if (mtu >= BUF_SIZE_2KiB)
                ret = BUF_SIZE_4KiB;
        else if (mtu > DEFAULT_BUFSIZE)
                ret = BUF_SIZE_2KiB;
        else
                ret = DEFAULT_BUFSIZE;

        return ret;
}

/**
 * stmmac_clear_rx_descriptors - clear RX descriptors
 * @priv: driver private structure
 * @queue: RX queue index
 * Description: this function is called to clear the RX descriptors
 * in case of both basic and extended descriptors are used.
 */
static void stmmac_clear_rx_descriptors(struct stmmac_priv *priv, u32 queue)
{
        struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];
        int i;

        /* Clear the RX descriptors */
        for (i = 0; i < DMA_RX_SIZE; i++)
                if (priv->extend_desc)
                        stmmac_init_rx_desc(priv, &rx_q->dma_erx[i].basic,
                                        priv->use_riwt, priv->mode,
                                        (i == DMA_RX_SIZE - 1),
                                        priv->dma_buf_sz);
                else
                        stmmac_init_rx_desc(priv, &rx_q->dma_rx[i],
                                        priv->use_riwt, priv->mode,
                                        (i == DMA_RX_SIZE - 1),
                                        priv->dma_buf_sz);
}

/**
 * stmmac_clear_tx_descriptors - clear tx descriptors
 * @priv: driver private structure
 * @queue: TX queue index.
 * Description: this function is called to clear the TX descriptors
 * in case of both basic and extended descriptors are used.
 */
static void stmmac_clear_tx_descriptors(struct stmmac_priv *priv, u32 queue)
{
        struct stmmac_tx_queue *tx_q = &priv->tx_queue[queue];
        int i;

        /* Clear the TX descriptors */
        for (i = 0; i < DMA_TX_SIZE; i++)
                if (priv->extend_desc)
                        stmmac_init_tx_desc(priv, &tx_q->dma_etx[i].basic,
                                        priv->mode, (i == DMA_TX_SIZE - 1));
                else
                        stmmac_init_tx_desc(priv, &tx_q->dma_tx[i],
                                        priv->mode, (i == DMA_TX_SIZE - 1));
}

/**
 * stmmac_clear_descriptors - clear descriptors
 * @priv: driver private structure
 * Description: this function is called to clear the TX and RX descriptors
 * in case of both basic and extended descriptors are used.
 */
static void stmmac_clear_descriptors(struct stmmac_priv *priv)
{
        u32 rx_queue_cnt = priv->plat->rx_queues_to_use;
        u32 tx_queue_cnt = priv->plat->tx_queues_to_use;
        u32 queue;

        /* Clear the RX descriptors */
        for (queue = 0; queue < rx_queue_cnt; queue++)
                stmmac_clear_rx_descriptors(priv, queue);

        /* Clear the TX descriptors */
        for (queue = 0; queue < tx_queue_cnt; queue++)
                stmmac_clear_tx_descriptors(priv, queue);
}

/**
 * stmmac_init_rx_buffers - init the RX descriptor buffer.
 * @priv: driver private structure
 * @p: descriptor pointer
 * @i: descriptor index
 * @flags: gfp flag
 * @queue: RX queue index
 * Description: this function is called to allocate a receive buffer, perform
 * the DMA mapping and init the descriptor.
 */
static int stmmac_init_rx_buffers(struct stmmac_priv *priv, struct dma_desc *p,
                                  int i, gfp_t flags, u32 queue)
{
        struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];
        struct stmmac_rx_buffer *buf = &rx_q->buf_pool[i];

        buf->page = page_pool_dev_alloc_pages(rx_q->page_pool);
        if (!buf->page)
                return -ENOMEM;

        buf->addr = page_pool_get_dma_addr(buf->page);
        stmmac_set_desc_addr(priv, p, buf->addr);
        if (priv->dma_buf_sz == BUF_SIZE_16KiB)
                stmmac_init_desc3(priv, p);

        return 0;
}

/**
 * stmmac_free_rx_buffer - free RX dma buffers
 * @priv: private structure
 * @queue: RX queue index
 * @i: buffer index.
 */
static void stmmac_free_rx_buffer(struct stmmac_priv *priv, u32 queue, int i)
{
        struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];
        struct stmmac_rx_buffer *buf = &rx_q->buf_pool[i];

        if (buf->page)
                page_pool_put_page(rx_q->page_pool, buf->page, false);
        buf->page = NULL;
}

/**
 * stmmac_free_tx_buffer - free RX dma buffers
 * @priv: private structure
 * @queue: RX queue index
 * @i: buffer index.
 */
static void stmmac_free_tx_buffer(struct stmmac_priv *priv, u32 queue, int i)
{
        struct stmmac_tx_queue *tx_q = &priv->tx_queue[queue];

        if (tx_q->tx_skbuff_dma[i].buf) {
                if (tx_q->tx_skbuff_dma[i].map_as_page)
                        dma_unmap_page(priv->device,
                                       tx_q->tx_skbuff_dma[i].buf,
                                       tx_q->tx_skbuff_dma[i].len,
                                       DMA_TO_DEVICE);
                else
                        dma_unmap_single(priv->device,
                                         tx_q->tx_skbuff_dma[i].buf,
                                         tx_q->tx_skbuff_dma[i].len,
                                         DMA_TO_DEVICE);
        }

        if (tx_q->tx_skbuff[i]) {
                dev_kfree_skb_any(tx_q->tx_skbuff[i]);
                tx_q->tx_skbuff[i] = NULL;
                tx_q->tx_skbuff_dma[i].buf = 0;
                tx_q->tx_skbuff_dma[i].map_as_page = false;
        }
}

/**
 * init_dma_rx_desc_rings - init the RX descriptor rings
 * @dev: net device structure
 * @flags: gfp flag.
 * Description: this function initializes the DMA RX descriptors
 * and allocates the socket buffers. It supports the chained and ring
 * modes.
 */
static int init_dma_rx_desc_rings(struct net_device *dev, gfp_t flags)
{
        struct stmmac_priv *priv = netdev_priv(dev);
        u32 rx_count = priv->plat->rx_queues_to_use;
        int ret = -ENOMEM;
        int bfsize = 0;
        int queue;
        int i;

        bfsize = stmmac_set_16kib_bfsize(priv, dev->mtu);
        if (bfsize < 0)
                bfsize = 0;

        if (bfsize < BUF_SIZE_16KiB)
                bfsize = stmmac_set_bfsize(dev->mtu, priv->dma_buf_sz);

        priv->dma_buf_sz = bfsize;

        /* RX INITIALIZATION */
        netif_dbg(priv, probe, priv->dev,
                  "SKB addresses:\nskb\t\tskb data\tdma data\n");

        for (queue = 0; queue < rx_count; queue++) {
                struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];

                netif_dbg(priv, probe, priv->dev,
                          "(%s) dma_rx_phy=0x%08x\n", __func__,
                          (u32)rx_q->dma_rx_phy);

                stmmac_clear_rx_descriptors(priv, queue);

                for (i = 0; i < DMA_RX_SIZE; i++) {
                        struct dma_desc *p;

                        if (priv->extend_desc)
                                p = &((rx_q->dma_erx + i)->basic);
                        else
                                p = rx_q->dma_rx + i;

                        ret = stmmac_init_rx_buffers(priv, p, i, flags,
                                                     queue);
                        if (ret)
                                goto err_init_rx_buffers;
                }

                rx_q->cur_rx = 0;
                rx_q->dirty_rx = (unsigned int)(i - DMA_RX_SIZE);

                /* Setup the chained descriptor addresses */
                if (priv->mode == STMMAC_CHAIN_MODE) {
                        if (priv->extend_desc)
                                stmmac_mode_init(priv, rx_q->dma_erx,
                                                rx_q->dma_rx_phy, DMA_RX_SIZE, 1);
                        else
                                stmmac_mode_init(priv, rx_q->dma_rx,
                                                rx_q->dma_rx_phy, DMA_RX_SIZE, 0);
                }
        }

        buf_sz = bfsize;

        return 0;

err_init_rx_buffers:
        while (queue >= 0) {
                while (--i >= 0)
                        stmmac_free_rx_buffer(priv, queue, i);

                if (queue == 0)
                        break;

                i = DMA_RX_SIZE;
                queue--;
        }

        return ret;
}

/**
 * init_dma_tx_desc_rings - init the TX descriptor rings
 * @dev: net device structure.
 * Description: this function initializes the DMA TX descriptors
 * and allocates the socket buffers. It supports the chained and ring
 * modes.
 */
static int init_dma_tx_desc_rings(struct net_device *dev)
{
        struct stmmac_priv *priv = netdev_priv(dev);
        u32 tx_queue_cnt = priv->plat->tx_queues_to_use;
        u32 queue;
        int i;

        for (queue = 0; queue < tx_queue_cnt; queue++) {
                struct stmmac_tx_queue *tx_q = &priv->tx_queue[queue];

                netif_dbg(priv, probe, priv->dev,
                          "(%s) dma_tx_phy=0x%08x\n", __func__,
                         (u32)tx_q->dma_tx_phy);

                /* Setup the chained descriptor addresses */
                if (priv->mode == STMMAC_CHAIN_MODE) {
                        if (priv->extend_desc)
                                stmmac_mode_init(priv, tx_q->dma_etx,
                                                tx_q->dma_tx_phy, DMA_TX_SIZE, 1);
                        else
                                stmmac_mode_init(priv, tx_q->dma_tx,
                                                tx_q->dma_tx_phy, DMA_TX_SIZE, 0);
                }

                for (i = 0; i < DMA_TX_SIZE; i++) {
                        struct dma_desc *p;
                        if (priv->extend_desc)
                                p = &((tx_q->dma_etx + i)->basic);
                        else
                                p = tx_q->dma_tx + i;

                        stmmac_clear_desc(priv, p);

                        tx_q->tx_skbuff_dma[i].buf = 0;
                        tx_q->tx_skbuff_dma[i].map_as_page = false;
                        tx_q->tx_skbuff_dma[i].len = 0;
                        tx_q->tx_skbuff_dma[i].last_segment = false;
                        tx_q->tx_skbuff[i] = NULL;
                }

                tx_q->dirty_tx = 0;
                tx_q->cur_tx = 0;
                tx_q->mss = 0;

                netdev_tx_reset_queue(netdev_get_tx_queue(priv->dev, queue));
        }

        return 0;
}

/**
 * init_dma_desc_rings - init the RX/TX descriptor rings
 * @dev: net device structure
 * @flags: gfp flag.
 * Description: this function initializes the DMA RX/TX descriptors
 * and allocates the socket buffers. It supports the chained and ring
 * modes.
 */
static int init_dma_desc_rings(struct net_device *dev, gfp_t flags)
{
        struct stmmac_priv *priv = netdev_priv(dev);
        int ret;

        ret = init_dma_rx_desc_rings(dev, flags);
        if (ret)
                return ret;

        ret = init_dma_tx_desc_rings(dev);

        stmmac_clear_descriptors(priv);

        if (netif_msg_hw(priv))
                stmmac_display_rings(priv);

        return ret;
}

/**
 * dma_free_rx_skbufs - free RX dma buffers
 * @priv: private structure
 * @queue: RX queue index
 */
static void dma_free_rx_skbufs(struct stmmac_priv *priv, u32 queue)
{
        int i;

        for (i = 0; i < DMA_RX_SIZE; i++)
                stmmac_free_rx_buffer(priv, queue, i);
}

/**
 * dma_free_tx_skbufs - free TX dma buffers
 * @priv: private structure
 * @queue: TX queue index
 */
static void dma_free_tx_skbufs(struct stmmac_priv *priv, u32 queue)
{
        int i;

        for (i = 0; i < DMA_TX_SIZE; i++)
                stmmac_free_tx_buffer(priv, queue, i);
}

/**
 * free_dma_rx_desc_resources - free RX dma desc resources
 * @priv: private structure
 */
static void free_dma_rx_desc_resources(struct stmmac_priv *priv)
{
        u32 rx_count = priv->plat->rx_queues_to_use;
        u32 queue;

        /* Free RX queue resources */
        for (queue = 0; queue < rx_count; queue++) {
                struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];

                /* Release the DMA RX socket buffers */
                dma_free_rx_skbufs(priv, queue);

                /* Free DMA regions of consistent memory previously allocated */
                if (!priv->extend_desc)
                        dma_free_coherent(priv->device,
                                          DMA_RX_SIZE * sizeof(struct dma_desc),
                                          rx_q->dma_rx, rx_q->dma_rx_phy);
                else
                        dma_free_coherent(priv->device, DMA_RX_SIZE *
                                          sizeof(struct dma_extended_desc),
                                          rx_q->dma_erx, rx_q->dma_rx_phy);

                kfree(rx_q->buf_pool);
                if (rx_q->page_pool) {
                        page_pool_request_shutdown(rx_q->page_pool);
                        page_pool_destroy(rx_q->page_pool);
                }
        }
}

/**
 * free_dma_tx_desc_resources - free TX dma desc resources
 * @priv: private structure
 */
static void free_dma_tx_desc_resources(struct stmmac_priv *priv)
{
        u32 tx_count = priv->plat->tx_queues_to_use;
        u32 queue;

        /* Free TX queue resources */
        for (queue = 0; queue < tx_count; queue++) {
                struct stmmac_tx_queue *tx_q = &priv->tx_queue[queue];

                /* Release the DMA TX socket buffers */
                dma_free_tx_skbufs(priv, queue);

                /* Free DMA regions of consistent memory previously allocated */
                if (!priv->extend_desc)
                        dma_free_coherent(priv->device,
                                          DMA_TX_SIZE * sizeof(struct dma_desc),
                                          tx_q->dma_tx, tx_q->dma_tx_phy);
                else
                        dma_free_coherent(priv->device, DMA_TX_SIZE *
                                          sizeof(struct dma_extended_desc),
                                          tx_q->dma_etx, tx_q->dma_tx_phy);

                kfree(tx_q->tx_skbuff_dma);
                kfree(tx_q->tx_skbuff);
        }
}

/**
 * alloc_dma_rx_desc_resources - alloc RX resources.
 * @priv: private structure
 * Description: according to which descriptor can be used (extend or basic)
 * this function allocates the resources for TX and RX paths. In case of
 * reception, for example, it pre-allocated the RX socket buffer in order to
 * allow zero-copy mechanism.
 */
static int alloc_dma_rx_desc_resources(struct stmmac_priv *priv)
{
        u32 rx_count = priv->plat->rx_queues_to_use;
        int ret = -ENOMEM;
        u32 queue;

        /* RX queues buffers and DMA */
        for (queue = 0; queue < rx_count; queue++) {
                struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];
                struct page_pool_params pp_params = { 0 };

                rx_q->queue_index = queue;
                rx_q->priv_data = priv;

                pp_params.flags = PP_FLAG_DMA_MAP;
                pp_params.pool_size = DMA_RX_SIZE;
                pp_params.order = DIV_ROUND_UP(priv->dma_buf_sz, PAGE_SIZE);
                pp_params.nid = dev_to_node(priv->device);
                pp_params.dev = priv->device;
                pp_params.dma_dir = DMA_FROM_DEVICE;

                rx_q->page_pool = page_pool_create(&pp_params);
                if (IS_ERR(rx_q->page_pool)) {
                        ret = PTR_ERR(rx_q->page_pool);
                        rx_q->page_pool = NULL;
                        goto err_dma;
                }

                rx_q->buf_pool = kcalloc(DMA_RX_SIZE, sizeof(*rx_q->buf_pool),
                                         GFP_KERNEL);
                if (!rx_q->buf_pool)
                        goto err_dma;

                if (priv->extend_desc) {
                        rx_q->dma_erx = dma_alloc_coherent(priv->device,
                                                           DMA_RX_SIZE * sizeof(struct dma_extended_desc),
                                                           &rx_q->dma_rx_phy,
                                                           GFP_KERNEL);
                        if (!rx_q->dma_erx)
                                goto err_dma;

                } else {
                        rx_q->dma_rx = dma_alloc_coherent(priv->device,
                                                          DMA_RX_SIZE * sizeof(struct dma_desc),
                                                          &rx_q->dma_rx_phy,
                                                          GFP_KERNEL);
                        if (!rx_q->dma_rx)
                                goto err_dma;
                }
        }

        return 0;

err_dma:
        free_dma_rx_desc_resources(priv);

        return ret;
}

/**
 * alloc_dma_tx_desc_resources - alloc TX resources.
 * @priv: private structure
 * Description: according to which descriptor can be used (extend or basic)
 * this function allocates the resources for TX and RX paths. In case of
 * reception, for example, it pre-allocated the RX socket buffer in order to
 * allow zero-copy mechanism.
 */
static int alloc_dma_tx_desc_resources(struct stmmac_priv *priv)
{
        u32 tx_count = priv->plat->tx_queues_to_use;
        int ret = -ENOMEM;
        u32 queue;

        /* TX queues buffers and DMA */
        for (queue = 0; queue < tx_count; queue++) {
                struct stmmac_tx_queue *tx_q = &priv->tx_queue[queue];

                tx_q->queue_index = queue;
                tx_q->priv_data = priv;

                tx_q->tx_skbuff_dma = kcalloc(DMA_TX_SIZE,
                                              sizeof(*tx_q->tx_skbuff_dma),
                                              GFP_KERNEL);
                if (!tx_q->tx_skbuff_dma)
                        goto err_dma;

                tx_q->tx_skbuff = kcalloc(DMA_TX_SIZE,
                                          sizeof(struct sk_buff *),
                                          GFP_KERNEL);
                if (!tx_q->tx_skbuff)
                        goto err_dma;

                if (priv->extend_desc) {
                        tx_q->dma_etx = dma_alloc_coherent(priv->device,
                                                           DMA_TX_SIZE * sizeof(struct dma_extended_desc),
                                                           &tx_q->dma_tx_phy,
                                                           GFP_KERNEL);
                        if (!tx_q->dma_etx)
                                goto err_dma;
                } else {
                        tx_q->dma_tx = dma_alloc_coherent(priv->device,
                                                          DMA_TX_SIZE * sizeof(struct dma_desc),
                                                          &tx_q->dma_tx_phy,
                                                          GFP_KERNEL);
                        if (!tx_q->dma_tx)
                                goto err_dma;
                }
        }

        return 0;

err_dma:
        free_dma_tx_desc_resources(priv);

        return ret;
}

/**
 * alloc_dma_desc_resources - alloc TX/RX resources.
 * @priv: private structure
 * Description: according to which descriptor can be used (extend or basic)
 * this function allocates the resources for TX and RX paths. In case of
 * reception, for example, it pre-allocated the RX socket buffer in order to
 * allow zero-copy mechanism.
 */
static int alloc_dma_desc_resources(struct stmmac_priv *priv)
{
        /* RX Allocation */
        int ret = alloc_dma_rx_desc_resources(priv);

        if (ret)
                return ret;

        ret = alloc_dma_tx_desc_resources(priv);

        return ret;
}

/**
 * free_dma_desc_resources - free dma desc resources
 * @priv: private structure
 */
static void free_dma_desc_resources(struct stmmac_priv *priv)
{
        /* Release the DMA RX socket buffers */
        free_dma_rx_desc_resources(priv);

        /* Release the DMA TX socket buffers */
        free_dma_tx_desc_resources(priv);
}

/**
 *  stmmac_mac_enable_rx_queues - Enable MAC rx queues
 *  @priv: driver private structure
 *  Description: It is used for enabling the rx queues in the MAC
 */
static void stmmac_mac_enable_rx_queues(struct stmmac_priv *priv)
{
        u32 rx_queues_count = priv->plat->rx_queues_to_use;
        int queue;
        u8 mode;

        for (queue = 0; queue < rx_queues_count; queue++) {
                mode = priv->plat->rx_queues_cfg[queue].mode_to_use;
                stmmac_rx_queue_enable(priv, priv->hw, mode, queue);
        }
}

/**
 * stmmac_start_rx_dma - start RX DMA channel
 * @priv: driver private structure
 * @chan: RX channel index
 * Description:
 * This starts a RX DMA channel
 */
static void stmmac_start_rx_dma(struct stmmac_priv *priv, u32 chan)
{
        netdev_dbg(priv->dev, "DMA RX processes started in channel %d\n", chan);
        stmmac_start_rx(priv, priv->ioaddr, chan);
}

/**
 * stmmac_start_tx_dma - start TX DMA channel
 * @priv: driver private structure
 * @chan: TX channel index
 * Description:
 * This starts a TX DMA channel
 */
static void stmmac_start_tx_dma(struct stmmac_priv *priv, u32 chan)
{
        netdev_dbg(priv->dev, "DMA TX processes started in channel %d\n", chan);
        stmmac_start_tx(priv, priv->ioaddr, chan);
}

/**
 * stmmac_stop_rx_dma - stop RX DMA channel
 * @priv: driver private structure
 * @chan: RX channel index
 * Description:
 * This stops a RX DMA channel
 */
static void stmmac_stop_rx_dma(struct stmmac_priv *priv, u32 chan)
{
        netdev_dbg(priv->dev, "DMA RX processes stopped in channel %d\n", chan);
        stmmac_stop_rx(priv, priv->ioaddr, chan);
}

/**
 * stmmac_stop_tx_dma - stop TX DMA channel
 * @priv: driver private structure
 * @chan: TX channel index
 * Description:
 * This stops a TX DMA channel
 */
static void stmmac_stop_tx_dma(struct stmmac_priv *priv, u32 chan)
{
        netdev_dbg(priv->dev, "DMA TX processes stopped in channel %d\n", chan);
        stmmac_stop_tx(priv, priv->ioaddr, chan);
}

/**
 * stmmac_start_all_dma - start all RX and TX DMA channels
 * @priv: driver private structure
 * Description:
 * This starts all the RX and TX DMA channels
 */
static void stmmac_start_all_dma(struct stmmac_priv *priv)
{
        u32 rx_channels_count = priv->plat->rx_queues_to_use;
        u32 tx_channels_count = priv->plat->tx_queues_to_use;
        u32 chan = 0;

        for (chan = 0; chan < rx_channels_count; chan++)
                stmmac_start_rx_dma(priv, chan);

        for (chan = 0; chan < tx_channels_count; chan++)
                stmmac_start_tx_dma(priv, chan);
}

/**
 * stmmac_stop_all_dma - stop all RX and TX DMA channels
 * @priv: driver private structure
 * Description:
 * This stops the RX and TX DMA channels
 */
static void stmmac_stop_all_dma(struct stmmac_priv *priv)
{
        u32 rx_channels_count = priv->plat->rx_queues_to_use;
        u32 tx_channels_count = priv->plat->tx_queues_to_use;
        u32 chan = 0;

        for (chan = 0; chan < rx_channels_count; chan++)
                stmmac_stop_rx_dma(priv, chan);

        for (chan = 0; chan < tx_channels_count; chan++)
                stmmac_stop_tx_dma(priv, chan);
}

/**
 *  stmmac_dma_operation_mode - HW DMA operation mode
 *  @priv: driver private structure
 *  Description: it is used for configuring the DMA operation mode register in
 *  order to program the tx/rx DMA thresholds or Store-And-Forward mode.
 */
static void stmmac_dma_operation_mode(struct stmmac_priv *priv)
{
        u32 rx_channels_count = priv->plat->rx_queues_to_use;
        u32 tx_channels_count = priv->plat->tx_queues_to_use;
        int rxfifosz = priv->plat->rx_fifo_size;
        int txfifosz = priv->plat->tx_fifo_size;
        u32 txmode = 0;
        u32 rxmode = 0;
        u32 chan = 0;
        u8 qmode = 0;

        if (rxfifosz == 0)
                rxfifosz = priv->dma_cap.rx_fifo_size;
        if (txfifosz == 0)
                txfifosz = priv->dma_cap.tx_fifo_size;

        /* Adjust for real per queue fifo size */
        rxfifosz /= rx_channels_count;
        txfifosz /= tx_channels_count;

        if (priv->plat->force_thresh_dma_mode) {
                txmode = tc;
                rxmode = tc;
        } else if (priv->plat->force_sf_dma_mode || priv->plat->tx_coe) {
                /*
                 * In case of GMAC, SF mode can be enabled
                 * to perform the TX COE in HW. This depends on:
                 * 1) TX COE if actually supported
                 * 2) There is no bugged Jumbo frame support
                 *    that needs to not insert csum in the TDES.
                 */
                txmode = SF_DMA_MODE;
                rxmode = SF_DMA_MODE;
                priv->xstats.threshold = SF_DMA_MODE;
        } else {
                txmode = tc;
                rxmode = SF_DMA_MODE;
        }

        /* configure all channels */
        for (chan = 0; chan < rx_channels_count; chan++) {
                qmode = priv->plat->rx_queues_cfg[chan].mode_to_use;

                stmmac_dma_rx_mode(priv, priv->ioaddr, rxmode, chan,
                                rxfifosz, qmode);
                stmmac_set_dma_bfsize(priv, priv->ioaddr, priv->dma_buf_sz,
                                chan);
        }

        for (chan = 0; chan < tx_channels_count; chan++) {
                qmode = priv->plat->tx_queues_cfg[chan].mode_to_use;

                stmmac_dma_tx_mode(priv, priv->ioaddr, txmode, chan,
                                txfifosz, qmode);
        }
}

/**
 * stmmac_tx_clean - to manage the transmission completion
 * @priv: driver private structure
 * @queue: TX queue index
 * Description: it reclaims the transmit resources after transmission completes.
 */
static int stmmac_tx_clean(struct stmmac_priv *priv, int budget, u32 queue)
{
        struct stmmac_tx_queue *tx_q = &priv->tx_queue[queue];
        unsigned int bytes_compl = 0, pkts_compl = 0;
        unsigned int entry, count = 0;

        __netif_tx_lock_bh(netdev_get_tx_queue(priv->dev, queue));

        priv->xstats.tx_clean++;

        entry = tx_q->dirty_tx;
        while ((entry != tx_q->cur_tx) && (count < budget)) {
                struct sk_buff *skb = tx_q->tx_skbuff[entry];
                struct dma_desc *p;
                int status;

                if (priv->extend_desc)
                        p = (struct dma_desc *)(tx_q->dma_etx + entry);
                else
                        p = tx_q->dma_tx + entry;

                status = stmmac_tx_status(priv, &priv->dev->stats,
                                &priv->xstats, p, priv->ioaddr);
                /* Check if the descriptor is owned by the DMA */
                if (unlikely(status & tx_dma_own))
                        break;

                count++;

                /* Make sure descriptor fields are read after reading
                 * the own bit.
                 */
                dma_rmb();

                /* Just consider the last segment and ...*/
                if (likely(!(status & tx_not_ls))) {
                        /* ... verify the status error condition */
                        if (unlikely(status & tx_err)) {
                                priv->dev->stats.tx_errors++;
                        } else {
                                priv->dev->stats.tx_packets++;
                                priv->xstats.tx_pkt_n++;
                        }
                        stmmac_get_tx_hwtstamp(priv, p, skb);
                }

                if (likely(tx_q->tx_skbuff_dma[entry].buf)) {
                        if (tx_q->tx_skbuff_dma[entry].map_as_page)
                                dma_unmap_page(priv->device,
                                               tx_q->tx_skbuff_dma[entry].buf,
                                               tx_q->tx_skbuff_dma[entry].len,
                                               DMA_TO_DEVICE);
                        else
                                dma_unmap_single(priv->device,
                                                 tx_q->tx_skbuff_dma[entry].buf,
                                                 tx_q->tx_skbuff_dma[entry].len,
                                                 DMA_TO_DEVICE);
                        tx_q->tx_skbuff_dma[entry].buf = 0;
                        tx_q->tx_skbuff_dma[entry].len = 0;
                        tx_q->tx_skbuff_dma[entry].map_as_page = false;
                }

                stmmac_clean_desc3(priv, tx_q, p);

                tx_q->tx_skbuff_dma[entry].last_segment = false;
                tx_q->tx_skbuff_dma[entry].is_jumbo = false;

                if (likely(skb != NULL)) {
                        pkts_compl++;
                        bytes_compl += skb->len;
                        dev_consume_skb_any(skb);
                        tx_q->tx_skbuff[entry] = NULL;
                }

                stmmac_release_tx_desc(priv, p, priv->mode);

                entry = STMMAC_GET_ENTRY(entry, DMA_TX_SIZE);
        }
        tx_q->dirty_tx = entry;

        netdev_tx_completed_queue(netdev_get_tx_queue(priv->dev, queue),
                                  pkts_compl, bytes_compl);

        if (unlikely(netif_tx_queue_stopped(netdev_get_tx_queue(priv->dev,
                                                                queue))) &&
            stmmac_tx_avail(priv, queue) > STMMAC_TX_THRESH) {

                netif_dbg(priv, tx_done, priv->dev,
                          "%s: restart transmit\n", __func__);
                netif_tx_wake_queue(netdev_get_tx_queue(priv->dev, queue));
        }

        if ((priv->eee_enabled) && (!priv->tx_path_in_lpi_mode)) {
                stmmac_enable_eee_mode(priv);
                mod_timer(&priv->eee_ctrl_timer, STMMAC_LPI_T(eee_timer));
        }

        /* We still have pending packets, let's call for a new scheduling */
        if (tx_q->dirty_tx != tx_q->cur_tx)
                mod_timer(&tx_q->txtimer, STMMAC_COAL_TIMER(10));

        __netif_tx_unlock_bh(netdev_get_tx_queue(priv->dev, queue));

        return count;
}

/**
 * stmmac_tx_err - to manage the tx error
 * @priv: driver private structure
 * @chan: channel index
 * Description: it cleans the descriptors and restarts the transmission
 * in case of transmission errors.
 */
static void stmmac_tx_err(struct stmmac_priv *priv, u32 chan)
{
        struct stmmac_tx_queue *tx_q = &priv->tx_queue[chan];
        int i;

        netif_tx_stop_queue(netdev_get_tx_queue(priv->dev, chan));

        stmmac_stop_tx_dma(priv, chan);
        dma_free_tx_skbufs(priv, chan);
        for (i = 0; i < DMA_TX_SIZE; i++)
                if (priv->extend_desc)
                        stmmac_init_tx_desc(priv, &tx_q->dma_etx[i].basic,
                                        priv->mode, (i == DMA_TX_SIZE - 1));
                else
                        stmmac_init_tx_desc(priv, &tx_q->dma_tx[i],
                                        priv->mode, (i == DMA_TX_SIZE - 1));
        tx_q->dirty_tx = 0;
        tx_q->cur_tx = 0;
        tx_q->mss = 0;
        netdev_tx_reset_queue(netdev_get_tx_queue(priv->dev, chan));
        stmmac_start_tx_dma(priv, chan);

        priv->dev->stats.tx_errors++;
        netif_tx_wake_queue(netdev_get_tx_queue(priv->dev, chan));
}

/**
 *  stmmac_set_dma_operation_mode - Set DMA operation mode by channel
 *  @priv: driver private structure
 *  @txmode: TX operating mode
 *  @rxmode: RX operating mode
 *  @chan: channel index
 *  Description: it is used for configuring of the DMA operation mode in
 *  runtime in order to program the tx/rx DMA thresholds or Store-And-Forward
 *  mode.
 */
static void stmmac_set_dma_operation_mode(struct stmmac_priv *priv, u32 txmode,
                                          u32 rxmode, u32 chan)
{
        u8 rxqmode = priv->plat->rx_queues_cfg[chan].mode_to_use;
        u8 txqmode = priv->plat->tx_queues_cfg[chan].mode_to_use;
        u32 rx_channels_count = priv->plat->rx_queues_to_use;
        u32 tx_channels_count = priv->plat->tx_queues_to_use;
        int rxfifosz = priv->plat->rx_fifo_size;
        int txfifosz = priv->plat->tx_fifo_size;

        if (rxfifosz == 0)
                rxfifosz = priv->dma_cap.rx_fifo_size;
        if (txfifosz == 0)
                txfifosz = priv->dma_cap.tx_fifo_size;

        /* Adjust for real per queue fifo size */
        rxfifosz /= rx_channels_count;
        txfifosz /= tx_channels_count;

        stmmac_dma_rx_mode(priv, priv->ioaddr, rxmode, chan, rxfifosz, rxqmode);
        stmmac_dma_tx_mode(priv, priv->ioaddr, txmode, chan, txfifosz, txqmode);
}

static bool stmmac_safety_feat_interrupt(struct stmmac_priv *priv)
{
        int ret;

        ret = stmmac_safety_feat_irq_status(priv, priv->dev,
                        priv->ioaddr, priv->dma_cap.asp, &priv->sstats);
        if (ret && (ret != -EINVAL)) {
                stmmac_global_err(priv);
                return true;
        }

        return false;
}

static int stmmac_napi_check(struct stmmac_priv *priv, u32 chan)
{
        int status = stmmac_dma_interrupt_status(priv, priv->ioaddr,
                                                 &priv->xstats, chan);
        struct stmmac_channel *ch = &priv->channel[chan];

        if ((status & handle_rx) && (chan < priv->plat->rx_queues_to_use)) {
                if (napi_schedule_prep(&ch->rx_napi)) {
                        stmmac_disable_dma_irq(priv, priv->ioaddr, chan);
                        __napi_schedule_irqoff(&ch->rx_napi);
                        status |= handle_tx;
                }
        }

        if ((status & handle_tx) && (chan < priv->plat->tx_queues_to_use))
                napi_schedule_irqoff(&ch->tx_napi);

        return status;
}

/**
 * stmmac_dma_interrupt - DMA ISR
 * @priv: driver private structure
 * Description: this is the DMA ISR. It is called by the main ISR.
 * It calls the dwmac dma routine and schedule poll method in case of some
 * work can be done.
 */
static void stmmac_dma_interrupt(struct stmmac_priv *priv)
{
        u32 tx_channel_count = priv->plat->tx_queues_to_use;
        u32 rx_channel_count = priv->plat->rx_queues_to_use;
        u32 channels_to_check = tx_channel_count > rx_channel_count ?
                                tx_channel_count : rx_channel_count;
        u32 chan;
        int status[max_t(u32, MTL_MAX_TX_QUEUES, MTL_MAX_RX_QUEUES)];

        /* Make sure we never check beyond our status buffer. */
        if (WARN_ON_ONCE(channels_to_check > ARRAY_SIZE(status)))
                channels_to_check = ARRAY_SIZE(status);

        for (chan = 0; chan < channels_to_check; chan++)
                status[chan] = stmmac_napi_check(priv, chan);

        for (chan = 0; chan < tx_channel_count; chan++) {
                if (unlikely(status[chan] & tx_hard_error_bump_tc)) {
                        /* Try to bump up the dma threshold on this failure */
                        if (unlikely(priv->xstats.threshold != SF_DMA_MODE) &&
                            (tc <= 256)) {
                                tc += 64;
                                if (priv->plat->force_thresh_dma_mode)
                                        stmmac_set_dma_operation_mode(priv,
                                                                      tc,
                                                                      tc,
                                                                      chan);
                                else
                                        stmmac_set_dma_operation_mode(priv,
                                                                    tc,
                                                                    SF_DMA_MODE,
                                                                    chan);
                                priv->xstats.threshold = tc;
                        }
                } else if (unlikely(status[chan] == tx_hard_error)) {
                        stmmac_tx_err(priv, chan);
                }
        }
}

/**
 * stmmac_mmc_setup: setup the Mac Management Counters (MMC)
 * @priv: driver private structure
 * Description: this masks the MMC irq, in fact, the counters are managed in SW.
 */
static void stmmac_mmc_setup(struct stmmac_priv *priv)
{
        unsigned int mode = MMC_CNTRL_RESET_ON_READ | MMC_CNTRL_COUNTER_RESET |
                            MMC_CNTRL_PRESET | MMC_CNTRL_FULL_HALF_PRESET;

        stmmac_mmc_intr_all_mask(priv, priv->mmcaddr);

        if (priv->dma_cap.rmon) {
                stmmac_mmc_ctrl(priv, priv->mmcaddr, mode);
                memset(&priv->mmc, 0, sizeof(struct stmmac_counters));
        } else
                netdev_info(priv->dev, "No MAC Management Counters available\n");
}

/**
 * stmmac_get_hw_features - get MAC capabilities from the HW cap. register.
 * @priv: driver private structure
 * Description:
 *  new GMAC chip generations have a new register to indicate the
 *  presence of the optional feature/functions.
 *  This can be also used to override the value passed through the
 *  platform and necessary for old MAC10/100 and GMAC chips.
 */
static int stmmac_get_hw_features(struct stmmac_priv *priv)
{
        return stmmac_get_hw_feature(priv, priv->ioaddr, &priv->dma_cap) == 0;
}

/**
 * stmmac_check_ether_addr - check if the MAC addr is valid
 * @priv: driver private structure
 * Description:
 * it is to verify if the MAC address is valid, in case of failures it
 * generates a random MAC address
 */
static void stmmac_check_ether_addr(struct stmmac_priv *priv)
{
        if (!is_valid_ether_addr(priv->dev->dev_addr)) {
                stmmac_get_umac_addr(priv, priv->hw, priv->dev->dev_addr, 0);
                if (!is_valid_ether_addr(priv->dev->dev_addr))
                        eth_hw_addr_random(priv->dev);
                dev_info(priv->device, "device MAC address %pM\n",
                         priv->dev->dev_addr);
        }
}

/**
 * stmmac_init_dma_engine - DMA init.
 * @priv: driver private structure
 * Description:
 * It inits the DMA invoking the specific MAC/GMAC callback.
 * Some DMA parameters can be passed from the platform;
 * in case of these are not passed a default is kept for the MAC or GMAC.
 */
static int stmmac_init_dma_engine(struct stmmac_priv *priv)
{
        u32 rx_channels_count = priv->plat->rx_queues_to_use;
        u32 tx_channels_count = priv->plat->tx_queues_to_use;
        u32 dma_csr_ch = max(rx_channels_count, tx_channels_count);
        struct stmmac_rx_queue *rx_q;
        struct stmmac_tx_queue *tx_q;
        u32 chan = 0;
        int atds = 0;
        int ret = 0;

        if (!priv->plat->dma_cfg || !priv->plat->dma_cfg->pbl) {
                dev_err(priv->device, "Invalid DMA configuration\n");
                return -EINVAL;
        }

        if (priv->extend_desc && (priv->mode == STMMAC_RING_MODE))
                atds = 1;

        ret = stmmac_reset(priv, priv->ioaddr);
        if (ret) {
                dev_err(priv->device, "Failed to reset the dma\n");
                return ret;
        }

        /* DMA Configuration */
        stmmac_dma_init(priv, priv->ioaddr, priv->plat->dma_cfg, atds);

        if (priv->plat->axi)
                stmmac_axi(priv, priv->ioaddr, priv->plat->axi);

        /* DMA CSR Channel configuration */
        for (chan = 0; chan < dma_csr_ch; chan++)
                stmmac_init_chan(priv, priv->ioaddr, priv->plat->dma_cfg, chan);

        /* DMA RX Channel Configuration */
        for (chan = 0; chan < rx_channels_count; chan++) {
                rx_q = &priv->rx_queue[chan];

                stmmac_init_rx_chan(priv, priv->ioaddr, priv->plat->dma_cfg,
                                    rx_q->dma_rx_phy, chan);

                rx_q->rx_tail_addr = rx_q->dma_rx_phy +
                            (DMA_RX_SIZE * sizeof(struct dma_desc));
                stmmac_set_rx_tail_ptr(priv, priv->ioaddr,
                                       rx_q->rx_tail_addr, chan);
        }

        /* DMA TX Channel Configuration */
        for (chan = 0; chan < tx_channels_count; chan++) {
                tx_q = &priv->tx_queue[chan];

                stmmac_init_tx_chan(priv, priv->ioaddr, priv->plat->dma_cfg,
                                    tx_q->dma_tx_phy, chan);

                tx_q->tx_tail_addr = tx_q->dma_tx_phy;
                stmmac_set_tx_tail_ptr(priv, priv->ioaddr,
                                       tx_q->tx_tail_addr, chan);
        }

        return ret;
}

static void stmmac_tx_timer_arm(struct stmmac_priv *priv, u32 queue)
{
        struct stmmac_tx_queue *tx_q = &priv->tx_queue[queue];

        mod_timer(&tx_q->txtimer, STMMAC_COAL_TIMER(priv->tx_coal_timer));
}

/**
 * stmmac_tx_timer - mitigation sw timer for tx.
 * @data: data pointer
 * Description:
 * This is the timer handler to directly invoke the stmmac_tx_clean.
 */
static void stmmac_tx_timer(struct timer_list *t)
{
        struct stmmac_tx_queue *tx_q = from_timer(tx_q, t, txtimer);
        struct stmmac_priv *priv = tx_q->priv_data;
        struct stmmac_channel *ch;

        ch = &priv->channel[tx_q->queue_index];

        /*
         * If NAPI is already running we can miss some events. Let's rearm
         * the timer and try again.
         */
        if (likely(napi_schedule_prep(&ch->tx_napi)))
                __napi_schedule(&ch->tx_napi);
        else
                mod_timer(&tx_q->txtimer, STMMAC_COAL_TIMER(10));
}

/**
 * stmmac_init_coalesce - init mitigation options.
 * @priv: driver private structure
 * Description:
 * This inits the coalesce parameters: i.e. timer rate,
 * timer handler and default threshold used for enabling the
 * interrupt on completion bit.
 */
static void stmmac_init_coalesce(struct stmmac_priv *priv)
{
        u32 tx_channel_count = priv->plat->tx_queues_to_use;
        u32 chan;

        priv->tx_coal_frames = STMMAC_TX_FRAMES;
        priv->tx_coal_timer = STMMAC_COAL_TX_TIMER;
        priv->rx_coal_frames = STMMAC_RX_FRAMES;

        for (chan = 0; chan < tx_channel_count; chan++) {
                struct stmmac_tx_queue *tx_q = &priv->tx_queue[chan];

                timer_setup(&tx_q->txtimer, stmmac_tx_timer, 0);
        }
}

static void stmmac_set_rings_length(struct stmmac_priv *priv)
{
        u32 rx_channels_count = priv->plat->rx_queues_to_use;
        u32 tx_channels_count = priv->plat->tx_queues_to_use;
        u32 chan;

        /* set TX ring length */
        for (chan = 0; chan < tx_channels_count; chan++)
                stmmac_set_tx_ring_len(priv, priv->ioaddr,
                                (DMA_TX_SIZE - 1), chan);

        /* set RX ring length */
        for (chan = 0; chan < rx_channels_count; chan++)
                stmmac_set_rx_ring_len(priv, priv->ioaddr,
                                (DMA_RX_SIZE - 1), chan);
}

/**
 *  stmmac_set_tx_queue_weight - Set TX queue weight
 *  @priv: driver private structure
 *  Description: It is used for setting TX queues weight
 */
static void stmmac_set_tx_queue_weight(struct stmmac_priv *priv)
{
        u32 tx_queues_count = priv->plat->tx_queues_to_use;
        u32 weight;
        u32 queue;

        for (queue = 0; queue < tx_queues_count; queue++) {
                weight = priv->plat->tx_queues_cfg[queue].weight;
                stmmac_set_mtl_tx_queue_weight(priv, priv->hw, weight, queue);
        }
}

/**
 *  stmmac_configure_cbs - Configure CBS in TX queue
 *  @priv: driver private structure
 *  Description: It is used for configuring CBS in AVB TX queues
 */
static void stmmac_configure_cbs(struct stmmac_priv *priv)
{
        u32 tx_queues_count = priv->plat->tx_queues_to_use;
        u32 mode_to_use;
        u32 queue;

        /* queue 0 is reserved for legacy traffic */
        for (queue = 1; queue < tx_queues_count; queue++) {
                mode_to_use = priv->plat->tx_queues_cfg[queue].mode_to_use;
                if (mode_to_use == MTL_QUEUE_DCB)
                        continue;

                stmmac_config_cbs(priv, priv->hw,
                                priv->plat->tx_queues_cfg[queue].send_slope,
                                priv->plat->tx_queues_cfg[queue].idle_slope,
                                priv->plat->tx_queues_cfg[queue].high_credit,
                                priv->plat->tx_queues_cfg[queue].low_credit,
                                queue);
        }
}

/**
 *  stmmac_rx_queue_dma_chan_map - Map RX queue to RX dma channel
 *  @priv: driver private structure
 *  Description: It is used for mapping RX queues to RX dma channels
 */
static void stmmac_rx_queue_dma_chan_map(struct stmmac_priv *priv)
{
        u32 rx_queues_count = priv->plat->rx_queues_to_use;
        u32 queue;
        u32 chan;

        for (queue = 0; queue < rx_queues_count; queue++) {
                chan = priv->plat->rx_queues_cfg[queue].chan;
                stmmac_map_mtl_to_dma(priv, priv->hw, queue, chan);
        }
}

/**
 *  stmmac_mac_config_rx_queues_prio - Configure RX Queue priority
 *  @priv: driver private structure
 *  Description: It is used for configuring the RX Queue Priority
 */
static void stmmac_mac_config_rx_queues_prio(struct stmmac_priv *priv)
{
        u32 rx_queues_count = priv->plat->rx_queues_to_use;
        u32 queue;
        u32 prio;

        for (queue = 0; queue < rx_queues_count; queue++) {
                if (!priv->plat->rx_queues_cfg[queue].use_prio)
                        continue;

                prio = priv->plat->rx_queues_cfg[queue].prio;
                stmmac_rx_queue_prio(priv, priv->hw, prio, queue);
        }
}

/**
 *  stmmac_mac_config_tx_queues_prio - Configure TX Queue priority
 *  @priv: driver private structure
 *  Description: It is used for configuring the TX Queue Priority
 */
static void stmmac_mac_config_tx_queues_prio(struct stmmac_priv *priv)
{
        u32 tx_queues_count = priv->plat->tx_queues_to_use;
        u32 queue;
        u32 prio;

        for (queue = 0; queue < tx_queues_count; queue++) {
                if (!priv->plat->tx_queues_cfg[queue].use_prio)
                        continue;

                prio = priv->plat->tx_queues_cfg[queue].prio;
                stmmac_tx_queue_prio(priv, priv->hw, prio, queue);
        }
}

/**
 *  stmmac_mac_config_rx_queues_routing - Configure RX Queue Routing
 *  @priv: driver private structure
 *  Description: It is used for configuring the RX queue routing
 */
static void stmmac_mac_config_rx_queues_routing(struct stmmac_priv *priv)
{
        u32 rx_queues_count = priv->plat->rx_queues_to_use;
        u32 queue;
        u8 packet;

        for (queue = 0; queue < rx_queues_count; queue++) {
                /* no specific packet type routing specified for the queue */
                if (priv->plat->rx_queues_cfg[queue].pkt_route == 0x0)
                        continue;

                packet = priv->plat->rx_queues_cfg[queue].pkt_route;
                stmmac_rx_queue_routing(priv, priv->hw, packet, queue);
        }
}

static void stmmac_mac_config_rss(struct stmmac_priv *priv)
{
        if (!priv->dma_cap.rssen || !priv->plat->rss_en) {
                priv->rss.enable = false;
                return;
        }

        if (priv->dev->features & NETIF_F_RXHASH)
                priv->rss.enable = true;
        else
                priv->rss.enable = false;

        stmmac_rss_configure(priv, priv->hw, &priv->rss,
                             priv->plat->rx_queues_to_use);
}

/**
 *  stmmac_mtl_configuration - Configure MTL
 *  @priv: driver private structure
 *  Description: It is used for configurring MTL
 */
static void stmmac_mtl_configuration(struct stmmac_priv *priv)
{
        u32 rx_queues_count = priv->plat->rx_queues_to_use;
        u32 tx_queues_count = priv->plat->tx_queues_to_use;

        if (tx_queues_count > 1)
                stmmac_set_tx_queue_weight(priv);

        /* Configure MTL RX algorithms */
        if (rx_queues_count > 1)
                stmmac_prog_mtl_rx_algorithms(priv, priv->hw,
                                priv->plat->rx_sched_algorithm);

        /* Configure MTL TX algorithms */
        if (tx_queues_count > 1)
                stmmac_prog_mtl_tx_algorithms(priv, priv->hw,
                                priv->plat->tx_sched_algorithm);

        /* Configure CBS in AVB TX queues */
        if (tx_queues_count > 1)
                stmmac_configure_cbs(priv);

        /* Map RX MTL to DMA channels */
        stmmac_rx_queue_dma_chan_map(priv);

        /* Enable MAC RX Queues */
        stmmac_mac_enable_rx_queues(priv);

        /* Set RX priorities */
        if (rx_queues_count > 1)
                stmmac_mac_config_rx_queues_prio(priv);

        /* Set TX priorities */
        if (tx_queues_count > 1)
                stmmac_mac_config_tx_queues_prio(priv);

        /* Set RX routing */
        if (rx_queues_count > 1)
                stmmac_mac_config_rx_queues_routing(priv);

        /* Receive Side Scaling */
        if (rx_queues_count > 1)
                stmmac_mac_config_rss(priv);
}

static void stmmac_safety_feat_configuration(struct stmmac_priv *priv)
{
        if (priv->dma_cap.asp) {
                netdev_info(priv->dev, "Enabling Safety Features\n");
                stmmac_safety_feat_config(priv, priv->ioaddr, priv->dma_cap.asp);
        } else {
                netdev_info(priv->dev, "No Safety Features support found\n");
        }
}

/**
 * stmmac_hw_setup - setup mac in a usable state.
 *  @dev : pointer to the device structure.
 *  Description:
 *  this is the main function to setup the HW in a usable state because the
 *  dma engine is reset, the core registers are configured (e.g. AXI,
 *  Checksum features, timers). The DMA is ready to start receiving and
 *  transmitting.
 *  Return value:
 *  0 on success and an appropriate (-)ve integer as defined in errno.h
 *  file on failure.
 */
static int stmmac_hw_setup(struct net_device *dev, bool init_ptp)
{
        struct stmmac_priv *priv = netdev_priv(dev);
        u32 rx_cnt = priv->plat->rx_queues_to_use;
        u32 tx_cnt = priv->plat->tx_queues_to_use;
        u32 chan;
        int ret;

        /* DMA initialization and SW reset */
        ret = stmmac_init_dma_engine(priv);
        if (ret < 0) {
                netdev_err(priv->dev, "%s: DMA engine initialization failed\n",
                           __func__);
                return ret;
        }

        /* Copy the MAC addr into the HW  */
        stmmac_set_umac_addr(priv, priv->hw, dev->dev_addr, 0);

        /* PS and related bits will be programmed according to the speed */
        if (priv->hw->pcs) {
                int speed = priv->plat->mac_port_sel_speed;

                if ((speed == SPEED_10) || (speed == SPEED_100) ||
                    (speed == SPEED_1000)) {
                        priv->hw->ps = speed;
                } else {
                        dev_warn(priv->device, "invalid port speed\n");
                        priv->hw->ps = 0;
                }
        }

        /* Initialize the MAC Core */
        stmmac_core_init(priv, priv->hw, dev);

        /* Initialize MTL*/
        stmmac_mtl_configuration(priv);

        /* Initialize Safety Features */
        stmmac_safety_feat_configuration(priv);

        ret = stmmac_rx_ipc(priv, priv->hw);
        if (!ret) {
                netdev_warn(priv->dev, "RX IPC Checksum Offload disabled\n");
                priv->plat->rx_coe = STMMAC_RX_COE_NONE;
                priv->hw->rx_csum = 0;
        }

        /* Enable the MAC Rx/Tx */
        stmmac_mac_set(priv, priv->ioaddr, true);

        /* Set the HW DMA mode and the COE */
        stmmac_dma_operation_mode(priv);

        stmmac_mmc_setup(priv);

        if (init_ptp) {
                ret = clk_prepare_enable(priv->plat->clk_ptp_ref);
                if (ret < 0)
                        netdev_warn(priv->dev, "failed to enable PTP reference clock: %d\n", ret);

                ret = stmmac_init_ptp(priv);
                if (ret == -EOPNOTSUPP)
                        netdev_warn(priv->dev, "PTP not supported by HW\n");
                else if (ret)
                        netdev_warn(priv->dev, "PTP init failed\n");
        }

        priv->tx_lpi_timer = STMMAC_DEFAULT_TWT_LS;

        if (priv->use_riwt) {
                ret = stmmac_rx_watchdog(priv, priv->ioaddr, MIN_DMA_RIWT, rx_cnt);
                if (!ret)
                        priv->rx_riwt = MIN_DMA_RIWT;
        }

        if (priv->hw->pcs)
                stmmac_pcs_ctrl_ane(priv, priv->hw, 1, priv->hw->ps, 0);

        /* set TX and RX rings length */
        stmmac_set_rings_length(priv);

        /* Enable TSO */
        if (priv->tso) {
                for (chan = 0; chan < tx_cnt; chan++)
                        stmmac_enable_tso(priv, priv->ioaddr, 1, chan);
        }

        /* Start the ball rolling... */
        stmmac_start_all_dma(priv);

        return 0;
}

static void stmmac_hw_teardown(struct net_device *dev)
{
        struct stmmac_priv *priv = netdev_priv(dev);

        clk_disable_unprepare(priv->plat->clk_ptp_ref);
}

/**
 *  stmmac_open - open entry point of the driver
 *  @dev : pointer to the device structure.
 *  Description:
 *  This function is the open entry point of the driver.
 *  Return value:
 *  0 on success and an appropriate (-)ve integer as defined in errno.h
 *  file on failure.
 */
static int stmmac_open(struct net_device *dev)
{
        struct stmmac_priv *priv = netdev_priv(dev);
        u32 chan;
        int ret;

        if (priv->hw->pcs != STMMAC_PCS_RGMII &&
            priv->hw->pcs != STMMAC_PCS_TBI &&
            priv->hw->pcs != STMMAC_PCS_RTBI) {
                ret = stmmac_init_phy(dev);
                if (ret) {
                        netdev_err(priv->dev,
                                   "%s: Cannot attach to PHY (error: %d)\n",
                                   __func__, ret);
                        return ret;
                }
        }

        /* Extra statistics */
        memset(&priv->xstats, 0, sizeof(struct stmmac_extra_stats));
        priv->xstats.threshold = tc;

        priv->dma_buf_sz = STMMAC_ALIGN(buf_sz);
        priv->rx_copybreak = STMMAC_RX_COPYBREAK;

        ret = alloc_dma_desc_resources(priv);
        if (ret < 0) {
                netdev_err(priv->dev, "%s: DMA descriptors allocation failed\n",
                           __func__);
                goto dma_desc_error;
        }

        ret = init_dma_desc_rings(dev, GFP_KERNEL);
        if (ret < 0) {
                netdev_err(priv->dev, "%s: DMA descriptors initialization failed\n",
                           __func__);
                goto init_error;
        }

        ret = stmmac_hw_setup(dev, true);
        if (ret < 0) {
                netdev_err(priv->dev, "%s: Hw setup failed\n", __func__);
                goto init_error;
        }

        stmmac_init_coalesce(priv);

        phylink_start(priv->phylink);

        /* Request the IRQ lines */
        ret = request_irq(dev->irq, stmmac_interrupt,
                          IRQF_SHARED, dev->name, dev);
        if (unlikely(ret < 0)) {
                netdev_err(priv->dev,
                           "%s: ERROR: allocating the IRQ %d (error: %d)\n",
                           __func__, dev->irq, ret);
                goto irq_error;
        }

        /* Request the Wake IRQ in case of another line is used for WoL */
        if (priv->wol_irq != dev->irq) {
                ret = request_irq(priv->wol_irq, stmmac_interrupt,
                                  IRQF_SHARED, dev->name, dev);
                if (unlikely(ret < 0)) {
                        netdev_err(priv->dev,
                                   "%s: ERROR: allocating the WoL IRQ %d (%d)\n",
                                   __func__, priv->wol_irq, ret);
                        goto wolirq_error;
                }
        }

        /* Request the IRQ lines */
        if (priv->lpi_irq > 0) {
                ret = request_irq(priv->lpi_irq, stmmac_interrupt, IRQF_SHARED,
                                  dev->name, dev);
                if (unlikely(ret < 0)) {
                        netdev_err(priv->dev,
                                   "%s: ERROR: allocating the LPI IRQ %d (%d)\n",
                                   __func__, priv->lpi_irq, ret);
                        goto lpiirq_error;
                }
        }

        stmmac_enable_all_queues(priv);
        stmmac_start_all_queues(priv);

        return 0;

lpiirq_error:
        if (priv->wol_irq != dev->irq)
                free_irq(priv->wol_irq, dev);
wolirq_error:
        free_irq(dev->irq, dev);
irq_error:
        phylink_stop(priv->phylink);

        for (chan = 0; chan < priv->plat->tx_queues_to_use; chan++)
                del_timer_sync(&priv->tx_queue[chan].txtimer);

        stmmac_hw_teardown(dev);
init_error:
        free_dma_desc_resources(priv);
dma_desc_error:
        phylink_disconnect_phy(priv->phylink);
        return ret;
}

/**
 *  stmmac_release - close entry point of the driver
 *  @dev : device pointer.
 *  Description:
 *  This is the stop entry point of the driver.
 */
static int stmmac_release(struct net_device *dev)
{
        struct stmmac_priv *priv = netdev_priv(dev);
        u32 chan;

        if (priv->eee_enabled)
                del_timer_sync(&priv->eee_ctrl_timer);

        /* Stop and disconnect the PHY */
        phylink_stop(priv->phylink);
        phylink_disconnect_phy(priv->phylink);

        stmmac_stop_all_queues(priv);

        stmmac_disable_all_queues(priv);

        for (chan = 0; chan < priv->plat->tx_queues_to_use; chan++)
                del_timer_sync(&priv->tx_queue[chan].txtimer);

        /* Free the IRQ lines */
        free_irq(dev->irq, dev);
        if (priv->wol_irq != dev->irq)
                free_irq(priv->wol_irq, dev);
        if (priv->lpi_irq > 0)
                free_irq(priv->lpi_irq, dev);

        /* Stop TX/RX DMA and clear the descriptors */
        stmmac_stop_all_dma(priv);

        /* Release and free the Rx/Tx resources */
        free_dma_desc_resources(priv);

        /* Disable the MAC Rx/Tx */
        stmmac_mac_set(priv, priv->ioaddr, false);

        netif_carrier_off(dev);

        stmmac_release_ptp(priv);

        return 0;
}

/**
 *  stmmac_tso_allocator - close entry point of the driver
 *  @priv: driver private structure
 *  @des: buffer start address
 *  @total_len: total length to fill in descriptors
 *  @last_segmant: condition for the last descriptor
 *  @queue: TX queue index
 *  Description:
 *  This function fills descriptor and request new descriptors according to
 *  buffer length to fill
 */
static void stmmac_tso_allocator(struct stmmac_priv *priv, dma_addr_t des,
                                 int total_len, bool last_segment, u32 queue)
{
        struct stmmac_tx_queue *tx_q = &priv->tx_queue[queue];
        struct dma_desc *desc;
        u32 buff_size;
        int tmp_len;

        tmp_len = total_len;

        while (tmp_len > 0) {
                dma_addr_t curr_addr;

                tx_q->cur_tx = STMMAC_GET_ENTRY(tx_q->cur_tx, DMA_TX_SIZE);
                WARN_ON(tx_q->tx_skbuff[tx_q->cur_tx]);
                desc = tx_q->dma_tx + tx_q->cur_tx;

                curr_addr = des + (total_len - tmp_len);
                if (priv->dma_cap.addr64 <= 32)
                        desc->des0 = cpu_to_le32(curr_addr);
                else
                        stmmac_set_desc_addr(priv, desc, curr_addr);

                buff_size = tmp_len >= TSO_MAX_BUFF_SIZE ?
                            TSO_MAX_BUFF_SIZE : tmp_len;

                stmmac_prepare_tso_tx_desc(priv, desc, 0, buff_size,
                                0, 1,
                                (last_segment) && (tmp_len <= TSO_MAX_BUFF_SIZE),
                                0, 0);

                tmp_len -= TSO_MAX_BUFF_SIZE;
        }
}

/**
 *  stmmac_tso_xmit - Tx entry point of the driver for oversized frames (TSO)
 *  @skb : the socket buffer
 *  @dev : device pointer
 *  Description: this is the transmit function that is called on TSO frames
 *  (support available on GMAC4 and newer chips).
 *  Diagram below show the ring programming in case of TSO frames:
 *
 *  First Descriptor
 *   --------
 *   | DES0 |---> buffer1 = L2/L3/L4 header
 *   | DES1 |---> TCP Payload (can continue on next descr...)
 *   | DES2 |---> buffer 1 and 2 len
 *   | DES3 |---> must set TSE, TCP hdr len-> [22:19]. TCP payload len [17:0]
 *   --------
 *      |
 *     ...
 *      |
 *   --------
 *   | DES0 | --| Split TCP Payload on Buffers 1 and 2
 *   | DES1 | --|
 *   | DES2 | --> buffer 1 and 2 len
 *   | DES3 |
 *   --------
 *
 * mss is fixed when enable tso, so w/o programming the TDES3 ctx field.
 */
static netdev_tx_t stmmac_tso_xmit(struct sk_buff *skb, struct net_device *dev)
{
        struct dma_desc *desc, *first, *mss_desc = NULL;
        struct stmmac_priv *priv = netdev_priv(dev);
        int nfrags = skb_shinfo(skb)->nr_frags;
        u32 queue = skb_get_queue_mapping(skb);
        unsigned int first_entry;
        struct stmmac_tx_queue *tx_q;
        int tmp_pay_len = 0;
        u32 pay_len, mss;
        u8 proto_hdr_len;
        dma_addr_t des;
        int i;

        tx_q = &priv->tx_queue[queue];

        /* Compute header lengths */
        proto_hdr_len = skb_transport_offset(skb) + tcp_hdrlen(skb);

        /* Desc availability based on threshold should be enough safe */
        if (unlikely(stmmac_tx_avail(priv, queue) <
                (((skb->len - proto_hdr_len) / TSO_MAX_BUFF_SIZE + 1)))) {
                if (!netif_tx_queue_stopped(netdev_get_tx_queue(dev, queue))) {
                        netif_tx_stop_queue(netdev_get_tx_queue(priv->dev,
                                                                queue));
                        /* This is a hard error, log it. */
                        netdev_err(priv->dev,
                                   "%s: Tx Ring full when queue awake\n",
                                   __func__);
                }
                return NETDEV_TX_BUSY;
        }

        pay_len = skb_headlen(skb) - proto_hdr_len; /* no frags */

        mss = skb_shinfo(skb)->gso_size;

        /* set new MSS value if needed */
        if (mss != tx_q->mss) {
                mss_desc = tx_q->dma_tx + tx_q->cur_tx;
                stmmac_set_mss(priv, mss_desc, mss);
                tx_q->mss = mss;
                tx_q->cur_tx = STMMAC_GET_ENTRY(tx_q->cur_tx, DMA_TX_SIZE);
                WARN_ON(tx_q->tx_skbuff[tx_q->cur_tx]);
        }

        if (netif_msg_tx_queued(priv)) {
                pr_info("%s: tcphdrlen %d, hdr_len %d, pay_len %d, mss %d\n",
                        __func__, tcp_hdrlen(skb), proto_hdr_len, pay_len, mss);
                pr_info("\tskb->len %d, skb->data_len %d\n", skb->len,
                        skb->data_len);
        }

        first_entry = tx_q->cur_tx;
        WARN_ON(tx_q->tx_skbuff[first_entry]);

        desc = tx_q->dma_tx + first_entry;
        first = desc;

        /* first descriptor: fill Headers on Buf1 */
        des = dma_map_single(priv->device, skb->data, skb_headlen(skb),
                             DMA_TO_DEVICE);
        if (dma_mapping_error(priv->device, des))
                goto dma_map_err;

        tx_q->tx_skbuff_dma[first_entry].buf = des;
        tx_q->tx_skbuff_dma[first_entry].len = skb_headlen(skb);

        if (priv->dma_cap.addr64 <= 32) {
                first->des0 = cpu_to_le32(des);

                /* Fill start of payload in buff2 of first descriptor */
                if (pay_len)
                        first->des1 = cpu_to_le32(des + proto_hdr_len);

                /* If needed take extra descriptors to fill the remaining payload */
                tmp_pay_len = pay_len - TSO_MAX_BUFF_SIZE;
        } else {
                stmmac_set_desc_addr(priv, first, des);
                tmp_pay_len = pay_len;
        }

        stmmac_tso_allocator(priv, des, tmp_pay_len, (nfrags == 0), queue);

        /* Prepare fragments */
        for (i = 0; i < nfrags; i++) {
                const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];

                des = skb_frag_dma_map(priv->device, frag, 0,
                                       skb_frag_size(frag),
                                       DMA_TO_DEVICE);
                if (dma_mapping_error(priv->device, des))
                        goto dma_map_err;

                stmmac_tso_allocator(priv, des, skb_frag_size(frag),
                                     (i == nfrags - 1), queue);

                tx_q->tx_skbuff_dma[tx_q->cur_tx].buf = des;
                tx_q->tx_skbuff_dma[tx_q->cur_tx].len = skb_frag_size(frag);
                tx_q->tx_skbuff_dma[tx_q->cur_tx].map_as_page = true;
        }

        tx_q->tx_skbuff_dma[tx_q->cur_tx].last_segment = true;

        /* Only the last descriptor gets to point to the skb. */
        tx_q->tx_skbuff[tx_q->cur_tx] = skb;

        /* We've used all descriptors we need for this skb, however,
         * advance cur_tx so that it references a fresh descriptor.
         * ndo_start_xmit will fill this descriptor the next time it's
         * called and stmmac_tx_clean may clean up to this descriptor.
         */
        tx_q->cur_tx = STMMAC_GET_ENTRY(tx_q->cur_tx, DMA_TX_SIZE);

        if (unlikely(stmmac_tx_avail(priv, queue) <= (MAX_SKB_FRAGS + 1))) {
                netif_dbg(priv, hw, priv->dev, "%s: stop transmitted packets\n",
                          __func__);
                netif_tx_stop_queue(netdev_get_tx_queue(priv->dev, queue));
        }

        dev->stats.tx_bytes += skb->len;
        priv->xstats.tx_tso_frames++;
        priv->xstats.tx_tso_nfrags += nfrags;

        /* Manage tx mitigation */
        tx_q->tx_count_frames += nfrags + 1;
        if (likely(priv->tx_coal_frames > tx_q->tx_count_frames) &&
            !(priv->synopsys_id >= DWMAC_CORE_4_00 &&
            (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) &&
            priv->hwts_tx_en)) {
                stmmac_tx_timer_arm(priv, queue);
        } else {
                tx_q->tx_count_frames = 0;
                stmmac_set_tx_ic(priv, desc);
                priv->xstats.tx_set_ic_bit++;
        }

        skb_tx_timestamp(skb);

        if (unlikely((skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) &&
                     priv->hwts_tx_en)) {
                /* declare that device is doing timestamping */
                skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
                stmmac_enable_tx_timestamp(priv, first);
        }

        /* Complete the first descriptor before granting the DMA */
        stmmac_prepare_tso_tx_desc(priv, first, 1,
                        proto_hdr_len,
                        pay_len,
                        1, tx_q->tx_skbuff_dma[first_entry].last_segment,
                        tcp_hdrlen(skb) / 4, (skb->len - proto_hdr_len));

        /* If context desc is used to change MSS */
        if (mss_desc) {
                /* Make sure that first descriptor has been completely
                 * written, including its own bit. This is because MSS is
                 * actually before first descriptor, so we need to make
                 * sure that MSS's own bit is the last thing written.
                 */
                dma_wmb();
                stmmac_set_tx_owner(priv, mss_desc);
        }

        /* The own bit must be the latest setting done when prepare the
         * descriptor and then barrier is needed to make sure that
         * all is coherent before granting the DMA engine.
         */
        wmb();

        if (netif_msg_pktdata(priv)) {
                pr_info("%s: curr=%d dirty=%d f=%d, e=%d, f_p=%p, nfrags %d\n",
                        __func__, tx_q->cur_tx, tx_q->dirty_tx, first_entry,
                        tx_q->cur_tx, first, nfrags);

                stmmac_display_ring(priv, (void *)tx_q->dma_tx, DMA_TX_SIZE, 0);

                pr_info(">>> frame to be transmitted: ");
                print_pkt(skb->data, skb_headlen(skb));
        }

        netdev_tx_sent_queue(netdev_get_tx_queue(dev, queue), skb->len);

        tx_q->tx_tail_addr = tx_q->dma_tx_phy + (tx_q->cur_tx * sizeof(*desc));
        stmmac_set_tx_tail_ptr(priv, priv->ioaddr, tx_q->tx_tail_addr, queue);

        return NETDEV_TX_OK;

dma_map_err:
        dev_err(priv->device, "Tx dma map failed\n");
        dev_kfree_skb(skb);
        priv->dev->stats.tx_dropped++;
        return NETDEV_TX_OK;
}

/**
 *  stmmac_xmit - Tx entry point of the driver
 *  @skb : the socket buffer
 *  @dev : device pointer
 *  Description : this is the tx entry point of the driver.
 *  It programs the chain or the ring and supports oversized frames
 *  and SG feature.
 */
static netdev_tx_t stmmac_xmit(struct sk_buff *skb, struct net_device *dev)
{
        struct stmmac_priv *priv = netdev_priv(dev);
        unsigned int nopaged_len = skb_headlen(skb);
        int i, csum_insertion = 0, is_jumbo = 0;
        u32 queue = skb_get_queue_mapping(skb);
        int nfrags = skb_shinfo(skb)->nr_frags;
        struct dma_desc *desc, *first;
        struct stmmac_tx_queue *tx_q;
        unsigned int first_entry;
        unsigned int enh_desc;
        dma_addr_t des;
        int entry;

        tx_q = &priv->tx_queue[queue];

        if (priv->tx_path_in_lpi_mode)
                stmmac_disable_eee_mode(priv);

        /* Manage oversized TCP frames for GMAC4 device */
        if (skb_is_gso(skb) && priv->tso) {
                if (skb_shinfo(skb)->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6))
                        return stmmac_tso_xmit(skb, dev);
        }

        if (unlikely(stmmac_tx_avail(priv, queue) < nfrags + 1)) {
                if (!netif_tx_queue_stopped(netdev_get_tx_queue(dev, queue))) {
                        netif_tx_stop_queue(netdev_get_tx_queue(priv->dev,
                                                                queue));
                        /* This is a hard error, log it. */
                        netdev_err(priv->dev,
                                   "%s: Tx Ring full when queue awake\n",
                                   __func__);
                }
                return NETDEV_TX_BUSY;
        }

        entry = tx_q->cur_tx;
        first_entry = entry;
        WARN_ON(tx_q->tx_skbuff[first_entry]);

        csum_insertion = (skb->ip_summed == CHECKSUM_PARTIAL);

        if (likely(priv->extend_desc))
                desc = (struct dma_desc *)(tx_q->dma_etx + entry);
        else
                desc = tx_q->dma_tx + entry;

        first = desc;

        enh_desc = priv->plat->enh_desc;
        /* To program the descriptors according to the size of the frame */
        if (enh_desc)
                is_jumbo = stmmac_is_jumbo_frm(priv, skb->len, enh_desc);

        if (unlikely(is_jumbo)) {
                entry = stmmac_jumbo_frm(priv, tx_q, skb, csum_insertion);
                if (unlikely(entry < 0) && (entry != -EINVAL))
                        goto dma_map_err;
        }

        for (i = 0; i < nfrags; i++) {
                const skb_frag_t *frag = &skb_shinfo(skb)->frags[i];
                int len = skb_frag_size(frag);
                bool last_segment = (i == (nfrags - 1));

                entry = STMMAC_GET_ENTRY(entry, DMA_TX_SIZE);
                WARN_ON(tx_q->tx_skbuff[entry]);

                if (likely(priv->extend_desc))
                        desc = (struct dma_desc *)(tx_q->dma_etx + entry);
                else
                        desc = tx_q->dma_tx + entry;

                des = skb_frag_dma_map(priv->device, frag, 0, len,
                                       DMA_TO_DEVICE);
                if (dma_mapping_error(priv->device, des))
                        goto dma_map_err; /* should reuse desc w/o issues */

                tx_q->tx_skbuff_dma[entry].buf = des;

                stmmac_set_desc_addr(priv, desc, des);

                tx_q->tx_skbuff_dma[entry].map_as_page = true;
                tx_q->tx_skbuff_dma[entry].len = len;
                tx_q->tx_skbuff_dma[entry].last_segment = last_segment;

                /* Prepare the descriptor and set the own bit too */
                stmmac_prepare_tx_desc(priv, desc, 0, len, csum_insertion,
                                priv->mode, 1, last_segment, skb->len);
        }

        /* Only the last descriptor gets to point to the skb. */
        tx_q->tx_skbuff[entry] = skb;

        /* We've used all descriptors we need for this skb, however,
         * advance cur_tx so that it references a fresh descriptor.
         * ndo_start_xmit will fill this descriptor the next time it's
         * called and stmmac_tx_clean may clean up to this descriptor.
         */
        entry = STMMAC_GET_ENTRY(entry, DMA_TX_SIZE);
        tx_q->cur_tx = entry;

        if (netif_msg_pktdata(priv)) {
                void *tx_head;

                netdev_dbg(priv->dev,
                           "%s: curr=%d dirty=%d f=%d, e=%d, first=%p, nfrags=%d",
                           __func__, tx_q->cur_tx, tx_q->dirty_tx, first_entry,
                           entry, first, nfrags);

                if (priv->extend_desc)
                        tx_head = (void *)tx_q->dma_etx;
                else
                        tx_head = (void *)tx_q->dma_tx;

                stmmac_display_ring(priv, tx_head, DMA_TX_SIZE, false);

                netdev_dbg(priv->dev, ">>> frame to be transmitted: ");
                print_pkt(skb->data, skb->len);
        }

        if (unlikely(stmmac_tx_avail(priv, queue) <= (MAX_SKB_FRAGS + 1))) {
                netif_dbg(priv, hw, priv->dev, "%s: stop transmitted packets\n",
                          __func__);
                netif_tx_stop_queue(netdev_get_tx_queue(priv->dev, queue));
        }

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

        /* According to the coalesce parameter the IC bit for the latest
         * segment is reset and the timer re-started to clean the tx status.
         * This approach takes care about the fragments: desc is the first
         * element in case of no SG.
         */
        tx_q->tx_count_frames += nfrags + 1;
        if (likely(priv->tx_coal_frames > tx_q->tx_count_frames) &&
            !(priv->synopsys_id >= DWMAC_CORE_4_00 &&
            (skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) &&
            priv->hwts_tx_en)) {
                stmmac_tx_timer_arm(priv, queue);
        } else {
                tx_q->tx_count_frames = 0;
                stmmac_set_tx_ic(priv, desc);
                priv->xstats.tx_set_ic_bit++;
        }

        skb_tx_timestamp(skb);

        /* Ready to fill the first descriptor and set the OWN bit w/o any
         * problems because all the descriptors are actually ready to be
         * passed to the DMA engine.
         */
        if (likely(!is_jumbo)) {
                bool last_segment = (nfrags == 0);

                des = dma_map_single(priv->device, skb->data,
                                     nopaged_len, DMA_TO_DEVICE);
                if (dma_mapping_error(priv->device, des))
                        goto dma_map_err;

                tx_q->tx_skbuff_dma[first_entry].buf = des;

                stmmac_set_desc_addr(priv, first, des);

                tx_q->tx_skbuff_dma[first_entry].len = nopaged_len;
                tx_q->tx_skbuff_dma[first_entry].last_segment = last_segment;

                if (unlikely((skb_shinfo(skb)->tx_flags & SKBTX_HW_TSTAMP) &&
                             priv->hwts_tx_en)) {
                        /* declare that device is doing timestamping */
                        skb_shinfo(skb)->tx_flags |= SKBTX_IN_PROGRESS;
                        stmmac_enable_tx_timestamp(priv, first);
                }

                /* Prepare the first descriptor setting the OWN bit too */
                stmmac_prepare_tx_desc(priv, first, 1, nopaged_len,
                                csum_insertion, priv->mode, 1, last_segment,
                                skb->len);
        } else {
                stmmac_set_tx_owner(priv, first);
        }

        /* The own bit must be the latest setting done when prepare the
         * descriptor and then barrier is needed to make sure that
         * all is coherent before granting the DMA engine.
         */
        wmb();

        netdev_tx_sent_queue(netdev_get_tx_queue(dev, queue), skb->len);

        stmmac_enable_dma_transmission(priv, priv->ioaddr);

        tx_q->tx_tail_addr = tx_q->dma_tx_phy + (tx_q->cur_tx * sizeof(*desc));
        stmmac_set_tx_tail_ptr(priv, priv->ioaddr, tx_q->tx_tail_addr, queue);

        return NETDEV_TX_OK;

dma_map_err:
        netdev_err(priv->dev, "Tx DMA map failed\n");
        dev_kfree_skb(skb);
        priv->dev->stats.tx_dropped++;
        return NETDEV_TX_OK;
}

static void stmmac_rx_vlan(struct net_device *dev, struct sk_buff *skb)
{
        struct vlan_ethhdr *veth;
        __be16 vlan_proto;
        u16 vlanid;

        veth = (struct vlan_ethhdr *)skb->data;
        vlan_proto = veth->h_vlan_proto;

        if ((vlan_proto == htons(ETH_P_8021Q) &&
             dev->features & NETIF_F_HW_VLAN_CTAG_RX) ||
            (vlan_proto == htons(ETH_P_8021AD) &&
             dev->features & NETIF_F_HW_VLAN_STAG_RX)) {
                /* pop the vlan tag */
                vlanid = ntohs(veth->h_vlan_TCI);
                memmove(skb->data + VLAN_HLEN, veth, ETH_ALEN * 2);
                skb_pull(skb, VLAN_HLEN);
                __vlan_hwaccel_put_tag(skb, vlan_proto, vlanid);
        }
}


static inline int stmmac_rx_threshold_count(struct stmmac_rx_queue *rx_q)
{
        if (rx_q->rx_zeroc_thresh < STMMAC_RX_THRESH)
                return 0;

        return 1;
}

/**
 * stmmac_rx_refill - refill used skb preallocated buffers
 * @priv: driver private structure
 * @queue: RX queue index
 * Description : this is to reallocate the skb for the reception process
 * that is based on zero-copy.
 */
static inline void stmmac_rx_refill(struct stmmac_priv *priv, u32 queue)
{
        struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];
        int len, dirty = stmmac_rx_dirty(priv, queue);
        unsigned int entry = rx_q->dirty_rx;

        len = DIV_ROUND_UP(priv->dma_buf_sz, PAGE_SIZE) * PAGE_SIZE;

        while (dirty-- > 0) {
                struct stmmac_rx_buffer *buf = &rx_q->buf_pool[entry];
                struct dma_desc *p;
                bool use_rx_wd;

                if (priv->extend_desc)
                        p = (struct dma_desc *)(rx_q->dma_erx + entry);
                else
                        p = rx_q->dma_rx + entry;

                if (!buf->page) {
                        buf->page = page_pool_dev_alloc_pages(rx_q->page_pool);
                        if (!buf->page)
                                break;
                }

                buf->addr = page_pool_get_dma_addr(buf->page);

                /* Sync whole allocation to device. This will invalidate old
                 * data.
                 */
                dma_sync_single_for_device(priv->device, buf->addr, len,
                                           DMA_FROM_DEVICE);

                stmmac_set_desc_addr(priv, p, buf->addr);
                stmmac_refill_desc3(priv, rx_q, p);

                rx_q->rx_count_frames++;
                rx_q->rx_count_frames %= priv->rx_coal_frames;
                use_rx_wd = priv->use_riwt && rx_q->rx_count_frames;

                dma_wmb();
                stmmac_set_rx_owner(priv, p, use_rx_wd);

                entry = STMMAC_GET_ENTRY(entry, DMA_RX_SIZE);
        }
        rx_q->dirty_rx = entry;
        rx_q->rx_tail_addr = rx_q->dma_rx_phy +
                            (rx_q->dirty_rx * sizeof(struct dma_desc));
        stmmac_set_rx_tail_ptr(priv, priv->ioaddr, rx_q->rx_tail_addr, queue);
}

/**
 * stmmac_rx - manage the receive process
 * @priv: driver private structure
 * @limit: napi bugget
 * @queue: RX queue index.
 * Description :  this the function called by the napi poll method.
 * It gets all the frames inside the ring.
 */
static int stmmac_rx(struct stmmac_priv *priv, int limit, u32 queue)
{
        struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];
        struct stmmac_channel *ch = &priv->channel[queue];
        unsigned int next_entry = rx_q->cur_rx;
        int coe = priv->hw->rx_csum;
        unsigned int count = 0;

        if (netif_msg_rx_status(priv)) {
                void *rx_head;

                netdev_dbg(priv->dev, "%s: descriptor ring:\n", __func__);
                if (priv->extend_desc)
                        rx_head = (void *)rx_q->dma_erx;
                else
                        rx_head = (void *)rx_q->dma_rx;

                stmmac_display_ring(priv, rx_head, DMA_RX_SIZE, true);
        }
        while (count < limit) {
                struct stmmac_rx_buffer *buf;
                struct dma_desc *np, *p;
                int entry, status;

                entry = next_entry;
                buf = &rx_q->buf_pool[entry];

                if (priv->extend_desc)
                        p = (struct dma_desc *)(rx_q->dma_erx + entry);
                else
                        p = rx_q->dma_rx + entry;

                /* read the status of the incoming frame */
                status = stmmac_rx_status(priv, &priv->dev->stats,
                                &priv->xstats, p);
                /* check if managed by the DMA otherwise go ahead */
                if (unlikely(status & dma_own))
                        break;

                count++;

                rx_q->cur_rx = STMMAC_GET_ENTRY(rx_q->cur_rx, DMA_RX_SIZE);
                next_entry = rx_q->cur_rx;

                if (priv->extend_desc)
                        np = (struct dma_desc *)(rx_q->dma_erx + next_entry);
                else
                        np = rx_q->dma_rx + next_entry;

                prefetch(np);

                if (priv->extend_desc)
                        stmmac_rx_extended_status(priv, &priv->dev->stats,
                                        &priv->xstats, rx_q->dma_erx + entry);
                if (unlikely(status == discard_frame)) {
                        page_pool_recycle_direct(rx_q->page_pool, buf->page);
                        priv->dev->stats.rx_errors++;
                        buf->page = NULL;
                } else {
                        enum pkt_hash_types hash_type;
                        struct sk_buff *skb;
                        unsigned int des;
                        int frame_len;
                        u32 hash;

                        stmmac_get_desc_addr(priv, p, &des);
                        frame_len = stmmac_get_rx_frame_len(priv, p, coe);

                        /*  If frame length is greater than skb buffer size
                         *  (preallocated during init) then the packet is
                         *  ignored
                         */
                        if (frame_len > priv->dma_buf_sz) {
                                if (net_ratelimit())
                                        netdev_err(priv->dev,
                                                   "len %d larger than size (%d)\n",
                                                   frame_len, priv->dma_buf_sz);
                                priv->dev->stats.rx_length_errors++;
                                continue;
                        }

                        /* ACS is set; GMAC core strips PAD/FCS for IEEE 802.3
                         * Type frames (LLC/LLC-SNAP)
                         *
                         * llc_snap is never checked in GMAC >= 4, so this ACS
                         * feature is always disabled and packets need to be
                         * stripped manually.
                         */
                        if (unlikely(priv->synopsys_id >= DWMAC_CORE_4_00) ||
                            unlikely(status != llc_snap))
                                frame_len -= ETH_FCS_LEN;

                        if (netif_msg_rx_status(priv)) {
                                netdev_dbg(priv->dev, "\tdesc: %p [entry %d] buff=0x%x\n",
                                           p, entry, des);
                                netdev_dbg(priv->dev, "frame size %d, COE: %d\n",
                                           frame_len, status);
                        }

                        skb = netdev_alloc_skb_ip_align(priv->dev, frame_len);
                        if (unlikely(!skb)) {
                                priv->dev->stats.rx_dropped++;
                                continue;
                        }

                        dma_sync_single_for_cpu(priv->device, buf->addr,
                                                frame_len, DMA_FROM_DEVICE);
                        skb_copy_to_linear_data(skb, page_address(buf->page),
                                                frame_len);
                        skb_put(skb, frame_len);

                        if (netif_msg_pktdata(priv)) {
                                netdev_dbg(priv->dev, "frame received (%dbytes)",
                                           frame_len);
                                print_pkt(skb->data, frame_len);
                        }

                        stmmac_get_rx_hwtstamp(priv, p, np, skb);

                        stmmac_rx_vlan(priv->dev, skb);

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

                        if (unlikely(!coe))
                                skb_checksum_none_assert(skb);
                        else
                                skb->ip_summed = CHECKSUM_UNNECESSARY;

                        if (!stmmac_get_rx_hash(priv, p, &hash, &hash_type))
                                skb_set_hash(skb, hash, hash_type);

                        skb_record_rx_queue(skb, queue);
                        napi_gro_receive(&ch->rx_napi, skb);

                        /* Data payload copied into SKB, page ready for recycle */
                        page_pool_recycle_direct(rx_q->page_pool, buf->page);
                        buf->page = NULL;

                        priv->dev->stats.rx_packets++;
                        priv->dev->stats.rx_bytes += frame_len;
                }
        }

        stmmac_rx_refill(priv, queue);

        priv->xstats.rx_pkt_n += count;

        return count;
}

static int stmmac_napi_poll_rx(struct napi_struct *napi, int budget)
{
        struct stmmac_channel *ch =
                container_of(napi, struct stmmac_channel, rx_napi);
        struct stmmac_priv *priv = ch->priv_data;
        u32 chan = ch->index;
        int work_done;

        priv->xstats.napi_poll++;

        work_done = stmmac_rx(priv, budget, chan);
        if (work_done < budget && napi_complete_done(napi, work_done))
                stmmac_enable_dma_irq(priv, priv->ioaddr, chan);
        return work_done;
}

static int stmmac_napi_poll_tx(struct napi_struct *napi, int budget)
{
        struct stmmac_channel *ch =
                container_of(napi, struct stmmac_channel, tx_napi);
        struct stmmac_priv *priv = ch->priv_data;
        struct stmmac_tx_queue *tx_q;
        u32 chan = ch->index;
        int work_done;

        priv->xstats.napi_poll++;

        work_done = stmmac_tx_clean(priv, DMA_TX_SIZE, chan);
        work_done = min(work_done, budget);

        if (work_done < budget)
                napi_complete_done(napi, work_done);

        /* Force transmission restart */
        tx_q = &priv->tx_queue[chan];
        if (tx_q->cur_tx != tx_q->dirty_tx) {
                stmmac_enable_dma_transmission(priv, priv->ioaddr);
                stmmac_set_tx_tail_ptr(priv, priv->ioaddr, tx_q->tx_tail_addr,
                                       chan);
        }

        return work_done;
}

/**
 *  stmmac_tx_timeout
 *  @dev : Pointer to net device structure
 *  Description: this function is called when a packet transmission fails to
 *   complete within a reasonable time. The driver will mark the error in the
 *   netdev structure and arrange for the device to be reset to a sane state
 *   in order to transmit a new packet.
 */
static void stmmac_tx_timeout(struct net_device *dev)
{
        struct stmmac_priv *priv = netdev_priv(dev);

        stmmac_global_err(priv);
}

/**
 *  stmmac_set_rx_mode - entry point for multicast addressing
 *  @dev : pointer to the device structure
 *  Description:
 *  This function is a driver entry point which gets called by the kernel
 *  whenever multicast addresses must be enabled/disabled.
 *  Return value:
 *  void.
 */
static void stmmac_set_rx_mode(struct net_device *dev)
{
        struct stmmac_priv *priv = netdev_priv(dev);

        stmmac_set_filter(priv, priv->hw, dev);
}

/**
 *  stmmac_change_mtu - entry point to change MTU size for the device.
 *  @dev : device pointer.
 *  @new_mtu : the new MTU size for the device.
 *  Description: the Maximum Transfer Unit (MTU) is used by the network layer
 *  to drive packet transmission. Ethernet has an MTU of 1500 octets
 *  (ETH_DATA_LEN). This value can be changed with ifconfig.
 *  Return value:
 *  0 on success and an appropriate (-)ve integer as defined in errno.h
 *  file on failure.
 */
static int stmmac_change_mtu(struct net_device *dev, int new_mtu)
{
        struct stmmac_priv *priv = netdev_priv(dev);

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

        dev->mtu = new_mtu;

        netdev_update_features(dev);

        return 0;
}

static netdev_features_t stmmac_fix_features(struct net_device *dev,
                                             netdev_features_t features)
{
        struct stmmac_priv *priv = netdev_priv(dev);

        if (priv->plat->rx_coe == STMMAC_RX_COE_NONE)
                features &= ~NETIF_F_RXCSUM;

        if (!priv->plat->tx_coe)
                features &= ~NETIF_F_CSUM_MASK;

        /* Some GMAC devices have a bugged Jumbo frame support that
         * needs to have the Tx COE disabled for oversized frames
         * (due to limited buffer sizes). In this case we disable
         * the TX csum insertion in the TDES and not use SF.
         */
        if (priv->plat->bugged_jumbo && (dev->mtu > ETH_DATA_LEN))
                features &= ~NETIF_F_CSUM_MASK;

        /* Disable tso if asked by ethtool */
        if ((priv->plat->tso_en) && (priv->dma_cap.tsoen)) {
                if (features & NETIF_F_TSO)
                        priv->tso = true;
                else
                        priv->tso = false;
        }

        return features;
}

static int stmmac_set_features(struct net_device *netdev,
                               netdev_features_t features)
{
        struct stmmac_priv *priv = netdev_priv(netdev);

        /* Keep the COE Type in case of csum is supporting */
        if (features & NETIF_F_RXCSUM)
                priv->hw->rx_csum = priv->plat->rx_coe;
        else
                priv->hw->rx_csum = 0;
        /* No check needed because rx_coe has been set before and it will be
         * fixed in case of issue.
         */
        stmmac_rx_ipc(priv, priv->hw);

        return 0;
}

/**
 *  stmmac_interrupt - main ISR
 *  @irq: interrupt number.
 *  @dev_id: to pass the net device pointer.
 *  Description: this is the main driver interrupt service routine.
 *  It can call:
 *  o DMA service routine (to manage incoming frame reception and transmission
 *    status)
 *  o Core interrupts to manage: remote wake-up, management counter, LPI
 *    interrupts.
 */
static irqreturn_t stmmac_interrupt(int irq, void *dev_id)
{
        struct net_device *dev = (struct net_device *)dev_id;
        struct stmmac_priv *priv = netdev_priv(dev);
        u32 rx_cnt = priv->plat->rx_queues_to_use;
        u32 tx_cnt = priv->plat->tx_queues_to_use;
        u32 queues_count;
        u32 queue;
        bool xmac;

        xmac = priv->plat->has_gmac4 || priv->plat->has_xgmac;
        queues_count = (rx_cnt > tx_cnt) ? rx_cnt : tx_cnt;

        if (priv->irq_wake)
                pm_wakeup_event(priv->device, 0);

        if (unlikely(!dev)) {
                netdev_err(priv->dev, "%s: invalid dev pointer\n", __func__);
                return IRQ_NONE;
        }

        /* Check if adapter is up */
        if (test_bit(STMMAC_DOWN, &priv->state))
                return IRQ_HANDLED;
        /* Check if a fatal error happened */
        if (stmmac_safety_feat_interrupt(priv))
                return IRQ_HANDLED;

        /* To handle GMAC own interrupts */
        if ((priv->plat->has_gmac) || xmac) {
                int status = stmmac_host_irq_status(priv, priv->hw, &priv->xstats);
                int mtl_status;

                if (unlikely(status)) {
                        /* For LPI we need to save the tx status */
                        if (status & CORE_IRQ_TX_PATH_IN_LPI_MODE)
                                priv->tx_path_in_lpi_mode = true;
                        if (status & CORE_IRQ_TX_PATH_EXIT_LPI_MODE)
                                priv->tx_path_in_lpi_mode = false;
                }

                for (queue = 0; queue < queues_count; queue++) {
                        struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];

                        mtl_status = stmmac_host_mtl_irq_status(priv, priv->hw,
                                                                queue);
                        if (mtl_status != -EINVAL)
                                status |= mtl_status;

                        if (status & CORE_IRQ_MTL_RX_OVERFLOW)
                                stmmac_set_rx_tail_ptr(priv, priv->ioaddr,
                                                       rx_q->rx_tail_addr,
                                                       queue);
                }

                /* PCS link status */
                if (priv->hw->pcs) {
                        if (priv->xstats.pcs_link)
                                netif_carrier_on(dev);
                        else
                                netif_carrier_off(dev);
                }
        }

        /* To handle DMA interrupts */
        stmmac_dma_interrupt(priv);

        return IRQ_HANDLED;
}

#ifdef CONFIG_NET_POLL_CONTROLLER
/* Polling receive - used by NETCONSOLE and other diagnostic tools
 * to allow network I/O with interrupts disabled.
 */
static void stmmac_poll_controller(struct net_device *dev)
{
        disable_irq(dev->irq);
        stmmac_interrupt(dev->irq, dev);
        enable_irq(dev->irq);
}
#endif

/**
 *  stmmac_ioctl - Entry point for the Ioctl
 *  @dev: Device pointer.
 *  @rq: An IOCTL specefic structure, that can contain a pointer to
 *  a proprietary structure used to pass information to the driver.
 *  @cmd: IOCTL command
 *  Description:
 *  Currently it supports the phy_mii_ioctl(...) and HW time stamping.
 */
static int stmmac_ioctl(struct net_device *dev, struct ifreq *rq, int cmd)
{
        struct stmmac_priv *priv = netdev_priv (dev);
        int ret = -EOPNOTSUPP;

        if (!netif_running(dev))
                return -EINVAL;

        switch (cmd) {
        case SIOCGMIIPHY:
        case SIOCGMIIREG:
        case SIOCSMIIREG:
                ret = phylink_mii_ioctl(priv->phylink, rq, cmd);
                break;
        case SIOCSHWTSTAMP:
                ret = stmmac_hwtstamp_set(dev, rq);
                break;
        case SIOCGHWTSTAMP:
                ret = stmmac_hwtstamp_get(dev, rq);
                break;
        default:
                break;
        }

        return ret;
}

static int stmmac_setup_tc_block_cb(enum tc_setup_type type, void *type_data,
                                    void *cb_priv)
{
        struct stmmac_priv *priv = cb_priv;
        int ret = -EOPNOTSUPP;

        stmmac_disable_all_queues(priv);

        switch (type) {
        case TC_SETUP_CLSU32:
                if (tc_cls_can_offload_and_chain0(priv->dev, type_data))
                        ret = stmmac_tc_setup_cls_u32(priv, priv, type_data);
                break;
        default:
                break;
        }

        stmmac_enable_all_queues(priv);
        return ret;
}

static LIST_HEAD(stmmac_block_cb_list);

static int stmmac_setup_tc(struct net_device *ndev, enum tc_setup_type type,
                           void *type_data)
{
        struct stmmac_priv *priv = netdev_priv(ndev);

        switch (type) {
        case TC_SETUP_BLOCK:
                return flow_block_cb_setup_simple(type_data,
                                                  &stmmac_block_cb_list,
                                                  stmmac_setup_tc_block_cb,
                                                  priv, priv, true);
        case TC_SETUP_QDISC_CBS:
                return stmmac_tc_setup_cbs(priv, priv, type_data);
        default:
                return -EOPNOTSUPP;
        }
}

static u16 stmmac_select_queue(struct net_device *dev, struct sk_buff *skb,
                               struct net_device *sb_dev)
{
        if (skb_shinfo(skb)->gso_type & (SKB_GSO_TCPV4 | SKB_GSO_TCPV6)) {
                /*
                 * There is no way to determine the number of TSO
                 * capable Queues. Let's use always the Queue 0
                 * because if TSO is supported then at least this
                 * one will be capable.
                 */
                return 0;
        }

        return netdev_pick_tx(dev, skb, NULL) % dev->real_num_tx_queues;
}

static int stmmac_set_mac_address(struct net_device *ndev, void *addr)
{
        struct stmmac_priv *priv = netdev_priv(ndev);
        int ret = 0;

        ret = eth_mac_addr(ndev, addr);
        if (ret)
                return ret;

        stmmac_set_umac_addr(priv, priv->hw, ndev->dev_addr, 0);

        return ret;
}

#ifdef CONFIG_DEBUG_FS
static struct dentry *stmmac_fs_dir;

static void sysfs_display_ring(void *head, int size, int extend_desc,
                               struct seq_file *seq)
{
        int i;
        struct dma_extended_desc *ep = (struct dma_extended_desc *)head;
        struct dma_desc *p = (struct dma_desc *)head;

        for (i = 0; i < size; i++) {
                if (extend_desc) {
                        seq_printf(seq, "%d [0x%x]: 0x%x 0x%x 0x%x 0x%x\n",
                                   i, (unsigned int)virt_to_phys(ep),
                                   le32_to_cpu(ep->basic.des0),
                                   le32_to_cpu(ep->basic.des1),
                                   le32_to_cpu(ep->basic.des2),
                                   le32_to_cpu(ep->basic.des3));
                        ep++;
                } else {
                        seq_printf(seq, "%d [0x%x]: 0x%x 0x%x 0x%x 0x%x\n",
                                   i, (unsigned int)virt_to_phys(p),
                                   le32_to_cpu(p->des0), le32_to_cpu(p->des1),
                                   le32_to_cpu(p->des2), le32_to_cpu(p->des3));
                        p++;
                }
                seq_printf(seq, "\n");
        }
}

static int stmmac_rings_status_show(struct seq_file *seq, void *v)
{
        struct net_device *dev = seq->private;
        struct stmmac_priv *priv = netdev_priv(dev);
        u32 rx_count = priv->plat->rx_queues_to_use;
        u32 tx_count = priv->plat->tx_queues_to_use;
        u32 queue;

        if ((dev->flags & IFF_UP) == 0)
                return 0;

        for (queue = 0; queue < rx_count; queue++) {
                struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];

                seq_printf(seq, "RX Queue %d:\n", queue);

                if (priv->extend_desc) {
                        seq_printf(seq, "Extended descriptor ring:\n");
                        sysfs_display_ring((void *)rx_q->dma_erx,
                                           DMA_RX_SIZE, 1, seq);
                } else {
                        seq_printf(seq, "Descriptor ring:\n");
                        sysfs_display_ring((void *)rx_q->dma_rx,
                                           DMA_RX_SIZE, 0, seq);
                }
        }

        for (queue = 0; queue < tx_count; queue++) {
                struct stmmac_tx_queue *tx_q = &priv->tx_queue[queue];

                seq_printf(seq, "TX Queue %d:\n", queue);

                if (priv->extend_desc) {
                        seq_printf(seq, "Extended descriptor ring:\n");
                        sysfs_display_ring((void *)tx_q->dma_etx,
                                           DMA_TX_SIZE, 1, seq);
                } else {
                        seq_printf(seq, "Descriptor ring:\n");
                        sysfs_display_ring((void *)tx_q->dma_tx,
                                           DMA_TX_SIZE, 0, seq);
                }
        }

        return 0;
}
DEFINE_SHOW_ATTRIBUTE(stmmac_rings_status);

static int stmmac_dma_cap_show(struct seq_file *seq, void *v)
{
        struct net_device *dev = seq->private;
        struct stmmac_priv *priv = netdev_priv(dev);

        if (!priv->hw_cap_support) {
                seq_printf(seq, "DMA HW features not supported\n");
                return 0;
        }

        seq_printf(seq, "==============================\n");
        seq_printf(seq, "\tDMA HW features\n");
        seq_printf(seq, "==============================\n");

        seq_printf(seq, "\t10/100 Mbps: %s\n",
                   (priv->dma_cap.mbps_10_100) ? "Y" : "N");
        seq_printf(seq, "\t1000 Mbps: %s\n",
                   (priv->dma_cap.mbps_1000) ? "Y" : "N");
        seq_printf(seq, "\tHalf duplex: %s\n",
                   (priv->dma_cap.half_duplex) ? "Y" : "N");
        seq_printf(seq, "\tHash Filter: %s\n",
                   (priv->dma_cap.hash_filter) ? "Y" : "N");
        seq_printf(seq, "\tMultiple MAC address registers: %s\n",
                   (priv->dma_cap.multi_addr) ? "Y" : "N");
        seq_printf(seq, "\tPCS (TBI/SGMII/RTBI PHY interfaces): %s\n",
                   (priv->dma_cap.pcs) ? "Y" : "N");
        seq_printf(seq, "\tSMA (MDIO) Interface: %s\n",
                   (priv->dma_cap.sma_mdio) ? "Y" : "N");
        seq_printf(seq, "\tPMT Remote wake up: %s\n",
                   (priv->dma_cap.pmt_remote_wake_up) ? "Y" : "N");
        seq_printf(seq, "\tPMT Magic Frame: %s\n",
                   (priv->dma_cap.pmt_magic_frame) ? "Y" : "N");
        seq_printf(seq, "\tRMON module: %s\n",
                   (priv->dma_cap.rmon) ? "Y" : "N");
        seq_printf(seq, "\tIEEE 1588-2002 Time Stamp: %s\n",
                   (priv->dma_cap.time_stamp) ? "Y" : "N");
        seq_printf(seq, "\tIEEE 1588-2008 Advanced Time Stamp: %s\n",
                   (priv->dma_cap.atime_stamp) ? "Y" : "N");
        seq_printf(seq, "\t802.3az - Energy-Efficient Ethernet (EEE): %s\n",
                   (priv->dma_cap.eee) ? "Y" : "N");
        seq_printf(seq, "\tAV features: %s\n", (priv->dma_cap.av) ? "Y" : "N");
        seq_printf(seq, "\tChecksum Offload in TX: %s\n",
                   (priv->dma_cap.tx_coe) ? "Y" : "N");
        if (priv->synopsys_id >= DWMAC_CORE_4_00) {
                seq_printf(seq, "\tIP Checksum Offload in RX: %s\n",
                           (priv->dma_cap.rx_coe) ? "Y" : "N");
        } else {
                seq_printf(seq, "\tIP Checksum Offload (type1) in RX: %s\n",
                           (priv->dma_cap.rx_coe_type1) ? "Y" : "N");
                seq_printf(seq, "\tIP Checksum Offload (type2) in RX: %s\n",
                           (priv->dma_cap.rx_coe_type2) ? "Y" : "N");
        }
        seq_printf(seq, "\tRXFIFO > 2048bytes: %s\n",
                   (priv->dma_cap.rxfifo_over_2048) ? "Y" : "N");
        seq_printf(seq, "\tNumber of Additional RX channel: %d\n",
                   priv->dma_cap.number_rx_channel);
        seq_printf(seq, "\tNumber of Additional TX channel: %d\n",
                   priv->dma_cap.number_tx_channel);
        seq_printf(seq, "\tEnhanced descriptors: %s\n",
                   (priv->dma_cap.enh_desc) ? "Y" : "N");

        return 0;
}
DEFINE_SHOW_ATTRIBUTE(stmmac_dma_cap);

static int stmmac_init_fs(struct net_device *dev)
{
        struct stmmac_priv *priv = netdev_priv(dev);

        /* Create per netdev entries */
        priv->dbgfs_dir = debugfs_create_dir(dev->name, stmmac_fs_dir);

        if (!priv->dbgfs_dir || IS_ERR(priv->dbgfs_dir)) {
                netdev_err(priv->dev, "ERROR failed to create debugfs directory\n");

                return -ENOMEM;
        }

        /* Entry to report DMA RX/TX rings */
        priv->dbgfs_rings_status =
                debugfs_create_file("descriptors_status", 0444,
                                    priv->dbgfs_dir, dev,
                                    &stmmac_rings_status_fops);

        if (!priv->dbgfs_rings_status || IS_ERR(priv->dbgfs_rings_status)) {
                netdev_err(priv->dev, "ERROR creating stmmac ring debugfs file\n");
                debugfs_remove_recursive(priv->dbgfs_dir);

                return -ENOMEM;
        }

        /* Entry to report the DMA HW features */
        priv->dbgfs_dma_cap = debugfs_create_file("dma_cap", 0444,
                                                  priv->dbgfs_dir,
                                                  dev, &stmmac_dma_cap_fops);

        if (!priv->dbgfs_dma_cap || IS_ERR(priv->dbgfs_dma_cap)) {
                netdev_err(priv->dev, "ERROR creating stmmac MMC debugfs file\n");
                debugfs_remove_recursive(priv->dbgfs_dir);

                return -ENOMEM;
        }

        return 0;
}

static void stmmac_exit_fs(struct net_device *dev)
{
        struct stmmac_priv *priv = netdev_priv(dev);

        debugfs_remove_recursive(priv->dbgfs_dir);
}
#endif /* CONFIG_DEBUG_FS */

static const struct net_device_ops stmmac_netdev_ops = {
        .ndo_open = stmmac_open,
        .ndo_start_xmit = stmmac_xmit,
        .ndo_stop = stmmac_release,
        .ndo_change_mtu = stmmac_change_mtu,
        .ndo_fix_features = stmmac_fix_features,
        .ndo_set_features = stmmac_set_features,
        .ndo_set_rx_mode = stmmac_set_rx_mode,
        .ndo_tx_timeout = stmmac_tx_timeout,
        .ndo_do_ioctl = stmmac_ioctl,
        .ndo_setup_tc = stmmac_setup_tc,
        .ndo_select_queue = stmmac_select_queue,
#ifdef CONFIG_NET_POLL_CONTROLLER
        .ndo_poll_controller = stmmac_poll_controller,
#endif
        .ndo_set_mac_address = stmmac_set_mac_address,
};

static void stmmac_reset_subtask(struct stmmac_priv *priv)
{
        if (!test_and_clear_bit(STMMAC_RESET_REQUESTED, &priv->state))
                return;
        if (test_bit(STMMAC_DOWN, &priv->state))
                return;

        netdev_err(priv->dev, "Reset adapter.\n");

        rtnl_lock();
        netif_trans_update(priv->dev);
        while (test_and_set_bit(STMMAC_RESETING, &priv->state))
                usleep_range(1000, 2000);

        set_bit(STMMAC_DOWN, &priv->state);
        dev_close(priv->dev);
        dev_open(priv->dev, NULL);
        clear_bit(STMMAC_DOWN, &priv->state);
        clear_bit(STMMAC_RESETING, &priv->state);
        rtnl_unlock();
}

static void stmmac_service_task(struct work_struct *work)
{
        struct stmmac_priv *priv = container_of(work, struct stmmac_priv,
                        service_task);

        stmmac_reset_subtask(priv);
        clear_bit(STMMAC_SERVICE_SCHED, &priv->state);
}

/**
 *  stmmac_hw_init - Init the MAC device
 *  @priv: driver private structure
 *  Description: this function is to configure the MAC device according to
 *  some platform parameters or the HW capability register. It prepares the
 *  driver to use either ring or chain modes and to setup either enhanced or
 *  normal descriptors.
 */
static int stmmac_hw_init(struct stmmac_priv *priv)
{
        int ret;

        /* dwmac-sun8i only work in chain mode */
        if (priv->plat->has_sun8i)
                chain_mode = 1;
        priv->chain_mode = chain_mode;

        /* Initialize HW Interface */
        ret = stmmac_hwif_init(priv);
        if (ret)
                return ret;

        /* Get the HW capability (new GMAC newer than 3.50a) */
        priv->hw_cap_support = stmmac_get_hw_features(priv);
        if (priv->hw_cap_support) {
                dev_info(priv->device, "DMA HW capability register supported\n");

                /* We can override some gmac/dma configuration fields: e.g.
                 * enh_desc, tx_coe (e.g. that are passed through the
                 * platform) with the values from the HW capability
                 * register (if supported).
                 */
                priv->plat->enh_desc = priv->dma_cap.enh_desc;
                priv->plat->pmt = priv->dma_cap.pmt_remote_wake_up;
                priv->hw->pmt = priv->plat->pmt;
                if (priv->dma_cap.hash_tb_sz) {
                        priv->hw->multicast_filter_bins =
                                        (BIT(priv->dma_cap.hash_tb_sz) << 5);
                        priv->hw->mcast_bits_log2 =
                                        ilog2(priv->hw->multicast_filter_bins);
                }

                /* TXCOE doesn't work in thresh DMA mode */
                if (priv->plat->force_thresh_dma_mode)
                        priv->plat->tx_coe = 0;
                else
                        priv->plat->tx_coe = priv->dma_cap.tx_coe;

                /* In case of GMAC4 rx_coe is from HW cap register. */
                priv->plat->rx_coe = priv->dma_cap.rx_coe;

                if (priv->dma_cap.rx_coe_type2)
                        priv->plat->rx_coe = STMMAC_RX_COE_TYPE2;
                else if (priv->dma_cap.rx_coe_type1)
                        priv->plat->rx_coe = STMMAC_RX_COE_TYPE1;

        } else {
                dev_info(priv->device, "No HW DMA feature register supported\n");
        }

        if (priv->plat->rx_coe) {
                priv->hw->rx_csum = priv->plat->rx_coe;
                dev_info(priv->device, "RX Checksum Offload Engine supported\n");
                if (priv->synopsys_id < DWMAC_CORE_4_00)
                        dev_info(priv->device, "COE Type %d\n", priv->hw->rx_csum);
        }
        if (priv->plat->tx_coe)
                dev_info(priv->device, "TX Checksum insertion supported\n");

        if (priv->plat->pmt) {
                dev_info(priv->device, "Wake-Up On Lan supported\n");
                device_set_wakeup_capable(priv->device, 1);
        }

        if (priv->dma_cap.tsoen)
                dev_info(priv->device, "TSO supported\n");

        /* Run HW quirks, if any */
        if (priv->hwif_quirks) {
                ret = priv->hwif_quirks(priv);
                if (ret)
                        return ret;
        }

        /* Rx Watchdog is available in the COREs newer than the 3.40.
         * In some case, for example on bugged HW this feature
         * has to be disable and this can be done by passing the
         * riwt_off field from the platform.
         */
        if (((priv->synopsys_id >= DWMAC_CORE_3_50) ||
            (priv->plat->has_xgmac)) && (!priv->plat->riwt_off)) {
                priv->use_riwt = 1;
                dev_info(priv->device,
                         "Enable RX Mitigation via HW Watchdog Timer\n");
        }

        return 0;
}

/**
 * stmmac_dvr_probe
 * @device: device pointer
 * @plat_dat: platform data pointer
 * @res: stmmac resource pointer
 * Description: this is the main probe function used to
 * call the alloc_etherdev, allocate the priv structure.
 * Return:
 * returns 0 on success, otherwise errno.
 */
int stmmac_dvr_probe(struct device *device,
                     struct plat_stmmacenet_data *plat_dat,
                     struct stmmac_resources *res)
{
        struct net_device *ndev = NULL;
        struct stmmac_priv *priv;
        u32 queue, rxq, maxq;
        int i, ret = 0;

        ndev = devm_alloc_etherdev_mqs(device, sizeof(struct stmmac_priv),
                                       MTL_MAX_TX_QUEUES, MTL_MAX_RX_QUEUES);
        if (!ndev)
                return -ENOMEM;

        SET_NETDEV_DEV(ndev, device);

        priv = netdev_priv(ndev);
        priv->device = device;
        priv->dev = ndev;

        stmmac_set_ethtool_ops(ndev);
        priv->pause = pause;
        priv->plat = plat_dat;
        priv->ioaddr = res->addr;
        priv->dev->base_addr = (unsigned long)res->addr;

        priv->dev->irq = res->irq;
        priv->wol_irq = res->wol_irq;
        priv->lpi_irq = res->lpi_irq;

        if (!IS_ERR_OR_NULL(res->mac))
                memcpy(priv->dev->dev_addr, res->mac, ETH_ALEN);

        dev_set_drvdata(device, priv->dev);

        /* Verify driver arguments */
        stmmac_verify_args();

        /* Allocate workqueue */
        priv->wq = create_singlethread_workqueue("stmmac_wq");
        if (!priv->wq) {
                dev_err(priv->device, "failed to create workqueue\n");
                return -ENOMEM;
        }

        INIT_WORK(&priv->service_task, stmmac_service_task);

        /* Override with kernel parameters if supplied XXX CRS XXX
         * this needs to have multiple instances
         */
        if ((phyaddr >= 0) && (phyaddr <= 31))
                priv->plat->phy_addr = phyaddr;

        if (priv->plat->stmmac_rst) {
                ret = reset_control_assert(priv->plat->stmmac_rst);
                reset_control_deassert(priv->plat->stmmac_rst);
                /* Some reset controllers have only reset callback instead of
                 * assert + deassert callbacks pair.
                 */
                if (ret == -ENOTSUPP)
                        reset_control_reset(priv->plat->stmmac_rst);
        }

        /* Init MAC and get the capabilities */
        ret = stmmac_hw_init(priv);
        if (ret)
                goto error_hw_init;

        stmmac_check_ether_addr(priv);

        /* Configure real RX and TX queues */
        netif_set_real_num_rx_queues(ndev, priv->plat->rx_queues_to_use);
        netif_set_real_num_tx_queues(ndev, priv->plat->tx_queues_to_use);

        ndev->netdev_ops = &stmmac_netdev_ops;

        ndev->hw_features = NETIF_F_SG | NETIF_F_IP_CSUM | NETIF_F_IPV6_CSUM |
                            NETIF_F_RXCSUM;

        ret = stmmac_tc_init(priv, priv);
        if (!ret) {
                ndev->hw_features |= NETIF_F_HW_TC;
        }

        if ((priv->plat->tso_en) && (priv->dma_cap.tsoen)) {
                ndev->hw_features |= NETIF_F_TSO | NETIF_F_TSO6;
                priv->tso = true;
                dev_info(priv->device, "TSO feature enabled\n");
        }

        if (priv->dma_cap.addr64) {
                ret = dma_set_mask_and_coherent(device,
                                DMA_BIT_MASK(priv->dma_cap.addr64));
                if (!ret) {
                        dev_info(priv->device, "Using %d bits DMA width\n",
                                 priv->dma_cap.addr64);
                } else {
                        ret = dma_set_mask_and_coherent(device, DMA_BIT_MASK(32));
                        if (ret) {
                                dev_err(priv->device, "Failed to set DMA Mask\n");
                                goto error_hw_init;
                        }

                        priv->dma_cap.addr64 = 32;
                }
        }

        ndev->features |= ndev->hw_features | NETIF_F_HIGHDMA;
        ndev->watchdog_timeo = msecs_to_jiffies(watchdog);
#ifdef STMMAC_VLAN_TAG_USED
        /* Both mac100 and gmac support receive VLAN tag detection */
        ndev->features |= NETIF_F_HW_VLAN_CTAG_RX | NETIF_F_HW_VLAN_STAG_RX;
#endif
        priv->msg_enable = netif_msg_init(debug, default_msg_level);

        /* Initialize RSS */
        rxq = priv->plat->rx_queues_to_use;
        netdev_rss_key_fill(priv->rss.key, sizeof(priv->rss.key));
        for (i = 0; i < ARRAY_SIZE(priv->rss.table); i++)
                priv->rss.table[i] = ethtool_rxfh_indir_default(i, rxq);

        if (priv->dma_cap.rssen && priv->plat->rss_en)
                ndev->features |= NETIF_F_RXHASH;

        /* MTU range: 46 - hw-specific max */
        ndev->min_mtu = ETH_ZLEN - ETH_HLEN;
        if ((priv->plat->enh_desc) || (priv->synopsys_id >= DWMAC_CORE_4_00))
                ndev->max_mtu = JUMBO_LEN;
        else if (priv->plat->has_xgmac)
                ndev->max_mtu = XGMAC_JUMBO_LEN;
        else
                ndev->max_mtu = SKB_MAX_HEAD(NET_SKB_PAD + NET_IP_ALIGN);
        /* Will not overwrite ndev->max_mtu if plat->maxmtu > ndev->max_mtu
         * as well as plat->maxmtu < ndev->min_mtu which is a invalid range.
         */
        if ((priv->plat->maxmtu < ndev->max_mtu) &&
            (priv->plat->maxmtu >= ndev->min_mtu))
                ndev->max_mtu = priv->plat->maxmtu;
        else if (priv->plat->maxmtu < ndev->min_mtu)
                dev_warn(priv->device,
                         "%s: warning: maxmtu having invalid value (%d)\n",
                         __func__, priv->plat->maxmtu);

        if (flow_ctrl)
                priv->flow_ctrl = FLOW_AUTO;    /* RX/TX pause on */

        /* Setup channels NAPI */
        maxq = max(priv->plat->rx_queues_to_use, priv->plat->tx_queues_to_use);

        for (queue = 0; queue < maxq; queue++) {
                struct stmmac_channel *ch = &priv->channel[queue];

                ch->priv_data = priv;
                ch->index = queue;

                if (queue < priv->plat->rx_queues_to_use) {
                        netif_napi_add(ndev, &ch->rx_napi, stmmac_napi_poll_rx,
                                       NAPI_POLL_WEIGHT);
                }
                if (queue < priv->plat->tx_queues_to_use) {
                        netif_tx_napi_add(ndev, &ch->tx_napi,
                                          stmmac_napi_poll_tx,
                                          NAPI_POLL_WEIGHT);
                }
        }

        mutex_init(&priv->lock);

        /* If a specific clk_csr value is passed from the platform
         * this means that the CSR Clock Range selection cannot be
         * changed at run-time and it is fixed. Viceversa the driver'll try to
         * set the MDC clock dynamically according to the csr actual
         * clock input.
         */
        if (priv->plat->clk_csr >= 0)
                priv->clk_csr = priv->plat->clk_csr;
        else
                stmmac_clk_csr_set(priv);

        stmmac_check_pcs_mode(priv);

        if (priv->hw->pcs != STMMAC_PCS_RGMII  &&
            priv->hw->pcs != STMMAC_PCS_TBI &&
            priv->hw->pcs != STMMAC_PCS_RTBI) {
                /* MDIO bus Registration */
                ret = stmmac_mdio_register(ndev);
                if (ret < 0) {
                        dev_err(priv->device,
                                "%s: MDIO bus (id: %d) registration failed",
                                __func__, priv->plat->bus_id);
                        goto error_mdio_register;
                }
        }

        ret = stmmac_phy_setup(priv);
        if (ret) {
                netdev_err(ndev, "failed to setup phy (%d)\n", ret);
                goto error_phy_setup;
        }

        ret = register_netdev(ndev);
        if (ret) {
                dev_err(priv->device, "%s: ERROR %i registering the device\n",
                        __func__, ret);
                goto error_netdev_register;
        }

#ifdef CONFIG_DEBUG_FS
        ret = stmmac_init_fs(ndev);
        if (ret < 0)
                netdev_warn(priv->dev, "%s: failed debugFS registration\n",
                            __func__);
#endif

        return ret;

error_netdev_register:
        phylink_destroy(priv->phylink);
error_phy_setup:
        if (priv->hw->pcs != STMMAC_PCS_RGMII &&
            priv->hw->pcs != STMMAC_PCS_TBI &&
            priv->hw->pcs != STMMAC_PCS_RTBI)
                stmmac_mdio_unregister(ndev);
error_mdio_register:
        for (queue = 0; queue < maxq; queue++) {
                struct stmmac_channel *ch = &priv->channel[queue];

                if (queue < priv->plat->rx_queues_to_use)
                        netif_napi_del(&ch->rx_napi);
                if (queue < priv->plat->tx_queues_to_use)
                        netif_napi_del(&ch->tx_napi);
        }
error_hw_init:
        destroy_workqueue(priv->wq);

        return ret;
}
EXPORT_SYMBOL_GPL(stmmac_dvr_probe);

/**
 * stmmac_dvr_remove
 * @dev: device pointer
 * Description: this function resets the TX/RX processes, disables the MAC RX/TX
 * changes the link status, releases the DMA descriptor rings.
 */
int stmmac_dvr_remove(struct device *dev)
{
        struct net_device *ndev = dev_get_drvdata(dev);
        struct stmmac_priv *priv = netdev_priv(ndev);

        netdev_info(priv->dev, "%s: removing driver", __func__);

#ifdef CONFIG_DEBUG_FS
        stmmac_exit_fs(ndev);
#endif
        stmmac_stop_all_dma(priv);

        stmmac_mac_set(priv, priv->ioaddr, false);
        netif_carrier_off(ndev);
        unregister_netdev(ndev);
        phylink_destroy(priv->phylink);
        if (priv->plat->stmmac_rst)
                reset_control_assert(priv->plat->stmmac_rst);
        clk_disable_unprepare(priv->plat->pclk);
        clk_disable_unprepare(priv->plat->stmmac_clk);
        if (priv->hw->pcs != STMMAC_PCS_RGMII &&
            priv->hw->pcs != STMMAC_PCS_TBI &&
            priv->hw->pcs != STMMAC_PCS_RTBI)
                stmmac_mdio_unregister(ndev);
        destroy_workqueue(priv->wq);
        mutex_destroy(&priv->lock);

        return 0;
}
EXPORT_SYMBOL_GPL(stmmac_dvr_remove);

/**
 * stmmac_suspend - suspend callback
 * @dev: device pointer
 * Description: this is the function to suspend the device and it is called
 * by the platform driver to stop the network queue, release the resources,
 * program the PMT register (for WoL), clean and release driver resources.
 */
int stmmac_suspend(struct device *dev)
{
        struct net_device *ndev = dev_get_drvdata(dev);
        struct stmmac_priv *priv = netdev_priv(ndev);

        if (!ndev || !netif_running(ndev))
                return 0;

        phylink_stop(priv->phylink);

        mutex_lock(&priv->lock);

        netif_device_detach(ndev);
        stmmac_stop_all_queues(priv);

        stmmac_disable_all_queues(priv);

        /* Stop TX/RX DMA */
        stmmac_stop_all_dma(priv);

        /* Enable Power down mode by programming the PMT regs */
        if (device_may_wakeup(priv->device)) {
                stmmac_pmt(priv, priv->hw, priv->wolopts);
                priv->irq_wake = 1;
        } else {
                stmmac_mac_set(priv, priv->ioaddr, false);
                pinctrl_pm_select_sleep_state(priv->device);
                /* Disable clock in case of PWM is off */
                clk_disable(priv->plat->pclk);
                clk_disable(priv->plat->stmmac_clk);
        }
        mutex_unlock(&priv->lock);

        priv->speed = SPEED_UNKNOWN;
        return 0;
}
EXPORT_SYMBOL_GPL(stmmac_suspend);

/**
 * stmmac_reset_queues_param - reset queue parameters
 * @dev: device pointer
 */
static void stmmac_reset_queues_param(struct stmmac_priv *priv)
{
        u32 rx_cnt = priv->plat->rx_queues_to_use;
        u32 tx_cnt = priv->plat->tx_queues_to_use;
        u32 queue;

        for (queue = 0; queue < rx_cnt; queue++) {
                struct stmmac_rx_queue *rx_q = &priv->rx_queue[queue];

                rx_q->cur_rx = 0;
                rx_q->dirty_rx = 0;
        }

        for (queue = 0; queue < tx_cnt; queue++) {
                struct stmmac_tx_queue *tx_q = &priv->tx_queue[queue];

                tx_q->cur_tx = 0;
                tx_q->dirty_tx = 0;
                tx_q->mss = 0;
        }
}

/**
 * stmmac_resume - resume callback
 * @dev: device pointer
 * Description: when resume this function is invoked to setup the DMA and CORE
 * in a usable state.
 */
int stmmac_resume(struct device *dev)
{
        struct net_device *ndev = dev_get_drvdata(dev);
        struct stmmac_priv *priv = netdev_priv(ndev);

        if (!netif_running(ndev))
                return 0;

        /* Power Down bit, into the PM register, is cleared
         * automatically as soon as a magic packet or a Wake-up frame
         * is received. Anyway, it's better to manually clear
         * this bit because it can generate problems while resuming
         * from another devices (e.g. serial console).
         */
        if (device_may_wakeup(priv->device)) {
                mutex_lock(&priv->lock);
                stmmac_pmt(priv, priv->hw, 0);
                mutex_unlock(&priv->lock);
                priv->irq_wake = 0;
        } else {
                pinctrl_pm_select_default_state(priv->device);
                /* enable the clk previously disabled */
                clk_enable(priv->plat->stmmac_clk);
                clk_enable(priv->plat->pclk);
                /* reset the phy so that it's ready */
                if (priv->mii)
                        stmmac_mdio_reset(priv->mii);
        }

        netif_device_attach(ndev);

        mutex_lock(&priv->lock);

        stmmac_reset_queues_param(priv);

        stmmac_clear_descriptors(priv);

        stmmac_hw_setup(ndev, false);
        stmmac_init_coalesce(priv);
        stmmac_set_rx_mode(ndev);

        stmmac_enable_all_queues(priv);

        stmmac_start_all_queues(priv);

        mutex_unlock(&priv->lock);

        phylink_start(priv->phylink);

        return 0;
}
EXPORT_SYMBOL_GPL(stmmac_resume);

#ifndef MODULE
static int __init stmmac_cmdline_opt(char *str)
{
        char *opt;

        if (!str || !*str)
                return -EINVAL;
        while ((opt = strsep(&str, ",")) != NULL) {
                if (!strncmp(opt, "debug:", 6)) {
                        if (kstrtoint(opt + 6, 0, &debug))
                                goto err;
                } else if (!strncmp(opt, "phyaddr:", 8)) {
                        if (kstrtoint(opt + 8, 0, &phyaddr))
                                goto err;
                } else if (!strncmp(opt, "buf_sz:", 7)) {
                        if (kstrtoint(opt + 7, 0, &buf_sz))
                                goto err;
                } else if (!strncmp(opt, "tc:", 3)) {
                        if (kstrtoint(opt + 3, 0, &tc))
                                goto err;
                } else if (!strncmp(opt, "watchdog:", 9)) {
                        if (kstrtoint(opt + 9, 0, &watchdog))
                                goto err;
                } else if (!strncmp(opt, "flow_ctrl:", 10)) {
                        if (kstrtoint(opt + 10, 0, &flow_ctrl))
                                goto err;
                } else if (!strncmp(opt, "pause:", 6)) {
                        if (kstrtoint(opt + 6, 0, &pause))
                                goto err;
                } else if (!strncmp(opt, "eee_timer:", 10)) {
                        if (kstrtoint(opt + 10, 0, &eee_timer))
                                goto err;
                } else if (!strncmp(opt, "chain_mode:", 11)) {
                        if (kstrtoint(opt + 11, 0, &chain_mode))
                                goto err;
                }
        }
        return 0;

err:
        pr_err("%s: ERROR broken module parameter conversion", __func__);
        return -EINVAL;
}

__setup("stmmaceth=", stmmac_cmdline_opt);
#endif /* MODULE */

static int __init stmmac_init(void)
{
#ifdef CONFIG_DEBUG_FS
        /* Create debugfs main directory if it doesn't exist yet */
        if (!stmmac_fs_dir) {
                stmmac_fs_dir = debugfs_create_dir(STMMAC_RESOURCE_NAME, NULL);

                if (!stmmac_fs_dir || IS_ERR(stmmac_fs_dir)) {
                        pr_err("ERROR %s, debugfs create directory failed\n",
                               STMMAC_RESOURCE_NAME);

                        return -ENOMEM;
                }
        }
#endif

        return 0;
}

static void __exit stmmac_exit(void)
{
#ifdef CONFIG_DEBUG_FS
        debugfs_remove_recursive(stmmac_fs_dir);
#endif
}

module_init(stmmac_init)
module_exit(stmmac_exit)

MODULE_DESCRIPTION("STMMAC 10/100/1000 Ethernet device driver");
MODULE_AUTHOR("Giuseppe Cavallaro <peppe.cavallaro@st.com>");
MODULE_LICENSE("GPL");