net/ngbe: support jumbo frame

[dpdk.git] / drivers / net / ngbe / ngbe_rxtx.c

/* SPDX-License-Identifier: BSD-3-Clause
 * Copyright(c) 2018-2021 Beijing WangXun Technology Co., Ltd.
 * Copyright(c) 2010-2017 Intel Corporation
 */

#include <sys/queue.h>

#include <stdint.h>
#include <rte_ethdev.h>
#include <ethdev_driver.h>
#include <rte_malloc.h>
#include <rte_net.h>

#include "ngbe_logs.h"
#include "base/ngbe.h"
#include "ngbe_ethdev.h"
#include "ngbe_rxtx.h"

/* Bit Mask to indicate what bits required for building Tx context */
static const u64 NGBE_TX_OFFLOAD_MASK = (RTE_MBUF_F_TX_IP_CKSUM |
                RTE_MBUF_F_TX_OUTER_IPV6 |
                RTE_MBUF_F_TX_OUTER_IPV4 |
                RTE_MBUF_F_TX_IPV6 |
                RTE_MBUF_F_TX_IPV4 |
                RTE_MBUF_F_TX_L4_MASK |
                RTE_MBUF_F_TX_TCP_SEG |
                RTE_MBUF_F_TX_TUNNEL_MASK |
                RTE_MBUF_F_TX_OUTER_IP_CKSUM);
#define NGBE_TX_OFFLOAD_NOTSUP_MASK \
                (RTE_MBUF_F_TX_OFFLOAD_MASK ^ NGBE_TX_OFFLOAD_MASK)

/*
 * Prefetch a cache line into all cache levels.
 */
#define rte_ngbe_prefetch(p)   rte_prefetch0(p)

/*********************************************************************
 *
 *  Tx functions
 *
 **********************************************************************/

/*
 * Check for descriptors with their DD bit set and free mbufs.
 * Return the total number of buffers freed.
 */
static __rte_always_inline int
ngbe_tx_free_bufs(struct ngbe_tx_queue *txq)
{
        struct ngbe_tx_entry *txep;
        uint32_t status;
        int i, nb_free = 0;
        struct rte_mbuf *m, *free[RTE_NGBE_TX_MAX_FREE_BUF_SZ];

        /* check DD bit on threshold descriptor */
        status = txq->tx_ring[txq->tx_next_dd].dw3;
        if (!(status & rte_cpu_to_le_32(NGBE_TXD_DD))) {
                if (txq->nb_tx_free >> 1 < txq->tx_free_thresh)
                        ngbe_set32_masked(txq->tdc_reg_addr,
                                NGBE_TXCFG_FLUSH, NGBE_TXCFG_FLUSH);
                return 0;
        }

        /*
         * first buffer to free from S/W ring is at index
         * tx_next_dd - (tx_free_thresh-1)
         */
        txep = &txq->sw_ring[txq->tx_next_dd - (txq->tx_free_thresh - 1)];
        for (i = 0; i < txq->tx_free_thresh; ++i, ++txep) {
                /* free buffers one at a time */
                m = rte_pktmbuf_prefree_seg(txep->mbuf);
                txep->mbuf = NULL;

                if (unlikely(m == NULL))
                        continue;

                if (nb_free >= RTE_NGBE_TX_MAX_FREE_BUF_SZ ||
                    (nb_free > 0 && m->pool != free[0]->pool)) {
                        rte_mempool_put_bulk(free[0]->pool,
                                             (void **)free, nb_free);
                        nb_free = 0;
                }

                free[nb_free++] = m;
        }

        if (nb_free > 0)
                rte_mempool_put_bulk(free[0]->pool, (void **)free, nb_free);

        /* buffers were freed, update counters */
        txq->nb_tx_free = (uint16_t)(txq->nb_tx_free + txq->tx_free_thresh);
        txq->tx_next_dd = (uint16_t)(txq->tx_next_dd + txq->tx_free_thresh);
        if (txq->tx_next_dd >= txq->nb_tx_desc)
                txq->tx_next_dd = (uint16_t)(txq->tx_free_thresh - 1);

        return txq->tx_free_thresh;
}

/* Populate 4 descriptors with data from 4 mbufs */
static inline void
tx4(volatile struct ngbe_tx_desc *txdp, struct rte_mbuf **pkts)
{
        uint64_t buf_dma_addr;
        uint32_t pkt_len;
        int i;

        for (i = 0; i < 4; ++i, ++txdp, ++pkts) {
                buf_dma_addr = rte_mbuf_data_iova(*pkts);
                pkt_len = (*pkts)->data_len;

                /* write data to descriptor */
                txdp->qw0 = rte_cpu_to_le_64(buf_dma_addr);
                txdp->dw2 = cpu_to_le32(NGBE_TXD_FLAGS |
                                        NGBE_TXD_DATLEN(pkt_len));
                txdp->dw3 = cpu_to_le32(NGBE_TXD_PAYLEN(pkt_len));

                rte_prefetch0(&(*pkts)->pool);
        }
}

/* Populate 1 descriptor with data from 1 mbuf */
static inline void
tx1(volatile struct ngbe_tx_desc *txdp, struct rte_mbuf **pkts)
{
        uint64_t buf_dma_addr;
        uint32_t pkt_len;

        buf_dma_addr = rte_mbuf_data_iova(*pkts);
        pkt_len = (*pkts)->data_len;

        /* write data to descriptor */
        txdp->qw0 = cpu_to_le64(buf_dma_addr);
        txdp->dw2 = cpu_to_le32(NGBE_TXD_FLAGS |
                                NGBE_TXD_DATLEN(pkt_len));
        txdp->dw3 = cpu_to_le32(NGBE_TXD_PAYLEN(pkt_len));

        rte_prefetch0(&(*pkts)->pool);
}

/*
 * Fill H/W descriptor ring with mbuf data.
 * Copy mbuf pointers to the S/W ring.
 */
static inline void
ngbe_tx_fill_hw_ring(struct ngbe_tx_queue *txq, struct rte_mbuf **pkts,
                      uint16_t nb_pkts)
{
        volatile struct ngbe_tx_desc *txdp = &txq->tx_ring[txq->tx_tail];
        struct ngbe_tx_entry *txep = &txq->sw_ring[txq->tx_tail];
        const int N_PER_LOOP = 4;
        const int N_PER_LOOP_MASK = N_PER_LOOP - 1;
        int mainpart, leftover;
        int i, j;

        /*
         * Process most of the packets in chunks of N pkts.  Any
         * leftover packets will get processed one at a time.
         */
        mainpart = (nb_pkts & ((uint32_t)~N_PER_LOOP_MASK));
        leftover = (nb_pkts & ((uint32_t)N_PER_LOOP_MASK));
        for (i = 0; i < mainpart; i += N_PER_LOOP) {
                /* Copy N mbuf pointers to the S/W ring */
                for (j = 0; j < N_PER_LOOP; ++j)
                        (txep + i + j)->mbuf = *(pkts + i + j);
                tx4(txdp + i, pkts + i);
        }

        if (unlikely(leftover > 0)) {
                for (i = 0; i < leftover; ++i) {
                        (txep + mainpart + i)->mbuf = *(pkts + mainpart + i);
                        tx1(txdp + mainpart + i, pkts + mainpart + i);
                }
        }
}

static inline uint16_t
tx_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
             uint16_t nb_pkts)
{
        struct ngbe_tx_queue *txq = (struct ngbe_tx_queue *)tx_queue;
        uint16_t n = 0;

        /*
         * Begin scanning the H/W ring for done descriptors when the
         * number of available descriptors drops below tx_free_thresh.
         * For each done descriptor, free the associated buffer.
         */
        if (txq->nb_tx_free < txq->tx_free_thresh)
                ngbe_tx_free_bufs(txq);

        /* Only use descriptors that are available */
        nb_pkts = (uint16_t)RTE_MIN(txq->nb_tx_free, nb_pkts);
        if (unlikely(nb_pkts == 0))
                return 0;

        /* Use exactly nb_pkts descriptors */
        txq->nb_tx_free = (uint16_t)(txq->nb_tx_free - nb_pkts);

        /*
         * At this point, we know there are enough descriptors in the
         * ring to transmit all the packets.  This assumes that each
         * mbuf contains a single segment, and that no new offloads
         * are expected, which would require a new context descriptor.
         */

        /*
         * See if we're going to wrap-around. If so, handle the top
         * of the descriptor ring first, then do the bottom.  If not,
         * the processing looks just like the "bottom" part anyway...
         */
        if ((txq->tx_tail + nb_pkts) > txq->nb_tx_desc) {
                n = (uint16_t)(txq->nb_tx_desc - txq->tx_tail);
                ngbe_tx_fill_hw_ring(txq, tx_pkts, n);
                txq->tx_tail = 0;
        }

        /* Fill H/W descriptor ring with mbuf data */
        ngbe_tx_fill_hw_ring(txq, tx_pkts + n, (uint16_t)(nb_pkts - n));
        txq->tx_tail = (uint16_t)(txq->tx_tail + (nb_pkts - n));

        /*
         * Check for wrap-around. This would only happen if we used
         * up to the last descriptor in the ring, no more, no less.
         */
        if (txq->tx_tail >= txq->nb_tx_desc)
                txq->tx_tail = 0;

        PMD_TX_LOG(DEBUG, "port_id=%u queue_id=%u tx_tail=%u nb_tx=%u",
                   (uint16_t)txq->port_id, (uint16_t)txq->queue_id,
                   (uint16_t)txq->tx_tail, (uint16_t)nb_pkts);

        /* update tail pointer */
        rte_wmb();
        ngbe_set32_relaxed(txq->tdt_reg_addr, txq->tx_tail);

        return nb_pkts;
}

uint16_t
ngbe_xmit_pkts_simple(void *tx_queue, struct rte_mbuf **tx_pkts,
                       uint16_t nb_pkts)
{
        uint16_t nb_tx;

        /* Try to transmit at least chunks of TX_MAX_BURST pkts */
        if (likely(nb_pkts <= RTE_PMD_NGBE_TX_MAX_BURST))
                return tx_xmit_pkts(tx_queue, tx_pkts, nb_pkts);

        /* transmit more than the max burst, in chunks of TX_MAX_BURST */
        nb_tx = 0;
        while (nb_pkts != 0) {
                uint16_t ret, n;

                n = (uint16_t)RTE_MIN(nb_pkts, RTE_PMD_NGBE_TX_MAX_BURST);
                ret = tx_xmit_pkts(tx_queue, &tx_pkts[nb_tx], n);
                nb_tx = (uint16_t)(nb_tx + ret);
                nb_pkts = (uint16_t)(nb_pkts - ret);
                if (ret < n)
                        break;
        }

        return nb_tx;
}

static inline void
ngbe_set_xmit_ctx(struct ngbe_tx_queue *txq,
                volatile struct ngbe_tx_ctx_desc *ctx_txd,
                uint64_t ol_flags, union ngbe_tx_offload tx_offload)
{
        union ngbe_tx_offload tx_offload_mask;
        uint32_t type_tucmd_mlhl;
        uint32_t mss_l4len_idx;
        uint32_t ctx_idx;
        uint32_t vlan_macip_lens;
        uint32_t tunnel_seed;

        ctx_idx = txq->ctx_curr;
        tx_offload_mask.data[0] = 0;
        tx_offload_mask.data[1] = 0;

        /* Specify which HW CTX to upload. */
        mss_l4len_idx = NGBE_TXD_IDX(ctx_idx);
        type_tucmd_mlhl = NGBE_TXD_CTXT;

        tx_offload_mask.ptid |= ~0;
        type_tucmd_mlhl |= NGBE_TXD_PTID(tx_offload.ptid);

        /* check if TCP segmentation required for this packet */
        if (ol_flags & RTE_MBUF_F_TX_TCP_SEG) {
                tx_offload_mask.l2_len |= ~0;
                tx_offload_mask.l3_len |= ~0;
                tx_offload_mask.l4_len |= ~0;
                tx_offload_mask.tso_segsz |= ~0;
                mss_l4len_idx |= NGBE_TXD_MSS(tx_offload.tso_segsz);
                mss_l4len_idx |= NGBE_TXD_L4LEN(tx_offload.l4_len);
        } else { /* no TSO, check if hardware checksum is needed */
                if (ol_flags & RTE_MBUF_F_TX_IP_CKSUM) {
                        tx_offload_mask.l2_len |= ~0;
                        tx_offload_mask.l3_len |= ~0;
                }

                switch (ol_flags & RTE_MBUF_F_TX_L4_MASK) {
                case RTE_MBUF_F_TX_UDP_CKSUM:
                        mss_l4len_idx |=
                                NGBE_TXD_L4LEN(sizeof(struct rte_udp_hdr));
                        tx_offload_mask.l2_len |= ~0;
                        tx_offload_mask.l3_len |= ~0;
                        break;
                case RTE_MBUF_F_TX_TCP_CKSUM:
                        mss_l4len_idx |=
                                NGBE_TXD_L4LEN(sizeof(struct rte_tcp_hdr));
                        tx_offload_mask.l2_len |= ~0;
                        tx_offload_mask.l3_len |= ~0;
                        break;
                case RTE_MBUF_F_TX_SCTP_CKSUM:
                        mss_l4len_idx |=
                                NGBE_TXD_L4LEN(sizeof(struct rte_sctp_hdr));
                        tx_offload_mask.l2_len |= ~0;
                        tx_offload_mask.l3_len |= ~0;
                        break;
                default:
                        break;
                }
        }

        vlan_macip_lens = NGBE_TXD_IPLEN(tx_offload.l3_len >> 1);

        if (ol_flags & RTE_MBUF_F_TX_TUNNEL_MASK) {
                tx_offload_mask.outer_tun_len |= ~0;
                tx_offload_mask.outer_l2_len |= ~0;
                tx_offload_mask.outer_l3_len |= ~0;
                tx_offload_mask.l2_len |= ~0;
                tunnel_seed = NGBE_TXD_ETUNLEN(tx_offload.outer_tun_len >> 1);
                tunnel_seed |= NGBE_TXD_EIPLEN(tx_offload.outer_l3_len >> 2);

                switch (ol_flags & RTE_MBUF_F_TX_TUNNEL_MASK) {
                case RTE_MBUF_F_TX_TUNNEL_IPIP:
                        /* for non UDP / GRE tunneling, set to 0b */
                        break;
                default:
                        PMD_TX_LOG(ERR, "Tunnel type not supported");
                        return;
                }
                vlan_macip_lens |= NGBE_TXD_MACLEN(tx_offload.outer_l2_len);
        } else {
                tunnel_seed = 0;
                vlan_macip_lens |= NGBE_TXD_MACLEN(tx_offload.l2_len);
        }

        txq->ctx_cache[ctx_idx].flags = ol_flags;
        txq->ctx_cache[ctx_idx].tx_offload.data[0] =
                tx_offload_mask.data[0] & tx_offload.data[0];
        txq->ctx_cache[ctx_idx].tx_offload.data[1] =
                tx_offload_mask.data[1] & tx_offload.data[1];
        txq->ctx_cache[ctx_idx].tx_offload_mask = tx_offload_mask;

        ctx_txd->dw0 = rte_cpu_to_le_32(vlan_macip_lens);
        ctx_txd->dw1 = rte_cpu_to_le_32(tunnel_seed);
        ctx_txd->dw2 = rte_cpu_to_le_32(type_tucmd_mlhl);
        ctx_txd->dw3 = rte_cpu_to_le_32(mss_l4len_idx);
}

/*
 * Check which hardware context can be used. Use the existing match
 * or create a new context descriptor.
 */
static inline uint32_t
what_ctx_update(struct ngbe_tx_queue *txq, uint64_t flags,
                   union ngbe_tx_offload tx_offload)
{
        /* If match with the current used context */
        if (likely(txq->ctx_cache[txq->ctx_curr].flags == flags &&
                   (txq->ctx_cache[txq->ctx_curr].tx_offload.data[0] ==
                    (txq->ctx_cache[txq->ctx_curr].tx_offload_mask.data[0]
                     & tx_offload.data[0])) &&
                   (txq->ctx_cache[txq->ctx_curr].tx_offload.data[1] ==
                    (txq->ctx_cache[txq->ctx_curr].tx_offload_mask.data[1]
                     & tx_offload.data[1]))))
                return txq->ctx_curr;

        /* What if match with the next context  */
        txq->ctx_curr ^= 1;
        if (likely(txq->ctx_cache[txq->ctx_curr].flags == flags &&
                   (txq->ctx_cache[txq->ctx_curr].tx_offload.data[0] ==
                    (txq->ctx_cache[txq->ctx_curr].tx_offload_mask.data[0]
                     & tx_offload.data[0])) &&
                   (txq->ctx_cache[txq->ctx_curr].tx_offload.data[1] ==
                    (txq->ctx_cache[txq->ctx_curr].tx_offload_mask.data[1]
                     & tx_offload.data[1]))))
                return txq->ctx_curr;

        /* Mismatch, use the previous context */
        return NGBE_CTX_NUM;
}

static inline uint32_t
tx_desc_cksum_flags_to_olinfo(uint64_t ol_flags)
{
        uint32_t tmp = 0;

        if ((ol_flags & RTE_MBUF_F_TX_L4_MASK) != RTE_MBUF_F_TX_L4_NO_CKSUM) {
                tmp |= NGBE_TXD_CC;
                tmp |= NGBE_TXD_L4CS;
        }
        if (ol_flags & RTE_MBUF_F_TX_IP_CKSUM) {
                tmp |= NGBE_TXD_CC;
                tmp |= NGBE_TXD_IPCS;
        }
        if (ol_flags & RTE_MBUF_F_TX_OUTER_IP_CKSUM) {
                tmp |= NGBE_TXD_CC;
                tmp |= NGBE_TXD_EIPCS;
        }
        if (ol_flags & RTE_MBUF_F_TX_TCP_SEG) {
                tmp |= NGBE_TXD_CC;
                /* implies IPv4 cksum */
                if (ol_flags & RTE_MBUF_F_TX_IPV4)
                        tmp |= NGBE_TXD_IPCS;
                tmp |= NGBE_TXD_L4CS;
        }

        return tmp;
}

static inline uint32_t
tx_desc_ol_flags_to_cmdtype(uint64_t ol_flags)
{
        uint32_t cmdtype = 0;

        if (ol_flags & RTE_MBUF_F_TX_TCP_SEG)
                cmdtype |= NGBE_TXD_TSE;
        return cmdtype;
}

static inline uint8_t
tx_desc_ol_flags_to_ptid(uint64_t oflags, uint32_t ptype)
{
        bool tun;

        if (ptype)
                return ngbe_encode_ptype(ptype);

        /* Only support flags in NGBE_TX_OFFLOAD_MASK */
        tun = !!(oflags & RTE_MBUF_F_TX_TUNNEL_MASK);

        /* L2 level */
        ptype = RTE_PTYPE_L2_ETHER;

        /* L3 level */
        if (oflags & (RTE_MBUF_F_TX_OUTER_IPV4 | RTE_MBUF_F_TX_OUTER_IP_CKSUM))
                ptype |= RTE_PTYPE_L3_IPV4;
        else if (oflags & (RTE_MBUF_F_TX_OUTER_IPV6))
                ptype |= RTE_PTYPE_L3_IPV6;

        if (oflags & (RTE_MBUF_F_TX_IPV4 | RTE_MBUF_F_TX_IP_CKSUM))
                ptype |= (tun ? RTE_PTYPE_INNER_L3_IPV4 : RTE_PTYPE_L3_IPV4);
        else if (oflags & (RTE_MBUF_F_TX_IPV6))
                ptype |= (tun ? RTE_PTYPE_INNER_L3_IPV6 : RTE_PTYPE_L3_IPV6);

        /* L4 level */
        switch (oflags & (RTE_MBUF_F_TX_L4_MASK)) {
        case RTE_MBUF_F_TX_TCP_CKSUM:
                ptype |= (tun ? RTE_PTYPE_INNER_L4_TCP : RTE_PTYPE_L4_TCP);
                break;
        case RTE_MBUF_F_TX_UDP_CKSUM:
                ptype |= (tun ? RTE_PTYPE_INNER_L4_UDP : RTE_PTYPE_L4_UDP);
                break;
        case RTE_MBUF_F_TX_SCTP_CKSUM:
                ptype |= (tun ? RTE_PTYPE_INNER_L4_SCTP : RTE_PTYPE_L4_SCTP);
                break;
        }

        if (oflags & RTE_MBUF_F_TX_TCP_SEG)
                ptype |= (tun ? RTE_PTYPE_INNER_L4_TCP : RTE_PTYPE_L4_TCP);

        /* Tunnel */
        switch (oflags & RTE_MBUF_F_TX_TUNNEL_MASK) {
        case RTE_MBUF_F_TX_TUNNEL_IPIP:
        case RTE_MBUF_F_TX_TUNNEL_IP:
                ptype |= RTE_PTYPE_L2_ETHER |
                         RTE_PTYPE_L3_IPV4 |
                         RTE_PTYPE_TUNNEL_IP;
                break;
        }

        return ngbe_encode_ptype(ptype);
}

/* Reset transmit descriptors after they have been used */
static inline int
ngbe_xmit_cleanup(struct ngbe_tx_queue *txq)
{
        struct ngbe_tx_entry *sw_ring = txq->sw_ring;
        volatile struct ngbe_tx_desc *txr = txq->tx_ring;
        uint16_t last_desc_cleaned = txq->last_desc_cleaned;
        uint16_t nb_tx_desc = txq->nb_tx_desc;
        uint16_t desc_to_clean_to;
        uint16_t nb_tx_to_clean;
        uint32_t status;

        /* Determine the last descriptor needing to be cleaned */
        desc_to_clean_to = (uint16_t)(last_desc_cleaned + txq->tx_free_thresh);
        if (desc_to_clean_to >= nb_tx_desc)
                desc_to_clean_to = (uint16_t)(desc_to_clean_to - nb_tx_desc);

        /* Check to make sure the last descriptor to clean is done */
        desc_to_clean_to = sw_ring[desc_to_clean_to].last_id;
        status = txr[desc_to_clean_to].dw3;
        if (!(status & rte_cpu_to_le_32(NGBE_TXD_DD))) {
                PMD_TX_LOG(DEBUG,
                        "Tx descriptor %4u is not done"
                        "(port=%d queue=%d)",
                        desc_to_clean_to,
                        txq->port_id, txq->queue_id);
                if (txq->nb_tx_free >> 1 < txq->tx_free_thresh)
                        ngbe_set32_masked(txq->tdc_reg_addr,
                                NGBE_TXCFG_FLUSH, NGBE_TXCFG_FLUSH);
                /* Failed to clean any descriptors, better luck next time */
                return -(1);
        }

        /* Figure out how many descriptors will be cleaned */
        if (last_desc_cleaned > desc_to_clean_to)
                nb_tx_to_clean = (uint16_t)((nb_tx_desc - last_desc_cleaned) +
                                                        desc_to_clean_to);
        else
                nb_tx_to_clean = (uint16_t)(desc_to_clean_to -
                                                last_desc_cleaned);

        PMD_TX_LOG(DEBUG,
                "Cleaning %4u Tx descriptors: %4u to %4u (port=%d queue=%d)",
                nb_tx_to_clean, last_desc_cleaned, desc_to_clean_to,
                txq->port_id, txq->queue_id);

        /*
         * The last descriptor to clean is done, so that means all the
         * descriptors from the last descriptor that was cleaned
         * up to the last descriptor with the RS bit set
         * are done. Only reset the threshold descriptor.
         */
        txr[desc_to_clean_to].dw3 = 0;

        /* Update the txq to reflect the last descriptor that was cleaned */
        txq->last_desc_cleaned = desc_to_clean_to;
        txq->nb_tx_free = (uint16_t)(txq->nb_tx_free + nb_tx_to_clean);

        /* No Error */
        return 0;
}

uint16_t
ngbe_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
                uint16_t nb_pkts)
{
        struct ngbe_tx_queue *txq;
        struct ngbe_tx_entry *sw_ring;
        struct ngbe_tx_entry *txe, *txn;
        volatile struct ngbe_tx_desc *txr;
        volatile struct ngbe_tx_desc *txd;
        struct rte_mbuf     *tx_pkt;
        struct rte_mbuf     *m_seg;
        uint64_t buf_dma_addr;
        uint32_t olinfo_status;
        uint32_t cmd_type_len;
        uint32_t pkt_len;
        uint16_t slen;
        uint64_t ol_flags;
        uint16_t tx_id;
        uint16_t tx_last;
        uint16_t nb_tx;
        uint16_t nb_used;
        uint64_t tx_ol_req;
        uint32_t ctx = 0;
        uint32_t new_ctx;
        union ngbe_tx_offload tx_offload;

        tx_offload.data[0] = 0;
        tx_offload.data[1] = 0;
        txq = tx_queue;
        sw_ring = txq->sw_ring;
        txr     = txq->tx_ring;
        tx_id   = txq->tx_tail;
        txe = &sw_ring[tx_id];

        /* Determine if the descriptor ring needs to be cleaned. */
        if (txq->nb_tx_free < txq->tx_free_thresh)
                ngbe_xmit_cleanup(txq);

        rte_prefetch0(&txe->mbuf->pool);

        /* Tx loop */
        for (nb_tx = 0; nb_tx < nb_pkts; nb_tx++) {
                new_ctx = 0;
                tx_pkt = *tx_pkts++;
                pkt_len = tx_pkt->pkt_len;

                /*
                 * Determine how many (if any) context descriptors
                 * are needed for offload functionality.
                 */
                ol_flags = tx_pkt->ol_flags;

                /* If hardware offload required */
                tx_ol_req = ol_flags & NGBE_TX_OFFLOAD_MASK;
                if (tx_ol_req) {
                        tx_offload.ptid = tx_desc_ol_flags_to_ptid(tx_ol_req,
                                        tx_pkt->packet_type);
                        tx_offload.l2_len = tx_pkt->l2_len;
                        tx_offload.l3_len = tx_pkt->l3_len;
                        tx_offload.l4_len = tx_pkt->l4_len;
                        tx_offload.tso_segsz = tx_pkt->tso_segsz;
                        tx_offload.outer_l2_len = tx_pkt->outer_l2_len;
                        tx_offload.outer_l3_len = tx_pkt->outer_l3_len;
                        tx_offload.outer_tun_len = 0;

                        /* If new context need be built or reuse the exist ctx*/
                        ctx = what_ctx_update(txq, tx_ol_req, tx_offload);
                        /* Only allocate context descriptor if required */
                        new_ctx = (ctx == NGBE_CTX_NUM);
                        ctx = txq->ctx_curr;
                }

                /*
                 * Keep track of how many descriptors are used this loop
                 * This will always be the number of segments + the number of
                 * Context descriptors required to transmit the packet
                 */
                nb_used = (uint16_t)(tx_pkt->nb_segs + new_ctx);

                /*
                 * The number of descriptors that must be allocated for a
                 * packet is the number of segments of that packet, plus 1
                 * Context Descriptor for the hardware offload, if any.
                 * Determine the last Tx descriptor to allocate in the Tx ring
                 * for the packet, starting from the current position (tx_id)
                 * in the ring.
                 */
                tx_last = (uint16_t)(tx_id + nb_used - 1);

                /* Circular ring */
                if (tx_last >= txq->nb_tx_desc)
                        tx_last = (uint16_t)(tx_last - txq->nb_tx_desc);

                PMD_TX_LOG(DEBUG, "port_id=%u queue_id=%u pktlen=%u"
                           " tx_first=%u tx_last=%u",
                           (uint16_t)txq->port_id,
                           (uint16_t)txq->queue_id,
                           (uint32_t)pkt_len,
                           (uint16_t)tx_id,
                           (uint16_t)tx_last);

                /*
                 * Make sure there are enough Tx descriptors available to
                 * transmit the entire packet.
                 * nb_used better be less than or equal to txq->tx_free_thresh
                 */
                if (nb_used > txq->nb_tx_free) {
                        PMD_TX_LOG(DEBUG,
                                "Not enough free Tx descriptors "
                                "nb_used=%4u nb_free=%4u "
                                "(port=%d queue=%d)",
                                nb_used, txq->nb_tx_free,
                                txq->port_id, txq->queue_id);

                        if (ngbe_xmit_cleanup(txq) != 0) {
                                /* Could not clean any descriptors */
                                if (nb_tx == 0)
                                        return 0;
                                goto end_of_tx;
                        }

                        /* nb_used better be <= txq->tx_free_thresh */
                        if (unlikely(nb_used > txq->tx_free_thresh)) {
                                PMD_TX_LOG(DEBUG,
                                        "The number of descriptors needed to "
                                        "transmit the packet exceeds the "
                                        "RS bit threshold. This will impact "
                                        "performance."
                                        "nb_used=%4u nb_free=%4u "
                                        "tx_free_thresh=%4u. "
                                        "(port=%d queue=%d)",
                                        nb_used, txq->nb_tx_free,
                                        txq->tx_free_thresh,
                                        txq->port_id, txq->queue_id);
                                /*
                                 * Loop here until there are enough Tx
                                 * descriptors or until the ring cannot be
                                 * cleaned.
                                 */
                                while (nb_used > txq->nb_tx_free) {
                                        if (ngbe_xmit_cleanup(txq) != 0) {
                                                /*
                                                 * Could not clean any
                                                 * descriptors
                                                 */
                                                if (nb_tx == 0)
                                                        return 0;
                                                goto end_of_tx;
                                        }
                                }
                        }
                }

                /*
                 * By now there are enough free Tx descriptors to transmit
                 * the packet.
                 */

                /*
                 * Set common flags of all Tx Data Descriptors.
                 *
                 * The following bits must be set in the first Data Descriptor
                 * and are ignored in the other ones:
                 *   - NGBE_TXD_FCS
                 *
                 * The following bits must only be set in the last Data
                 * Descriptor:
                 *   - NGBE_TXD_EOP
                 */
                cmd_type_len = NGBE_TXD_FCS;

                olinfo_status = 0;
                if (tx_ol_req) {
                        if (ol_flags & RTE_MBUF_F_TX_TCP_SEG) {
                                /* when TSO is on, paylen in descriptor is the
                                 * not the packet len but the tcp payload len
                                 */
                                pkt_len -= (tx_offload.l2_len +
                                        tx_offload.l3_len + tx_offload.l4_len);
                                pkt_len -=
                                        (tx_pkt->ol_flags & RTE_MBUF_F_TX_TUNNEL_MASK)
                                        ? tx_offload.outer_l2_len +
                                          tx_offload.outer_l3_len : 0;
                        }

                        /*
                         * Setup the Tx Context Descriptor if required
                         */
                        if (new_ctx) {
                                volatile struct ngbe_tx_ctx_desc *ctx_txd;

                                ctx_txd = (volatile struct ngbe_tx_ctx_desc *)
                                    &txr[tx_id];

                                txn = &sw_ring[txe->next_id];
                                rte_prefetch0(&txn->mbuf->pool);

                                if (txe->mbuf != NULL) {
                                        rte_pktmbuf_free_seg(txe->mbuf);
                                        txe->mbuf = NULL;
                                }

                                ngbe_set_xmit_ctx(txq, ctx_txd, tx_ol_req,
                                        tx_offload);

                                txe->last_id = tx_last;
                                tx_id = txe->next_id;
                                txe = txn;
                        }

                        /*
                         * Setup the Tx Data Descriptor,
                         * This path will go through
                         * whatever new/reuse the context descriptor
                         */
                        cmd_type_len  |= tx_desc_ol_flags_to_cmdtype(ol_flags);
                        olinfo_status |=
                                tx_desc_cksum_flags_to_olinfo(ol_flags);
                        olinfo_status |= NGBE_TXD_IDX(ctx);
                }

                olinfo_status |= NGBE_TXD_PAYLEN(pkt_len);

                m_seg = tx_pkt;
                do {
                        txd = &txr[tx_id];
                        txn = &sw_ring[txe->next_id];
                        rte_prefetch0(&txn->mbuf->pool);

                        if (txe->mbuf != NULL)
                                rte_pktmbuf_free_seg(txe->mbuf);
                        txe->mbuf = m_seg;

                        /*
                         * Set up Transmit Data Descriptor.
                         */
                        slen = m_seg->data_len;
                        buf_dma_addr = rte_mbuf_data_iova(m_seg);
                        txd->qw0 = rte_cpu_to_le_64(buf_dma_addr);
                        txd->dw2 = rte_cpu_to_le_32(cmd_type_len | slen);
                        txd->dw3 = rte_cpu_to_le_32(olinfo_status);
                        txe->last_id = tx_last;
                        tx_id = txe->next_id;
                        txe = txn;
                        m_seg = m_seg->next;
                } while (m_seg != NULL);

                /*
                 * The last packet data descriptor needs End Of Packet (EOP)
                 */
                cmd_type_len |= NGBE_TXD_EOP;
                txq->nb_tx_free = (uint16_t)(txq->nb_tx_free - nb_used);

                txd->dw2 |= rte_cpu_to_le_32(cmd_type_len);
        }

end_of_tx:

        rte_wmb();

        /*
         * Set the Transmit Descriptor Tail (TDT)
         */
        PMD_TX_LOG(DEBUG, "port_id=%u queue_id=%u tx_tail=%u nb_tx=%u",
                   (uint16_t)txq->port_id, (uint16_t)txq->queue_id,
                   (uint16_t)tx_id, (uint16_t)nb_tx);
        ngbe_set32_relaxed(txq->tdt_reg_addr, tx_id);
        txq->tx_tail = tx_id;

        return nb_tx;
}

/*********************************************************************
 *
 *  Tx prep functions
 *
 **********************************************************************/
uint16_t
ngbe_prep_pkts(void *tx_queue, struct rte_mbuf **tx_pkts, uint16_t nb_pkts)
{
        int i, ret;
        uint64_t ol_flags;
        struct rte_mbuf *m;
        struct ngbe_tx_queue *txq = (struct ngbe_tx_queue *)tx_queue;

        for (i = 0; i < nb_pkts; i++) {
                m = tx_pkts[i];
                ol_flags = m->ol_flags;

                /**
                 * Check if packet meets requirements for number of segments
                 *
                 * NOTE: for ngbe it's always (40 - WTHRESH) for both TSO and
                 *       non-TSO
                 */

                if (m->nb_segs > NGBE_TX_MAX_SEG - txq->wthresh) {
                        rte_errno = -EINVAL;
                        return i;
                }

                if (ol_flags & NGBE_TX_OFFLOAD_NOTSUP_MASK) {
                        rte_errno = -ENOTSUP;
                        return i;
                }

#ifdef RTE_ETHDEV_DEBUG_TX
                ret = rte_validate_tx_offload(m);
                if (ret != 0) {
                        rte_errno = ret;
                        return i;
                }
#endif
                ret = rte_net_intel_cksum_prepare(m);
                if (ret != 0) {
                        rte_errno = ret;
                        return i;
                }
        }

        return i;
}

/*********************************************************************
 *
 *  Rx functions
 *
 **********************************************************************/
static inline uint32_t
ngbe_rxd_pkt_info_to_pkt_type(uint32_t pkt_info, uint16_t ptid_mask)
{
        uint16_t ptid = NGBE_RXD_PTID(pkt_info);

        ptid &= ptid_mask;

        return ngbe_decode_ptype(ptid);
}

static inline uint64_t
rx_desc_error_to_pkt_flags(uint32_t rx_status)
{
        uint64_t pkt_flags = 0;

        /* checksum offload can't be disabled */
        if (rx_status & NGBE_RXD_STAT_IPCS)
                pkt_flags |= (rx_status & NGBE_RXD_ERR_IPCS
                                ? RTE_MBUF_F_RX_IP_CKSUM_BAD : RTE_MBUF_F_RX_IP_CKSUM_GOOD);

        if (rx_status & NGBE_RXD_STAT_L4CS)
                pkt_flags |= (rx_status & NGBE_RXD_ERR_L4CS
                                ? RTE_MBUF_F_RX_L4_CKSUM_BAD : RTE_MBUF_F_RX_L4_CKSUM_GOOD);

        if (rx_status & NGBE_RXD_STAT_EIPCS &&
            rx_status & NGBE_RXD_ERR_EIPCS)
                pkt_flags |= RTE_MBUF_F_RX_OUTER_IP_CKSUM_BAD;

        return pkt_flags;
}

/*
 * LOOK_AHEAD defines how many desc statuses to check beyond the
 * current descriptor.
 * It must be a pound define for optimal performance.
 * Do not change the value of LOOK_AHEAD, as the ngbe_rx_scan_hw_ring
 * function only works with LOOK_AHEAD=8.
 */
#define LOOK_AHEAD 8
#if (LOOK_AHEAD != 8)
#error "PMD NGBE: LOOK_AHEAD must be 8\n"
#endif
static inline int
ngbe_rx_scan_hw_ring(struct ngbe_rx_queue *rxq)
{
        volatile struct ngbe_rx_desc *rxdp;
        struct ngbe_rx_entry *rxep;
        struct rte_mbuf *mb;
        uint16_t pkt_len;
        uint64_t pkt_flags;
        int nb_dd;
        uint32_t s[LOOK_AHEAD];
        uint32_t pkt_info[LOOK_AHEAD];
        int i, j, nb_rx = 0;
        uint32_t status;

        /* get references to current descriptor and S/W ring entry */
        rxdp = &rxq->rx_ring[rxq->rx_tail];
        rxep = &rxq->sw_ring[rxq->rx_tail];

        status = rxdp->qw1.lo.status;
        /* check to make sure there is at least 1 packet to receive */
        if (!(status & rte_cpu_to_le_32(NGBE_RXD_STAT_DD)))
                return 0;

        /*
         * Scan LOOK_AHEAD descriptors at a time to determine which descriptors
         * reference packets that are ready to be received.
         */
        for (i = 0; i < RTE_PMD_NGBE_RX_MAX_BURST;
             i += LOOK_AHEAD, rxdp += LOOK_AHEAD, rxep += LOOK_AHEAD) {
                /* Read desc statuses backwards to avoid race condition */
                for (j = 0; j < LOOK_AHEAD; j++)
                        s[j] = rte_le_to_cpu_32(rxdp[j].qw1.lo.status);

                rte_atomic_thread_fence(__ATOMIC_ACQUIRE);

                /* Compute how many status bits were set */
                for (nb_dd = 0; nb_dd < LOOK_AHEAD &&
                                (s[nb_dd] & NGBE_RXD_STAT_DD); nb_dd++)
                        ;

                for (j = 0; j < nb_dd; j++)
                        pkt_info[j] = rte_le_to_cpu_32(rxdp[j].qw0.dw0);

                nb_rx += nb_dd;

                /* Translate descriptor info to mbuf format */
                for (j = 0; j < nb_dd; ++j) {
                        mb = rxep[j].mbuf;
                        pkt_len = rte_le_to_cpu_16(rxdp[j].qw1.hi.len) -
                                  rxq->crc_len;
                        mb->data_len = pkt_len;
                        mb->pkt_len = pkt_len;

                        /* convert descriptor fields to rte mbuf flags */
                        pkt_flags = rx_desc_error_to_pkt_flags(s[j]);
                        mb->ol_flags = pkt_flags;
                        mb->packet_type =
                                ngbe_rxd_pkt_info_to_pkt_type(pkt_info[j],
                                NGBE_PTID_MASK);
                }

                /* Move mbuf pointers from the S/W ring to the stage */
                for (j = 0; j < LOOK_AHEAD; ++j)
                        rxq->rx_stage[i + j] = rxep[j].mbuf;

                /* stop if all requested packets could not be received */
                if (nb_dd != LOOK_AHEAD)
                        break;
        }

        /* clear software ring entries so we can cleanup correctly */
        for (i = 0; i < nb_rx; ++i)
                rxq->sw_ring[rxq->rx_tail + i].mbuf = NULL;

        return nb_rx;
}

static inline int
ngbe_rx_alloc_bufs(struct ngbe_rx_queue *rxq, bool reset_mbuf)
{
        volatile struct ngbe_rx_desc *rxdp;
        struct ngbe_rx_entry *rxep;
        struct rte_mbuf *mb;
        uint16_t alloc_idx;
        __le64 dma_addr;
        int diag, i;

        /* allocate buffers in bulk directly into the S/W ring */
        alloc_idx = rxq->rx_free_trigger - (rxq->rx_free_thresh - 1);
        rxep = &rxq->sw_ring[alloc_idx];
        diag = rte_mempool_get_bulk(rxq->mb_pool, (void *)rxep,
                                    rxq->rx_free_thresh);
        if (unlikely(diag != 0))
                return -ENOMEM;

        rxdp = &rxq->rx_ring[alloc_idx];
        for (i = 0; i < rxq->rx_free_thresh; ++i) {
                /* populate the static rte mbuf fields */
                mb = rxep[i].mbuf;
                if (reset_mbuf)
                        mb->port = rxq->port_id;

                rte_mbuf_refcnt_set(mb, 1);
                mb->data_off = RTE_PKTMBUF_HEADROOM;

                /* populate the descriptors */
                dma_addr = rte_cpu_to_le_64(rte_mbuf_data_iova_default(mb));
                NGBE_RXD_HDRADDR(&rxdp[i], 0);
                NGBE_RXD_PKTADDR(&rxdp[i], dma_addr);
        }

        /* update state of internal queue structure */
        rxq->rx_free_trigger = rxq->rx_free_trigger + rxq->rx_free_thresh;
        if (rxq->rx_free_trigger >= rxq->nb_rx_desc)
                rxq->rx_free_trigger = rxq->rx_free_thresh - 1;

        /* no errors */
        return 0;
}

static inline uint16_t
ngbe_rx_fill_from_stage(struct ngbe_rx_queue *rxq, struct rte_mbuf **rx_pkts,
                         uint16_t nb_pkts)
{
        struct rte_mbuf **stage = &rxq->rx_stage[rxq->rx_next_avail];
        int i;

        /* how many packets are ready to return? */
        nb_pkts = (uint16_t)RTE_MIN(nb_pkts, rxq->rx_nb_avail);

        /* copy mbuf pointers to the application's packet list */
        for (i = 0; i < nb_pkts; ++i)
                rx_pkts[i] = stage[i];

        /* update internal queue state */
        rxq->rx_nb_avail = (uint16_t)(rxq->rx_nb_avail - nb_pkts);
        rxq->rx_next_avail = (uint16_t)(rxq->rx_next_avail + nb_pkts);

        return nb_pkts;
}

static inline uint16_t
ngbe_rx_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
             uint16_t nb_pkts)
{
        struct ngbe_rx_queue *rxq = (struct ngbe_rx_queue *)rx_queue;
        struct rte_eth_dev *dev = &rte_eth_devices[rxq->port_id];
        uint16_t nb_rx = 0;

        /* Any previously recv'd pkts will be returned from the Rx stage */
        if (rxq->rx_nb_avail)
                return ngbe_rx_fill_from_stage(rxq, rx_pkts, nb_pkts);

        /* Scan the H/W ring for packets to receive */
        nb_rx = (uint16_t)ngbe_rx_scan_hw_ring(rxq);

        /* update internal queue state */
        rxq->rx_next_avail = 0;
        rxq->rx_nb_avail = nb_rx;
        rxq->rx_tail = (uint16_t)(rxq->rx_tail + nb_rx);

        /* if required, allocate new buffers to replenish descriptors */
        if (rxq->rx_tail > rxq->rx_free_trigger) {
                uint16_t cur_free_trigger = rxq->rx_free_trigger;

                if (ngbe_rx_alloc_bufs(rxq, true) != 0) {
                        int i, j;

                        PMD_RX_LOG(DEBUG, "RX mbuf alloc failed port_id=%u "
                                   "queue_id=%u", (uint16_t)rxq->port_id,
                                   (uint16_t)rxq->queue_id);

                        dev->data->rx_mbuf_alloc_failed +=
                                rxq->rx_free_thresh;

                        /*
                         * Need to rewind any previous receives if we cannot
                         * allocate new buffers to replenish the old ones.
                         */
                        rxq->rx_nb_avail = 0;
                        rxq->rx_tail = (uint16_t)(rxq->rx_tail - nb_rx);
                        for (i = 0, j = rxq->rx_tail; i < nb_rx; ++i, ++j)
                                rxq->sw_ring[j].mbuf = rxq->rx_stage[i];

                        return 0;
                }

                /* update tail pointer */
                rte_wmb();
                ngbe_set32_relaxed(rxq->rdt_reg_addr, cur_free_trigger);
        }

        if (rxq->rx_tail >= rxq->nb_rx_desc)
                rxq->rx_tail = 0;

        /* received any packets this loop? */
        if (rxq->rx_nb_avail)
                return ngbe_rx_fill_from_stage(rxq, rx_pkts, nb_pkts);

        return 0;
}

/* split requests into chunks of size RTE_PMD_NGBE_RX_MAX_BURST */
uint16_t
ngbe_recv_pkts_bulk_alloc(void *rx_queue, struct rte_mbuf **rx_pkts,
                           uint16_t nb_pkts)
{
        uint16_t nb_rx;

        if (unlikely(nb_pkts == 0))
                return 0;

        if (likely(nb_pkts <= RTE_PMD_NGBE_RX_MAX_BURST))
                return ngbe_rx_recv_pkts(rx_queue, rx_pkts, nb_pkts);

        /* request is relatively large, chunk it up */
        nb_rx = 0;
        while (nb_pkts) {
                uint16_t ret, n;

                n = (uint16_t)RTE_MIN(nb_pkts, RTE_PMD_NGBE_RX_MAX_BURST);
                ret = ngbe_rx_recv_pkts(rx_queue, &rx_pkts[nb_rx], n);
                nb_rx = (uint16_t)(nb_rx + ret);
                nb_pkts = (uint16_t)(nb_pkts - ret);
                if (ret < n)
                        break;
        }

        return nb_rx;
}

uint16_t
ngbe_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
                uint16_t nb_pkts)
{
        struct ngbe_rx_queue *rxq;
        volatile struct ngbe_rx_desc *rx_ring;
        volatile struct ngbe_rx_desc *rxdp;
        struct ngbe_rx_entry *sw_ring;
        struct ngbe_rx_entry *rxe;
        struct rte_mbuf *rxm;
        struct rte_mbuf *nmb;
        struct ngbe_rx_desc rxd;
        uint64_t dma_addr;
        uint32_t staterr;
        uint32_t pkt_info;
        uint16_t pkt_len;
        uint16_t rx_id;
        uint16_t nb_rx;
        uint16_t nb_hold;
        uint64_t pkt_flags;

        nb_rx = 0;
        nb_hold = 0;
        rxq = rx_queue;
        rx_id = rxq->rx_tail;
        rx_ring = rxq->rx_ring;
        sw_ring = rxq->sw_ring;
        struct rte_eth_dev *dev = &rte_eth_devices[rxq->port_id];
        while (nb_rx < nb_pkts) {
                /*
                 * The order of operations here is important as the DD status
                 * bit must not be read after any other descriptor fields.
                 * rx_ring and rxdp are pointing to volatile data so the order
                 * of accesses cannot be reordered by the compiler. If they were
                 * not volatile, they could be reordered which could lead to
                 * using invalid descriptor fields when read from rxd.
                 */
                rxdp = &rx_ring[rx_id];
                staterr = rxdp->qw1.lo.status;
                if (!(staterr & rte_cpu_to_le_32(NGBE_RXD_STAT_DD)))
                        break;
                rxd = *rxdp;

                /*
                 * End of packet.
                 *
                 * If the NGBE_RXD_STAT_EOP flag is not set, the Rx packet
                 * is likely to be invalid and to be dropped by the various
                 * validation checks performed by the network stack.
                 *
                 * Allocate a new mbuf to replenish the RX ring descriptor.
                 * If the allocation fails:
                 *    - arrange for that Rx descriptor to be the first one
                 *      being parsed the next time the receive function is
                 *      invoked [on the same queue].
                 *
                 *    - Stop parsing the Rx ring and return immediately.
                 *
                 * This policy do not drop the packet received in the Rx
                 * descriptor for which the allocation of a new mbuf failed.
                 * Thus, it allows that packet to be later retrieved if
                 * mbuf have been freed in the mean time.
                 * As a side effect, holding Rx descriptors instead of
                 * systematically giving them back to the NIC may lead to
                 * Rx ring exhaustion situations.
                 * However, the NIC can gracefully prevent such situations
                 * to happen by sending specific "back-pressure" flow control
                 * frames to its peer(s).
                 */
                PMD_RX_LOG(DEBUG,
                           "port_id=%u queue_id=%u rx_id=%u ext_err_stat=0x%08x pkt_len=%u",
                           (uint16_t)rxq->port_id, (uint16_t)rxq->queue_id,
                           (uint16_t)rx_id, (uint32_t)staterr,
                           (uint16_t)rte_le_to_cpu_16(rxd.qw1.hi.len));

                nmb = rte_mbuf_raw_alloc(rxq->mb_pool);
                if (nmb == NULL) {
                        PMD_RX_LOG(DEBUG,
                                   "Rx mbuf alloc failed port_id=%u queue_id=%u",
                                   (uint16_t)rxq->port_id,
                                   (uint16_t)rxq->queue_id);
                        dev->data->rx_mbuf_alloc_failed++;
                        break;
                }

                nb_hold++;
                rxe = &sw_ring[rx_id];
                rx_id++;
                if (rx_id == rxq->nb_rx_desc)
                        rx_id = 0;

                /* Prefetch next mbuf while processing current one. */
                rte_ngbe_prefetch(sw_ring[rx_id].mbuf);

                /*
                 * When next Rx descriptor is on a cache-line boundary,
                 * prefetch the next 4 Rx descriptors and the next 8 pointers
                 * to mbufs.
                 */
                if ((rx_id & 0x3) == 0) {
                        rte_ngbe_prefetch(&rx_ring[rx_id]);
                        rte_ngbe_prefetch(&sw_ring[rx_id]);
                }

                rxm = rxe->mbuf;
                rxe->mbuf = nmb;
                dma_addr = rte_cpu_to_le_64(rte_mbuf_data_iova_default(nmb));
                NGBE_RXD_HDRADDR(rxdp, 0);
                NGBE_RXD_PKTADDR(rxdp, dma_addr);

                /*
                 * Initialize the returned mbuf.
                 * 1) setup generic mbuf fields:
                 *    - number of segments,
                 *    - next segment,
                 *    - packet length,
                 *    - Rx port identifier.
                 * 2) integrate hardware offload data, if any:
                 *    - IP checksum flag,
                 *    - error flags.
                 */
                pkt_len = (uint16_t)(rte_le_to_cpu_16(rxd.qw1.hi.len) -
                                      rxq->crc_len);
                rxm->data_off = RTE_PKTMBUF_HEADROOM;
                rte_packet_prefetch((char *)rxm->buf_addr + rxm->data_off);
                rxm->nb_segs = 1;
                rxm->next = NULL;
                rxm->pkt_len = pkt_len;
                rxm->data_len = pkt_len;
                rxm->port = rxq->port_id;

                pkt_info = rte_le_to_cpu_32(rxd.qw0.dw0);
                pkt_flags = rx_desc_error_to_pkt_flags(staterr);
                rxm->ol_flags = pkt_flags;
                rxm->packet_type = ngbe_rxd_pkt_info_to_pkt_type(pkt_info,
                                                       NGBE_PTID_MASK);

                /*
                 * Store the mbuf address into the next entry of the array
                 * of returned packets.
                 */
                rx_pkts[nb_rx++] = rxm;
        }
        rxq->rx_tail = rx_id;

        /*
         * If the number of free Rx descriptors is greater than the Rx free
         * threshold of the queue, advance the Receive Descriptor Tail (RDT)
         * register.
         * Update the RDT with the value of the last processed Rx descriptor
         * minus 1, to guarantee that the RDT register is never equal to the
         * RDH register, which creates a "full" ring situation from the
         * hardware point of view...
         */
        nb_hold = (uint16_t)(nb_hold + rxq->nb_rx_hold);
        if (nb_hold > rxq->rx_free_thresh) {
                PMD_RX_LOG(DEBUG,
                           "port_id=%u queue_id=%u rx_tail=%u nb_hold=%u nb_rx=%u",
                           (uint16_t)rxq->port_id, (uint16_t)rxq->queue_id,
                           (uint16_t)rx_id, (uint16_t)nb_hold,
                           (uint16_t)nb_rx);
                rx_id = (uint16_t)((rx_id == 0) ?
                                (rxq->nb_rx_desc - 1) : (rx_id - 1));
                ngbe_set32(rxq->rdt_reg_addr, rx_id);
                nb_hold = 0;
        }
        rxq->nb_rx_hold = nb_hold;
        return nb_rx;
}

/**
 * ngbe_fill_cluster_head_buf - fill the first mbuf of the returned packet
 *
 * Fill the following info in the HEAD buffer of the Rx cluster:
 *    - RX port identifier
 *    - hardware offload data, if any:
 *      - IP checksum flag
 *      - error flags
 * @head HEAD of the packet cluster
 * @desc HW descriptor to get data from
 * @rxq Pointer to the Rx queue
 */
static inline void
ngbe_fill_cluster_head_buf(struct rte_mbuf *head, struct ngbe_rx_desc *desc,
                struct ngbe_rx_queue *rxq, uint32_t staterr)
{
        uint32_t pkt_info;
        uint64_t pkt_flags;

        head->port = rxq->port_id;

        pkt_info = rte_le_to_cpu_32(desc->qw0.dw0);
        pkt_flags = rx_desc_error_to_pkt_flags(staterr);
        head->ol_flags = pkt_flags;
        head->packet_type = ngbe_rxd_pkt_info_to_pkt_type(pkt_info,
                                                NGBE_PTID_MASK);
}

/**
 * ngbe_recv_pkts_sc - receive handler for scatter case.
 *
 * @rx_queue Rx queue handle
 * @rx_pkts table of received packets
 * @nb_pkts size of rx_pkts table
 * @bulk_alloc if TRUE bulk allocation is used for a HW ring refilling
 *
 * Returns the number of received packets/clusters (according to the "bulk
 * receive" interface).
 */
static inline uint16_t
ngbe_recv_pkts_sc(void *rx_queue, struct rte_mbuf **rx_pkts, uint16_t nb_pkts,
                    bool bulk_alloc)
{
        struct ngbe_rx_queue *rxq = rx_queue;
        struct rte_eth_dev *dev = &rte_eth_devices[rxq->port_id];
        volatile struct ngbe_rx_desc *rx_ring = rxq->rx_ring;
        struct ngbe_rx_entry *sw_ring = rxq->sw_ring;
        struct ngbe_scattered_rx_entry *sw_sc_ring = rxq->sw_sc_ring;
        uint16_t rx_id = rxq->rx_tail;
        uint16_t nb_rx = 0;
        uint16_t nb_hold = rxq->nb_rx_hold;
        uint16_t prev_id = rxq->rx_tail;

        while (nb_rx < nb_pkts) {
                bool eop;
                struct ngbe_rx_entry *rxe;
                struct ngbe_scattered_rx_entry *sc_entry;
                struct ngbe_scattered_rx_entry *next_sc_entry = NULL;
                struct ngbe_rx_entry *next_rxe = NULL;
                struct rte_mbuf *first_seg;
                struct rte_mbuf *rxm;
                struct rte_mbuf *nmb = NULL;
                struct ngbe_rx_desc rxd;
                uint16_t data_len;
                uint16_t next_id;
                volatile struct ngbe_rx_desc *rxdp;
                uint32_t staterr;

next_desc:
                rxdp = &rx_ring[rx_id];
                staterr = rte_le_to_cpu_32(rxdp->qw1.lo.status);

                if (!(staterr & NGBE_RXD_STAT_DD))
                        break;

                rxd = *rxdp;

                PMD_RX_LOG(DEBUG, "port_id=%u queue_id=%u rx_id=%u "
                                  "staterr=0x%x data_len=%u",
                           rxq->port_id, rxq->queue_id, rx_id, staterr,
                           rte_le_to_cpu_16(rxd.qw1.hi.len));

                if (!bulk_alloc) {
                        nmb = rte_mbuf_raw_alloc(rxq->mb_pool);
                        if (nmb == NULL) {
                                PMD_RX_LOG(DEBUG, "Rx mbuf alloc failed "
                                                  "port_id=%u queue_id=%u",
                                           rxq->port_id, rxq->queue_id);

                                dev->data->rx_mbuf_alloc_failed++;
                                break;
                        }
                } else if (nb_hold > rxq->rx_free_thresh) {
                        uint16_t next_rdt = rxq->rx_free_trigger;

                        if (!ngbe_rx_alloc_bufs(rxq, false)) {
                                rte_wmb();
                                ngbe_set32_relaxed(rxq->rdt_reg_addr,
                                                            next_rdt);
                                nb_hold -= rxq->rx_free_thresh;
                        } else {
                                PMD_RX_LOG(DEBUG, "Rx bulk alloc failed "
                                                  "port_id=%u queue_id=%u",
                                           rxq->port_id, rxq->queue_id);

                                dev->data->rx_mbuf_alloc_failed++;
                                break;
                        }
                }

                nb_hold++;
                rxe = &sw_ring[rx_id];
                eop = staterr & NGBE_RXD_STAT_EOP;

                next_id = rx_id + 1;
                if (next_id == rxq->nb_rx_desc)
                        next_id = 0;

                /* Prefetch next mbuf while processing current one. */
                rte_ngbe_prefetch(sw_ring[next_id].mbuf);

                /*
                 * When next Rx descriptor is on a cache-line boundary,
                 * prefetch the next 4 RX descriptors and the next 4 pointers
                 * to mbufs.
                 */
                if ((next_id & 0x3) == 0) {
                        rte_ngbe_prefetch(&rx_ring[next_id]);
                        rte_ngbe_prefetch(&sw_ring[next_id]);
                }

                rxm = rxe->mbuf;

                if (!bulk_alloc) {
                        __le64 dma =
                          rte_cpu_to_le_64(rte_mbuf_data_iova_default(nmb));
                        /*
                         * Update Rx descriptor with the physical address of the
                         * new data buffer of the new allocated mbuf.
                         */
                        rxe->mbuf = nmb;

                        rxm->data_off = RTE_PKTMBUF_HEADROOM;
                        NGBE_RXD_HDRADDR(rxdp, 0);
                        NGBE_RXD_PKTADDR(rxdp, dma);
                } else {
                        rxe->mbuf = NULL;
                }

                /*
                 * Set data length & data buffer address of mbuf.
                 */
                data_len = rte_le_to_cpu_16(rxd.qw1.hi.len);
                rxm->data_len = data_len;

                if (!eop) {
                        uint16_t nextp_id;

                        nextp_id = next_id;
                        next_sc_entry = &sw_sc_ring[nextp_id];
                        next_rxe = &sw_ring[nextp_id];
                        rte_ngbe_prefetch(next_rxe);
                }

                sc_entry = &sw_sc_ring[rx_id];
                first_seg = sc_entry->fbuf;
                sc_entry->fbuf = NULL;

                /*
                 * If this is the first buffer of the received packet,
                 * set the pointer to the first mbuf of the packet and
                 * initialize its context.
                 * Otherwise, update the total length and the number of segments
                 * of the current scattered packet, and update the pointer to
                 * the last mbuf of the current packet.
                 */
                if (first_seg == NULL) {
                        first_seg = rxm;
                        first_seg->pkt_len = data_len;
                        first_seg->nb_segs = 1;
                } else {
                        first_seg->pkt_len += data_len;
                        first_seg->nb_segs++;
                }

                prev_id = rx_id;
                rx_id = next_id;

                /*
                 * If this is not the last buffer of the received packet, update
                 * the pointer to the first mbuf at the NEXTP entry in the
                 * sw_sc_ring and continue to parse the Rx ring.
                 */
                if (!eop && next_rxe) {
                        rxm->next = next_rxe->mbuf;
                        next_sc_entry->fbuf = first_seg;
                        goto next_desc;
                }

                /* Initialize the first mbuf of the returned packet */
                ngbe_fill_cluster_head_buf(first_seg, &rxd, rxq, staterr);

                /* Deal with the case, when HW CRC srip is disabled. */
                first_seg->pkt_len -= rxq->crc_len;
                if (unlikely(rxm->data_len <= rxq->crc_len)) {
                        struct rte_mbuf *lp;

                        for (lp = first_seg; lp->next != rxm; lp = lp->next)
                                ;

                        first_seg->nb_segs--;
                        lp->data_len -= rxq->crc_len - rxm->data_len;
                        lp->next = NULL;
                        rte_pktmbuf_free_seg(rxm);
                } else {
                        rxm->data_len -= rxq->crc_len;
                }

                /* Prefetch data of first segment, if configured to do so. */
                rte_packet_prefetch((char *)first_seg->buf_addr +
                        first_seg->data_off);

                /*
                 * Store the mbuf address into the next entry of the array
                 * of returned packets.
                 */
                rx_pkts[nb_rx++] = first_seg;
        }

        /*
         * Record index of the next Rx descriptor to probe.
         */
        rxq->rx_tail = rx_id;

        /*
         * If the number of free Rx descriptors is greater than the Rx free
         * threshold of the queue, advance the Receive Descriptor Tail (RDT)
         * register.
         * Update the RDT with the value of the last processed Rx descriptor
         * minus 1, to guarantee that the RDT register is never equal to the
         * RDH register, which creates a "full" ring situation from the
         * hardware point of view...
         */
        if (!bulk_alloc && nb_hold > rxq->rx_free_thresh) {
                PMD_RX_LOG(DEBUG, "port_id=%u queue_id=%u rx_tail=%u "
                           "nb_hold=%u nb_rx=%u",
                           rxq->port_id, rxq->queue_id, rx_id, nb_hold, nb_rx);

                rte_wmb();
                ngbe_set32_relaxed(rxq->rdt_reg_addr, prev_id);
                nb_hold = 0;
        }

        rxq->nb_rx_hold = nb_hold;
        return nb_rx;
}

uint16_t
ngbe_recv_pkts_sc_single_alloc(void *rx_queue, struct rte_mbuf **rx_pkts,
                                 uint16_t nb_pkts)
{
        return ngbe_recv_pkts_sc(rx_queue, rx_pkts, nb_pkts, false);
}

uint16_t
ngbe_recv_pkts_sc_bulk_alloc(void *rx_queue, struct rte_mbuf **rx_pkts,
                               uint16_t nb_pkts)
{
        return ngbe_recv_pkts_sc(rx_queue, rx_pkts, nb_pkts, true);
}

/*********************************************************************
 *
 *  Queue management functions
 *
 **********************************************************************/

static void
ngbe_tx_queue_release_mbufs(struct ngbe_tx_queue *txq)
{
        unsigned int i;

        if (txq->sw_ring != NULL) {
                for (i = 0; i < txq->nb_tx_desc; i++) {
                        if (txq->sw_ring[i].mbuf != NULL) {
                                rte_pktmbuf_free_seg(txq->sw_ring[i].mbuf);
                                txq->sw_ring[i].mbuf = NULL;
                        }
                }
        }
}

static void
ngbe_tx_free_swring(struct ngbe_tx_queue *txq)
{
        if (txq != NULL)
                rte_free(txq->sw_ring);
}

static void
ngbe_tx_queue_release(struct ngbe_tx_queue *txq)
{
        if (txq != NULL) {
                if (txq->ops != NULL) {
                        txq->ops->release_mbufs(txq);
                        txq->ops->free_swring(txq);
                }
                rte_free(txq);
        }
}

void
ngbe_dev_tx_queue_release(struct rte_eth_dev *dev, uint16_t qid)
{
        ngbe_tx_queue_release(dev->data->tx_queues[qid]);
}

/* (Re)set dynamic ngbe_tx_queue fields to defaults */
static void
ngbe_reset_tx_queue(struct ngbe_tx_queue *txq)
{
        static const struct ngbe_tx_desc zeroed_desc = {0};
        struct ngbe_tx_entry *txe = txq->sw_ring;
        uint16_t prev, i;

        /* Zero out HW ring memory */
        for (i = 0; i < txq->nb_tx_desc; i++)
                txq->tx_ring[i] = zeroed_desc;

        /* Initialize SW ring entries */
        prev = (uint16_t)(txq->nb_tx_desc - 1);
        for (i = 0; i < txq->nb_tx_desc; i++) {
                /* the ring can also be modified by hardware */
                volatile struct ngbe_tx_desc *txd = &txq->tx_ring[i];

                txd->dw3 = rte_cpu_to_le_32(NGBE_TXD_DD);
                txe[i].mbuf = NULL;
                txe[i].last_id = i;
                txe[prev].next_id = i;
                prev = i;
        }

        txq->tx_next_dd = (uint16_t)(txq->tx_free_thresh - 1);
        txq->tx_tail = 0;

        /*
         * Always allow 1 descriptor to be un-allocated to avoid
         * a H/W race condition
         */
        txq->last_desc_cleaned = (uint16_t)(txq->nb_tx_desc - 1);
        txq->nb_tx_free = (uint16_t)(txq->nb_tx_desc - 1);
        txq->ctx_curr = 0;
        memset((void *)&txq->ctx_cache, 0,
                NGBE_CTX_NUM * sizeof(struct ngbe_ctx_info));
}

static const struct ngbe_txq_ops def_txq_ops = {
        .release_mbufs = ngbe_tx_queue_release_mbufs,
        .free_swring = ngbe_tx_free_swring,
        .reset = ngbe_reset_tx_queue,
};

/* Takes an ethdev and a queue and sets up the tx function to be used based on
 * the queue parameters. Used in tx_queue_setup by primary process and then
 * in dev_init by secondary process when attaching to an existing ethdev.
 */
void
ngbe_set_tx_function(struct rte_eth_dev *dev, struct ngbe_tx_queue *txq)
{
        /* Use a simple Tx queue (no offloads, no multi segs) if possible */
        if (txq->offloads == 0 &&
                        txq->tx_free_thresh >= RTE_PMD_NGBE_TX_MAX_BURST) {
                PMD_INIT_LOG(DEBUG, "Using simple tx code path");
                dev->tx_pkt_burst = ngbe_xmit_pkts_simple;
                dev->tx_pkt_prepare = NULL;
        } else {
                PMD_INIT_LOG(DEBUG, "Using full-featured tx code path");
                PMD_INIT_LOG(DEBUG,
                                " - offloads = 0x%" PRIx64,
                                txq->offloads);
                PMD_INIT_LOG(DEBUG,
                                " - tx_free_thresh = %lu [RTE_PMD_NGBE_TX_MAX_BURST=%lu]",
                                (unsigned long)txq->tx_free_thresh,
                                (unsigned long)RTE_PMD_NGBE_TX_MAX_BURST);
                dev->tx_pkt_burst = ngbe_xmit_pkts;
                dev->tx_pkt_prepare = ngbe_prep_pkts;
        }
}

static const struct {
        eth_tx_burst_t pkt_burst;
        const char *info;
} ngbe_tx_burst_infos[] = {
        { ngbe_xmit_pkts_simple,   "Scalar Simple"},
        { ngbe_xmit_pkts,          "Scalar"},
};

int
ngbe_tx_burst_mode_get(struct rte_eth_dev *dev, __rte_unused uint16_t queue_id,
                      struct rte_eth_burst_mode *mode)
{
        eth_tx_burst_t pkt_burst = dev->tx_pkt_burst;
        int ret = -EINVAL;
        unsigned int i;

        for (i = 0; i < RTE_DIM(ngbe_tx_burst_infos); ++i) {
                if (pkt_burst == ngbe_tx_burst_infos[i].pkt_burst) {
                        snprintf(mode->info, sizeof(mode->info), "%s",
                                 ngbe_tx_burst_infos[i].info);
                        ret = 0;
                        break;
                }
        }

        return ret;
}

uint64_t
ngbe_get_tx_port_offloads(struct rte_eth_dev *dev)
{
        uint64_t tx_offload_capa;

        RTE_SET_USED(dev);

        tx_offload_capa =
                RTE_ETH_TX_OFFLOAD_IPV4_CKSUM  |
                RTE_ETH_TX_OFFLOAD_UDP_CKSUM   |
                RTE_ETH_TX_OFFLOAD_TCP_CKSUM   |
                RTE_ETH_TX_OFFLOAD_SCTP_CKSUM  |
                RTE_ETH_TX_OFFLOAD_OUTER_IPV4_CKSUM |
                RTE_ETH_TX_OFFLOAD_TCP_TSO     |
                RTE_ETH_TX_OFFLOAD_UDP_TSO         |
                RTE_ETH_TX_OFFLOAD_UDP_TNL_TSO  |
                RTE_ETH_TX_OFFLOAD_IP_TNL_TSO   |
                RTE_ETH_TX_OFFLOAD_IPIP_TNL_TSO |
                RTE_ETH_TX_OFFLOAD_MULTI_SEGS;

        return tx_offload_capa;
}

int
ngbe_dev_tx_queue_setup(struct rte_eth_dev *dev,
                         uint16_t queue_idx,
                         uint16_t nb_desc,
                         unsigned int socket_id,
                         const struct rte_eth_txconf *tx_conf)
{
        const struct rte_memzone *tz;
        struct ngbe_tx_queue *txq;
        struct ngbe_hw     *hw;
        uint16_t tx_free_thresh;
        uint64_t offloads;

        PMD_INIT_FUNC_TRACE();
        hw = ngbe_dev_hw(dev);

        offloads = tx_conf->offloads | dev->data->dev_conf.txmode.offloads;

        /*
         * The Tx descriptor ring will be cleaned after txq->tx_free_thresh
         * descriptors are used or if the number of descriptors required
         * to transmit a packet is greater than the number of free Tx
         * descriptors.
         * One descriptor in the Tx ring is used as a sentinel to avoid a
         * H/W race condition, hence the maximum threshold constraints.
         * When set to zero use default values.
         */
        tx_free_thresh = (uint16_t)((tx_conf->tx_free_thresh) ?
                        tx_conf->tx_free_thresh : DEFAULT_TX_FREE_THRESH);
        if (tx_free_thresh >= (nb_desc - 3)) {
                PMD_INIT_LOG(ERR,
                             "tx_free_thresh must be less than the number of TX descriptors minus 3. (tx_free_thresh=%u port=%d queue=%d)",
                             (unsigned int)tx_free_thresh,
                             (int)dev->data->port_id, (int)queue_idx);
                return -(EINVAL);
        }

        if (nb_desc % tx_free_thresh != 0) {
                PMD_INIT_LOG(ERR,
                             "tx_free_thresh must be a divisor of the number of Tx descriptors. (tx_free_thresh=%u port=%d queue=%d)",
                             (unsigned int)tx_free_thresh,
                             (int)dev->data->port_id, (int)queue_idx);
                return -(EINVAL);
        }

        /* Free memory prior to re-allocation if needed... */
        if (dev->data->tx_queues[queue_idx] != NULL) {
                ngbe_tx_queue_release(dev->data->tx_queues[queue_idx]);
                dev->data->tx_queues[queue_idx] = NULL;
        }

        /* First allocate the Tx queue data structure */
        txq = rte_zmalloc_socket("ethdev Tx queue",
                                 sizeof(struct ngbe_tx_queue),
                                 RTE_CACHE_LINE_SIZE, socket_id);
        if (txq == NULL)
                return -ENOMEM;

        /*
         * Allocate Tx ring hardware descriptors. A memzone large enough to
         * handle the maximum ring size is allocated in order to allow for
         * resizing in later calls to the queue setup function.
         */
        tz = rte_eth_dma_zone_reserve(dev, "tx_ring", queue_idx,
                        sizeof(struct ngbe_tx_desc) * NGBE_RING_DESC_MAX,
                        NGBE_ALIGN, socket_id);
        if (tz == NULL) {
                ngbe_tx_queue_release(txq);
                return -ENOMEM;
        }

        txq->nb_tx_desc = nb_desc;
        txq->tx_free_thresh = tx_free_thresh;
        txq->pthresh = tx_conf->tx_thresh.pthresh;
        txq->hthresh = tx_conf->tx_thresh.hthresh;
        txq->wthresh = tx_conf->tx_thresh.wthresh;
        txq->queue_id = queue_idx;
        txq->reg_idx = queue_idx;
        txq->port_id = dev->data->port_id;
        txq->offloads = offloads;
        txq->ops = &def_txq_ops;
        txq->tx_deferred_start = tx_conf->tx_deferred_start;

        txq->tdt_reg_addr = NGBE_REG_ADDR(hw, NGBE_TXWP(txq->reg_idx));
        txq->tdc_reg_addr = NGBE_REG_ADDR(hw, NGBE_TXCFG(txq->reg_idx));

        txq->tx_ring_phys_addr = TMZ_PADDR(tz);
        txq->tx_ring = (struct ngbe_tx_desc *)TMZ_VADDR(tz);

        /* Allocate software ring */
        txq->sw_ring = rte_zmalloc_socket("txq->sw_ring",
                                sizeof(struct ngbe_tx_entry) * nb_desc,
                                RTE_CACHE_LINE_SIZE, socket_id);
        if (txq->sw_ring == NULL) {
                ngbe_tx_queue_release(txq);
                return -ENOMEM;
        }
        PMD_INIT_LOG(DEBUG,
                     "sw_ring=%p hw_ring=%p dma_addr=0x%" PRIx64,
                     txq->sw_ring, txq->tx_ring, txq->tx_ring_phys_addr);

        /* set up scalar Tx function as appropriate */
        ngbe_set_tx_function(dev, txq);

        txq->ops->reset(txq);

        dev->data->tx_queues[queue_idx] = txq;

        return 0;
}

/**
 * ngbe_free_sc_cluster - free the not-yet-completed scattered cluster
 *
 * The "next" pointer of the last segment of (not-yet-completed) RSC clusters
 * in the sw_sc_ring is not set to NULL but rather points to the next
 * mbuf of this RSC aggregation (that has not been completed yet and still
 * resides on the HW ring). So, instead of calling for rte_pktmbuf_free() we
 * will just free first "nb_segs" segments of the cluster explicitly by calling
 * an rte_pktmbuf_free_seg().
 *
 * @m scattered cluster head
 */
static void
ngbe_free_sc_cluster(struct rte_mbuf *m)
{
        uint16_t i, nb_segs = m->nb_segs;
        struct rte_mbuf *next_seg;

        for (i = 0; i < nb_segs; i++) {
                next_seg = m->next;
                rte_pktmbuf_free_seg(m);
                m = next_seg;
        }
}

static void
ngbe_rx_queue_release_mbufs(struct ngbe_rx_queue *rxq)
{
        unsigned int i;

        if (rxq->sw_ring != NULL) {
                for (i = 0; i < rxq->nb_rx_desc; i++) {
                        if (rxq->sw_ring[i].mbuf != NULL) {
                                rte_pktmbuf_free_seg(rxq->sw_ring[i].mbuf);
                                rxq->sw_ring[i].mbuf = NULL;
                        }
                }
                for (i = 0; i < rxq->rx_nb_avail; ++i) {
                        struct rte_mbuf *mb;

                        mb = rxq->rx_stage[rxq->rx_next_avail + i];
                        rte_pktmbuf_free_seg(mb);
                }
                rxq->rx_nb_avail = 0;
        }

        if (rxq->sw_sc_ring != NULL)
                for (i = 0; i < rxq->nb_rx_desc; i++)
                        if (rxq->sw_sc_ring[i].fbuf != NULL) {
                                ngbe_free_sc_cluster(rxq->sw_sc_ring[i].fbuf);
                                rxq->sw_sc_ring[i].fbuf = NULL;
                        }
}

static void
ngbe_rx_queue_release(struct ngbe_rx_queue *rxq)
{
        if (rxq != NULL) {
                ngbe_rx_queue_release_mbufs(rxq);
                rte_free(rxq->sw_ring);
                rte_free(rxq->sw_sc_ring);
                rte_free(rxq);
        }
}

void
ngbe_dev_rx_queue_release(struct rte_eth_dev *dev, uint16_t qid)
{
        ngbe_rx_queue_release(dev->data->rx_queues[qid]);
}

/*
 * Check if Rx Burst Bulk Alloc function can be used.
 * Return
 *        0: the preconditions are satisfied and the bulk allocation function
 *           can be used.
 *  -EINVAL: the preconditions are NOT satisfied and the default Rx burst
 *           function must be used.
 */
static inline int
check_rx_burst_bulk_alloc_preconditions(struct ngbe_rx_queue *rxq)
{
        int ret = 0;

        /*
         * Make sure the following pre-conditions are satisfied:
         *   rxq->rx_free_thresh >= RTE_PMD_NGBE_RX_MAX_BURST
         *   rxq->rx_free_thresh < rxq->nb_rx_desc
         *   (rxq->nb_rx_desc % rxq->rx_free_thresh) == 0
         * Scattered packets are not supported.  This should be checked
         * outside of this function.
         */
        if (rxq->rx_free_thresh < RTE_PMD_NGBE_RX_MAX_BURST) {
                PMD_INIT_LOG(DEBUG,
                             "Rx Burst Bulk Alloc Preconditions: rxq->rx_free_thresh=%d, RTE_PMD_NGBE_RX_MAX_BURST=%d",
                             rxq->rx_free_thresh, RTE_PMD_NGBE_RX_MAX_BURST);
                ret = -EINVAL;
        } else if (rxq->rx_free_thresh >= rxq->nb_rx_desc) {
                PMD_INIT_LOG(DEBUG,
                             "Rx Burst Bulk Alloc Preconditions: rxq->rx_free_thresh=%d, rxq->nb_rx_desc=%d",
                             rxq->rx_free_thresh, rxq->nb_rx_desc);
                ret = -EINVAL;
        } else if ((rxq->nb_rx_desc % rxq->rx_free_thresh) != 0) {
                PMD_INIT_LOG(DEBUG,
                             "Rx Burst Bulk Alloc Preconditions: rxq->nb_rx_desc=%d, rxq->rx_free_thresh=%d",
                             rxq->nb_rx_desc, rxq->rx_free_thresh);
                ret = -EINVAL;
        }

        return ret;
}

/* Reset dynamic ngbe_rx_queue fields back to defaults */
static void
ngbe_reset_rx_queue(struct ngbe_adapter *adapter, struct ngbe_rx_queue *rxq)
{
        static const struct ngbe_rx_desc zeroed_desc = {
                                                {{0}, {0} }, {{0}, {0} } };
        unsigned int i;
        uint16_t len = rxq->nb_rx_desc;

        /*
         * By default, the Rx queue setup function allocates enough memory for
         * NGBE_RING_DESC_MAX.  The Rx Burst bulk allocation function requires
         * extra memory at the end of the descriptor ring to be zero'd out.
         */
        if (adapter->rx_bulk_alloc_allowed)
                /* zero out extra memory */
                len += RTE_PMD_NGBE_RX_MAX_BURST;

        /*
         * Zero out HW ring memory. Zero out extra memory at the end of
         * the H/W ring so look-ahead logic in Rx Burst bulk alloc function
         * reads extra memory as zeros.
         */
        for (i = 0; i < len; i++)
                rxq->rx_ring[i] = zeroed_desc;

        /*
         * initialize extra software ring entries. Space for these extra
         * entries is always allocated
         */
        memset(&rxq->fake_mbuf, 0x0, sizeof(rxq->fake_mbuf));
        for (i = rxq->nb_rx_desc; i < len; ++i)
                rxq->sw_ring[i].mbuf = &rxq->fake_mbuf;

        rxq->rx_nb_avail = 0;
        rxq->rx_next_avail = 0;
        rxq->rx_free_trigger = (uint16_t)(rxq->rx_free_thresh - 1);
        rxq->rx_tail = 0;
        rxq->nb_rx_hold = 0;
        rxq->pkt_first_seg = NULL;
        rxq->pkt_last_seg = NULL;
}

uint64_t
ngbe_get_rx_port_offloads(struct rte_eth_dev *dev __rte_unused)
{
        uint64_t offloads;

        offloads = RTE_ETH_RX_OFFLOAD_IPV4_CKSUM  |
                   RTE_ETH_RX_OFFLOAD_UDP_CKSUM   |
                   RTE_ETH_RX_OFFLOAD_TCP_CKSUM   |
                   RTE_ETH_RX_OFFLOAD_KEEP_CRC    |
                   RTE_ETH_RX_OFFLOAD_SCATTER;

        return offloads;
}

int
ngbe_dev_rx_queue_setup(struct rte_eth_dev *dev,
                         uint16_t queue_idx,
                         uint16_t nb_desc,
                         unsigned int socket_id,
                         const struct rte_eth_rxconf *rx_conf,
                         struct rte_mempool *mp)
{
        const struct rte_memzone *rz;
        struct ngbe_rx_queue *rxq;
        struct ngbe_hw     *hw;
        uint16_t len;
        struct ngbe_adapter *adapter = ngbe_dev_adapter(dev);

        PMD_INIT_FUNC_TRACE();
        hw = ngbe_dev_hw(dev);

        /* Free memory prior to re-allocation if needed... */
        if (dev->data->rx_queues[queue_idx] != NULL) {
                ngbe_rx_queue_release(dev->data->rx_queues[queue_idx]);
                dev->data->rx_queues[queue_idx] = NULL;
        }

        /* First allocate the Rx queue data structure */
        rxq = rte_zmalloc_socket("ethdev RX queue",
                                 sizeof(struct ngbe_rx_queue),
                                 RTE_CACHE_LINE_SIZE, socket_id);
        if (rxq == NULL)
                return -ENOMEM;
        rxq->mb_pool = mp;
        rxq->nb_rx_desc = nb_desc;
        rxq->rx_free_thresh = rx_conf->rx_free_thresh;
        rxq->queue_id = queue_idx;
        rxq->reg_idx = queue_idx;
        rxq->port_id = dev->data->port_id;
        if (dev->data->dev_conf.rxmode.offloads & RTE_ETH_RX_OFFLOAD_KEEP_CRC)
                rxq->crc_len = RTE_ETHER_CRC_LEN;
        else
                rxq->crc_len = 0;
        rxq->drop_en = rx_conf->rx_drop_en;
        rxq->rx_deferred_start = rx_conf->rx_deferred_start;

        /*
         * Allocate Rx ring hardware descriptors. A memzone large enough to
         * handle the maximum ring size is allocated in order to allow for
         * resizing in later calls to the queue setup function.
         */
        rz = rte_eth_dma_zone_reserve(dev, "rx_ring", queue_idx,
                                      RX_RING_SZ, NGBE_ALIGN, socket_id);
        if (rz == NULL) {
                ngbe_rx_queue_release(rxq);
                return -ENOMEM;
        }

        /*
         * Zero init all the descriptors in the ring.
         */
        memset(rz->addr, 0, RX_RING_SZ);

        rxq->rdt_reg_addr = NGBE_REG_ADDR(hw, NGBE_RXWP(rxq->reg_idx));
        rxq->rdh_reg_addr = NGBE_REG_ADDR(hw, NGBE_RXRP(rxq->reg_idx));

        rxq->rx_ring_phys_addr = TMZ_PADDR(rz);
        rxq->rx_ring = (struct ngbe_rx_desc *)TMZ_VADDR(rz);

        /*
         * Certain constraints must be met in order to use the bulk buffer
         * allocation Rx burst function. If any of Rx queues doesn't meet them
         * the feature should be disabled for the whole port.
         */
        if (check_rx_burst_bulk_alloc_preconditions(rxq)) {
                PMD_INIT_LOG(DEBUG,
                             "queue[%d] doesn't meet Rx Bulk Alloc preconditions - canceling the feature for the whole port[%d]",
                             rxq->queue_id, rxq->port_id);
                adapter->rx_bulk_alloc_allowed = false;
        }

        /*
         * Allocate software ring. Allow for space at the end of the
         * S/W ring to make sure look-ahead logic in bulk alloc Rx burst
         * function does not access an invalid memory region.
         */
        len = nb_desc;
        if (adapter->rx_bulk_alloc_allowed)
                len += RTE_PMD_NGBE_RX_MAX_BURST;

        rxq->sw_ring = rte_zmalloc_socket("rxq->sw_ring",
                                          sizeof(struct ngbe_rx_entry) * len,
                                          RTE_CACHE_LINE_SIZE, socket_id);
        if (rxq->sw_ring == NULL) {
                ngbe_rx_queue_release(rxq);
                return -ENOMEM;
        }

        /*
         * Always allocate even if it's not going to be needed in order to
         * simplify the code.
         *
         * This ring is used in Scattered Rx cases and Scattered Rx may
         * be requested in ngbe_dev_rx_init(), which is called later from
         * dev_start() flow.
         */
        rxq->sw_sc_ring =
                rte_zmalloc_socket("rxq->sw_sc_ring",
                                  sizeof(struct ngbe_scattered_rx_entry) * len,
                                  RTE_CACHE_LINE_SIZE, socket_id);
        if (rxq->sw_sc_ring == NULL) {
                ngbe_rx_queue_release(rxq);
                return -ENOMEM;
        }

        PMD_INIT_LOG(DEBUG,
                     "sw_ring=%p sw_sc_ring=%p hw_ring=%p dma_addr=0x%" PRIx64,
                     rxq->sw_ring, rxq->sw_sc_ring, rxq->rx_ring,
                     rxq->rx_ring_phys_addr);

        dev->data->rx_queues[queue_idx] = rxq;

        ngbe_reset_rx_queue(adapter, rxq);

        return 0;
}

void
ngbe_dev_clear_queues(struct rte_eth_dev *dev)
{
        unsigned int i;
        struct ngbe_adapter *adapter = ngbe_dev_adapter(dev);

        PMD_INIT_FUNC_TRACE();

        for (i = 0; i < dev->data->nb_tx_queues; i++) {
                struct ngbe_tx_queue *txq = dev->data->tx_queues[i];

                if (txq != NULL) {
                        txq->ops->release_mbufs(txq);
                        txq->ops->reset(txq);
                }
        }

        for (i = 0; i < dev->data->nb_rx_queues; i++) {
                struct ngbe_rx_queue *rxq = dev->data->rx_queues[i];

                if (rxq != NULL) {
                        ngbe_rx_queue_release_mbufs(rxq);
                        ngbe_reset_rx_queue(adapter, rxq);
                }
        }
}

void
ngbe_dev_free_queues(struct rte_eth_dev *dev)
{
        unsigned int i;

        PMD_INIT_FUNC_TRACE();

        for (i = 0; i < dev->data->nb_rx_queues; i++) {
                ngbe_dev_rx_queue_release(dev, i);
                dev->data->rx_queues[i] = NULL;
        }
        dev->data->nb_rx_queues = 0;

        for (i = 0; i < dev->data->nb_tx_queues; i++) {
                ngbe_dev_tx_queue_release(dev, i);
                dev->data->tx_queues[i] = NULL;
        }
        dev->data->nb_tx_queues = 0;
}

static int
ngbe_alloc_rx_queue_mbufs(struct ngbe_rx_queue *rxq)
{
        struct ngbe_rx_entry *rxe = rxq->sw_ring;
        uint64_t dma_addr;
        unsigned int i;

        /* Initialize software ring entries */
        for (i = 0; i < rxq->nb_rx_desc; i++) {
                /* the ring can also be modified by hardware */
                volatile struct ngbe_rx_desc *rxd;
                struct rte_mbuf *mbuf = rte_mbuf_raw_alloc(rxq->mb_pool);

                if (mbuf == NULL) {
                        PMD_INIT_LOG(ERR, "Rx mbuf alloc failed queue_id=%u port_id=%u",
                                     (unsigned int)rxq->queue_id,
                                     (unsigned int)rxq->port_id);
                        return -ENOMEM;
                }

                mbuf->data_off = RTE_PKTMBUF_HEADROOM;
                mbuf->port = rxq->port_id;

                dma_addr =
                        rte_cpu_to_le_64(rte_mbuf_data_iova_default(mbuf));
                rxd = &rxq->rx_ring[i];
                NGBE_RXD_HDRADDR(rxd, 0);
                NGBE_RXD_PKTADDR(rxd, dma_addr);
                rxe[i].mbuf = mbuf;
        }

        return 0;
}

void
ngbe_set_rx_function(struct rte_eth_dev *dev)
{
        struct ngbe_adapter *adapter = ngbe_dev_adapter(dev);

        if (dev->data->scattered_rx) {
                /*
                 * Set the scattered callback: there are bulk and
                 * single allocation versions.
                 */
                if (adapter->rx_bulk_alloc_allowed) {
                        PMD_INIT_LOG(DEBUG, "Using a Scattered with bulk "
                                           "allocation callback (port=%d).",
                                     dev->data->port_id);
                        dev->rx_pkt_burst = ngbe_recv_pkts_sc_bulk_alloc;
                } else {
                        PMD_INIT_LOG(DEBUG, "Using Regular (non-vector, "
                                            "single allocation) "
                                            "Scattered Rx callback "
                                            "(port=%d).",
                                     dev->data->port_id);

                        dev->rx_pkt_burst = ngbe_recv_pkts_sc_single_alloc;
                }
        /*
         * Below we set "simple" callbacks according to port/queues parameters.
         * If parameters allow we are going to choose between the following
         * callbacks:
         *    - Bulk Allocation
         *    - Single buffer allocation (the simplest one)
         */
        } else if (adapter->rx_bulk_alloc_allowed) {
                PMD_INIT_LOG(DEBUG, "Rx Burst Bulk Alloc Preconditions are "
                                    "satisfied. Rx Burst Bulk Alloc function "
                                    "will be used on port=%d.",
                             dev->data->port_id);

                dev->rx_pkt_burst = ngbe_recv_pkts_bulk_alloc;
        } else {
                PMD_INIT_LOG(DEBUG, "Rx Burst Bulk Alloc Preconditions are not "
                                    "satisfied, or Scattered Rx is requested "
                                    "(port=%d).",
                             dev->data->port_id);

                dev->rx_pkt_burst = ngbe_recv_pkts;
        }
}

static const struct {
        eth_rx_burst_t pkt_burst;
        const char *info;
} ngbe_rx_burst_infos[] = {
        { ngbe_recv_pkts_sc_single_alloc,    "Scalar Scattered"},
        { ngbe_recv_pkts_sc_bulk_alloc,      "Scalar Scattered Bulk Alloc"},
        { ngbe_recv_pkts_bulk_alloc,         "Scalar Bulk Alloc"},
        { ngbe_recv_pkts,                    "Scalar"},
};

int
ngbe_rx_burst_mode_get(struct rte_eth_dev *dev, __rte_unused uint16_t queue_id,
                      struct rte_eth_burst_mode *mode)
{
        eth_rx_burst_t pkt_burst = dev->rx_pkt_burst;
        int ret = -EINVAL;
        unsigned int i;

        for (i = 0; i < RTE_DIM(ngbe_rx_burst_infos); ++i) {
                if (pkt_burst == ngbe_rx_burst_infos[i].pkt_burst) {
                        snprintf(mode->info, sizeof(mode->info), "%s",
                                 ngbe_rx_burst_infos[i].info);
                        ret = 0;
                        break;
                }
        }

        return ret;
}

/*
 * Initializes Receive Unit.
 */
int
ngbe_dev_rx_init(struct rte_eth_dev *dev)
{
        struct ngbe_hw *hw;
        struct ngbe_rx_queue *rxq;
        uint64_t bus_addr;
        uint32_t fctrl;
        uint32_t hlreg0;
        uint32_t srrctl;
        uint32_t rdrxctl;
        uint32_t rxcsum;
        uint16_t buf_size;
        uint16_t i;
        struct rte_eth_rxmode *rx_conf = &dev->data->dev_conf.rxmode;

        PMD_INIT_FUNC_TRACE();
        hw = ngbe_dev_hw(dev);

        /*
         * Make sure receives are disabled while setting
         * up the Rx context (registers, descriptor rings, etc.).
         */
        wr32m(hw, NGBE_MACRXCFG, NGBE_MACRXCFG_ENA, 0);
        wr32m(hw, NGBE_PBRXCTL, NGBE_PBRXCTL_ENA, 0);

        /* Enable receipt of broadcasted frames */
        fctrl = rd32(hw, NGBE_PSRCTL);
        fctrl |= NGBE_PSRCTL_BCA;
        wr32(hw, NGBE_PSRCTL, fctrl);

        /*
         * Configure CRC stripping, if any.
         */
        hlreg0 = rd32(hw, NGBE_SECRXCTL);
        if (rx_conf->offloads & RTE_ETH_RX_OFFLOAD_KEEP_CRC)
                hlreg0 &= ~NGBE_SECRXCTL_CRCSTRIP;
        else
                hlreg0 |= NGBE_SECRXCTL_CRCSTRIP;
        hlreg0 &= ~NGBE_SECRXCTL_XDSA;
        wr32(hw, NGBE_SECRXCTL, hlreg0);

        /*
         * Configure jumbo frame support, if any.
         */
        wr32m(hw, NGBE_FRMSZ, NGBE_FRMSZ_MAX_MASK,
                NGBE_FRMSZ_MAX(dev->data->mtu + NGBE_ETH_OVERHEAD));

        /* Setup Rx queues */
        for (i = 0; i < dev->data->nb_rx_queues; i++) {
                rxq = dev->data->rx_queues[i];

                /*
                 * Reset crc_len in case it was changed after queue setup by a
                 * call to configure.
                 */
                if (rx_conf->offloads & RTE_ETH_RX_OFFLOAD_KEEP_CRC)
                        rxq->crc_len = RTE_ETHER_CRC_LEN;
                else
                        rxq->crc_len = 0;

                /* Setup the Base and Length of the Rx Descriptor Rings */
                bus_addr = rxq->rx_ring_phys_addr;
                wr32(hw, NGBE_RXBAL(rxq->reg_idx),
                                (uint32_t)(bus_addr & BIT_MASK32));
                wr32(hw, NGBE_RXBAH(rxq->reg_idx),
                                (uint32_t)(bus_addr >> 32));
                wr32(hw, NGBE_RXRP(rxq->reg_idx), 0);
                wr32(hw, NGBE_RXWP(rxq->reg_idx), 0);

                srrctl = NGBE_RXCFG_RNGLEN(rxq->nb_rx_desc);

                /* Set if packets are dropped when no descriptors available */
                if (rxq->drop_en)
                        srrctl |= NGBE_RXCFG_DROP;

                /*
                 * Configure the Rx buffer size in the PKTLEN field of
                 * the RXCFG register of the queue.
                 * The value is in 1 KB resolution. Valid values can be from
                 * 1 KB to 16 KB.
                 */
                buf_size = (uint16_t)(rte_pktmbuf_data_room_size(rxq->mb_pool) -
                        RTE_PKTMBUF_HEADROOM);
                buf_size = ROUND_DOWN(buf_size, 0x1 << 10);
                srrctl |= NGBE_RXCFG_PKTLEN(buf_size);

                wr32(hw, NGBE_RXCFG(rxq->reg_idx), srrctl);
        }

        if (rx_conf->offloads & RTE_ETH_RX_OFFLOAD_SCATTER)
                dev->data->scattered_rx = 1;
        /*
         * Setup the Checksum Register.
         * Enable IP/L4 checksum computation by hardware if requested to do so.
         */
        rxcsum = rd32(hw, NGBE_PSRCTL);
        rxcsum |= NGBE_PSRCTL_PCSD;
        if (rx_conf->offloads & RTE_ETH_RX_OFFLOAD_CHECKSUM)
                rxcsum |= NGBE_PSRCTL_L4CSUM;
        else
                rxcsum &= ~NGBE_PSRCTL_L4CSUM;

        wr32(hw, NGBE_PSRCTL, rxcsum);

        if (hw->is_pf) {
                rdrxctl = rd32(hw, NGBE_SECRXCTL);
                if (rx_conf->offloads & RTE_ETH_RX_OFFLOAD_KEEP_CRC)
                        rdrxctl &= ~NGBE_SECRXCTL_CRCSTRIP;
                else
                        rdrxctl |= NGBE_SECRXCTL_CRCSTRIP;
                wr32(hw, NGBE_SECRXCTL, rdrxctl);
        }

        ngbe_set_rx_function(dev);

        return 0;
}

/*
 * Initializes Transmit Unit.
 */
void
ngbe_dev_tx_init(struct rte_eth_dev *dev)
{
        struct ngbe_hw     *hw;
        struct ngbe_tx_queue *txq;
        uint64_t bus_addr;
        uint16_t i;

        PMD_INIT_FUNC_TRACE();
        hw = ngbe_dev_hw(dev);

        wr32m(hw, NGBE_SECTXCTL, NGBE_SECTXCTL_ODSA, NGBE_SECTXCTL_ODSA);
        wr32m(hw, NGBE_SECTXCTL, NGBE_SECTXCTL_XDSA, 0);

        /* Setup the Base and Length of the Tx Descriptor Rings */
        for (i = 0; i < dev->data->nb_tx_queues; i++) {
                txq = dev->data->tx_queues[i];

                bus_addr = txq->tx_ring_phys_addr;
                wr32(hw, NGBE_TXBAL(txq->reg_idx),
                                (uint32_t)(bus_addr & BIT_MASK32));
                wr32(hw, NGBE_TXBAH(txq->reg_idx),
                                (uint32_t)(bus_addr >> 32));
                wr32m(hw, NGBE_TXCFG(txq->reg_idx), NGBE_TXCFG_BUFLEN_MASK,
                        NGBE_TXCFG_BUFLEN(txq->nb_tx_desc));
                /* Setup the HW Tx Head and TX Tail descriptor pointers */
                wr32(hw, NGBE_TXRP(txq->reg_idx), 0);
                wr32(hw, NGBE_TXWP(txq->reg_idx), 0);
        }
}

/*
 * Start Transmit and Receive Units.
 */
int
ngbe_dev_rxtx_start(struct rte_eth_dev *dev)
{
        struct ngbe_hw     *hw;
        struct ngbe_tx_queue *txq;
        struct ngbe_rx_queue *rxq;
        uint32_t dmatxctl;
        uint32_t rxctrl;
        uint16_t i;
        int ret = 0;

        PMD_INIT_FUNC_TRACE();
        hw = ngbe_dev_hw(dev);

        for (i = 0; i < dev->data->nb_tx_queues; i++) {
                txq = dev->data->tx_queues[i];
                /* Setup Transmit Threshold Registers */
                wr32m(hw, NGBE_TXCFG(txq->reg_idx),
                      NGBE_TXCFG_HTHRESH_MASK |
                      NGBE_TXCFG_WTHRESH_MASK,
                      NGBE_TXCFG_HTHRESH(txq->hthresh) |
                      NGBE_TXCFG_WTHRESH(txq->wthresh));
        }

        dmatxctl = rd32(hw, NGBE_DMATXCTRL);
        dmatxctl |= NGBE_DMATXCTRL_ENA;
        wr32(hw, NGBE_DMATXCTRL, dmatxctl);

        for (i = 0; i < dev->data->nb_tx_queues; i++) {
                txq = dev->data->tx_queues[i];
                if (txq->tx_deferred_start == 0) {
                        ret = ngbe_dev_tx_queue_start(dev, i);
                        if (ret < 0)
                                return ret;
                }
        }

        for (i = 0; i < dev->data->nb_rx_queues; i++) {
                rxq = dev->data->rx_queues[i];
                if (rxq->rx_deferred_start == 0) {
                        ret = ngbe_dev_rx_queue_start(dev, i);
                        if (ret < 0)
                                return ret;
                }
        }

        /* Enable Receive engine */
        rxctrl = rd32(hw, NGBE_PBRXCTL);
        rxctrl |= NGBE_PBRXCTL_ENA;
        hw->mac.enable_rx_dma(hw, rxctrl);

        return 0;
}

void
ngbe_dev_save_rx_queue(struct ngbe_hw *hw, uint16_t rx_queue_id)
{
        u32 *reg = &hw->q_rx_regs[rx_queue_id * 8];
        *(reg++) = rd32(hw, NGBE_RXBAL(rx_queue_id));
        *(reg++) = rd32(hw, NGBE_RXBAH(rx_queue_id));
        *(reg++) = rd32(hw, NGBE_RXCFG(rx_queue_id));
}

void
ngbe_dev_store_rx_queue(struct ngbe_hw *hw, uint16_t rx_queue_id)
{
        u32 *reg = &hw->q_rx_regs[rx_queue_id * 8];
        wr32(hw, NGBE_RXBAL(rx_queue_id), *(reg++));
        wr32(hw, NGBE_RXBAH(rx_queue_id), *(reg++));
        wr32(hw, NGBE_RXCFG(rx_queue_id), *(reg++) & ~NGBE_RXCFG_ENA);
}

void
ngbe_dev_save_tx_queue(struct ngbe_hw *hw, uint16_t tx_queue_id)
{
        u32 *reg = &hw->q_tx_regs[tx_queue_id * 8];
        *(reg++) = rd32(hw, NGBE_TXBAL(tx_queue_id));
        *(reg++) = rd32(hw, NGBE_TXBAH(tx_queue_id));
        *(reg++) = rd32(hw, NGBE_TXCFG(tx_queue_id));
}

void
ngbe_dev_store_tx_queue(struct ngbe_hw *hw, uint16_t tx_queue_id)
{
        u32 *reg = &hw->q_tx_regs[tx_queue_id * 8];
        wr32(hw, NGBE_TXBAL(tx_queue_id), *(reg++));
        wr32(hw, NGBE_TXBAH(tx_queue_id), *(reg++));
        wr32(hw, NGBE_TXCFG(tx_queue_id), *(reg++) & ~NGBE_TXCFG_ENA);
}

/*
 * Start Receive Units for specified queue.
 */
int
ngbe_dev_rx_queue_start(struct rte_eth_dev *dev, uint16_t rx_queue_id)
{
        struct ngbe_hw *hw = ngbe_dev_hw(dev);
        struct ngbe_rx_queue *rxq;
        uint32_t rxdctl;
        int poll_ms;

        PMD_INIT_FUNC_TRACE();

        rxq = dev->data->rx_queues[rx_queue_id];

        /* Allocate buffers for descriptor rings */
        if (ngbe_alloc_rx_queue_mbufs(rxq) != 0) {
                PMD_INIT_LOG(ERR, "Could not alloc mbuf for queue:%d",
                             rx_queue_id);
                return -1;
        }
        rxdctl = rd32(hw, NGBE_RXCFG(rxq->reg_idx));
        rxdctl |= NGBE_RXCFG_ENA;
        wr32(hw, NGBE_RXCFG(rxq->reg_idx), rxdctl);

        /* Wait until Rx Enable ready */
        poll_ms = RTE_NGBE_REGISTER_POLL_WAIT_10_MS;
        do {
                rte_delay_ms(1);
                rxdctl = rd32(hw, NGBE_RXCFG(rxq->reg_idx));
        } while (--poll_ms && !(rxdctl & NGBE_RXCFG_ENA));
        if (poll_ms == 0)
                PMD_INIT_LOG(ERR, "Could not enable Rx Queue %d", rx_queue_id);
        rte_wmb();
        wr32(hw, NGBE_RXRP(rxq->reg_idx), 0);
        wr32(hw, NGBE_RXWP(rxq->reg_idx), rxq->nb_rx_desc - 1);
        dev->data->rx_queue_state[rx_queue_id] = RTE_ETH_QUEUE_STATE_STARTED;

        return 0;
}

/*
 * Stop Receive Units for specified queue.
 */
int
ngbe_dev_rx_queue_stop(struct rte_eth_dev *dev, uint16_t rx_queue_id)
{
        struct ngbe_hw *hw = ngbe_dev_hw(dev);
        struct ngbe_adapter *adapter = ngbe_dev_adapter(dev);
        struct ngbe_rx_queue *rxq;
        uint32_t rxdctl;
        int poll_ms;

        PMD_INIT_FUNC_TRACE();

        rxq = dev->data->rx_queues[rx_queue_id];

        ngbe_dev_save_rx_queue(hw, rxq->reg_idx);
        wr32m(hw, NGBE_RXCFG(rxq->reg_idx), NGBE_RXCFG_ENA, 0);

        /* Wait until Rx Enable bit clear */
        poll_ms = RTE_NGBE_REGISTER_POLL_WAIT_10_MS;
        do {
                rte_delay_ms(1);
                rxdctl = rd32(hw, NGBE_RXCFG(rxq->reg_idx));
        } while (--poll_ms && (rxdctl & NGBE_RXCFG_ENA));
        if (poll_ms == 0)
                PMD_INIT_LOG(ERR, "Could not disable Rx Queue %d", rx_queue_id);

        rte_delay_us(RTE_NGBE_WAIT_100_US);
        ngbe_dev_store_rx_queue(hw, rxq->reg_idx);

        ngbe_rx_queue_release_mbufs(rxq);
        ngbe_reset_rx_queue(adapter, rxq);
        dev->data->rx_queue_state[rx_queue_id] = RTE_ETH_QUEUE_STATE_STOPPED;

        return 0;
}

/*
 * Start Transmit Units for specified queue.
 */
int
ngbe_dev_tx_queue_start(struct rte_eth_dev *dev, uint16_t tx_queue_id)
{
        struct ngbe_hw *hw = ngbe_dev_hw(dev);
        struct ngbe_tx_queue *txq;
        uint32_t txdctl;
        int poll_ms;

        PMD_INIT_FUNC_TRACE();

        txq = dev->data->tx_queues[tx_queue_id];
        wr32m(hw, NGBE_TXCFG(txq->reg_idx), NGBE_TXCFG_ENA, NGBE_TXCFG_ENA);

        /* Wait until Tx Enable ready */
        poll_ms = RTE_NGBE_REGISTER_POLL_WAIT_10_MS;
        do {
                rte_delay_ms(1);
                txdctl = rd32(hw, NGBE_TXCFG(txq->reg_idx));
        } while (--poll_ms && !(txdctl & NGBE_TXCFG_ENA));
        if (poll_ms == 0)
                PMD_INIT_LOG(ERR, "Could not enable Tx Queue %d",
                             tx_queue_id);

        rte_wmb();
        wr32(hw, NGBE_TXWP(txq->reg_idx), txq->tx_tail);
        dev->data->tx_queue_state[tx_queue_id] = RTE_ETH_QUEUE_STATE_STARTED;

        return 0;
}

/*
 * Stop Transmit Units for specified queue.
 */
int
ngbe_dev_tx_queue_stop(struct rte_eth_dev *dev, uint16_t tx_queue_id)
{
        struct ngbe_hw *hw = ngbe_dev_hw(dev);
        struct ngbe_tx_queue *txq;
        uint32_t txdctl;
        uint32_t txtdh, txtdt;
        int poll_ms;

        PMD_INIT_FUNC_TRACE();

        txq = dev->data->tx_queues[tx_queue_id];

        /* Wait until Tx queue is empty */
        poll_ms = RTE_NGBE_REGISTER_POLL_WAIT_10_MS;
        do {
                rte_delay_us(RTE_NGBE_WAIT_100_US);
                txtdh = rd32(hw, NGBE_TXRP(txq->reg_idx));
                txtdt = rd32(hw, NGBE_TXWP(txq->reg_idx));
        } while (--poll_ms && (txtdh != txtdt));
        if (poll_ms == 0)
                PMD_INIT_LOG(ERR, "Tx Queue %d is not empty when stopping.",
                             tx_queue_id);

        ngbe_dev_save_tx_queue(hw, txq->reg_idx);
        wr32m(hw, NGBE_TXCFG(txq->reg_idx), NGBE_TXCFG_ENA, 0);

        /* Wait until Tx Enable bit clear */
        poll_ms = RTE_NGBE_REGISTER_POLL_WAIT_10_MS;
        do {
                rte_delay_ms(1);
                txdctl = rd32(hw, NGBE_TXCFG(txq->reg_idx));
        } while (--poll_ms && (txdctl & NGBE_TXCFG_ENA));
        if (poll_ms == 0)
                PMD_INIT_LOG(ERR, "Could not disable Tx Queue %d",
                             tx_queue_id);

        rte_delay_us(RTE_NGBE_WAIT_100_US);
        ngbe_dev_store_tx_queue(hw, txq->reg_idx);

        if (txq->ops != NULL) {
                txq->ops->release_mbufs(txq);
                txq->ops->reset(txq);
        }
        dev->data->tx_queue_state[tx_queue_id] = RTE_ETH_QUEUE_STATE_STOPPED;

        return 0;
}