New upstream version 17.11.5

[deb_dpdk.git] / drivers / net / e1000 / igb_rxtx.c

/*-
 *   BSD LICENSE
 *
 *   Copyright(c) 2010-2016 Intel Corporation. All rights reserved.
 *   All rights reserved.
 *
 *   Redistribution and use in source and binary forms, with or without
 *   modification, are permitted provided that the following conditions
 *   are met:
 *
 *     * Redistributions of source code must retain the above copyright
 *       notice, this list of conditions and the following disclaimer.
 *     * Redistributions in binary form must reproduce the above copyright
 *       notice, this list of conditions and the following disclaimer in
 *       the documentation and/or other materials provided with the
 *       distribution.
 *     * Neither the name of Intel Corporation nor the names of its
 *       contributors may be used to endorse or promote products derived
 *       from this software without specific prior written permission.
 *
 *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include <sys/queue.h>

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <stdint.h>
#include <stdarg.h>
#include <inttypes.h>

#include <rte_interrupts.h>
#include <rte_byteorder.h>
#include <rte_common.h>
#include <rte_log.h>
#include <rte_debug.h>
#include <rte_pci.h>
#include <rte_memory.h>
#include <rte_memcpy.h>
#include <rte_memzone.h>
#include <rte_launch.h>
#include <rte_eal.h>
#include <rte_per_lcore.h>
#include <rte_lcore.h>
#include <rte_atomic.h>
#include <rte_branch_prediction.h>
#include <rte_mempool.h>
#include <rte_malloc.h>
#include <rte_mbuf.h>
#include <rte_ether.h>
#include <rte_ethdev.h>
#include <rte_prefetch.h>
#include <rte_udp.h>
#include <rte_tcp.h>
#include <rte_sctp.h>
#include <rte_net.h>
#include <rte_string_fns.h>

#include "e1000_logs.h"
#include "base/e1000_api.h"
#include "e1000_ethdev.h"

#ifdef RTE_LIBRTE_IEEE1588
#define IGB_TX_IEEE1588_TMST PKT_TX_IEEE1588_TMST
#else
#define IGB_TX_IEEE1588_TMST 0
#endif
/* Bit Mask to indicate what bits required for building TX context */
#define IGB_TX_OFFLOAD_MASK (                    \
                PKT_TX_OUTER_IPV6 |      \
                PKT_TX_OUTER_IPV4 |      \
                PKT_TX_IPV6 |            \
                PKT_TX_IPV4 |            \
                PKT_TX_VLAN_PKT |                \
                PKT_TX_IP_CKSUM |                \
                PKT_TX_L4_MASK |                 \
                PKT_TX_TCP_SEG |                 \
                IGB_TX_IEEE1588_TMST)

#define IGB_TX_OFFLOAD_NOTSUP_MASK \
                (PKT_TX_OFFLOAD_MASK ^ IGB_TX_OFFLOAD_MASK)

/**
 * Structure associated with each descriptor of the RX ring of a RX queue.
 */
struct igb_rx_entry {
        struct rte_mbuf *mbuf; /**< mbuf associated with RX descriptor. */
};

/**
 * Structure associated with each descriptor of the TX ring of a TX queue.
 */
struct igb_tx_entry {
        struct rte_mbuf *mbuf; /**< mbuf associated with TX desc, if any. */
        uint16_t next_id; /**< Index of next descriptor in ring. */
        uint16_t last_id; /**< Index of last scattered descriptor. */
};

/**
 * rx queue flags
 */
enum igb_rxq_flags {
        IGB_RXQ_FLAG_LB_BSWAP_VLAN = 0x01,
};

/**
 * Structure associated with each RX queue.
 */
struct igb_rx_queue {
        struct rte_mempool  *mb_pool;   /**< mbuf pool to populate RX ring. */
        volatile union e1000_adv_rx_desc *rx_ring; /**< RX ring virtual address. */
        uint64_t            rx_ring_phys_addr; /**< RX ring DMA address. */
        volatile uint32_t   *rdt_reg_addr; /**< RDT register address. */
        volatile uint32_t   *rdh_reg_addr; /**< RDH register address. */
        struct igb_rx_entry *sw_ring;   /**< address of RX software ring. */
        struct rte_mbuf *pkt_first_seg; /**< First segment of current packet. */
        struct rte_mbuf *pkt_last_seg;  /**< Last segment of current packet. */
        uint16_t            nb_rx_desc; /**< number of RX descriptors. */
        uint16_t            rx_tail;    /**< current value of RDT register. */
        uint16_t            nb_rx_hold; /**< number of held free RX desc. */
        uint16_t            rx_free_thresh; /**< max free RX desc to hold. */
        uint16_t            queue_id;   /**< RX queue index. */
        uint16_t            reg_idx;    /**< RX queue register index. */
        uint16_t            port_id;    /**< Device port identifier. */
        uint8_t             pthresh;    /**< Prefetch threshold register. */
        uint8_t             hthresh;    /**< Host threshold register. */
        uint8_t             wthresh;    /**< Write-back threshold register. */
        uint8_t             crc_len;    /**< 0 if CRC stripped, 4 otherwise. */
        uint8_t             drop_en;  /**< If not 0, set SRRCTL.Drop_En. */
        uint32_t            flags;      /**< RX flags. */
};

/**
 * Hardware context number
 */
enum igb_advctx_num {
        IGB_CTX_0    = 0, /**< CTX0    */
        IGB_CTX_1    = 1, /**< CTX1    */
        IGB_CTX_NUM  = 2, /**< CTX_NUM */
};

/** Offload features */
union igb_tx_offload {
        uint64_t data;
        struct {
                uint64_t l3_len:9; /**< L3 (IP) Header Length. */
                uint64_t l2_len:7; /**< L2 (MAC) Header Length. */
                uint64_t vlan_tci:16;  /**< VLAN Tag Control Identifier(CPU order). */
                uint64_t l4_len:8; /**< L4 (TCP/UDP) Header Length. */
                uint64_t tso_segsz:16; /**< TCP TSO segment size. */

                /* uint64_t unused:8; */
        };
};

/*
 * Compare mask for igb_tx_offload.data,
 * should be in sync with igb_tx_offload layout.
 * */
#define TX_MACIP_LEN_CMP_MASK   0x000000000000FFFFULL /**< L2L3 header mask. */
#define TX_VLAN_CMP_MASK                0x00000000FFFF0000ULL /**< Vlan mask. */
#define TX_TCP_LEN_CMP_MASK             0x000000FF00000000ULL /**< TCP header mask. */
#define TX_TSO_MSS_CMP_MASK             0x00FFFF0000000000ULL /**< TSO segsz mask. */
/** Mac + IP + TCP + Mss mask. */
#define TX_TSO_CMP_MASK \
        (TX_MACIP_LEN_CMP_MASK | TX_TCP_LEN_CMP_MASK | TX_TSO_MSS_CMP_MASK)

/**
 * Strucutre to check if new context need be built
 */
struct igb_advctx_info {
        uint64_t flags;           /**< ol_flags related to context build. */
        /** tx offload: vlan, tso, l2-l3-l4 lengths. */
        union igb_tx_offload tx_offload;
        /** compare mask for tx offload. */
        union igb_tx_offload tx_offload_mask;
};

/**
 * Structure associated with each TX queue.
 */
struct igb_tx_queue {
        volatile union e1000_adv_tx_desc *tx_ring; /**< TX ring address */
        uint64_t               tx_ring_phys_addr; /**< TX ring DMA address. */
        struct igb_tx_entry    *sw_ring; /**< virtual address of SW ring. */
        volatile uint32_t      *tdt_reg_addr; /**< Address of TDT register. */
        uint32_t               txd_type;      /**< Device-specific TXD type */
        uint16_t               nb_tx_desc;    /**< number of TX descriptors. */
        uint16_t               tx_tail; /**< Current value of TDT register. */
        uint16_t               tx_head;
        /**< Index of first used TX descriptor. */
        uint16_t               queue_id; /**< TX queue index. */
        uint16_t               reg_idx;  /**< TX queue register index. */
        uint16_t               port_id;  /**< Device port identifier. */
        uint8_t                pthresh;  /**< Prefetch threshold register. */
        uint8_t                hthresh;  /**< Host threshold register. */
        uint8_t                wthresh;  /**< Write-back threshold register. */
        uint32_t               ctx_curr;
        /**< Current used hardware descriptor. */
        uint32_t               ctx_start;
        /**< Start context position for transmit queue. */
        struct igb_advctx_info ctx_cache[IGB_CTX_NUM];
        /**< Hardware context history.*/
};

#if 1
#define RTE_PMD_USE_PREFETCH
#endif

#ifdef RTE_PMD_USE_PREFETCH
#define rte_igb_prefetch(p)     rte_prefetch0(p)
#else
#define rte_igb_prefetch(p)     do {} while(0)
#endif

#ifdef RTE_PMD_PACKET_PREFETCH
#define rte_packet_prefetch(p) rte_prefetch1(p)
#else
#define rte_packet_prefetch(p)  do {} while(0)
#endif

/*
 * Macro for VMDq feature for 1 GbE NIC.
 */
#define E1000_VMOLR_SIZE                        (8)
#define IGB_TSO_MAX_HDRLEN                      (512)
#define IGB_TSO_MAX_MSS                         (9216)

/*********************************************************************
 *
 *  TX function
 *
 **********************************************************************/

/*
 *There're some limitations in hardware for TCP segmentation offload. We
 *should check whether the parameters are valid.
 */
static inline uint64_t
check_tso_para(uint64_t ol_req, union igb_tx_offload ol_para)
{
        if (!(ol_req & PKT_TX_TCP_SEG))
                return ol_req;
        if ((ol_para.tso_segsz > IGB_TSO_MAX_MSS) || (ol_para.l2_len +
                        ol_para.l3_len + ol_para.l4_len > IGB_TSO_MAX_HDRLEN)) {
                ol_req &= ~PKT_TX_TCP_SEG;
                ol_req |= PKT_TX_TCP_CKSUM;
        }
        return ol_req;
}

/*
 * Advanced context descriptor are almost same between igb/ixgbe
 * This is a separate function, looking for optimization opportunity here
 * Rework required to go with the pre-defined values.
 */

static inline void
igbe_set_xmit_ctx(struct igb_tx_queue* txq,
                volatile struct e1000_adv_tx_context_desc *ctx_txd,
                uint64_t ol_flags, union igb_tx_offload tx_offload)
{
        uint32_t type_tucmd_mlhl;
        uint32_t mss_l4len_idx;
        uint32_t ctx_idx, ctx_curr;
        uint32_t vlan_macip_lens;
        union igb_tx_offload tx_offload_mask;

        ctx_curr = txq->ctx_curr;
        ctx_idx = ctx_curr + txq->ctx_start;

        tx_offload_mask.data = 0;
        type_tucmd_mlhl = 0;

        /* Specify which HW CTX to upload. */
        mss_l4len_idx = (ctx_idx << E1000_ADVTXD_IDX_SHIFT);

        if (ol_flags & PKT_TX_VLAN_PKT)
                tx_offload_mask.data |= TX_VLAN_CMP_MASK;

        /* check if TCP segmentation required for this packet */
        if (ol_flags & PKT_TX_TCP_SEG) {
                /* implies IP cksum in IPv4 */
                if (ol_flags & PKT_TX_IP_CKSUM)
                        type_tucmd_mlhl = E1000_ADVTXD_TUCMD_IPV4 |
                                E1000_ADVTXD_TUCMD_L4T_TCP |
                                E1000_ADVTXD_DTYP_CTXT | E1000_ADVTXD_DCMD_DEXT;
                else
                        type_tucmd_mlhl = E1000_ADVTXD_TUCMD_IPV6 |
                                E1000_ADVTXD_TUCMD_L4T_TCP |
                                E1000_ADVTXD_DTYP_CTXT | E1000_ADVTXD_DCMD_DEXT;

                tx_offload_mask.data |= TX_TSO_CMP_MASK;
                mss_l4len_idx |= tx_offload.tso_segsz << E1000_ADVTXD_MSS_SHIFT;
                mss_l4len_idx |= tx_offload.l4_len << E1000_ADVTXD_L4LEN_SHIFT;
        } else { /* no TSO, check if hardware checksum is needed */
                if (ol_flags & (PKT_TX_IP_CKSUM | PKT_TX_L4_MASK))
                        tx_offload_mask.data |= TX_MACIP_LEN_CMP_MASK;

                if (ol_flags & PKT_TX_IP_CKSUM)
                        type_tucmd_mlhl = E1000_ADVTXD_TUCMD_IPV4;

                switch (ol_flags & PKT_TX_L4_MASK) {
                case PKT_TX_UDP_CKSUM:
                        type_tucmd_mlhl |= E1000_ADVTXD_TUCMD_L4T_UDP |
                                E1000_ADVTXD_DTYP_CTXT | E1000_ADVTXD_DCMD_DEXT;
                        mss_l4len_idx |= sizeof(struct udp_hdr) << E1000_ADVTXD_L4LEN_SHIFT;
                        break;
                case PKT_TX_TCP_CKSUM:
                        type_tucmd_mlhl |= E1000_ADVTXD_TUCMD_L4T_TCP |
                                E1000_ADVTXD_DTYP_CTXT | E1000_ADVTXD_DCMD_DEXT;
                        mss_l4len_idx |= sizeof(struct tcp_hdr) << E1000_ADVTXD_L4LEN_SHIFT;
                        break;
                case PKT_TX_SCTP_CKSUM:
                        type_tucmd_mlhl |= E1000_ADVTXD_TUCMD_L4T_SCTP |
                                E1000_ADVTXD_DTYP_CTXT | E1000_ADVTXD_DCMD_DEXT;
                        mss_l4len_idx |= sizeof(struct sctp_hdr) << E1000_ADVTXD_L4LEN_SHIFT;
                        break;
                default:
                        type_tucmd_mlhl |= E1000_ADVTXD_TUCMD_L4T_RSV |
                                E1000_ADVTXD_DTYP_CTXT | E1000_ADVTXD_DCMD_DEXT;
                        break;
                }
        }

        txq->ctx_cache[ctx_curr].flags = ol_flags;
        txq->ctx_cache[ctx_curr].tx_offload.data =
                tx_offload_mask.data & tx_offload.data;
        txq->ctx_cache[ctx_curr].tx_offload_mask = tx_offload_mask;

        ctx_txd->type_tucmd_mlhl = rte_cpu_to_le_32(type_tucmd_mlhl);
        vlan_macip_lens = (uint32_t)tx_offload.data;
        ctx_txd->vlan_macip_lens = rte_cpu_to_le_32(vlan_macip_lens);
        ctx_txd->mss_l4len_idx = rte_cpu_to_le_32(mss_l4len_idx);
        ctx_txd->seqnum_seed = 0;
}

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

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

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

static inline uint32_t
tx_desc_cksum_flags_to_olinfo(uint64_t ol_flags)
{
        static const uint32_t l4_olinfo[2] = {0, E1000_ADVTXD_POPTS_TXSM};
        static const uint32_t l3_olinfo[2] = {0, E1000_ADVTXD_POPTS_IXSM};
        uint32_t tmp;

        tmp  = l4_olinfo[(ol_flags & PKT_TX_L4_MASK)  != PKT_TX_L4_NO_CKSUM];
        tmp |= l3_olinfo[(ol_flags & PKT_TX_IP_CKSUM) != 0];
        tmp |= l4_olinfo[(ol_flags & PKT_TX_TCP_SEG) != 0];
        return tmp;
}

static inline uint32_t
tx_desc_vlan_flags_to_cmdtype(uint64_t ol_flags)
{
        uint32_t cmdtype;
        static uint32_t vlan_cmd[2] = {0, E1000_ADVTXD_DCMD_VLE};
        static uint32_t tso_cmd[2] = {0, E1000_ADVTXD_DCMD_TSE};
        cmdtype = vlan_cmd[(ol_flags & PKT_TX_VLAN_PKT) != 0];
        cmdtype |= tso_cmd[(ol_flags & PKT_TX_TCP_SEG) != 0];
        return cmdtype;
}

uint16_t
eth_igb_xmit_pkts(void *tx_queue, struct rte_mbuf **tx_pkts,
               uint16_t nb_pkts)
{
        struct igb_tx_queue *txq;
        struct igb_tx_entry *sw_ring;
        struct igb_tx_entry *txe, *txn;
        volatile union e1000_adv_tx_desc *txr;
        volatile union e1000_adv_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_end;
        uint16_t tx_id;
        uint16_t tx_last;
        uint16_t nb_tx;
        uint64_t tx_ol_req;
        uint32_t new_ctx = 0;
        uint32_t ctx = 0;
        union igb_tx_offload tx_offload = {0};

        txq = tx_queue;
        sw_ring = txq->sw_ring;
        txr     = txq->tx_ring;
        tx_id   = txq->tx_tail;
        txe = &sw_ring[tx_id];

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

                RTE_MBUF_PREFETCH_TO_FREE(txe->mbuf);

                /*
                 * 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 VLAN Tag Identifier, 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 + tx_pkt->nb_segs - 1);

                ol_flags = tx_pkt->ol_flags;
                tx_ol_req = ol_flags & IGB_TX_OFFLOAD_MASK;

                /* If a Context Descriptor need be built . */
                if (tx_ol_req) {
                        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.vlan_tci = tx_pkt->vlan_tci;
                        tx_offload.tso_segsz = tx_pkt->tso_segsz;
                        tx_ol_req = check_tso_para(tx_ol_req, tx_offload);

                        ctx = what_advctx_update(txq, tx_ol_req, tx_offload);
                        /* Only allocate context descriptor if required*/
                        new_ctx = (ctx == IGB_CTX_NUM);
                        ctx = txq->ctx_curr + txq->ctx_start;
                        tx_last = (uint16_t) (tx_last + new_ctx);
                }
                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",
                           (unsigned) txq->port_id,
                           (unsigned) txq->queue_id,
                           (unsigned) pkt_len,
                           (unsigned) tx_id,
                           (unsigned) tx_last);

                /*
                 * Check if there are enough free descriptors in the TX ring
                 * to transmit the next packet.
                 * This operation is based on the two following rules:
                 *
                 *   1- Only check that the last needed TX descriptor can be
                 *      allocated (by construction, if that descriptor is free,
                 *      all intermediate ones are also free).
                 *
                 *      For this purpose, the index of the last TX descriptor
                 *      used for a packet (the "last descriptor" of a packet)
                 *      is recorded in the TX entries (the last one included)
                 *      that are associated with all TX descriptors allocated
                 *      for that packet.
                 *
                 *   2- Avoid to allocate the last free TX descriptor of the
                 *      ring, in order to never set the TDT register with the
                 *      same value stored in parallel by the NIC in the TDH
                 *      register, which makes the TX engine of the NIC enter
                 *      in a deadlock situation.
                 *
                 *      By extension, avoid to allocate a free descriptor that
                 *      belongs to the last set of free descriptors allocated
                 *      to the same packet previously transmitted.
                 */

                /*
                 * The "last descriptor" of the previously sent packet, if any,
                 * which used the last descriptor to allocate.
                 */
                tx_end = sw_ring[tx_last].last_id;

                /*
                 * The next descriptor following that "last descriptor" in the
                 * ring.
                 */
                tx_end = sw_ring[tx_end].next_id;

                /*
                 * The "last descriptor" associated with that next descriptor.
                 */
                tx_end = sw_ring[tx_end].last_id;

                /*
                 * Check that this descriptor is free.
                 */
                if (! (txr[tx_end].wb.status & E1000_TXD_STAT_DD)) {
                        if (nb_tx == 0)
                                return 0;
                        goto end_of_tx;
                }

                /*
                 * Set common flags of all TX Data Descriptors.
                 *
                 * The following bits must be set in all Data Descriptors:
                 *   - E1000_ADVTXD_DTYP_DATA
                 *   - E1000_ADVTXD_DCMD_DEXT
                 *
                 * The following bits must be set in the first Data Descriptor
                 * and are ignored in the other ones:
                 *   - E1000_ADVTXD_DCMD_IFCS
                 *   - E1000_ADVTXD_MAC_1588
                 *   - E1000_ADVTXD_DCMD_VLE
                 *
                 * The following bits must only be set in the last Data
                 * Descriptor:
                 *   - E1000_TXD_CMD_EOP
                 *
                 * The following bits can be set in any Data Descriptor, but
                 * are only set in the last Data Descriptor:
                 *   - E1000_TXD_CMD_RS
                 */
                cmd_type_len = txq->txd_type |
                        E1000_ADVTXD_DCMD_IFCS | E1000_ADVTXD_DCMD_DEXT;
                if (tx_ol_req & PKT_TX_TCP_SEG)
                        pkt_len -= (tx_pkt->l2_len + tx_pkt->l3_len + tx_pkt->l4_len);
                olinfo_status = (pkt_len << E1000_ADVTXD_PAYLEN_SHIFT);
#if defined(RTE_LIBRTE_IEEE1588)
                if (ol_flags & PKT_TX_IEEE1588_TMST)
                        cmd_type_len |= E1000_ADVTXD_MAC_TSTAMP;
#endif
                if (tx_ol_req) {
                        /* Setup TX Advanced context descriptor if required */
                        if (new_ctx) {
                                volatile struct e1000_adv_tx_context_desc *
                                    ctx_txd;

                                ctx_txd = (volatile struct
                                    e1000_adv_tx_context_desc *)
                                    &txr[tx_id];

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

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

                                igbe_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 Advanced Data Descriptor */
                        cmd_type_len  |= tx_desc_vlan_flags_to_cmdtype(tx_ol_req);
                        olinfo_status |= tx_desc_cksum_flags_to_olinfo(tx_ol_req);
                        olinfo_status |= (ctx << E1000_ADVTXD_IDX_SHIFT);
                }

                m_seg = tx_pkt;
                do {
                        txn = &sw_ring[txe->next_id];
                        txd = &txr[tx_id];

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

                        /*
                         * Set up transmit descriptor.
                         */
                        slen = (uint16_t) m_seg->data_len;
                        buf_dma_addr = rte_mbuf_data_iova(m_seg);
                        txd->read.buffer_addr =
                                rte_cpu_to_le_64(buf_dma_addr);
                        txd->read.cmd_type_len =
                                rte_cpu_to_le_32(cmd_type_len | slen);
                        txd->read.olinfo_status =
                                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)
                 * and Report Status (RS).
                 */
                txd->read.cmd_type_len |=
                        rte_cpu_to_le_32(E1000_TXD_CMD_EOP | E1000_TXD_CMD_RS);
        }
 end_of_tx:
        rte_wmb();

        /*
         * Set the Transmit Descriptor Tail (TDT).
         */
        E1000_PCI_REG_WRITE_RELAXED(txq->tdt_reg_addr, tx_id);
        PMD_TX_LOG(DEBUG, "port_id=%u queue_id=%u tx_tail=%u nb_tx=%u",
                   (unsigned) txq->port_id, (unsigned) txq->queue_id,
                   (unsigned) tx_id, (unsigned) nb_tx);
        txq->tx_tail = tx_id;

        return nb_tx;
}

/*********************************************************************
 *
 *  TX prep functions
 *
 **********************************************************************/
uint16_t
eth_igb_prep_pkts(__rte_unused void *tx_queue, struct rte_mbuf **tx_pkts,
                uint16_t nb_pkts)
{
        int i, ret;
        struct rte_mbuf *m;

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

                /* Check some limitations for TSO in hardware */
                if (m->ol_flags & PKT_TX_TCP_SEG)
                        if ((m->tso_segsz > IGB_TSO_MAX_MSS) ||
                                        (m->l2_len + m->l3_len + m->l4_len >
                                        IGB_TSO_MAX_HDRLEN)) {
                                rte_errno = -EINVAL;
                                return i;
                        }

                if (m->ol_flags & IGB_TX_OFFLOAD_NOTSUP_MASK) {
                        rte_errno = -ENOTSUP;
                        return i;
                }

#ifdef RTE_LIBRTE_ETHDEV_DEBUG
                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
 *
 **********************************************************************/
#define IGB_PACKET_TYPE_IPV4              0X01
#define IGB_PACKET_TYPE_IPV4_TCP          0X11
#define IGB_PACKET_TYPE_IPV4_UDP          0X21
#define IGB_PACKET_TYPE_IPV4_SCTP         0X41
#define IGB_PACKET_TYPE_IPV4_EXT          0X03
#define IGB_PACKET_TYPE_IPV4_EXT_SCTP     0X43
#define IGB_PACKET_TYPE_IPV6              0X04
#define IGB_PACKET_TYPE_IPV6_TCP          0X14
#define IGB_PACKET_TYPE_IPV6_UDP          0X24
#define IGB_PACKET_TYPE_IPV6_EXT          0X0C
#define IGB_PACKET_TYPE_IPV6_EXT_TCP      0X1C
#define IGB_PACKET_TYPE_IPV6_EXT_UDP      0X2C
#define IGB_PACKET_TYPE_IPV4_IPV6         0X05
#define IGB_PACKET_TYPE_IPV4_IPV6_TCP     0X15
#define IGB_PACKET_TYPE_IPV4_IPV6_UDP     0X25
#define IGB_PACKET_TYPE_IPV4_IPV6_EXT     0X0D
#define IGB_PACKET_TYPE_IPV4_IPV6_EXT_TCP 0X1D
#define IGB_PACKET_TYPE_IPV4_IPV6_EXT_UDP 0X2D
#define IGB_PACKET_TYPE_MAX               0X80
#define IGB_PACKET_TYPE_MASK              0X7F
#define IGB_PACKET_TYPE_SHIFT             0X04
static inline uint32_t
igb_rxd_pkt_info_to_pkt_type(uint16_t pkt_info)
{
        static const uint32_t
                ptype_table[IGB_PACKET_TYPE_MAX] __rte_cache_aligned = {
                [IGB_PACKET_TYPE_IPV4] = RTE_PTYPE_L2_ETHER |
                        RTE_PTYPE_L3_IPV4,
                [IGB_PACKET_TYPE_IPV4_EXT] = RTE_PTYPE_L2_ETHER |
                        RTE_PTYPE_L3_IPV4_EXT,
                [IGB_PACKET_TYPE_IPV6] = RTE_PTYPE_L2_ETHER |
                        RTE_PTYPE_L3_IPV6,
                [IGB_PACKET_TYPE_IPV4_IPV6] = RTE_PTYPE_L2_ETHER |
                        RTE_PTYPE_L3_IPV4 | RTE_PTYPE_TUNNEL_IP |
                        RTE_PTYPE_INNER_L3_IPV6,
                [IGB_PACKET_TYPE_IPV6_EXT] = RTE_PTYPE_L2_ETHER |
                        RTE_PTYPE_L3_IPV6_EXT,
                [IGB_PACKET_TYPE_IPV4_IPV6_EXT] = RTE_PTYPE_L2_ETHER |
                        RTE_PTYPE_L3_IPV4 | RTE_PTYPE_TUNNEL_IP |
                        RTE_PTYPE_INNER_L3_IPV6_EXT,
                [IGB_PACKET_TYPE_IPV4_TCP] = RTE_PTYPE_L2_ETHER |
                        RTE_PTYPE_L3_IPV4 | RTE_PTYPE_L4_TCP,
                [IGB_PACKET_TYPE_IPV6_TCP] = RTE_PTYPE_L2_ETHER |
                        RTE_PTYPE_L3_IPV6 | RTE_PTYPE_L4_TCP,
                [IGB_PACKET_TYPE_IPV4_IPV6_TCP] = RTE_PTYPE_L2_ETHER |
                        RTE_PTYPE_L3_IPV4 | RTE_PTYPE_TUNNEL_IP |
                        RTE_PTYPE_INNER_L3_IPV6 | RTE_PTYPE_INNER_L4_TCP,
                [IGB_PACKET_TYPE_IPV6_EXT_TCP] = RTE_PTYPE_L2_ETHER |
                        RTE_PTYPE_L3_IPV6_EXT | RTE_PTYPE_L4_TCP,
                [IGB_PACKET_TYPE_IPV4_IPV6_EXT_TCP] = RTE_PTYPE_L2_ETHER |
                        RTE_PTYPE_L3_IPV4 | RTE_PTYPE_TUNNEL_IP |
                        RTE_PTYPE_INNER_L3_IPV6_EXT | RTE_PTYPE_INNER_L4_TCP,
                [IGB_PACKET_TYPE_IPV4_UDP] = RTE_PTYPE_L2_ETHER |
                        RTE_PTYPE_L3_IPV4 | RTE_PTYPE_L4_UDP,
                [IGB_PACKET_TYPE_IPV6_UDP] = RTE_PTYPE_L2_ETHER |
                        RTE_PTYPE_L3_IPV6 | RTE_PTYPE_L4_UDP,
                [IGB_PACKET_TYPE_IPV4_IPV6_UDP] =  RTE_PTYPE_L2_ETHER |
                        RTE_PTYPE_L3_IPV4 | RTE_PTYPE_TUNNEL_IP |
                        RTE_PTYPE_INNER_L3_IPV6 | RTE_PTYPE_INNER_L4_UDP,
                [IGB_PACKET_TYPE_IPV6_EXT_UDP] = RTE_PTYPE_L2_ETHER |
                        RTE_PTYPE_L3_IPV6_EXT | RTE_PTYPE_L4_UDP,
                [IGB_PACKET_TYPE_IPV4_IPV6_EXT_UDP] = RTE_PTYPE_L2_ETHER |
                        RTE_PTYPE_L3_IPV4 | RTE_PTYPE_TUNNEL_IP |
                        RTE_PTYPE_INNER_L3_IPV6_EXT | RTE_PTYPE_INNER_L4_UDP,
                [IGB_PACKET_TYPE_IPV4_SCTP] = RTE_PTYPE_L2_ETHER |
                        RTE_PTYPE_L3_IPV4 | RTE_PTYPE_L4_SCTP,
                [IGB_PACKET_TYPE_IPV4_EXT_SCTP] = RTE_PTYPE_L2_ETHER |
                        RTE_PTYPE_L3_IPV4_EXT | RTE_PTYPE_L4_SCTP,
        };
        if (unlikely(pkt_info & E1000_RXDADV_PKTTYPE_ETQF))
                return RTE_PTYPE_UNKNOWN;

        pkt_info = (pkt_info >> IGB_PACKET_TYPE_SHIFT) & IGB_PACKET_TYPE_MASK;

        return ptype_table[pkt_info];
}

static inline uint64_t
rx_desc_hlen_type_rss_to_pkt_flags(struct igb_rx_queue *rxq, uint32_t hl_tp_rs)
{
        uint64_t pkt_flags = ((hl_tp_rs & 0x0F) == 0) ?  0 : PKT_RX_RSS_HASH;

#if defined(RTE_LIBRTE_IEEE1588)
        static uint32_t ip_pkt_etqf_map[8] = {
                0, 0, 0, PKT_RX_IEEE1588_PTP,
                0, 0, 0, 0,
        };

        struct rte_eth_dev dev = rte_eth_devices[rxq->port_id];
        struct e1000_hw *hw = E1000_DEV_PRIVATE_TO_HW(dev.data->dev_private);

        /* EtherType is in bits 8:10 in Packet Type, and not in the default 0:2 */
        if (hw->mac.type == e1000_i210)
                pkt_flags |= ip_pkt_etqf_map[(hl_tp_rs >> 12) & 0x07];
        else
                pkt_flags |= ip_pkt_etqf_map[(hl_tp_rs >> 4) & 0x07];
#else
        RTE_SET_USED(rxq);
#endif

        return pkt_flags;
}

static inline uint64_t
rx_desc_status_to_pkt_flags(uint32_t rx_status)
{
        uint64_t pkt_flags;

        /* Check if VLAN present */
        pkt_flags = ((rx_status & E1000_RXD_STAT_VP) ?
                PKT_RX_VLAN | PKT_RX_VLAN_STRIPPED : 0);

#if defined(RTE_LIBRTE_IEEE1588)
        if (rx_status & E1000_RXD_STAT_TMST)
                pkt_flags = pkt_flags | PKT_RX_IEEE1588_TMST;
#endif
        return pkt_flags;
}

static inline uint64_t
rx_desc_error_to_pkt_flags(uint32_t rx_status)
{
        /*
         * Bit 30: IPE, IPv4 checksum error
         * Bit 29: L4I, L4I integrity error
         */

        static uint64_t error_to_pkt_flags_map[4] = {
                PKT_RX_IP_CKSUM_GOOD | PKT_RX_L4_CKSUM_GOOD,
                PKT_RX_IP_CKSUM_GOOD | PKT_RX_L4_CKSUM_BAD,
                PKT_RX_IP_CKSUM_BAD | PKT_RX_L4_CKSUM_GOOD,
                PKT_RX_IP_CKSUM_BAD | PKT_RX_L4_CKSUM_BAD
        };
        return error_to_pkt_flags_map[(rx_status >>
                E1000_RXD_ERR_CKSUM_BIT) & E1000_RXD_ERR_CKSUM_MSK];
}

uint16_t
eth_igb_recv_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
               uint16_t nb_pkts)
{
        struct igb_rx_queue *rxq;
        volatile union e1000_adv_rx_desc *rx_ring;
        volatile union e1000_adv_rx_desc *rxdp;
        struct igb_rx_entry *sw_ring;
        struct igb_rx_entry *rxe;
        struct rte_mbuf *rxm;
        struct rte_mbuf *nmb;
        union e1000_adv_rx_desc rxd;
        uint64_t dma_addr;
        uint32_t staterr;
        uint32_t hlen_type_rss;
        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;
        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->wb.upper.status_error;
                if (! (staterr & rte_cpu_to_le_32(E1000_RXD_STAT_DD)))
                        break;
                rxd = *rxdp;

                /*
                 * End of packet.
                 *
                 * If the E1000_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 "
                           "staterr=0x%x pkt_len=%u",
                           (unsigned) rxq->port_id, (unsigned) rxq->queue_id,
                           (unsigned) rx_id, (unsigned) staterr,
                           (unsigned) rte_le_to_cpu_16(rxd.wb.upper.length));

                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", (unsigned) rxq->port_id,
                                   (unsigned) rxq->queue_id);
                        rte_eth_devices[rxq->port_id].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_igb_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_igb_prefetch(&rx_ring[rx_id]);
                        rte_igb_prefetch(&sw_ring[rx_id]);
                }

                rxm = rxe->mbuf;
                rxe->mbuf = nmb;
                dma_addr =
                        rte_cpu_to_le_64(rte_mbuf_data_iova_default(nmb));
                rxdp->read.hdr_addr = 0;
                rxdp->read.pkt_addr = 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:
                 *    - RSS flag & hash,
                 *    - IP checksum flag,
                 *    - VLAN TCI, if any,
                 *    - error flags.
                 */
                pkt_len = (uint16_t) (rte_le_to_cpu_16(rxd.wb.upper.length) -
                                      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;

                rxm->hash.rss = rxd.wb.lower.hi_dword.rss;
                hlen_type_rss = rte_le_to_cpu_32(rxd.wb.lower.lo_dword.data);

                /*
                 * The vlan_tci field is only valid when PKT_RX_VLAN is
                 * set in the pkt_flags field and must be in CPU byte order.
                 */
                if ((staterr & rte_cpu_to_le_32(E1000_RXDEXT_STATERR_LB)) &&
                                (rxq->flags & IGB_RXQ_FLAG_LB_BSWAP_VLAN)) {
                        rxm->vlan_tci = rte_be_to_cpu_16(rxd.wb.upper.vlan);
                } else {
                        rxm->vlan_tci = rte_le_to_cpu_16(rxd.wb.upper.vlan);
                }
                pkt_flags = rx_desc_hlen_type_rss_to_pkt_flags(rxq, hlen_type_rss);
                pkt_flags = pkt_flags | rx_desc_status_to_pkt_flags(staterr);
                pkt_flags = pkt_flags | rx_desc_error_to_pkt_flags(staterr);
                rxm->ol_flags = pkt_flags;
                rxm->packet_type = igb_rxd_pkt_info_to_pkt_type(rxd.wb.lower.
                                                lo_dword.hs_rss.pkt_info);

                /*
                 * 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 situtation 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",
                           (unsigned) rxq->port_id, (unsigned) rxq->queue_id,
                           (unsigned) rx_id, (unsigned) nb_hold,
                           (unsigned) nb_rx);
                rx_id = (uint16_t) ((rx_id == 0) ?
                                     (rxq->nb_rx_desc - 1) : (rx_id - 1));
                E1000_PCI_REG_WRITE(rxq->rdt_reg_addr, rx_id);
                nb_hold = 0;
        }
        rxq->nb_rx_hold = nb_hold;
        return nb_rx;
}

uint16_t
eth_igb_recv_scattered_pkts(void *rx_queue, struct rte_mbuf **rx_pkts,
                         uint16_t nb_pkts)
{
        struct igb_rx_queue *rxq;
        volatile union e1000_adv_rx_desc *rx_ring;
        volatile union e1000_adv_rx_desc *rxdp;
        struct igb_rx_entry *sw_ring;
        struct igb_rx_entry *rxe;
        struct rte_mbuf *first_seg;
        struct rte_mbuf *last_seg;
        struct rte_mbuf *rxm;
        struct rte_mbuf *nmb;
        union e1000_adv_rx_desc rxd;
        uint64_t dma; /* Physical address of mbuf data buffer */
        uint32_t staterr;
        uint32_t hlen_type_rss;
        uint16_t rx_id;
        uint16_t nb_rx;
        uint16_t nb_hold;
        uint16_t data_len;
        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;

        /*
         * Retrieve RX context of current packet, if any.
         */
        first_seg = rxq->pkt_first_seg;
        last_seg = rxq->pkt_last_seg;

        while (nb_rx < nb_pkts) {
        next_desc:
                /*
                 * 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->wb.upper.status_error;
                if (! (staterr & rte_cpu_to_le_32(E1000_RXD_STAT_DD)))
                        break;
                rxd = *rxdp;

                /*
                 * Descriptor done.
                 *
                 * 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 does 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 "
                           "staterr=0x%x data_len=%u",
                           (unsigned) rxq->port_id, (unsigned) rxq->queue_id,
                           (unsigned) rx_id, (unsigned) staterr,
                           (unsigned) rte_le_to_cpu_16(rxd.wb.upper.length));

                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", (unsigned) rxq->port_id,
                                   (unsigned) rxq->queue_id);
                        rte_eth_devices[rxq->port_id].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_igb_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_igb_prefetch(&rx_ring[rx_id]);
                        rte_igb_prefetch(&sw_ring[rx_id]);
                }

                /*
                 * Update RX descriptor with the physical address of the new
                 * data buffer of the new allocated mbuf.
                 */
                rxm = rxe->mbuf;
                rxe->mbuf = nmb;
                dma = rte_cpu_to_le_64(rte_mbuf_data_iova_default(nmb));
                rxdp->read.pkt_addr = dma;
                rxdp->read.hdr_addr = 0;

                /*
                 * Set data length & data buffer address of mbuf.
                 */
                data_len = rte_le_to_cpu_16(rxd.wb.upper.length);
                rxm->data_len = data_len;
                rxm->data_off = RTE_PKTMBUF_HEADROOM;

                /*
                 * 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++;
                        last_seg->next = rxm;
                }

                /*
                 * If this is not the last buffer of the received packet,
                 * update the pointer to the last mbuf of the current scattered
                 * packet and continue to parse the RX ring.
                 */
                if (! (staterr & E1000_RXD_STAT_EOP)) {
                        last_seg = rxm;
                        goto next_desc;
                }

                /*
                 * This is the last buffer of the received packet.
                 * If the CRC is not stripped by the hardware:
                 *   - Subtract the CRC length from the total packet length.
                 *   - If the last buffer only contains the whole CRC or a part
                 *     of it, free the mbuf associated to the last buffer.
                 *     If part of the CRC is also contained in the previous
                 *     mbuf, subtract the length of that CRC part from the
                 *     data length of the previous mbuf.
                 */
                rxm->next = NULL;
                if (unlikely(rxq->crc_len > 0)) {
                        first_seg->pkt_len -= ETHER_CRC_LEN;
                        if (data_len <= ETHER_CRC_LEN) {
                                rte_pktmbuf_free_seg(rxm);
                                first_seg->nb_segs--;
                                last_seg->data_len = (uint16_t)
                                        (last_seg->data_len -
                                         (ETHER_CRC_LEN - data_len));
                                last_seg->next = NULL;
                        } else
                                rxm->data_len =
                                        (uint16_t) (data_len - ETHER_CRC_LEN);
                }

                /*
                 * Initialize the first mbuf of the returned packet:
                 *    - RX port identifier,
                 *    - hardware offload data, if any:
                 *      - RSS flag & hash,
                 *      - IP checksum flag,
                 *      - VLAN TCI, if any,
                 *      - error flags.
                 */
                first_seg->port = rxq->port_id;
                first_seg->hash.rss = rxd.wb.lower.hi_dword.rss;

                /*
                 * The vlan_tci field is only valid when PKT_RX_VLAN is
                 * set in the pkt_flags field and must be in CPU byte order.
                 */
                if ((staterr & rte_cpu_to_le_32(E1000_RXDEXT_STATERR_LB)) &&
                                (rxq->flags & IGB_RXQ_FLAG_LB_BSWAP_VLAN)) {
                        first_seg->vlan_tci =
                                rte_be_to_cpu_16(rxd.wb.upper.vlan);
                } else {
                        first_seg->vlan_tci =
                                rte_le_to_cpu_16(rxd.wb.upper.vlan);
                }
                hlen_type_rss = rte_le_to_cpu_32(rxd.wb.lower.lo_dword.data);
                pkt_flags = rx_desc_hlen_type_rss_to_pkt_flags(rxq, hlen_type_rss);
                pkt_flags = pkt_flags | rx_desc_status_to_pkt_flags(staterr);
                pkt_flags = pkt_flags | rx_desc_error_to_pkt_flags(staterr);
                first_seg->ol_flags = pkt_flags;
                first_seg->packet_type = igb_rxd_pkt_info_to_pkt_type(rxd.wb.
                                        lower.lo_dword.hs_rss.pkt_info);

                /* 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;

                /*
                 * Setup receipt context for a new packet.
                 */
                first_seg = NULL;
        }

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

        /*
         * Save receive context.
         */
        rxq->pkt_first_seg = first_seg;
        rxq->pkt_last_seg = last_seg;

        /*
         * 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 situtation 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",
                           (unsigned) rxq->port_id, (unsigned) rxq->queue_id,
                           (unsigned) rx_id, (unsigned) nb_hold,
                           (unsigned) nb_rx);
                rx_id = (uint16_t) ((rx_id == 0) ?
                                     (rxq->nb_rx_desc - 1) : (rx_id - 1));
                E1000_PCI_REG_WRITE(rxq->rdt_reg_addr, rx_id);
                nb_hold = 0;
        }
        rxq->nb_rx_hold = nb_hold;
        return nb_rx;
}

/*
 * Maximum number of Ring Descriptors.
 *
 * Since RDLEN/TDLEN should be multiple of 128bytes, the number of ring
 * desscriptors should meet the following condition:
 *      (num_ring_desc * sizeof(struct e1000_rx/tx_desc)) % 128 == 0
 */

static void
igb_tx_queue_release_mbufs(struct igb_tx_queue *txq)
{
        unsigned 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
igb_tx_queue_release(struct igb_tx_queue *txq)
{
        if (txq != NULL) {
                igb_tx_queue_release_mbufs(txq);
                rte_free(txq->sw_ring);
                rte_free(txq);
        }
}

void
eth_igb_tx_queue_release(void *txq)
{
        igb_tx_queue_release(txq);
}

static int
igb_tx_done_cleanup(struct igb_tx_queue *txq, uint32_t free_cnt)
{
        struct igb_tx_entry *sw_ring;
        volatile union e1000_adv_tx_desc *txr;
        uint16_t tx_first; /* First segment analyzed. */
        uint16_t tx_id;    /* Current segment being processed. */
        uint16_t tx_last;  /* Last segment in the current packet. */
        uint16_t tx_next;  /* First segment of the next packet. */
        int count;

        if (txq != NULL) {
                count = 0;
                sw_ring = txq->sw_ring;
                txr = txq->tx_ring;

                /*
                 * tx_tail is the last sent packet on the sw_ring. Goto the end
                 * of that packet (the last segment in the packet chain) and
                 * then the next segment will be the start of the oldest segment
                 * in the sw_ring. This is the first packet that will be
                 * attempted to be freed.
                 */

                /* Get last segment in most recently added packet. */
                tx_first = sw_ring[txq->tx_tail].last_id;

                /* Get the next segment, which is the oldest segment in ring. */
                tx_first = sw_ring[tx_first].next_id;

                /* Set the current index to the first. */
                tx_id = tx_first;

                /*
                 * Loop through each packet. For each packet, verify that an
                 * mbuf exists and that the last segment is free. If so, free
                 * it and move on.
                 */
                while (1) {
                        tx_last = sw_ring[tx_id].last_id;

                        if (sw_ring[tx_last].mbuf) {
                                if (txr[tx_last].wb.status &
                                                E1000_TXD_STAT_DD) {
                                        /*
                                         * Increment the number of packets
                                         * freed.
                                         */
                                        count++;

                                        /* Get the start of the next packet. */
                                        tx_next = sw_ring[tx_last].next_id;

                                        /*
                                         * Loop through all segments in a
                                         * packet.
                                         */
                                        do {
                                                rte_pktmbuf_free_seg(sw_ring[tx_id].mbuf);
                                                sw_ring[tx_id].mbuf = NULL;
                                                sw_ring[tx_id].last_id = tx_id;

                                                /* Move to next segemnt. */
                                                tx_id = sw_ring[tx_id].next_id;

                                        } while (tx_id != tx_next);

                                        if (unlikely(count == (int)free_cnt))
                                                break;
                                } else
                                        /*
                                         * mbuf still in use, nothing left to
                                         * free.
                                         */
                                        break;
                        } else {
                                /*
                                 * There are multiple reasons to be here:
                                 * 1) All the packets on the ring have been
                                 *    freed - tx_id is equal to tx_first
                                 *    and some packets have been freed.
                                 *    - Done, exit
                                 * 2) Interfaces has not sent a rings worth of
                                 *    packets yet, so the segment after tail is
                                 *    still empty. Or a previous call to this
                                 *    function freed some of the segments but
                                 *    not all so there is a hole in the list.
                                 *    Hopefully this is a rare case.
                                 *    - Walk the list and find the next mbuf. If
                                 *      there isn't one, then done.
                                 */
                                if (likely((tx_id == tx_first) && (count != 0)))
                                        break;

                                /*
                                 * Walk the list and find the next mbuf, if any.
                                 */
                                do {
                                        /* Move to next segemnt. */
                                        tx_id = sw_ring[tx_id].next_id;

                                        if (sw_ring[tx_id].mbuf)
                                                break;

                                } while (tx_id != tx_first);

                                /*
                                 * Determine why previous loop bailed. If there
                                 * is not an mbuf, done.
                                 */
                                if (sw_ring[tx_id].mbuf == NULL)
                                        break;
                        }
                }
        } else
                count = -ENODEV;

        return count;
}

int
eth_igb_tx_done_cleanup(void *txq, uint32_t free_cnt)
{
        return igb_tx_done_cleanup(txq, free_cnt);
}

static void
igb_reset_tx_queue_stat(struct igb_tx_queue *txq)
{
        txq->tx_head = 0;
        txq->tx_tail = 0;
        txq->ctx_curr = 0;
        memset((void*)&txq->ctx_cache, 0,
                IGB_CTX_NUM * sizeof(struct igb_advctx_info));
}

static void
igb_reset_tx_queue(struct igb_tx_queue *txq, struct rte_eth_dev *dev)
{
        static const union e1000_adv_tx_desc zeroed_desc = {{0}};
        struct igb_tx_entry *txe = txq->sw_ring;
        uint16_t i, prev;
        struct e1000_hw *hw;

        hw = E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);
        /* Zero out HW ring memory */
        for (i = 0; i < txq->nb_tx_desc; i++) {
                txq->tx_ring[i] = zeroed_desc;
        }

        /* Initialize ring entries */
        prev = (uint16_t)(txq->nb_tx_desc - 1);
        for (i = 0; i < txq->nb_tx_desc; i++) {
                volatile union e1000_adv_tx_desc *txd = &(txq->tx_ring[i]);

                txd->wb.status = E1000_TXD_STAT_DD;
                txe[i].mbuf = NULL;
                txe[i].last_id = i;
                txe[prev].next_id = i;
                prev = i;
        }

        txq->txd_type = E1000_ADVTXD_DTYP_DATA;
        /* 82575 specific, each tx queue will use 2 hw contexts */
        if (hw->mac.type == e1000_82575)
                txq->ctx_start = txq->queue_id * IGB_CTX_NUM;

        igb_reset_tx_queue_stat(txq);
}

int
eth_igb_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 igb_tx_queue *txq;
        struct e1000_hw     *hw;
        uint32_t size;

        hw = E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);

        /*
         * Validate number of transmit descriptors.
         * It must not exceed hardware maximum, and must be multiple
         * of E1000_ALIGN.
         */
        if (nb_desc % IGB_TXD_ALIGN != 0 ||
                        (nb_desc > E1000_MAX_RING_DESC) ||
                        (nb_desc < E1000_MIN_RING_DESC)) {
                return -EINVAL;
        }

        /*
         * The tx_free_thresh and tx_rs_thresh values are not used in the 1G
         * driver.
         */
        if (tx_conf->tx_free_thresh != 0)
                PMD_INIT_LOG(INFO, "The tx_free_thresh parameter is not "
                             "used for the 1G driver.");
        if (tx_conf->tx_rs_thresh != 0)
                PMD_INIT_LOG(INFO, "The tx_rs_thresh parameter is not "
                             "used for the 1G driver.");
        if (tx_conf->tx_thresh.wthresh == 0 && hw->mac.type != e1000_82576)
                PMD_INIT_LOG(INFO, "To improve 1G driver performance, "
                             "consider setting the TX WTHRESH value to 4, 8, "
                             "or 16.");

        /* Free memory prior to re-allocation if needed */
        if (dev->data->tx_queues[queue_idx] != NULL) {
                igb_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("ethdev TX queue", sizeof(struct igb_tx_queue),
                                                        RTE_CACHE_LINE_SIZE);
        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.
         */
        size = sizeof(union e1000_adv_tx_desc) * E1000_MAX_RING_DESC;
        tz = rte_eth_dma_zone_reserve(dev, "tx_ring", queue_idx, size,
                                      E1000_ALIGN, socket_id);
        if (tz == NULL) {
                igb_tx_queue_release(txq);
                return -ENOMEM;
        }

        txq->nb_tx_desc = nb_desc;
        txq->pthresh = tx_conf->tx_thresh.pthresh;
        txq->hthresh = tx_conf->tx_thresh.hthresh;
        txq->wthresh = tx_conf->tx_thresh.wthresh;
        if (txq->wthresh > 0 && hw->mac.type == e1000_82576)
                txq->wthresh = 1;
        txq->queue_id = queue_idx;
        txq->reg_idx = (uint16_t)((RTE_ETH_DEV_SRIOV(dev).active == 0) ?
                queue_idx : RTE_ETH_DEV_SRIOV(dev).def_pool_q_idx + queue_idx);
        txq->port_id = dev->data->port_id;

        txq->tdt_reg_addr = E1000_PCI_REG_ADDR(hw, E1000_TDT(txq->reg_idx));
        txq->tx_ring_phys_addr = tz->iova;

        txq->tx_ring = (union e1000_adv_tx_desc *) tz->addr;
        /* Allocate software ring */
        txq->sw_ring = rte_zmalloc("txq->sw_ring",
                                   sizeof(struct igb_tx_entry) * nb_desc,
                                   RTE_CACHE_LINE_SIZE);
        if (txq->sw_ring == NULL) {
                igb_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);

        igb_reset_tx_queue(txq, dev);
        dev->tx_pkt_burst = eth_igb_xmit_pkts;
        dev->tx_pkt_prepare = &eth_igb_prep_pkts;
        dev->data->tx_queues[queue_idx] = txq;

        return 0;
}

static void
igb_rx_queue_release_mbufs(struct igb_rx_queue *rxq)
{
        unsigned 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;
                        }
                }
        }
}

static void
igb_rx_queue_release(struct igb_rx_queue *rxq)
{
        if (rxq != NULL) {
                igb_rx_queue_release_mbufs(rxq);
                rte_free(rxq->sw_ring);
                rte_free(rxq);
        }
}

void
eth_igb_rx_queue_release(void *rxq)
{
        igb_rx_queue_release(rxq);
}

static void
igb_reset_rx_queue(struct igb_rx_queue *rxq)
{
        static const union e1000_adv_rx_desc zeroed_desc = {{0}};
        unsigned i;

        /* Zero out HW ring memory */
        for (i = 0; i < rxq->nb_rx_desc; i++) {
                rxq->rx_ring[i] = zeroed_desc;
        }

        rxq->rx_tail = 0;
        rxq->pkt_first_seg = NULL;
        rxq->pkt_last_seg = NULL;
}

int
eth_igb_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 igb_rx_queue *rxq;
        struct e1000_hw     *hw;
        unsigned int size;

        hw = E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);

        /*
         * Validate number of receive descriptors.
         * It must not exceed hardware maximum, and must be multiple
         * of E1000_ALIGN.
         */
        if (nb_desc % IGB_RXD_ALIGN != 0 ||
                        (nb_desc > E1000_MAX_RING_DESC) ||
                        (nb_desc < E1000_MIN_RING_DESC)) {
                return -EINVAL;
        }

        /* Free memory prior to re-allocation if needed */
        if (dev->data->rx_queues[queue_idx] != NULL) {
                igb_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("ethdev RX queue", sizeof(struct igb_rx_queue),
                          RTE_CACHE_LINE_SIZE);
        if (rxq == NULL)
                return -ENOMEM;
        rxq->mb_pool = mp;
        rxq->nb_rx_desc = nb_desc;
        rxq->pthresh = rx_conf->rx_thresh.pthresh;
        rxq->hthresh = rx_conf->rx_thresh.hthresh;
        rxq->wthresh = rx_conf->rx_thresh.wthresh;
        if (rxq->wthresh > 0 &&
            (hw->mac.type == e1000_82576 || hw->mac.type == e1000_vfadapt_i350))
                rxq->wthresh = 1;
        rxq->drop_en = rx_conf->rx_drop_en;
        rxq->rx_free_thresh = rx_conf->rx_free_thresh;
        rxq->queue_id = queue_idx;
        rxq->reg_idx = (uint16_t)((RTE_ETH_DEV_SRIOV(dev).active == 0) ?
                queue_idx : RTE_ETH_DEV_SRIOV(dev).def_pool_q_idx + queue_idx);
        rxq->port_id = dev->data->port_id;
        rxq->crc_len = (uint8_t) ((dev->data->dev_conf.rxmode.hw_strip_crc) ? 0 :
                                  ETHER_CRC_LEN);

        /*
         *  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.
         */
        size = sizeof(union e1000_adv_rx_desc) * E1000_MAX_RING_DESC;
        rz = rte_eth_dma_zone_reserve(dev, "rx_ring", queue_idx, size,
                                      E1000_ALIGN, socket_id);
        if (rz == NULL) {
                igb_rx_queue_release(rxq);
                return -ENOMEM;
        }
        rxq->rdt_reg_addr = E1000_PCI_REG_ADDR(hw, E1000_RDT(rxq->reg_idx));
        rxq->rdh_reg_addr = E1000_PCI_REG_ADDR(hw, E1000_RDH(rxq->reg_idx));
        rxq->rx_ring_phys_addr = rz->iova;
        rxq->rx_ring = (union e1000_adv_rx_desc *) rz->addr;

        /* Allocate software ring. */
        rxq->sw_ring = rte_zmalloc("rxq->sw_ring",
                                   sizeof(struct igb_rx_entry) * nb_desc,
                                   RTE_CACHE_LINE_SIZE);
        if (rxq->sw_ring == NULL) {
                igb_rx_queue_release(rxq);
                return -ENOMEM;
        }
        PMD_INIT_LOG(DEBUG, "sw_ring=%p hw_ring=%p dma_addr=0x%"PRIx64,
                     rxq->sw_ring, rxq->rx_ring, rxq->rx_ring_phys_addr);

        dev->data->rx_queues[queue_idx] = rxq;
        igb_reset_rx_queue(rxq);

        return 0;
}

uint32_t
eth_igb_rx_queue_count(struct rte_eth_dev *dev, uint16_t rx_queue_id)
{
#define IGB_RXQ_SCAN_INTERVAL 4
        volatile union e1000_adv_rx_desc *rxdp;
        struct igb_rx_queue *rxq;
        uint32_t desc = 0;

        rxq = dev->data->rx_queues[rx_queue_id];
        rxdp = &(rxq->rx_ring[rxq->rx_tail]);

        while ((desc < rxq->nb_rx_desc) &&
                (rxdp->wb.upper.status_error & E1000_RXD_STAT_DD)) {
                desc += IGB_RXQ_SCAN_INTERVAL;
                rxdp += IGB_RXQ_SCAN_INTERVAL;
                if (rxq->rx_tail + desc >= rxq->nb_rx_desc)
                        rxdp = &(rxq->rx_ring[rxq->rx_tail +
                                desc - rxq->nb_rx_desc]);
        }

        return desc;
}

int
eth_igb_rx_descriptor_done(void *rx_queue, uint16_t offset)
{
        volatile union e1000_adv_rx_desc *rxdp;
        struct igb_rx_queue *rxq = rx_queue;
        uint32_t desc;

        if (unlikely(offset >= rxq->nb_rx_desc))
                return 0;
        desc = rxq->rx_tail + offset;
        if (desc >= rxq->nb_rx_desc)
                desc -= rxq->nb_rx_desc;

        rxdp = &rxq->rx_ring[desc];
        return !!(rxdp->wb.upper.status_error & E1000_RXD_STAT_DD);
}

int
eth_igb_rx_descriptor_status(void *rx_queue, uint16_t offset)
{
        struct igb_rx_queue *rxq = rx_queue;
        volatile uint32_t *status;
        uint32_t desc;

        if (unlikely(offset >= rxq->nb_rx_desc))
                return -EINVAL;

        if (offset >= rxq->nb_rx_desc - rxq->nb_rx_hold)
                return RTE_ETH_RX_DESC_UNAVAIL;

        desc = rxq->rx_tail + offset;
        if (desc >= rxq->nb_rx_desc)
                desc -= rxq->nb_rx_desc;

        status = &rxq->rx_ring[desc].wb.upper.status_error;
        if (*status & rte_cpu_to_le_32(E1000_RXD_STAT_DD))
                return RTE_ETH_RX_DESC_DONE;

        return RTE_ETH_RX_DESC_AVAIL;
}

int
eth_igb_tx_descriptor_status(void *tx_queue, uint16_t offset)
{
        struct igb_tx_queue *txq = tx_queue;
        volatile uint32_t *status;
        uint32_t desc;

        if (unlikely(offset >= txq->nb_tx_desc))
                return -EINVAL;

        desc = txq->tx_tail + offset;
        if (desc >= txq->nb_tx_desc)
                desc -= txq->nb_tx_desc;

        status = &txq->tx_ring[desc].wb.status;
        if (*status & rte_cpu_to_le_32(E1000_TXD_STAT_DD))
                return RTE_ETH_TX_DESC_DONE;

        return RTE_ETH_TX_DESC_FULL;
}

void
igb_dev_clear_queues(struct rte_eth_dev *dev)
{
        uint16_t i;
        struct igb_tx_queue *txq;
        struct igb_rx_queue *rxq;

        for (i = 0; i < dev->data->nb_tx_queues; i++) {
                txq = dev->data->tx_queues[i];
                if (txq != NULL) {
                        igb_tx_queue_release_mbufs(txq);
                        igb_reset_tx_queue(txq, dev);
                }
        }

        for (i = 0; i < dev->data->nb_rx_queues; i++) {
                rxq = dev->data->rx_queues[i];
                if (rxq != NULL) {
                        igb_rx_queue_release_mbufs(rxq);
                        igb_reset_rx_queue(rxq);
                }
        }
}

void
igb_dev_free_queues(struct rte_eth_dev *dev)
{
        uint16_t i;

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

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

/**
 * Receive Side Scaling (RSS).
 * See section 7.1.1.7 in the following document:
 *     "Intel 82576 GbE Controller Datasheet" - Revision 2.45 October 2009
 *
 * Principles:
 * The source and destination IP addresses of the IP header and the source and
 * destination ports of TCP/UDP headers, if any, of received packets are hashed
 * against a configurable random key to compute a 32-bit RSS hash result.
 * The seven (7) LSBs of the 32-bit hash result are used as an index into a
 * 128-entry redirection table (RETA).  Each entry of the RETA provides a 3-bit
 * RSS output index which is used as the RX queue index where to store the
 * received packets.
 * The following output is supplied in the RX write-back descriptor:
 *     - 32-bit result of the Microsoft RSS hash function,
 *     - 4-bit RSS type field.
 */

/*
 * RSS random key supplied in section 7.1.1.7.3 of the Intel 82576 datasheet.
 * Used as the default key.
 */
static uint8_t rss_intel_key[40] = {
        0x6D, 0x5A, 0x56, 0xDA, 0x25, 0x5B, 0x0E, 0xC2,
        0x41, 0x67, 0x25, 0x3D, 0x43, 0xA3, 0x8F, 0xB0,
        0xD0, 0xCA, 0x2B, 0xCB, 0xAE, 0x7B, 0x30, 0xB4,
        0x77, 0xCB, 0x2D, 0xA3, 0x80, 0x30, 0xF2, 0x0C,
        0x6A, 0x42, 0xB7, 0x3B, 0xBE, 0xAC, 0x01, 0xFA,
};

static void
igb_rss_disable(struct rte_eth_dev *dev)
{
        struct e1000_hw *hw;
        uint32_t mrqc;

        hw = E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);
        mrqc = E1000_READ_REG(hw, E1000_MRQC);
        mrqc &= ~E1000_MRQC_ENABLE_MASK;
        E1000_WRITE_REG(hw, E1000_MRQC, mrqc);
}

static void
igb_hw_rss_hash_set(struct e1000_hw *hw, struct rte_eth_rss_conf *rss_conf)
{
        uint8_t  *hash_key;
        uint32_t rss_key;
        uint32_t mrqc;
        uint64_t rss_hf;
        uint16_t i;

        hash_key = rss_conf->rss_key;
        if (hash_key != NULL) {
                /* Fill in RSS hash key */
                for (i = 0; i < 10; i++) {
                        rss_key  = hash_key[(i * 4)];
                        rss_key |= hash_key[(i * 4) + 1] << 8;
                        rss_key |= hash_key[(i * 4) + 2] << 16;
                        rss_key |= hash_key[(i * 4) + 3] << 24;
                        E1000_WRITE_REG_ARRAY(hw, E1000_RSSRK(0), i, rss_key);
                }
        }

        /* Set configured hashing protocols in MRQC register */
        rss_hf = rss_conf->rss_hf;
        mrqc = E1000_MRQC_ENABLE_RSS_4Q; /* RSS enabled. */
        if (rss_hf & ETH_RSS_IPV4)
                mrqc |= E1000_MRQC_RSS_FIELD_IPV4;
        if (rss_hf & ETH_RSS_NONFRAG_IPV4_TCP)
                mrqc |= E1000_MRQC_RSS_FIELD_IPV4_TCP;
        if (rss_hf & ETH_RSS_IPV6)
                mrqc |= E1000_MRQC_RSS_FIELD_IPV6;
        if (rss_hf & ETH_RSS_IPV6_EX)
                mrqc |= E1000_MRQC_RSS_FIELD_IPV6_EX;
        if (rss_hf & ETH_RSS_NONFRAG_IPV6_TCP)
                mrqc |= E1000_MRQC_RSS_FIELD_IPV6_TCP;
        if (rss_hf & ETH_RSS_IPV6_TCP_EX)
                mrqc |= E1000_MRQC_RSS_FIELD_IPV6_TCP_EX;
        if (rss_hf & ETH_RSS_NONFRAG_IPV4_UDP)
                mrqc |= E1000_MRQC_RSS_FIELD_IPV4_UDP;
        if (rss_hf & ETH_RSS_NONFRAG_IPV6_UDP)
                mrqc |= E1000_MRQC_RSS_FIELD_IPV6_UDP;
        if (rss_hf & ETH_RSS_IPV6_UDP_EX)
                mrqc |= E1000_MRQC_RSS_FIELD_IPV6_UDP_EX;
        E1000_WRITE_REG(hw, E1000_MRQC, mrqc);
}

int
eth_igb_rss_hash_update(struct rte_eth_dev *dev,
                        struct rte_eth_rss_conf *rss_conf)
{
        struct e1000_hw *hw;
        uint32_t mrqc;
        uint64_t rss_hf;

        hw = E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);

        /*
         * Before changing anything, first check that the update RSS operation
         * does not attempt to disable RSS, if RSS was enabled at
         * initialization time, or does not attempt to enable RSS, if RSS was
         * disabled at initialization time.
         */
        rss_hf = rss_conf->rss_hf & IGB_RSS_OFFLOAD_ALL;
        mrqc = E1000_READ_REG(hw, E1000_MRQC);
        if (!(mrqc & E1000_MRQC_ENABLE_MASK)) { /* RSS disabled */
                if (rss_hf != 0) /* Enable RSS */
                        return -(EINVAL);
                return 0; /* Nothing to do */
        }
        /* RSS enabled */
        if (rss_hf == 0) /* Disable RSS */
                return -(EINVAL);
        igb_hw_rss_hash_set(hw, rss_conf);
        return 0;
}

int eth_igb_rss_hash_conf_get(struct rte_eth_dev *dev,
                              struct rte_eth_rss_conf *rss_conf)
{
        struct e1000_hw *hw;
        uint8_t *hash_key;
        uint32_t rss_key;
        uint32_t mrqc;
        uint64_t rss_hf;
        uint16_t i;

        hw = E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);
        hash_key = rss_conf->rss_key;
        if (hash_key != NULL) {
                /* Return RSS hash key */
                for (i = 0; i < 10; i++) {
                        rss_key = E1000_READ_REG_ARRAY(hw, E1000_RSSRK(0), i);
                        hash_key[(i * 4)] = rss_key & 0x000000FF;
                        hash_key[(i * 4) + 1] = (rss_key >> 8) & 0x000000FF;
                        hash_key[(i * 4) + 2] = (rss_key >> 16) & 0x000000FF;
                        hash_key[(i * 4) + 3] = (rss_key >> 24) & 0x000000FF;
                }
        }

        /* Get RSS functions configured in MRQC register */
        mrqc = E1000_READ_REG(hw, E1000_MRQC);
        if ((mrqc & E1000_MRQC_ENABLE_RSS_4Q) == 0) { /* RSS is disabled */
                rss_conf->rss_hf = 0;
                return 0;
        }
        rss_hf = 0;
        if (mrqc & E1000_MRQC_RSS_FIELD_IPV4)
                rss_hf |= ETH_RSS_IPV4;
        if (mrqc & E1000_MRQC_RSS_FIELD_IPV4_TCP)
                rss_hf |= ETH_RSS_NONFRAG_IPV4_TCP;
        if (mrqc & E1000_MRQC_RSS_FIELD_IPV6)
                rss_hf |= ETH_RSS_IPV6;
        if (mrqc & E1000_MRQC_RSS_FIELD_IPV6_EX)
                rss_hf |= ETH_RSS_IPV6_EX;
        if (mrqc & E1000_MRQC_RSS_FIELD_IPV6_TCP)
                rss_hf |= ETH_RSS_NONFRAG_IPV6_TCP;
        if (mrqc & E1000_MRQC_RSS_FIELD_IPV6_TCP_EX)
                rss_hf |= ETH_RSS_IPV6_TCP_EX;
        if (mrqc & E1000_MRQC_RSS_FIELD_IPV4_UDP)
                rss_hf |= ETH_RSS_NONFRAG_IPV4_UDP;
        if (mrqc & E1000_MRQC_RSS_FIELD_IPV6_UDP)
                rss_hf |= ETH_RSS_NONFRAG_IPV6_UDP;
        if (mrqc & E1000_MRQC_RSS_FIELD_IPV6_UDP_EX)
                rss_hf |= ETH_RSS_IPV6_UDP_EX;
        rss_conf->rss_hf = rss_hf;
        return 0;
}

static void
igb_rss_configure(struct rte_eth_dev *dev)
{
        struct rte_eth_rss_conf rss_conf;
        struct e1000_hw *hw;
        uint32_t shift;
        uint16_t i;

        hw = E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);

        /* Fill in redirection table. */
        shift = (hw->mac.type == e1000_82575) ? 6 : 0;
        for (i = 0; i < 128; i++) {
                union e1000_reta {
                        uint32_t dword;
                        uint8_t  bytes[4];
                } reta;
                uint8_t q_idx;

                q_idx = (uint8_t) ((dev->data->nb_rx_queues > 1) ?
                                   i % dev->data->nb_rx_queues : 0);
                reta.bytes[i & 3] = (uint8_t) (q_idx << shift);
                if ((i & 3) == 3)
                        E1000_WRITE_REG(hw, E1000_RETA(i >> 2), reta.dword);
        }

        /*
         * Configure the RSS key and the RSS protocols used to compute
         * the RSS hash of input packets.
         */
        rss_conf = dev->data->dev_conf.rx_adv_conf.rss_conf;
        if ((rss_conf.rss_hf & IGB_RSS_OFFLOAD_ALL) == 0) {
                igb_rss_disable(dev);
                return;
        }
        if (rss_conf.rss_key == NULL)
                rss_conf.rss_key = rss_intel_key; /* Default hash key */
        igb_hw_rss_hash_set(hw, &rss_conf);
}

/*
 * Check if the mac type support VMDq or not.
 * Return 1 if it supports, otherwise, return 0.
 */
static int
igb_is_vmdq_supported(const struct rte_eth_dev *dev)
{
        const struct e1000_hw *hw = E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);

        switch (hw->mac.type) {
        case e1000_82576:
        case e1000_82580:
        case e1000_i350:
                return 1;
        case e1000_82540:
        case e1000_82541:
        case e1000_82542:
        case e1000_82543:
        case e1000_82544:
        case e1000_82545:
        case e1000_82546:
        case e1000_82547:
        case e1000_82571:
        case e1000_82572:
        case e1000_82573:
        case e1000_82574:
        case e1000_82583:
        case e1000_i210:
        case e1000_i211:
        default:
                PMD_INIT_LOG(ERR, "Cannot support VMDq feature");
                return 0;
        }
}

static int
igb_vmdq_rx_hw_configure(struct rte_eth_dev *dev)
{
        struct rte_eth_vmdq_rx_conf *cfg;
        struct e1000_hw *hw;
        uint32_t mrqc, vt_ctl, vmolr, rctl;
        int i;

        PMD_INIT_FUNC_TRACE();

        hw = E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);
        cfg = &dev->data->dev_conf.rx_adv_conf.vmdq_rx_conf;

        /* Check if mac type can support VMDq, return value of 0 means NOT support */
        if (igb_is_vmdq_supported(dev) == 0)
                return -1;

        igb_rss_disable(dev);

        /* RCTL: eanble VLAN filter */
        rctl = E1000_READ_REG(hw, E1000_RCTL);
        rctl |= E1000_RCTL_VFE;
        E1000_WRITE_REG(hw, E1000_RCTL, rctl);

        /* MRQC: enable vmdq */
        mrqc = E1000_READ_REG(hw, E1000_MRQC);
        mrqc |= E1000_MRQC_ENABLE_VMDQ;
        E1000_WRITE_REG(hw, E1000_MRQC, mrqc);

        /* VTCTL:  pool selection according to VLAN tag */
        vt_ctl = E1000_READ_REG(hw, E1000_VT_CTL);
        if (cfg->enable_default_pool)
                vt_ctl |= (cfg->default_pool << E1000_VT_CTL_DEFAULT_POOL_SHIFT);
        vt_ctl |= E1000_VT_CTL_IGNORE_MAC;
        E1000_WRITE_REG(hw, E1000_VT_CTL, vt_ctl);

        for (i = 0; i < E1000_VMOLR_SIZE; i++) {
                vmolr = E1000_READ_REG(hw, E1000_VMOLR(i));
                vmolr &= ~(E1000_VMOLR_AUPE | E1000_VMOLR_ROMPE |
                        E1000_VMOLR_ROPE | E1000_VMOLR_BAM |
                        E1000_VMOLR_MPME);

                if (cfg->rx_mode & ETH_VMDQ_ACCEPT_UNTAG)
                        vmolr |= E1000_VMOLR_AUPE;
                if (cfg->rx_mode & ETH_VMDQ_ACCEPT_HASH_MC)
                        vmolr |= E1000_VMOLR_ROMPE;
                if (cfg->rx_mode & ETH_VMDQ_ACCEPT_HASH_UC)
                        vmolr |= E1000_VMOLR_ROPE;
                if (cfg->rx_mode & ETH_VMDQ_ACCEPT_BROADCAST)
                        vmolr |= E1000_VMOLR_BAM;
                if (cfg->rx_mode & ETH_VMDQ_ACCEPT_MULTICAST)
                        vmolr |= E1000_VMOLR_MPME;

                E1000_WRITE_REG(hw, E1000_VMOLR(i), vmolr);
        }

        /*
         * VMOLR: set STRVLAN as 1 if IGMAC in VTCTL is set as 1
         * Both 82576 and 82580 support it
         */
        if (hw->mac.type != e1000_i350) {
                for (i = 0; i < E1000_VMOLR_SIZE; i++) {
                        vmolr = E1000_READ_REG(hw, E1000_VMOLR(i));
                        vmolr |= E1000_VMOLR_STRVLAN;
                        E1000_WRITE_REG(hw, E1000_VMOLR(i), vmolr);
                }
        }

        /* VFTA - enable all vlan filters */
        for (i = 0; i < IGB_VFTA_SIZE; i++)
                E1000_WRITE_REG(hw, (E1000_VFTA+(i*4)), UINT32_MAX);

        /* VFRE: 8 pools enabling for rx, both 82576 and i350 support it */
        if (hw->mac.type != e1000_82580)
                E1000_WRITE_REG(hw, E1000_VFRE, E1000_MBVFICR_VFREQ_MASK);

        /*
         * RAH/RAL - allow pools to read specific mac addresses
         * In this case, all pools should be able to read from mac addr 0
         */
        E1000_WRITE_REG(hw, E1000_RAH(0), (E1000_RAH_AV | UINT16_MAX));
        E1000_WRITE_REG(hw, E1000_RAL(0), UINT32_MAX);

        /* VLVF: set up filters for vlan tags as configured */
        for (i = 0; i < cfg->nb_pool_maps; i++) {
                /* set vlan id in VF register and set the valid bit */
                E1000_WRITE_REG(hw, E1000_VLVF(i), (E1000_VLVF_VLANID_ENABLE | \
                        (cfg->pool_map[i].vlan_id & ETH_VLAN_ID_MAX) | \
                        ((cfg->pool_map[i].pools << E1000_VLVF_POOLSEL_SHIFT ) & \
                        E1000_VLVF_POOLSEL_MASK)));
        }

        E1000_WRITE_FLUSH(hw);

        return 0;
}


/*********************************************************************
 *
 *  Enable receive unit.
 *
 **********************************************************************/

static int
igb_alloc_rx_queue_mbufs(struct igb_rx_queue *rxq)
{
        struct igb_rx_entry *rxe = rxq->sw_ring;
        uint64_t dma_addr;
        unsigned i;

        /* Initialize software ring entries. */
        for (i = 0; i < rxq->nb_rx_desc; i++) {
                volatile union e1000_adv_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=%hu", rxq->queue_id);
                        return -ENOMEM;
                }
                dma_addr =
                        rte_cpu_to_le_64(rte_mbuf_data_iova_default(mbuf));
                rxd = &rxq->rx_ring[i];
                rxd->read.hdr_addr = 0;
                rxd->read.pkt_addr = dma_addr;
                rxe[i].mbuf = mbuf;
        }

        return 0;
}

#define E1000_MRQC_DEF_Q_SHIFT               (3)
static int
igb_dev_mq_rx_configure(struct rte_eth_dev *dev)
{
        struct e1000_hw *hw =
                E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);
        uint32_t mrqc;

        if (RTE_ETH_DEV_SRIOV(dev).active == ETH_8_POOLS) {
                /*
                 * SRIOV active scheme
                 * FIXME if support RSS together with VMDq & SRIOV
                 */
                mrqc = E1000_MRQC_ENABLE_VMDQ;
                /* 011b Def_Q ignore, according to VT_CTL.DEF_PL */
                mrqc |= 0x3 << E1000_MRQC_DEF_Q_SHIFT;
                E1000_WRITE_REG(hw, E1000_MRQC, mrqc);
        } else if(RTE_ETH_DEV_SRIOV(dev).active == 0) {
                /*
                 * SRIOV inactive scheme
                 */
                switch (dev->data->dev_conf.rxmode.mq_mode) {
                        case ETH_MQ_RX_RSS:
                                igb_rss_configure(dev);
                                break;
                        case ETH_MQ_RX_VMDQ_ONLY:
                                /*Configure general VMDQ only RX parameters*/
                                igb_vmdq_rx_hw_configure(dev);
                                break;
                        case ETH_MQ_RX_NONE:
                                /* if mq_mode is none, disable rss mode.*/
                        default:
                                igb_rss_disable(dev);
                                break;
                }
        }

        return 0;
}

int
eth_igb_rx_init(struct rte_eth_dev *dev)
{
        struct e1000_hw     *hw;
        struct igb_rx_queue *rxq;
        uint32_t rctl;
        uint32_t rxcsum;
        uint32_t srrctl;
        uint16_t buf_size;
        uint16_t rctl_bsize;
        uint16_t i;
        int ret;

        hw = E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);
        srrctl = 0;

        /*
         * Make sure receives are disabled while setting
         * up the descriptor ring.
         */
        rctl = E1000_READ_REG(hw, E1000_RCTL);
        E1000_WRITE_REG(hw, E1000_RCTL, rctl & ~E1000_RCTL_EN);

        /*
         * Configure support of jumbo frames, if any.
         */
        if (dev->data->dev_conf.rxmode.jumbo_frame == 1) {
                rctl |= E1000_RCTL_LPE;

                /*
                 * Set maximum packet length by default, and might be updated
                 * together with enabling/disabling dual VLAN.
                 */
                E1000_WRITE_REG(hw, E1000_RLPML,
                        dev->data->dev_conf.rxmode.max_rx_pkt_len +
                                                VLAN_TAG_SIZE);
        } else
                rctl &= ~E1000_RCTL_LPE;

        /* Configure and enable each RX queue. */
        rctl_bsize = 0;
        dev->rx_pkt_burst = eth_igb_recv_pkts;
        for (i = 0; i < dev->data->nb_rx_queues; i++) {
                uint64_t bus_addr;
                uint32_t rxdctl;

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

                rxq->flags = 0;
                /*
                 * i350 and i354 vlan packets have vlan tags byte swapped.
                 */
                if (hw->mac.type == e1000_i350 || hw->mac.type == e1000_i354) {
                        rxq->flags |= IGB_RXQ_FLAG_LB_BSWAP_VLAN;
                        PMD_INIT_LOG(DEBUG, "IGB rx vlan bswap required");
                } else {
                        PMD_INIT_LOG(DEBUG, "IGB rx vlan bswap not required");
                }

                /* Allocate buffers for descriptor rings and set up queue */
                ret = igb_alloc_rx_queue_mbufs(rxq);
                if (ret)
                        return ret;

                /*
                 * Reset crc_len in case it was changed after queue setup by a
                 *  call to configure
                 */
                rxq->crc_len =
                        (uint8_t)(dev->data->dev_conf.rxmode.hw_strip_crc ?
                                                        0 : ETHER_CRC_LEN);

                bus_addr = rxq->rx_ring_phys_addr;
                E1000_WRITE_REG(hw, E1000_RDLEN(rxq->reg_idx),
                                rxq->nb_rx_desc *
                                sizeof(union e1000_adv_rx_desc));
                E1000_WRITE_REG(hw, E1000_RDBAH(rxq->reg_idx),
                                (uint32_t)(bus_addr >> 32));
                E1000_WRITE_REG(hw, E1000_RDBAL(rxq->reg_idx), (uint32_t)bus_addr);

                srrctl = E1000_SRRCTL_DESCTYPE_ADV_ONEBUF;

                /*
                 * Configure RX buffer size.
                 */
                buf_size = (uint16_t)(rte_pktmbuf_data_room_size(rxq->mb_pool) -
                        RTE_PKTMBUF_HEADROOM);
                if (buf_size >= 1024) {
                        /*
                         * Configure the BSIZEPACKET field of the SRRCTL
                         * register of the queue.
                         * Value is in 1 KB resolution, from 1 KB to 127 KB.
                         * If this field is equal to 0b, then RCTL.BSIZE
                         * determines the RX packet buffer size.
                         */
                        srrctl |= ((buf_size >> E1000_SRRCTL_BSIZEPKT_SHIFT) &
                                   E1000_SRRCTL_BSIZEPKT_MASK);
                        buf_size = (uint16_t) ((srrctl &
                                                E1000_SRRCTL_BSIZEPKT_MASK) <<
                                               E1000_SRRCTL_BSIZEPKT_SHIFT);

                        /* It adds dual VLAN length for supporting dual VLAN */
                        if ((dev->data->dev_conf.rxmode.max_rx_pkt_len +
                                                2 * VLAN_TAG_SIZE) > buf_size){
                                if (!dev->data->scattered_rx)
                                        PMD_INIT_LOG(DEBUG,
                                                     "forcing scatter mode");
                                dev->rx_pkt_burst = eth_igb_recv_scattered_pkts;
                                dev->data->scattered_rx = 1;
                        }
                } else {
                        /*
                         * Use BSIZE field of the device RCTL register.
                         */
                        if ((rctl_bsize == 0) || (rctl_bsize > buf_size))
                                rctl_bsize = buf_size;
                        if (!dev->data->scattered_rx)
                                PMD_INIT_LOG(DEBUG, "forcing scatter mode");
                        dev->rx_pkt_burst = eth_igb_recv_scattered_pkts;
                        dev->data->scattered_rx = 1;
                }

                /* Set if packets are dropped when no descriptors available */
                if (rxq->drop_en)
                        srrctl |= E1000_SRRCTL_DROP_EN;

                E1000_WRITE_REG(hw, E1000_SRRCTL(rxq->reg_idx), srrctl);

                /* Enable this RX queue. */
                rxdctl = E1000_READ_REG(hw, E1000_RXDCTL(rxq->reg_idx));
                rxdctl |= E1000_RXDCTL_QUEUE_ENABLE;
                rxdctl &= 0xFFF00000;
                rxdctl |= (rxq->pthresh & 0x1F);
                rxdctl |= ((rxq->hthresh & 0x1F) << 8);
                rxdctl |= ((rxq->wthresh & 0x1F) << 16);
                E1000_WRITE_REG(hw, E1000_RXDCTL(rxq->reg_idx), rxdctl);
        }

        if (dev->data->dev_conf.rxmode.enable_scatter) {
                if (!dev->data->scattered_rx)
                        PMD_INIT_LOG(DEBUG, "forcing scatter mode");
                dev->rx_pkt_burst = eth_igb_recv_scattered_pkts;
                dev->data->scattered_rx = 1;
        }

        /*
         * Setup BSIZE field of RCTL register, if needed.
         * Buffer sizes >= 1024 are not [supposed to be] setup in the RCTL
         * register, since the code above configures the SRRCTL register of
         * the RX queue in such a case.
         * All configurable sizes are:
         * 16384: rctl |= (E1000_RCTL_SZ_16384 | E1000_RCTL_BSEX);
         *  8192: rctl |= (E1000_RCTL_SZ_8192  | E1000_RCTL_BSEX);
         *  4096: rctl |= (E1000_RCTL_SZ_4096  | E1000_RCTL_BSEX);
         *  2048: rctl |= E1000_RCTL_SZ_2048;
         *  1024: rctl |= E1000_RCTL_SZ_1024;
         *   512: rctl |= E1000_RCTL_SZ_512;
         *   256: rctl |= E1000_RCTL_SZ_256;
         */
        if (rctl_bsize > 0) {
                if (rctl_bsize >= 512) /* 512 <= buf_size < 1024 - use 512 */
                        rctl |= E1000_RCTL_SZ_512;
                else /* 256 <= buf_size < 512 - use 256 */
                        rctl |= E1000_RCTL_SZ_256;
        }

        /*
         * Configure RSS if device configured with multiple RX queues.
         */
        igb_dev_mq_rx_configure(dev);

        /* Update the rctl since igb_dev_mq_rx_configure may change its value */
        rctl |= E1000_READ_REG(hw, E1000_RCTL);

        /*
         * Setup the Checksum Register.
         * Receive Full-Packet Checksum Offload is mutually exclusive with RSS.
         */
        rxcsum = E1000_READ_REG(hw, E1000_RXCSUM);
        rxcsum |= E1000_RXCSUM_PCSD;

        /* Enable both L3/L4 rx checksum offload */
        if (dev->data->dev_conf.rxmode.hw_ip_checksum)
                rxcsum |= (E1000_RXCSUM_IPOFL | E1000_RXCSUM_TUOFL |
                                E1000_RXCSUM_CRCOFL);
        else
                rxcsum &= ~(E1000_RXCSUM_IPOFL | E1000_RXCSUM_TUOFL |
                                E1000_RXCSUM_CRCOFL);
        E1000_WRITE_REG(hw, E1000_RXCSUM, rxcsum);

        /* Setup the Receive Control Register. */
        if (dev->data->dev_conf.rxmode.hw_strip_crc) {
                rctl |= E1000_RCTL_SECRC; /* Strip Ethernet CRC. */

                /* set STRCRC bit in all queues */
                if (hw->mac.type == e1000_i350 ||
                    hw->mac.type == e1000_i210 ||
                    hw->mac.type == e1000_i211 ||
                    hw->mac.type == e1000_i354) {
                        for (i = 0; i < dev->data->nb_rx_queues; i++) {
                                rxq = dev->data->rx_queues[i];
                                uint32_t dvmolr = E1000_READ_REG(hw,
                                        E1000_DVMOLR(rxq->reg_idx));
                                dvmolr |= E1000_DVMOLR_STRCRC;
                                E1000_WRITE_REG(hw, E1000_DVMOLR(rxq->reg_idx), dvmolr);
                        }
                }
        } else {
                rctl &= ~E1000_RCTL_SECRC; /* Do not Strip Ethernet CRC. */

                /* clear STRCRC bit in all queues */
                if (hw->mac.type == e1000_i350 ||
                    hw->mac.type == e1000_i210 ||
                    hw->mac.type == e1000_i211 ||
                    hw->mac.type == e1000_i354) {
                        for (i = 0; i < dev->data->nb_rx_queues; i++) {
                                rxq = dev->data->rx_queues[i];
                                uint32_t dvmolr = E1000_READ_REG(hw,
                                        E1000_DVMOLR(rxq->reg_idx));
                                dvmolr &= ~E1000_DVMOLR_STRCRC;
                                E1000_WRITE_REG(hw, E1000_DVMOLR(rxq->reg_idx), dvmolr);
                        }
                }
        }

        rctl &= ~(3 << E1000_RCTL_MO_SHIFT);
        rctl |= E1000_RCTL_EN | E1000_RCTL_BAM | E1000_RCTL_LBM_NO |
                E1000_RCTL_RDMTS_HALF |
                (hw->mac.mc_filter_type << E1000_RCTL_MO_SHIFT);

        /* Make sure VLAN Filters are off. */
        if (dev->data->dev_conf.rxmode.mq_mode != ETH_MQ_RX_VMDQ_ONLY)
                rctl &= ~E1000_RCTL_VFE;
        /* Don't store bad packets. */
        rctl &= ~E1000_RCTL_SBP;

        /* Enable Receives. */
        E1000_WRITE_REG(hw, E1000_RCTL, rctl);

        /*
         * Setup the HW Rx Head and Tail Descriptor Pointers.
         * This needs to be done after enable.
         */
        for (i = 0; i < dev->data->nb_rx_queues; i++) {
                rxq = dev->data->rx_queues[i];
                E1000_WRITE_REG(hw, E1000_RDH(rxq->reg_idx), 0);
                E1000_WRITE_REG(hw, E1000_RDT(rxq->reg_idx), rxq->nb_rx_desc - 1);
        }

        return 0;
}

/*********************************************************************
 *
 *  Enable transmit unit.
 *
 **********************************************************************/
void
eth_igb_tx_init(struct rte_eth_dev *dev)
{
        struct e1000_hw     *hw;
        struct igb_tx_queue *txq;
        uint32_t tctl;
        uint32_t txdctl;
        uint16_t i;

        hw = E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);

        /* Setup the Base and Length of the Tx Descriptor Rings. */
        for (i = 0; i < dev->data->nb_tx_queues; i++) {
                uint64_t bus_addr;
                txq = dev->data->tx_queues[i];
                bus_addr = txq->tx_ring_phys_addr;

                E1000_WRITE_REG(hw, E1000_TDLEN(txq->reg_idx),
                                txq->nb_tx_desc *
                                sizeof(union e1000_adv_tx_desc));
                E1000_WRITE_REG(hw, E1000_TDBAH(txq->reg_idx),
                                (uint32_t)(bus_addr >> 32));
                E1000_WRITE_REG(hw, E1000_TDBAL(txq->reg_idx), (uint32_t)bus_addr);

                /* Setup the HW Tx Head and Tail descriptor pointers. */
                E1000_WRITE_REG(hw, E1000_TDT(txq->reg_idx), 0);
                E1000_WRITE_REG(hw, E1000_TDH(txq->reg_idx), 0);

                /* Setup Transmit threshold registers. */
                txdctl = E1000_READ_REG(hw, E1000_TXDCTL(txq->reg_idx));
                txdctl |= txq->pthresh & 0x1F;
                txdctl |= ((txq->hthresh & 0x1F) << 8);
                txdctl |= ((txq->wthresh & 0x1F) << 16);
                txdctl |= E1000_TXDCTL_QUEUE_ENABLE;
                E1000_WRITE_REG(hw, E1000_TXDCTL(txq->reg_idx), txdctl);
        }

        /* Program the Transmit Control Register. */
        tctl = E1000_READ_REG(hw, E1000_TCTL);
        tctl &= ~E1000_TCTL_CT;
        tctl |= (E1000_TCTL_PSP | E1000_TCTL_RTLC | E1000_TCTL_EN |
                 (E1000_COLLISION_THRESHOLD << E1000_CT_SHIFT));

        e1000_config_collision_dist(hw);

        /* This write will effectively turn on the transmit unit. */
        E1000_WRITE_REG(hw, E1000_TCTL, tctl);
}

/*********************************************************************
 *
 *  Enable VF receive unit.
 *
 **********************************************************************/
int
eth_igbvf_rx_init(struct rte_eth_dev *dev)
{
        struct e1000_hw     *hw;
        struct igb_rx_queue *rxq;
        uint32_t srrctl;
        uint16_t buf_size;
        uint16_t rctl_bsize;
        uint16_t i;
        int ret;

        hw = E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);

        /* setup MTU */
        e1000_rlpml_set_vf(hw,
                (uint16_t)(dev->data->dev_conf.rxmode.max_rx_pkt_len +
                VLAN_TAG_SIZE));

        /* Configure and enable each RX queue. */
        rctl_bsize = 0;
        dev->rx_pkt_burst = eth_igb_recv_pkts;
        for (i = 0; i < dev->data->nb_rx_queues; i++) {
                uint64_t bus_addr;
                uint32_t rxdctl;

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

                rxq->flags = 0;
                /*
                 * i350VF LB vlan packets have vlan tags byte swapped.
                 */
                if (hw->mac.type == e1000_vfadapt_i350) {
                        rxq->flags |= IGB_RXQ_FLAG_LB_BSWAP_VLAN;
                        PMD_INIT_LOG(DEBUG, "IGB rx vlan bswap required");
                } else {
                        PMD_INIT_LOG(DEBUG, "IGB rx vlan bswap not required");
                }

                /* Allocate buffers for descriptor rings and set up queue */
                ret = igb_alloc_rx_queue_mbufs(rxq);
                if (ret)
                        return ret;

                bus_addr = rxq->rx_ring_phys_addr;
                E1000_WRITE_REG(hw, E1000_RDLEN(i),
                                rxq->nb_rx_desc *
                                sizeof(union e1000_adv_rx_desc));
                E1000_WRITE_REG(hw, E1000_RDBAH(i),
                                (uint32_t)(bus_addr >> 32));
                E1000_WRITE_REG(hw, E1000_RDBAL(i), (uint32_t)bus_addr);

                srrctl = E1000_SRRCTL_DESCTYPE_ADV_ONEBUF;

                /*
                 * Configure RX buffer size.
                 */
                buf_size = (uint16_t)(rte_pktmbuf_data_room_size(rxq->mb_pool) -
                        RTE_PKTMBUF_HEADROOM);
                if (buf_size >= 1024) {
                        /*
                         * Configure the BSIZEPACKET field of the SRRCTL
                         * register of the queue.
                         * Value is in 1 KB resolution, from 1 KB to 127 KB.
                         * If this field is equal to 0b, then RCTL.BSIZE
                         * determines the RX packet buffer size.
                         */
                        srrctl |= ((buf_size >> E1000_SRRCTL_BSIZEPKT_SHIFT) &
                                   E1000_SRRCTL_BSIZEPKT_MASK);
                        buf_size = (uint16_t) ((srrctl &
                                                E1000_SRRCTL_BSIZEPKT_MASK) <<
                                               E1000_SRRCTL_BSIZEPKT_SHIFT);

                        /* It adds dual VLAN length for supporting dual VLAN */
                        if ((dev->data->dev_conf.rxmode.max_rx_pkt_len +
                                                2 * VLAN_TAG_SIZE) > buf_size){
                                if (!dev->data->scattered_rx)
                                        PMD_INIT_LOG(DEBUG,
                                                     "forcing scatter mode");
                                dev->rx_pkt_burst = eth_igb_recv_scattered_pkts;
                                dev->data->scattered_rx = 1;
                        }
                } else {
                        /*
                         * Use BSIZE field of the device RCTL register.
                         */
                        if ((rctl_bsize == 0) || (rctl_bsize > buf_size))
                                rctl_bsize = buf_size;
                        if (!dev->data->scattered_rx)
                                PMD_INIT_LOG(DEBUG, "forcing scatter mode");
                        dev->rx_pkt_burst = eth_igb_recv_scattered_pkts;
                        dev->data->scattered_rx = 1;
                }

                /* Set if packets are dropped when no descriptors available */
                if (rxq->drop_en)
                        srrctl |= E1000_SRRCTL_DROP_EN;

                E1000_WRITE_REG(hw, E1000_SRRCTL(i), srrctl);

                /* Enable this RX queue. */
                rxdctl = E1000_READ_REG(hw, E1000_RXDCTL(i));
                rxdctl |= E1000_RXDCTL_QUEUE_ENABLE;
                rxdctl &= 0xFFF00000;
                rxdctl |= (rxq->pthresh & 0x1F);
                rxdctl |= ((rxq->hthresh & 0x1F) << 8);
                if (hw->mac.type == e1000_vfadapt) {
                        /*
                         * Workaround of 82576 VF Erratum
                         * force set WTHRESH to 1
                         * to avoid Write-Back not triggered sometimes
                         */
                        rxdctl |= 0x10000;
                        PMD_INIT_LOG(DEBUG, "Force set RX WTHRESH to 1 !");
                }
                else
                        rxdctl |= ((rxq->wthresh & 0x1F) << 16);
                E1000_WRITE_REG(hw, E1000_RXDCTL(i), rxdctl);
        }

        if (dev->data->dev_conf.rxmode.enable_scatter) {
                if (!dev->data->scattered_rx)
                        PMD_INIT_LOG(DEBUG, "forcing scatter mode");
                dev->rx_pkt_burst = eth_igb_recv_scattered_pkts;
                dev->data->scattered_rx = 1;
        }

        /*
         * Setup the HW Rx Head and Tail Descriptor Pointers.
         * This needs to be done after enable.
         */
        for (i = 0; i < dev->data->nb_rx_queues; i++) {
                rxq = dev->data->rx_queues[i];
                E1000_WRITE_REG(hw, E1000_RDH(i), 0);
                E1000_WRITE_REG(hw, E1000_RDT(i), rxq->nb_rx_desc - 1);
        }

        return 0;
}

/*********************************************************************
 *
 *  Enable VF transmit unit.
 *
 **********************************************************************/
void
eth_igbvf_tx_init(struct rte_eth_dev *dev)
{
        struct e1000_hw     *hw;
        struct igb_tx_queue *txq;
        uint32_t txdctl;
        uint16_t i;

        hw = E1000_DEV_PRIVATE_TO_HW(dev->data->dev_private);

        /* Setup the Base and Length of the Tx Descriptor Rings. */
        for (i = 0; i < dev->data->nb_tx_queues; i++) {
                uint64_t bus_addr;

                txq = dev->data->tx_queues[i];
                bus_addr = txq->tx_ring_phys_addr;
                E1000_WRITE_REG(hw, E1000_TDLEN(i),
                                txq->nb_tx_desc *
                                sizeof(union e1000_adv_tx_desc));
                E1000_WRITE_REG(hw, E1000_TDBAH(i),
                                (uint32_t)(bus_addr >> 32));
                E1000_WRITE_REG(hw, E1000_TDBAL(i), (uint32_t)bus_addr);

                /* Setup the HW Tx Head and Tail descriptor pointers. */
                E1000_WRITE_REG(hw, E1000_TDT(i), 0);
                E1000_WRITE_REG(hw, E1000_TDH(i), 0);

                /* Setup Transmit threshold registers. */
                txdctl = E1000_READ_REG(hw, E1000_TXDCTL(i));
                txdctl |= txq->pthresh & 0x1F;
                txdctl |= ((txq->hthresh & 0x1F) << 8);
                if (hw->mac.type == e1000_82576) {
                        /*
                         * Workaround of 82576 VF Erratum
                         * force set WTHRESH to 1
                         * to avoid Write-Back not triggered sometimes
                         */
                        txdctl |= 0x10000;
                        PMD_INIT_LOG(DEBUG, "Force set TX WTHRESH to 1 !");
                }
                else
                        txdctl |= ((txq->wthresh & 0x1F) << 16);
                txdctl |= E1000_TXDCTL_QUEUE_ENABLE;
                E1000_WRITE_REG(hw, E1000_TXDCTL(i), txdctl);
        }

}

void
igb_rxq_info_get(struct rte_eth_dev *dev, uint16_t queue_id,
        struct rte_eth_rxq_info *qinfo)
{
        struct igb_rx_queue *rxq;

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

        qinfo->mp = rxq->mb_pool;
        qinfo->scattered_rx = dev->data->scattered_rx;
        qinfo->nb_desc = rxq->nb_rx_desc;

        qinfo->conf.rx_free_thresh = rxq->rx_free_thresh;
        qinfo->conf.rx_drop_en = rxq->drop_en;
}

void
igb_txq_info_get(struct rte_eth_dev *dev, uint16_t queue_id,
        struct rte_eth_txq_info *qinfo)
{
        struct igb_tx_queue *txq;

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

        qinfo->nb_desc = txq->nb_tx_desc;

        qinfo->conf.tx_thresh.pthresh = txq->pthresh;
        qinfo->conf.tx_thresh.hthresh = txq->hthresh;
        qinfo->conf.tx_thresh.wthresh = txq->wthresh;
}