/* SPDX-License-Identifier: BSD-3-Clause
 * Copyright(c) 2019 Cesnet
 * Copyright(c) 2019 Netcope Technologies, a.s. <info@netcope.com>
 * All rights reserved.
 */

#ifndef _NFB_RX_H_
#define _NFB_RX_H_

#include <nfb/nfb.h>
#include <nfb/ndp.h>

#include <rte_mbuf.h>
#include <rte_mbuf_dyn.h>
#include <rte_ethdev.h>

#define NFB_TIMESTAMP_FLAG (1 << 0)

extern uint64_t nfb_timestamp_rx_dynflag;
extern int nfb_timestamp_dynfield_offset;

static inline rte_mbuf_timestamp_t *
nfb_timestamp_dynfield(struct rte_mbuf *mbuf)
{
        return RTE_MBUF_DYNFIELD(mbuf,
                nfb_timestamp_dynfield_offset, rte_mbuf_timestamp_t *);
}

struct ndp_rx_queue {
        struct nfb_device *nfb;      /* nfb dev structure */
        struct ndp_queue *queue;     /* rx queue */
        uint16_t rx_queue_id;        /* index */
        uint8_t in_port;             /* port */
        uint8_t flags;               /* setup flags */

        struct rte_mempool *mb_pool; /* memory pool to allocate packets */
        uint16_t buf_size;           /* mbuf size */

        volatile uint64_t rx_pkts;   /* packets read */
        volatile uint64_t rx_bytes;  /* bytes read */
        volatile uint64_t err_pkts;  /* erroneous packets */
};

/**
 * Initialize ndp_rx_queue structure
 *
 * @param nfb
 *   Pointer to nfb device structure.
 * @param rx_queue_id
 *   RX queue index.
 * @param port_id
 *   Device [external] port identifier.
 * @param mb_pool
 *   Memory pool for buffer allocations.
 * @param[out] rxq
 *   Pointer to ndp_rx_queue output structure
 * @return
 *   0 on success, a negative errno value otherwise.
 */
int
nfb_eth_rx_queue_init(struct nfb_device *nfb,
        uint16_t rx_queue_id,
        uint16_t port_id,
        struct rte_mempool *mb_pool,
        struct ndp_rx_queue *rxq);

/**
 * DPDK callback to setup a RX queue for use.
 *
 * @param dev
 *   Pointer to Ethernet device structure.
 * @param idx
 *   RX queue index.
 * @param desc
 *   Number of descriptors to configure in queue.
 * @param socket
 *   NUMA socket on which memory must be allocated.
 * @param[in] conf
 *   Thresholds parameters.
 * @param mb_pool
 *   Memory pool for buffer allocations.
 *
 * @return
 *   0 on success, a negative errno value otherwise.
 */
int
nfb_eth_rx_queue_setup(struct rte_eth_dev *dev,
        uint16_t rx_queue_id,
        uint16_t nb_rx_desc __rte_unused,
        unsigned int socket_id,
        const struct rte_eth_rxconf *rx_conf __rte_unused,
        struct rte_mempool *mb_pool);

/**
 * DPDK callback to release a RX queue.
 *
 * @param dpdk_rxq
 *   Generic RX queue pointer.
 */
void
nfb_eth_rx_queue_release(void *q);

/**
 * Start traffic on Rx queue.
 *
 * @param dev
 *   Pointer to Ethernet device structure.
 * @param txq_id
 *   RX queue index.
 * @return
 *   0 on success, a negative errno value otherwise.
 */
int
nfb_eth_rx_queue_start(struct rte_eth_dev *dev, uint16_t rxq_id);

/**
 * Stop traffic on Rx queue.
 *
 * @param dev
 *   Pointer to Ethernet device structure.
 * @param txq_id
 *   RX queue index.
 */
int
nfb_eth_rx_queue_stop(struct rte_eth_dev *dev, uint16_t rxq_id);

/**
 * DPDK callback for RX.
 *
 * @param dpdk_rxq
 *   Generic pointer to RX queue structure.
 * @param[out] bufs
 *   Array to store received packets.
 * @param nb_pkts
 *   Maximum number of packets in array.
 *
 * @return
 *   Number of packets successfully received (<= nb_pkts).
 */
static __rte_always_inline uint16_t
nfb_eth_ndp_rx(void *queue,
        struct rte_mbuf **bufs,
        uint16_t nb_pkts)
{
        struct ndp_rx_queue *ndp = queue;
        uint8_t timestamping_enabled;
        uint16_t packet_size;
        uint64_t num_bytes = 0;
        uint16_t num_rx;
        unsigned int i;

        const uint16_t buf_size = ndp->buf_size;

        struct rte_mbuf *mbuf;
        struct ndp_packet packets[nb_pkts];

        struct rte_mbuf *mbufs[nb_pkts];

        if (unlikely(ndp->queue == NULL || nb_pkts == 0)) {
                RTE_LOG(ERR, PMD, "RX invalid arguments!\n");
                return 0;
        }

        timestamping_enabled = ndp->flags & NFB_TIMESTAMP_FLAG;

        /* returns either all or nothing */
        i = rte_pktmbuf_alloc_bulk(ndp->mb_pool, mbufs, nb_pkts);
        if (unlikely(i != 0))
                return 0;

        num_rx = ndp_rx_burst_get(ndp->queue, packets, nb_pkts);

        if (unlikely(num_rx != nb_pkts)) {
                for (i = num_rx; i < nb_pkts; i++)
                        rte_pktmbuf_free(mbufs[i]);
        }

        nb_pkts = num_rx;

        num_rx = 0;
        /*
         * Reads the given number of packets from NDP queue given
         * by queue and copies the packet data into a newly allocated mbuf
         * to return.
         */
        for (i = 0; i < nb_pkts; ++i) {
                mbuf = mbufs[i];

                /* get the space available for data in the mbuf */
                packet_size = packets[i].data_length;

                if (likely(packet_size <= buf_size)) {
                        /* NDP packet will fit in one mbuf, go ahead and copy */
                        rte_memcpy(rte_pktmbuf_mtod(mbuf, void *),
                                packets[i].data, packet_size);

                        mbuf->data_len = (uint16_t)packet_size;

                        mbuf->pkt_len = packet_size;
                        mbuf->port = ndp->in_port;
                        mbuf->ol_flags = 0;

                        if (timestamping_enabled) {
                                rte_mbuf_timestamp_t timestamp;

                                /* nanoseconds */
                                timestamp =
                                        rte_le_to_cpu_32(*((uint32_t *)
                                        (packets[i].header + 4)));
                                timestamp <<= 32;
                                /* seconds */
                                timestamp |=
                                        rte_le_to_cpu_32(*((uint32_t *)
                                        (packets[i].header + 8)));
                                *nfb_timestamp_dynfield(mbuf) = timestamp;
                                mbuf->ol_flags |= nfb_timestamp_rx_dynflag;
                        }

                        bufs[num_rx++] = mbuf;
                        num_bytes += packet_size;
                } else {
                        /*
                         * NDP packet will not fit in one mbuf,
                         * scattered mode is not enabled, drop packet
                         */
                        rte_pktmbuf_free(mbuf);
                }
        }

        ndp_rx_burst_put(ndp->queue);

        ndp->rx_pkts += num_rx;
        ndp->rx_bytes += num_bytes;
        return num_rx;
}

#endif /* _NFB_RX_H_ */