/*
 * Copyright (c) 2011 Mellanox Technologies. All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     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.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 *
 */

#include <linux/dcbnl.h>
#include <linux/math64.h>

#include "mlx4_en.h"

static int mlx4_en_dcbnl_ieee_getets(struct net_device *dev,
                                   struct ieee_ets *ets)
{
        struct mlx4_en_priv *priv = netdev_priv(dev);
        struct ieee_ets *my_ets = &priv->ets;

        /* No IEEE PFC settings available */
        if (!my_ets)
                return -EINVAL;

        ets->ets_cap = IEEE_8021QAZ_MAX_TCS;
        ets->cbs = my_ets->cbs;
        memcpy(ets->tc_tx_bw, my_ets->tc_tx_bw, sizeof(ets->tc_tx_bw));
        memcpy(ets->tc_tsa, my_ets->tc_tsa, sizeof(ets->tc_tsa));
        memcpy(ets->prio_tc, my_ets->prio_tc, sizeof(ets->prio_tc));

        return 0;
}

static int mlx4_en_ets_validate(struct mlx4_en_priv *priv, struct ieee_ets *ets)
{
        int i;
        int total_ets_bw = 0;
        int has_ets_tc = 0;

        for (i = 0; i < IEEE_8021QAZ_MAX_TCS; i++) {
                if (ets->prio_tc[i] > MLX4_EN_NUM_UP) {
                        en_err(priv, "Bad priority in UP <=> TC mapping. TC: %d, UP: %d\n",
                                        i, ets->prio_tc[i]);
                        return -EINVAL;
                }

                switch (ets->tc_tsa[i]) {
                case IEEE_8021QAZ_TSA_STRICT:
                        break;
                case IEEE_8021QAZ_TSA_ETS:
                        has_ets_tc = 1;
                        total_ets_bw += ets->tc_tx_bw[i];
                        break;
                default:
                        en_err(priv, "TC[%d]: Not supported TSA: %d\n",
                                        i, ets->tc_tsa[i]);
                        return -ENOTSUPP;
                }
        }

        if (has_ets_tc && total_ets_bw != MLX4_EN_BW_MAX) {
                en_err(priv, "Bad ETS BW sum: %d. Should be exactly 100%%\n",
                                total_ets_bw);
                return -EINVAL;
        }

        return 0;
}

static int mlx4_en_config_port_scheduler(struct mlx4_en_priv *priv,
                struct ieee_ets *ets, u16 *ratelimit)
{
        struct mlx4_en_dev *mdev = priv->mdev;
        int num_strict = 0;
        int i;
        __u8 tc_tx_bw[IEEE_8021QAZ_MAX_TCS] = { 0 };
        __u8 pg[IEEE_8021QAZ_MAX_TCS] = { 0 };

        ets = ets ?: &priv->ets;
        ratelimit = ratelimit ?: priv->maxrate;

        /* higher TC means higher priority => lower pg */
        for (i = IEEE_8021QAZ_MAX_TCS - 1; i >= 0; i--) {
                switch (ets->tc_tsa[i]) {
                case IEEE_8021QAZ_TSA_STRICT:
                        pg[i] = num_strict++;
                        tc_tx_bw[i] = MLX4_EN_BW_MAX;
                        break;
                case IEEE_8021QAZ_TSA_ETS:
                        pg[i] = MLX4_EN_TC_ETS;
                        tc_tx_bw[i] = ets->tc_tx_bw[i] ?: MLX4_EN_BW_MIN;
                        break;
                }
        }

        return mlx4_SET_PORT_SCHEDULER(mdev->dev, priv->port, tc_tx_bw, pg,
                        ratelimit);
}

static int
mlx4_en_dcbnl_ieee_setets(struct net_device *dev, struct ieee_ets *ets)
{
        struct mlx4_en_priv *priv = netdev_priv(dev);
        struct mlx4_en_dev *mdev = priv->mdev;
        int err;

        err = mlx4_en_ets_validate(priv, ets);
        if (err)
                return err;

        err = mlx4_SET_PORT_PRIO2TC(mdev->dev, priv->port, ets->prio_tc);
        if (err)
                return err;

        err = mlx4_en_config_port_scheduler(priv, ets, NULL);
        if (err)
                return err;

        memcpy(&priv->ets, ets, sizeof(priv->ets));

        return 0;
}

static int mlx4_en_dcbnl_ieee_getpfc(struct net_device *dev,
                struct ieee_pfc *pfc)
{
        struct mlx4_en_priv *priv = netdev_priv(dev);

        pfc->pfc_cap = IEEE_8021QAZ_MAX_TCS;
        pfc->pfc_en = priv->prof->tx_ppp;

        return 0;
}

static int mlx4_en_dcbnl_ieee_setpfc(struct net_device *dev,
                struct ieee_pfc *pfc)
{
        struct mlx4_en_priv *priv = netdev_priv(dev);
        struct mlx4_en_port_profile *prof = priv->prof;
        struct mlx4_en_dev *mdev = priv->mdev;
        int err;

        en_dbg(DRV, priv, "cap: 0x%x en: 0x%x mbc: 0x%x delay: %d\n",
                        pfc->pfc_cap,
                        pfc->pfc_en,
                        pfc->mbc,
                        pfc->delay);

        prof->rx_pause = !pfc->pfc_en;
        prof->tx_pause = !pfc->pfc_en;
        prof->rx_ppp = pfc->pfc_en;
        prof->tx_ppp = pfc->pfc_en;

        err = mlx4_SET_PORT_general(mdev->dev, priv->port,
                                    priv->rx_skb_size + ETH_FCS_LEN,
                                    prof->tx_pause,
                                    prof->tx_ppp,
                                    prof->rx_pause,
                                    prof->rx_ppp);
        if (err)
                en_err(priv, "Failed setting pause params\n");

        return err;
}

static u8 mlx4_en_dcbnl_getdcbx(struct net_device *dev)
{
        return DCB_CAP_DCBX_HOST | DCB_CAP_DCBX_VER_IEEE;
}

static u8 mlx4_en_dcbnl_setdcbx(struct net_device *dev, u8 mode)
{
        if ((mode & DCB_CAP_DCBX_LLD_MANAGED) ||
            (mode & DCB_CAP_DCBX_VER_CEE) ||
            !(mode & DCB_CAP_DCBX_VER_IEEE) ||
            !(mode & DCB_CAP_DCBX_HOST))
                return 1;

        return 0;
}

#define MLX4_RATELIMIT_UNITS_IN_KB 100000 /* rate-limit HW unit in Kbps */
static int mlx4_en_dcbnl_ieee_getmaxrate(struct net_device *dev,
                                   struct ieee_maxrate *maxrate)
{
        struct mlx4_en_priv *priv = netdev_priv(dev);
        int i;

        for (i = 0; i < IEEE_8021QAZ_MAX_TCS; i++)
                maxrate->tc_maxrate[i] =
                        priv->maxrate[i] * MLX4_RATELIMIT_UNITS_IN_KB;

        return 0;
}

static int mlx4_en_dcbnl_ieee_setmaxrate(struct net_device *dev,
                struct ieee_maxrate *maxrate)
{
        struct mlx4_en_priv *priv = netdev_priv(dev);
        u16 tmp[IEEE_8021QAZ_MAX_TCS];
        int i, err;

        for (i = 0; i < IEEE_8021QAZ_MAX_TCS; i++) {
                /* Convert from Kbps into HW units, rounding result up.
                 * Setting to 0, means unlimited BW.
                 */
                tmp[i] = div_u64(maxrate->tc_maxrate[i] +
                                 MLX4_RATELIMIT_UNITS_IN_KB - 1,
                                 MLX4_RATELIMIT_UNITS_IN_KB);
        }

        err = mlx4_en_config_port_scheduler(priv, NULL, tmp);
        if (err)
                return err;

        memcpy(priv->maxrate, tmp, sizeof(priv->maxrate));

        return 0;
}

const struct dcbnl_rtnl_ops mlx4_en_dcbnl_ops = {
        .ieee_getets    = mlx4_en_dcbnl_ieee_getets,
        .ieee_setets    = mlx4_en_dcbnl_ieee_setets,
        .ieee_getmaxrate = mlx4_en_dcbnl_ieee_getmaxrate,
        .ieee_setmaxrate = mlx4_en_dcbnl_ieee_setmaxrate,
        .ieee_getpfc    = mlx4_en_dcbnl_ieee_getpfc,
        .ieee_setpfc    = mlx4_en_dcbnl_ieee_setpfc,

        .getdcbx        = mlx4_en_dcbnl_getdcbx,
        .setdcbx        = mlx4_en_dcbnl_setdcbx,
};

const struct dcbnl_rtnl_ops mlx4_en_dcbnl_pfc_ops = {
        .ieee_getpfc    = mlx4_en_dcbnl_ieee_getpfc,
        .ieee_setpfc    = mlx4_en_dcbnl_ieee_setpfc,

        .getdcbx        = mlx4_en_dcbnl_getdcbx,
        .setdcbx        = mlx4_en_dcbnl_setdcbx,
};