// SPDX-License-Identifier: GPL-2.0
/* Copyright(c) 1999 - 2018 Intel Corporation. */

#include "ixgbe.h"
#include "ixgbe_type.h"
#include "ixgbe_dcb.h"
#include "ixgbe_dcb_82598.h"
#include "ixgbe_dcb_82599.h"

/**
 * ixgbe_ieee_credits - This calculates the ieee traffic class
 * credits from the configured bandwidth percentages. Credits
 * are the smallest unit programmable into the underlying
 * hardware. The IEEE 802.1Qaz specification do not use bandwidth
 * groups so this is much simplified from the CEE case.
 * @bw: bandwidth index by traffic class
 * @refill: refill credits index by traffic class
 * @max: max credits by traffic class
 * @max_frame: maximum frame size
 */
static int ixgbe_ieee_credits(__u8 *bw, __u16 *refill,
                              __u16 *max, int max_frame)
{
        int min_percent = 100;
        int min_credit, multiplier;
        int i;

        min_credit = ((max_frame / 2) + DCB_CREDIT_QUANTUM - 1) /
                        DCB_CREDIT_QUANTUM;

        for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
                if (bw[i] < min_percent && bw[i])
                        min_percent = bw[i];
        }

        multiplier = (min_credit / min_percent) + 1;

        /* Find out the hw credits for each TC */
        for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
                int val = min(bw[i] * multiplier, MAX_CREDIT_REFILL);

                if (val < min_credit)
                        val = min_credit;
                refill[i] = val;

                max[i] = bw[i] ? (bw[i] * MAX_CREDIT)/100 : min_credit;
        }
        return 0;
}

/**
 * ixgbe_dcb_calculate_tc_credits - Calculates traffic class credits
 * @hw: pointer to hardware structure
 * @dcb_config: Struct containing DCB settings
 * @max_frame: Maximum frame size
 * @direction: Configuring either Tx or Rx
 *
 * This function calculates the credits allocated to each traffic class.
 * It should be called only after the rules are checked by
 * ixgbe_dcb_check_config().
 */
int ixgbe_dcb_calculate_tc_credits(struct ixgbe_hw *hw,
                                   struct ixgbe_dcb_config *dcb_config,
                                   int max_frame, u8 direction)
{
        struct tc_bw_alloc *p;
        int min_credit;
        int min_multiplier;
        int min_percent = 100;
        /* Initialization values default for Tx settings */
        u32 credit_refill       = 0;
        u32 credit_max          = 0;
        u16 link_percentage     = 0;
        u8  bw_percent          = 0;
        u8  i;

        if (!dcb_config)
                return DCB_ERR_CONFIG;

        min_credit = ((max_frame / 2) + DCB_CREDIT_QUANTUM - 1) /
                        DCB_CREDIT_QUANTUM;

        /* Find smallest link percentage */
        for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
                p = &dcb_config->tc_config[i].path[direction];
                bw_percent = dcb_config->bw_percentage[direction][p->bwg_id];
                link_percentage = p->bwg_percent;

                link_percentage = (link_percentage * bw_percent) / 100;

                if (link_percentage && link_percentage < min_percent)
                        min_percent = link_percentage;
        }

        /*
         * The ratio between traffic classes will control the bandwidth
         * percentages seen on the wire. To calculate this ratio we use
         * a multiplier. It is required that the refill credits must be
         * larger than the max frame size so here we find the smallest
         * multiplier that will allow all bandwidth percentages to be
         * greater than the max frame size.
         */
        min_multiplier = (min_credit / min_percent) + 1;

        /* Find out the link percentage for each TC first */
        for (i = 0; i < MAX_TRAFFIC_CLASS; i++) {
                p = &dcb_config->tc_config[i].path[direction];
                bw_percent = dcb_config->bw_percentage[direction][p->bwg_id];

                link_percentage = p->bwg_percent;
                /* Must be careful of integer division for very small nums */
                link_percentage = (link_percentage * bw_percent) / 100;
                if (p->bwg_percent > 0 && link_percentage == 0)
                        link_percentage = 1;

                /* Save link_percentage for reference */
                p->link_percent = (u8)link_percentage;

                /* Calculate credit refill ratio using multiplier */
                credit_refill = min(link_percentage * min_multiplier,
                                    MAX_CREDIT_REFILL);

                /* Refill at least minimum credit */
                if (credit_refill < min_credit)
                        credit_refill = min_credit;

                p->data_credits_refill = (u16)credit_refill;

                /* Calculate maximum credit for the TC */
                credit_max = (link_percentage * MAX_CREDIT) / 100;

                /*
                 * Adjustment based on rule checking, if the percentage
                 * of a TC is too small, the maximum credit may not be
                 * enough to send out a jumbo frame in data plane arbitration.
                 */
                if (credit_max < min_credit)
                        credit_max = min_credit;

                if (direction == DCB_TX_CONFIG) {
                        /*
                         * Adjustment based on rule checking, if the
                         * percentage of a TC is too small, the maximum
                         * credit may not be enough to send out a TSO
                         * packet in descriptor plane arbitration.
                         */
                        if ((hw->mac.type == ixgbe_mac_82598EB) &&
                            credit_max &&
                            (credit_max < MINIMUM_CREDIT_FOR_TSO))
                                credit_max = MINIMUM_CREDIT_FOR_TSO;

                        dcb_config->tc_config[i].desc_credits_max =
                                (u16)credit_max;
                }

                p->data_credits_max = (u16)credit_max;
        }

        return 0;
}

void ixgbe_dcb_unpack_pfc(struct ixgbe_dcb_config *cfg, u8 *pfc_en)
{
        struct tc_configuration *tc_config = &cfg->tc_config[0];
        int tc;

        for (*pfc_en = 0, tc = 0; tc < MAX_TRAFFIC_CLASS; tc++) {
                if (tc_config[tc].dcb_pfc != pfc_disabled)
                        *pfc_en |= BIT(tc);
        }
}

void ixgbe_dcb_unpack_refill(struct ixgbe_dcb_config *cfg, int direction,
                             u16 *refill)
{
        struct tc_configuration *tc_config = &cfg->tc_config[0];
        int tc;

        for (tc = 0; tc < MAX_TRAFFIC_CLASS; tc++)
                refill[tc] = tc_config[tc].path[direction].data_credits_refill;
}

void ixgbe_dcb_unpack_max(struct ixgbe_dcb_config *cfg, u16 *max)
{
        struct tc_configuration *tc_config = &cfg->tc_config[0];
        int tc;

        for (tc = 0; tc < MAX_TRAFFIC_CLASS; tc++)
                max[tc] = tc_config[tc].desc_credits_max;
}

void ixgbe_dcb_unpack_bwgid(struct ixgbe_dcb_config *cfg, int direction,
                            u8 *bwgid)
{
        struct tc_configuration *tc_config = &cfg->tc_config[0];
        int tc;

        for (tc = 0; tc < MAX_TRAFFIC_CLASS; tc++)
                bwgid[tc] = tc_config[tc].path[direction].bwg_id;
}

void ixgbe_dcb_unpack_prio(struct ixgbe_dcb_config *cfg, int direction,
                            u8 *ptype)
{
        struct tc_configuration *tc_config = &cfg->tc_config[0];
        int tc;

        for (tc = 0; tc < MAX_TRAFFIC_CLASS; tc++)
                ptype[tc] = tc_config[tc].path[direction].prio_type;
}

u8 ixgbe_dcb_get_tc_from_up(struct ixgbe_dcb_config *cfg, int direction, u8 up)
{
        struct tc_configuration *tc_config = &cfg->tc_config[0];
        u8 prio_mask = BIT(up);
        u8 tc = cfg->num_tcs.pg_tcs;

        /* If tc is 0 then DCB is likely not enabled or supported */
        if (!tc)
                return 0;

        /*
         * Test from maximum TC to 1 and report the first match we find.  If
         * we find no match we can assume that the TC is 0 since the TC must
         * be set for all user priorities
         */
        for (tc--; tc; tc--) {
                if (prio_mask & tc_config[tc].path[direction].up_to_tc_bitmap)
                        break;
        }

        return tc;
}

void ixgbe_dcb_unpack_map(struct ixgbe_dcb_config *cfg, int direction, u8 *map)
{
        u8 up;

        for (up = 0; up < MAX_USER_PRIORITY; up++)
                map[up] = ixgbe_dcb_get_tc_from_up(cfg, direction, up);
}

/**
 * ixgbe_dcb_hw_config - Config and enable DCB
 * @hw: pointer to hardware structure
 * @dcb_config: pointer to ixgbe_dcb_config structure
 *
 * Configure dcb settings and enable dcb mode.
 */
int ixgbe_dcb_hw_config(struct ixgbe_hw *hw,
                        struct ixgbe_dcb_config *dcb_config)
{
        u8 pfc_en;
        u8 ptype[MAX_TRAFFIC_CLASS];
        u8 bwgid[MAX_TRAFFIC_CLASS];
        u8 prio_tc[MAX_TRAFFIC_CLASS];
        u16 refill[MAX_TRAFFIC_CLASS];
        u16 max[MAX_TRAFFIC_CLASS];

        /* Unpack CEE standard containers */
        ixgbe_dcb_unpack_pfc(dcb_config, &pfc_en);
        ixgbe_dcb_unpack_refill(dcb_config, DCB_TX_CONFIG, refill);
        ixgbe_dcb_unpack_max(dcb_config, max);
        ixgbe_dcb_unpack_bwgid(dcb_config, DCB_TX_CONFIG, bwgid);
        ixgbe_dcb_unpack_prio(dcb_config, DCB_TX_CONFIG, ptype);
        ixgbe_dcb_unpack_map(dcb_config, DCB_TX_CONFIG, prio_tc);

        switch (hw->mac.type) {
        case ixgbe_mac_82598EB:
                return ixgbe_dcb_hw_config_82598(hw, pfc_en, refill, max,
                                                 bwgid, ptype);
        case ixgbe_mac_82599EB:
        case ixgbe_mac_X540:
        case ixgbe_mac_X550:
        case ixgbe_mac_X550EM_x:
        case ixgbe_mac_x550em_a:
                return ixgbe_dcb_hw_config_82599(hw, pfc_en, refill, max,
                                                 bwgid, ptype, prio_tc);
        default:
                break;
        }
        return 0;
}

/* Helper routines to abstract HW specifics from DCB netlink ops */
int ixgbe_dcb_hw_pfc_config(struct ixgbe_hw *hw, u8 pfc_en, u8 *prio_tc)
{
        switch (hw->mac.type) {
        case ixgbe_mac_82598EB:
                return ixgbe_dcb_config_pfc_82598(hw, pfc_en);
        case ixgbe_mac_82599EB:
        case ixgbe_mac_X540:
        case ixgbe_mac_X550:
        case ixgbe_mac_X550EM_x:
        case ixgbe_mac_x550em_a:
                return ixgbe_dcb_config_pfc_82599(hw, pfc_en, prio_tc);
        default:
                break;
        }
        return -EINVAL;
}

int ixgbe_dcb_hw_ets(struct ixgbe_hw *hw, struct ieee_ets *ets, int max_frame)
{
        __u16 refill[IEEE_8021QAZ_MAX_TCS], max[IEEE_8021QAZ_MAX_TCS];
        __u8 prio_type[IEEE_8021QAZ_MAX_TCS];
        int i;

        /* naively give each TC a bwg to map onto CEE hardware */
        __u8 bwg_id[IEEE_8021QAZ_MAX_TCS] = {0, 1, 2, 3, 4, 5, 6, 7};

        /* Map TSA onto CEE prio type */
        for (i = 0; i < IEEE_8021QAZ_MAX_TCS; i++) {
                switch (ets->tc_tsa[i]) {
                case IEEE_8021QAZ_TSA_STRICT:
                        prio_type[i] = 2;
                        break;
                case IEEE_8021QAZ_TSA_ETS:
                        prio_type[i] = 0;
                        break;
                default:
                        /* Hardware only supports priority strict or
                         * ETS transmission selection algorithms if
                         * we receive some other value from dcbnl
                         * throw an error
                         */
                        return -EINVAL;
                }
        }

        ixgbe_ieee_credits(ets->tc_tx_bw, refill, max, max_frame);
        return ixgbe_dcb_hw_ets_config(hw, refill, max,
                                       bwg_id, prio_type, ets->prio_tc);
}

int ixgbe_dcb_hw_ets_config(struct ixgbe_hw *hw,
                            u16 *refill, u16 *max, u8 *bwg_id,
                            u8 *prio_type, u8 *prio_tc)
{
        switch (hw->mac.type) {
        case ixgbe_mac_82598EB:
                ixgbe_dcb_config_rx_arbiter_82598(hw, refill, max,
                                                        prio_type);
                ixgbe_dcb_config_tx_desc_arbiter_82598(hw, refill, max,
                                                             bwg_id, prio_type);
                ixgbe_dcb_config_tx_data_arbiter_82598(hw, refill, max,
                                                             bwg_id, prio_type);
                break;
        case ixgbe_mac_82599EB:
        case ixgbe_mac_X540:
        case ixgbe_mac_X550:
        case ixgbe_mac_X550EM_x:
        case ixgbe_mac_x550em_a:
                ixgbe_dcb_config_rx_arbiter_82599(hw, refill, max,
                                                  bwg_id, prio_type, prio_tc);
                ixgbe_dcb_config_tx_desc_arbiter_82599(hw, refill, max,
                                                       bwg_id, prio_type);
                ixgbe_dcb_config_tx_data_arbiter_82599(hw, refill, max, bwg_id,
                                                       prio_type, prio_tc);
                break;
        default:
                break;
        }
        return 0;
}

static void ixgbe_dcb_read_rtrup2tc_82599(struct ixgbe_hw *hw, u8 *map)
{
        u32 reg, i;

        reg = IXGBE_READ_REG(hw, IXGBE_RTRUP2TC);
        for (i = 0; i < MAX_USER_PRIORITY; i++)
                map[i] = IXGBE_RTRUP2TC_UP_MASK &
                        (reg >> (i * IXGBE_RTRUP2TC_UP_SHIFT));
}

void ixgbe_dcb_read_rtrup2tc(struct ixgbe_hw *hw, u8 *map)
{
        switch (hw->mac.type) {
        case ixgbe_mac_82599EB:
        case ixgbe_mac_X540:
        case ixgbe_mac_X550:
        case ixgbe_mac_X550EM_x:
        case ixgbe_mac_x550em_a:
                ixgbe_dcb_read_rtrup2tc_82599(hw, map);
                break;
        default:
                break;
        }
}