/*-
 * SPDX-License-Identifier: BSD-2-Clause
 *
 * Copyright (c) 2007-2008 Sam Leffler, Errno Consulting
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
 */

#ifndef _NET80211_IEEE80211_PHY_H_
#define _NET80211_IEEE80211_PHY_H_

#ifdef _KERNEL
/*
 * IEEE 802.11 PHY-related definitions.
 */

/*
 * Contention window (slots).
 */
#define IEEE80211_CW_MAX        1023    /* aCWmax */
#define IEEE80211_CW_MIN_0      31      /* DS/CCK aCWmin, ERP aCWmin(0) */
#define IEEE80211_CW_MIN_1      15      /* OFDM aCWmin, ERP aCWmin(1) */

/*
 * SIFS (microseconds).
 */
#define IEEE80211_DUR_SIFS      10      /* DS/CCK/ERP SIFS */
#define IEEE80211_DUR_OFDM_SIFS 16      /* OFDM SIFS */

/*
 * Slot time (microseconds).
 */
#define IEEE80211_DUR_SLOT      20      /* DS/CCK slottime, ERP long slottime */
#define IEEE80211_DUR_SHSLOT    9       /* ERP short slottime */
#define IEEE80211_DUR_OFDM_SLOT 9       /* OFDM slottime */

/*
 * For drivers that don't implement per-VAP slot time
 * (ie, they rely on net80211 figuring out the union
 * between VAPs to program a single radio) - return
 * the current radio configured slot time.
 */
#define IEEE80211_GET_SLOTTIME(ic) \
        ((ic->ic_flags & IEEE80211_F_SHSLOT) ? \
            IEEE80211_DUR_SHSLOT : IEEE80211_DUR_SLOT)

/*
 * For drivers that implement per-VAP slot time; look
 * at the per-VAP flags to determine whether this VAP
 * is in short or long slot time.
 */
#define IEEE80211_VAP_GET_SLOTTIME(vap) \
        ((vap->iv_flags & IEEE80211_F_SHSLOT) ? \
            IEEE80211_DUR_SHSLOT : IEEE80211_DUR_SLOT)

/*
 * DIFS (microseconds).
 */
#define IEEE80211_DUR_DIFS(sifs, slot)  ((sifs) + 2 * (slot))

struct ieee80211_channel;

#define IEEE80211_RATE_TABLE_SIZE       128

struct ieee80211_rate_table {
        int             rateCount;              /* NB: for proper padding */
        uint8_t         rateCodeToIndex[256];   /* back mapping */
        struct {
                uint8_t         phy;            /* CCK/OFDM/TURBO */
                uint32_t        rateKbps;       /* transfer rate in kbs */
                uint8_t         shortPreamble;  /* mask for enabling short
                                                 * preamble in CCK rate code */
                uint8_t         dot11Rate;      /* value for supported rates
                                                 * info element of MLME */
                uint8_t         ctlRateIndex;   /* index of next lower basic
                                                 * rate; used for dur. calcs */
                uint16_t        lpAckDuration;  /* long preamble ACK dur. */
                uint16_t        spAckDuration;  /* short preamble ACK dur. */
        } info[IEEE80211_RATE_TABLE_SIZE];
};

const struct ieee80211_rate_table *ieee80211_get_ratetable(
                        struct ieee80211_channel *);

static __inline__ uint8_t
ieee80211_ack_rate(const struct ieee80211_rate_table *rt, uint8_t rate)
{
        /*
         * XXX Assert this is for a legacy rate; not for an MCS rate.
         * If the caller wishes to use it for a basic rate, they should
         * clear the high bit first.
         */
        KASSERT(! (rate & 0x80), ("rate %d is basic/mcs?", rate));

        uint8_t cix = rt->info[rt->rateCodeToIndex[rate & IEEE80211_RATE_VAL]].ctlRateIndex;
        KASSERT(cix != (uint8_t)-1, ("rate %d has no info", rate));
        return rt->info[cix].dot11Rate;
}

static __inline__ uint8_t
ieee80211_ctl_rate(const struct ieee80211_rate_table *rt, uint8_t rate)
{
        /*
         * XXX Assert this is for a legacy rate; not for an MCS rate.
         * If the caller wishes to use it for a basic rate, they should
         * clear the high bit first.
         */
        KASSERT(! (rate & 0x80), ("rate %d is basic/mcs?", rate));

        uint8_t cix = rt->info[rt->rateCodeToIndex[rate & IEEE80211_RATE_VAL]].ctlRateIndex;
        KASSERT(cix != (uint8_t)-1, ("rate %d has no info", rate));
        return rt->info[cix].dot11Rate;
}

static __inline__ enum ieee80211_phytype
ieee80211_rate2phytype(const struct ieee80211_rate_table *rt, uint8_t rate)
{
        /*
         * XXX Assert this is for a legacy rate; not for an MCS rate.
         * If the caller wishes to use it for a basic rate, they should
         * clear the high bit first.
         */
        KASSERT(! (rate & 0x80), ("rate %d is basic/mcs?", rate));

        uint8_t rix = rt->rateCodeToIndex[rate & IEEE80211_RATE_VAL];
        KASSERT(rix != (uint8_t)-1, ("rate %d has no info", rate));
        return rt->info[rix].phy;
}

static __inline__ int
ieee80211_isratevalid(const struct ieee80211_rate_table *rt, uint8_t rate)
{
        /*
         * XXX Assert this is for a legacy rate; not for an MCS rate.
         * If the caller wishes to use it for a basic rate, they should
         * clear the high bit first.
         */
        KASSERT(! (rate & 0x80), ("rate %d is basic/mcs?", rate));

        return rt->rateCodeToIndex[rate] != (uint8_t)-1;
}

/*
 * Calculate ACK field for
 * o  non-fragment data frames
 * o  management frames
 * sent using rate, phy and short preamble setting.
 */
static __inline__ uint16_t
ieee80211_ack_duration(const struct ieee80211_rate_table *rt,
    uint8_t rate, int isShortPreamble)
{
        uint8_t rix = rt->rateCodeToIndex[rate];

        KASSERT(rix != (uint8_t)-1, ("rate %d has no info", rate));
        if (isShortPreamble) {
                KASSERT(rt->info[rix].spAckDuration != 0,
                        ("shpreamble ack dur is not computed!\n"));
                return rt->info[rix].spAckDuration;
        } else {
                KASSERT(rt->info[rix].lpAckDuration != 0,
                        ("lgpreamble ack dur is not computed!\n"));
                return rt->info[rix].lpAckDuration;
        }
}

static __inline__ uint8_t
ieee80211_legacy_rate_lookup(const struct ieee80211_rate_table *rt,
    uint8_t rate)
{

        return (rt->rateCodeToIndex[rate & IEEE80211_RATE_VAL]);
}

/*
 * Compute the time to transmit a frame of length frameLen bytes
 * using the specified 802.11 rate code, phy, and short preamble
 * setting.
 *
 * NB: SIFS is included.
 */
uint16_t        ieee80211_compute_duration(const struct ieee80211_rate_table *,
                        uint32_t frameLen, uint16_t rate, int isShortPreamble);
/*
 * Convert PLCP signal/rate field to 802.11 rate code (.5Mbits/s)
 */
uint8_t         ieee80211_plcp2rate(uint8_t, enum ieee80211_phytype);
/*
 * Convert 802.11 rate code to PLCP signal.
 */
uint8_t         ieee80211_rate2plcp(int, enum ieee80211_phytype);

/*
 * 802.11n rate manipulation.
 */

#define IEEE80211_HT_RC_2_MCS(_rc)      ((_rc) & 0x1f)
#define IEEE80211_HT_RC_2_STREAMS(_rc)  ((((_rc) & 0x78) >> 3) + 1)
#define IEEE80211_IS_HT_RATE(_rc)               ( (_rc) & IEEE80211_RATE_MCS)

uint32_t        ieee80211_compute_duration_ht(uint32_t frameLen,
                        uint16_t rate, int streams, int isht40,
                        int isShortGI);

enum net80211_sta_rx_bw;

uint16_t        ieee80211_phy_vht_get_mcs_mask(enum net80211_sta_rx_bw,
                    uint8_t);
bool            ieee80211_phy_vht_validate_mcs(enum net80211_sta_rx_bw,
                    uint8_t, uint8_t);
uint32_t        ieee80211_phy_vht_get_mcs_kbit(enum net80211_sta_rx_bw,
                    uint8_t, uint8_t, bool);

#endif  /* _KERNEL */
#endif  /* !_NET80211_IEEE80211_PHY_H_ */