// SPDX-License-Identifier: GPL-2.0-or-later
/*

  Broadcom B43legacy wireless driver

  Transmission (TX/RX) related functions.

  Copyright (C) 2005 Martin Langer <martin-langer@gmx.de>
  Copyright (C) 2005 Stefano Brivio <stefano.brivio@polimi.it>
  Copyright (C) 2005, 2006 Michael Buesch <m@bues.ch>
  Copyright (C) 2005 Danny van Dyk <kugelfang@gentoo.org>
  Copyright (C) 2005 Andreas Jaggi <andreas.jaggi@waterwave.ch>
  Copyright (C) 2007 Larry Finger <Larry.Finger@lwfinger.net>


*/

#include <net/dst.h>

#include "xmit.h"
#include "phy.h"
#include "dma.h"
#include "pio.h"


/* Extract the bitrate out of a CCK PLCP header. */
static u8 b43legacy_plcp_get_bitrate_idx_cck(struct b43legacy_plcp_hdr6 *plcp)
{
        switch (plcp->raw[0]) {
        case 0x0A:
                return 0;
        case 0x14:
                return 1;
        case 0x37:
                return 2;
        case 0x6E:
                return 3;
        }
        B43legacy_BUG_ON(1);
        return -1;
}

/* Extract the bitrate out of an OFDM PLCP header. */
static u8 b43legacy_plcp_get_bitrate_idx_ofdm(struct b43legacy_plcp_hdr6 *plcp,
                                              bool aphy)
{
        int base = aphy ? 0 : 4;

        switch (plcp->raw[0] & 0xF) {
        case 0xB:
                return base + 0;
        case 0xF:
                return base + 1;
        case 0xA:
                return base + 2;
        case 0xE:
                return base + 3;
        case 0x9:
                return base + 4;
        case 0xD:
                return base + 5;
        case 0x8:
                return base + 6;
        case 0xC:
                return base + 7;
        }
        B43legacy_BUG_ON(1);
        return -1;
}

u8 b43legacy_plcp_get_ratecode_cck(const u8 bitrate)
{
        switch (bitrate) {
        case B43legacy_CCK_RATE_1MB:
                return 0x0A;
        case B43legacy_CCK_RATE_2MB:
                return 0x14;
        case B43legacy_CCK_RATE_5MB:
                return 0x37;
        case B43legacy_CCK_RATE_11MB:
                return 0x6E;
        }
        B43legacy_BUG_ON(1);
        return 0;
}

u8 b43legacy_plcp_get_ratecode_ofdm(const u8 bitrate)
{
        switch (bitrate) {
        case B43legacy_OFDM_RATE_6MB:
                return 0xB;
        case B43legacy_OFDM_RATE_9MB:
                return 0xF;
        case B43legacy_OFDM_RATE_12MB:
                return 0xA;
        case B43legacy_OFDM_RATE_18MB:
                return 0xE;
        case B43legacy_OFDM_RATE_24MB:
                return 0x9;
        case B43legacy_OFDM_RATE_36MB:
                return 0xD;
        case B43legacy_OFDM_RATE_48MB:
                return 0x8;
        case B43legacy_OFDM_RATE_54MB:
                return 0xC;
        }
        B43legacy_BUG_ON(1);
        return 0;
}

void b43legacy_generate_plcp_hdr(struct b43legacy_plcp_hdr4 *plcp,
                                 const u16 octets, const u8 bitrate)
{
        __le32 *data = &(plcp->data);
        __u8 *raw = plcp->raw;

        if (b43legacy_is_ofdm_rate(bitrate)) {
                u16 d;

                d = b43legacy_plcp_get_ratecode_ofdm(bitrate);
                B43legacy_WARN_ON(octets & 0xF000);
                d |= (octets << 5);
                *data = cpu_to_le32(d);
        } else {
                u32 plen;

                plen = octets * 16 / bitrate;
                if ((octets * 16 % bitrate) > 0) {
                        plen++;
                        if ((bitrate == B43legacy_CCK_RATE_11MB)
                            && ((octets * 8 % 11) < 4))
                                raw[1] = 0x84;
                        else
                                raw[1] = 0x04;
                } else
                        raw[1] = 0x04;
                *data |= cpu_to_le32(plen << 16);
                raw[0] = b43legacy_plcp_get_ratecode_cck(bitrate);
        }
}

static u8 b43legacy_calc_fallback_rate(u8 bitrate)
{
        switch (bitrate) {
        case B43legacy_CCK_RATE_1MB:
                return B43legacy_CCK_RATE_1MB;
        case B43legacy_CCK_RATE_2MB:
                return B43legacy_CCK_RATE_1MB;
        case B43legacy_CCK_RATE_5MB:
                return B43legacy_CCK_RATE_2MB;
        case B43legacy_CCK_RATE_11MB:
                return B43legacy_CCK_RATE_5MB;
        case B43legacy_OFDM_RATE_6MB:
                return B43legacy_CCK_RATE_5MB;
        case B43legacy_OFDM_RATE_9MB:
                return B43legacy_OFDM_RATE_6MB;
        case B43legacy_OFDM_RATE_12MB:
                return B43legacy_OFDM_RATE_9MB;
        case B43legacy_OFDM_RATE_18MB:
                return B43legacy_OFDM_RATE_12MB;
        case B43legacy_OFDM_RATE_24MB:
                return B43legacy_OFDM_RATE_18MB;
        case B43legacy_OFDM_RATE_36MB:
                return B43legacy_OFDM_RATE_24MB;
        case B43legacy_OFDM_RATE_48MB:
                return B43legacy_OFDM_RATE_36MB;
        case B43legacy_OFDM_RATE_54MB:
                return B43legacy_OFDM_RATE_48MB;
        }
        B43legacy_BUG_ON(1);
        return 0;
}

static int generate_txhdr_fw3(struct b43legacy_wldev *dev,
                               struct b43legacy_txhdr_fw3 *txhdr,
                               const unsigned char *fragment_data,
                               unsigned int fragment_len,
                               struct ieee80211_tx_info *info,
                               u16 cookie)
{
        const struct ieee80211_hdr *wlhdr;
        int use_encryption = !!info->control.hw_key;
        u8 rate;
        struct ieee80211_rate *rate_fb;
        int rate_ofdm;
        int rate_fb_ofdm;
        unsigned int plcp_fragment_len;
        u32 mac_ctl = 0;
        u16 phy_ctl = 0;
        struct ieee80211_rate *tx_rate;
        struct ieee80211_tx_rate *rates;

        wlhdr = (const struct ieee80211_hdr *)fragment_data;

        memset(txhdr, 0, sizeof(*txhdr));

        tx_rate = ieee80211_get_tx_rate(dev->wl->hw, info);

        rate = tx_rate->hw_value;
        rate_ofdm = b43legacy_is_ofdm_rate(rate);
        rate_fb = ieee80211_get_alt_retry_rate(dev->wl->hw, info, 0) ? : tx_rate;
        rate_fb_ofdm = b43legacy_is_ofdm_rate(rate_fb->hw_value);

        txhdr->mac_frame_ctl = wlhdr->frame_control;
        memcpy(txhdr->tx_receiver, wlhdr->addr1, ETH_ALEN);

        /* Calculate duration for fallback rate */
        if ((rate_fb->hw_value == rate) ||
            (wlhdr->duration_id & cpu_to_le16(0x8000)) ||
            (wlhdr->duration_id == cpu_to_le16(0))) {
                /* If the fallback rate equals the normal rate or the
                 * dur_id field contains an AID, CFP magic or 0,
                 * use the original dur_id field. */
                txhdr->dur_fb = wlhdr->duration_id;
        } else {
                txhdr->dur_fb = ieee80211_generic_frame_duration(dev->wl->hw,
                                                         info->control.vif,
                                                         info->band,
                                                         fragment_len,
                                                         rate_fb);
        }

        plcp_fragment_len = fragment_len + FCS_LEN;
        if (use_encryption) {
                u8 key_idx = info->control.hw_key->hw_key_idx;
                struct b43legacy_key *key;
                int wlhdr_len;
                size_t iv_len;

                B43legacy_WARN_ON(key_idx >= dev->max_nr_keys);
                key = &(dev->key[key_idx]);

                if (key->enabled) {
                        /* Hardware appends ICV. */
                        plcp_fragment_len += info->control.hw_key->icv_len;

                        key_idx = b43legacy_kidx_to_fw(dev, key_idx);
                        mac_ctl |= (key_idx << B43legacy_TX4_MAC_KEYIDX_SHIFT) &
                                   B43legacy_TX4_MAC_KEYIDX;
                        mac_ctl |= (key->algorithm <<
                                   B43legacy_TX4_MAC_KEYALG_SHIFT) &
                                   B43legacy_TX4_MAC_KEYALG;
                        wlhdr_len = ieee80211_hdrlen(wlhdr->frame_control);
                        iv_len = min_t(size_t, info->control.hw_key->iv_len,
                                     ARRAY_SIZE(txhdr->iv));
                        memcpy(txhdr->iv, ((u8 *)wlhdr) + wlhdr_len, iv_len);
                } else {
                        /* This key is invalid. This might only happen
                         * in a short timeframe after machine resume before
                         * we were able to reconfigure keys.
                         * Drop this packet completely. Do not transmit it
                         * unencrypted to avoid leaking information. */
                        return -ENOKEY;
                }
        }
        b43legacy_generate_plcp_hdr((struct b43legacy_plcp_hdr4 *)
                                    (&txhdr->plcp), plcp_fragment_len,
                                    rate);
        b43legacy_generate_plcp_hdr(&txhdr->plcp_fb, plcp_fragment_len,
                                    rate_fb->hw_value);

        /* PHY TX Control word */
        if (rate_ofdm)
                phy_ctl |= B43legacy_TX4_PHY_ENC_OFDM;
        if (info->control.rates[0].flags & IEEE80211_TX_RC_USE_SHORT_PREAMBLE)
                phy_ctl |= B43legacy_TX4_PHY_SHORTPRMBL;
        phy_ctl |= B43legacy_TX4_PHY_ANTLAST;

        /* MAC control */
        rates = info->control.rates;
        if (!(info->flags & IEEE80211_TX_CTL_NO_ACK))
                mac_ctl |= B43legacy_TX4_MAC_ACK;
        if (info->flags & IEEE80211_TX_CTL_ASSIGN_SEQ)
                mac_ctl |= B43legacy_TX4_MAC_HWSEQ;
        if (info->flags & IEEE80211_TX_CTL_FIRST_FRAGMENT)
                mac_ctl |= B43legacy_TX4_MAC_STMSDU;
        if (rate_fb_ofdm)
                mac_ctl |= B43legacy_TX4_MAC_FALLBACKOFDM;

        /* Overwrite rates[0].count to make the retry calculation
         * in the tx status easier. need the actual retry limit to
         * detect whether the fallback rate was used.
         */
        if ((rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS) ||
            (rates[0].count <= dev->wl->hw->conf.long_frame_max_tx_count)) {
                rates[0].count = dev->wl->hw->conf.long_frame_max_tx_count;
                mac_ctl |= B43legacy_TX4_MAC_LONGFRAME;
        } else {
                rates[0].count = dev->wl->hw->conf.short_frame_max_tx_count;
        }

        /* Generate the RTS or CTS-to-self frame */
        if ((rates[0].flags & IEEE80211_TX_RC_USE_RTS_CTS) ||
            (rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT)) {
                unsigned int len;
                struct ieee80211_hdr *hdr;
                int rts_rate;
                int rts_rate_fb;
                int rts_rate_fb_ofdm;

                rts_rate = ieee80211_get_rts_cts_rate(dev->wl->hw, info)->hw_value;
                rts_rate_fb = b43legacy_calc_fallback_rate(rts_rate);
                rts_rate_fb_ofdm = b43legacy_is_ofdm_rate(rts_rate_fb);
                if (rts_rate_fb_ofdm)
                        mac_ctl |= B43legacy_TX4_MAC_CTSFALLBACKOFDM;

                if (rates[0].flags & IEEE80211_TX_RC_USE_CTS_PROTECT) {
                        ieee80211_ctstoself_get(dev->wl->hw,
                                                info->control.vif,
                                                fragment_data,
                                                fragment_len, info,
                                                (struct ieee80211_cts *)
                                                (txhdr->rts_frame));
                        mac_ctl |= B43legacy_TX4_MAC_SENDCTS;
                        len = sizeof(struct ieee80211_cts);
                } else {
                        ieee80211_rts_get(dev->wl->hw,
                                          info->control.vif,
                                          fragment_data, fragment_len, info,
                                          (struct ieee80211_rts *)
                                          (txhdr->rts_frame));
                        mac_ctl |= B43legacy_TX4_MAC_SENDRTS;
                        len = sizeof(struct ieee80211_rts);
                }
                len += FCS_LEN;
                b43legacy_generate_plcp_hdr((struct b43legacy_plcp_hdr4 *)
                                            (&txhdr->rts_plcp),
                                            len, rts_rate);
                b43legacy_generate_plcp_hdr(&txhdr->rts_plcp_fb,
                                            len, rts_rate_fb);
                hdr = (struct ieee80211_hdr *)(&txhdr->rts_frame);
                txhdr->rts_dur_fb = hdr->duration_id;
        }

        /* Magic cookie */
        txhdr->cookie = cpu_to_le16(cookie);

        /* Apply the bitfields */
        txhdr->mac_ctl = cpu_to_le32(mac_ctl);
        txhdr->phy_ctl = cpu_to_le16(phy_ctl);

        return 0;
}

int b43legacy_generate_txhdr(struct b43legacy_wldev *dev,
                              u8 *txhdr,
                              const unsigned char *fragment_data,
                              unsigned int fragment_len,
                              struct ieee80211_tx_info *info,
                              u16 cookie)
{
        return generate_txhdr_fw3(dev, (struct b43legacy_txhdr_fw3 *)txhdr,
                           fragment_data, fragment_len,
                           info, cookie);
}

static s8 b43legacy_rssi_postprocess(struct b43legacy_wldev *dev,
                                     u8 in_rssi, int ofdm,
                                     int adjust_2053, int adjust_2050)
{
        struct b43legacy_phy *phy = &dev->phy;
        s32 tmp;

        switch (phy->radio_ver) {
        case 0x2050:
                if (ofdm) {
                        tmp = in_rssi;
                        if (tmp > 127)
                                tmp -= 256;
                        tmp *= 73;
                        tmp /= 64;
                        if (adjust_2050)
                                tmp += 25;
                        else
                                tmp -= 3;
                } else {
                        if (dev->dev->bus->sprom.boardflags_lo
                            & B43legacy_BFL_RSSI) {
                                if (in_rssi > 63)
                                        in_rssi = 63;
                                tmp = phy->nrssi_lt[in_rssi];
                                tmp = 31 - tmp;
                                tmp *= -131;
                                tmp /= 128;
                                tmp -= 57;
                        } else {
                                tmp = in_rssi;
                                tmp = 31 - tmp;
                                tmp *= -149;
                                tmp /= 128;
                                tmp -= 68;
                        }
                        if (phy->type == B43legacy_PHYTYPE_G &&
                            adjust_2050)
                                tmp += 25;
                }
                break;
        case 0x2060:
                if (in_rssi > 127)
                        tmp = in_rssi - 256;
                else
                        tmp = in_rssi;
                break;
        default:
                tmp = in_rssi;
                tmp -= 11;
                tmp *= 103;
                tmp /= 64;
                if (adjust_2053)
                        tmp -= 109;
                else
                        tmp -= 83;
        }

        return (s8)tmp;
}

void b43legacy_rx(struct b43legacy_wldev *dev,
                  struct sk_buff *skb,
                  const void *_rxhdr)
{
        struct ieee80211_rx_status status;
        struct b43legacy_plcp_hdr6 *plcp;
        struct ieee80211_hdr *wlhdr;
        const struct b43legacy_rxhdr_fw3 *rxhdr = _rxhdr;
        __le16 fctl;
        u16 phystat0;
        u16 phystat3;
        u16 chanstat;
        u16 mactime;
        u32 macstat;
        u16 chanid;
        u8 jssi;
        int padding;

        memset(&status, 0, sizeof(status));

        /* Get metadata about the frame from the header. */
        phystat0 = le16_to_cpu(rxhdr->phy_status0);
        phystat3 = le16_to_cpu(rxhdr->phy_status3);
        jssi = rxhdr->jssi;
        macstat = le16_to_cpu(rxhdr->mac_status);
        mactime = le16_to_cpu(rxhdr->mac_time);
        chanstat = le16_to_cpu(rxhdr->channel);

        if (macstat & B43legacy_RX_MAC_FCSERR)
                dev->wl->ieee_stats.dot11FCSErrorCount++;

        /* Skip PLCP and padding */
        padding = (macstat & B43legacy_RX_MAC_PADDING) ? 2 : 0;
        if (unlikely(skb->len < (sizeof(struct b43legacy_plcp_hdr6) +
            padding))) {
                b43legacydbg(dev->wl, "RX: Packet size underrun (1)\n");
                goto drop;
        }
        plcp = (struct b43legacy_plcp_hdr6 *)(skb->data + padding);
        skb_pull(skb, sizeof(struct b43legacy_plcp_hdr6) + padding);
        /* The skb contains the Wireless Header + payload data now */
        if (unlikely(skb->len < (2+2+6/*minimum hdr*/ + FCS_LEN))) {
                b43legacydbg(dev->wl, "RX: Packet size underrun (2)\n");
                goto drop;
        }
        wlhdr = (struct ieee80211_hdr *)(skb->data);
        fctl = wlhdr->frame_control;

        if ((macstat & B43legacy_RX_MAC_DEC) &&
            !(macstat & B43legacy_RX_MAC_DECERR)) {
                unsigned int keyidx;
                int wlhdr_len;
                int iv_len;
                int icv_len;

                keyidx = ((macstat & B43legacy_RX_MAC_KEYIDX)
                          >> B43legacy_RX_MAC_KEYIDX_SHIFT);
                /* We must adjust the key index here. We want the "physical"
                 * key index, but the ucode passed it slightly different.
                 */
                keyidx = b43legacy_kidx_to_raw(dev, keyidx);
                B43legacy_WARN_ON(keyidx >= dev->max_nr_keys);

                if (dev->key[keyidx].algorithm != B43legacy_SEC_ALGO_NONE) {
                        /* Remove PROTECTED flag to mark it as decrypted. */
                        B43legacy_WARN_ON(!ieee80211_has_protected(fctl));
                        fctl &= ~cpu_to_le16(IEEE80211_FCTL_PROTECTED);
                        wlhdr->frame_control = fctl;

                        wlhdr_len = ieee80211_hdrlen(fctl);
                        if (unlikely(skb->len < (wlhdr_len + 3))) {
                                b43legacydbg(dev->wl, "RX: Packet size"
                                             " underrun3\n");
                                goto drop;
                        }
                        if (skb->data[wlhdr_len + 3] & (1 << 5)) {
                                /* The Ext-IV Bit is set in the "KeyID"
                                 * octet of the IV.
                                 */
                                iv_len = 8;
                                icv_len = 8;
                        } else {
                                iv_len = 4;
                                icv_len = 4;
                        }
                        if (unlikely(skb->len < (wlhdr_len + iv_len +
                            icv_len))) {
                                b43legacydbg(dev->wl, "RX: Packet size"
                                             " underrun4\n");
                                goto drop;
                        }
                        /* Remove the IV */
                        memmove(skb->data + iv_len, skb->data, wlhdr_len);
                        skb_pull(skb, iv_len);
                        /* Remove the ICV */
                        skb_trim(skb, skb->len - icv_len);

                        status.flag |= RX_FLAG_DECRYPTED;
                }
        }

        status.signal = b43legacy_rssi_postprocess(dev, jssi,
                                      (phystat0 & B43legacy_RX_PHYST0_OFDM),
                                      (phystat0 & B43legacy_RX_PHYST0_GAINCTL),
                                      (phystat3 & B43legacy_RX_PHYST3_TRSTATE));
        /* change to support A PHY */
        if (phystat0 & B43legacy_RX_PHYST0_OFDM)
                status.rate_idx = b43legacy_plcp_get_bitrate_idx_ofdm(plcp, false);
        else
                status.rate_idx = b43legacy_plcp_get_bitrate_idx_cck(plcp);
        status.antenna = !!(phystat0 & B43legacy_RX_PHYST0_ANT);

        /*
         * All frames on monitor interfaces and beacons always need a full
         * 64-bit timestamp. Monitor interfaces need it for diagnostic
         * purposes and beacons for IBSS merging.
         * This code assumes we get to process the packet within 16 bits
         * of timestamp, i.e. about 65 milliseconds after the PHY received
         * the first symbol.
         */
        if (ieee80211_is_beacon(fctl) || dev->wl->radiotap_enabled) {
                u16 low_mactime_now;

                b43legacy_tsf_read(dev, &status.mactime);
                low_mactime_now = status.mactime;
                status.mactime = status.mactime & ~0xFFFFULL;
                status.mactime += mactime;
                if (low_mactime_now <= mactime)
                        status.mactime -= 0x10000;
                status.flag |= RX_FLAG_MACTIME_START;
        }

        chanid = (chanstat & B43legacy_RX_CHAN_ID) >>
                  B43legacy_RX_CHAN_ID_SHIFT;
        switch (chanstat & B43legacy_RX_CHAN_PHYTYPE) {
        case B43legacy_PHYTYPE_B:
        case B43legacy_PHYTYPE_G:
                status.band = NL80211_BAND_2GHZ;
                status.freq = chanid + 2400;
                break;
        default:
                b43legacywarn(dev->wl, "Unexpected value for chanstat (0x%X)\n",
                       chanstat);
                goto drop;
        }

        memcpy(IEEE80211_SKB_RXCB(skb), &status, sizeof(status));
        ieee80211_rx_irqsafe(dev->wl->hw, skb);

        return;
drop:
        b43legacydbg(dev->wl, "RX: Packet dropped\n");
        dev_kfree_skb_any(skb);
}

void b43legacy_handle_txstatus(struct b43legacy_wldev *dev,
                             const struct b43legacy_txstatus *status)
{
        b43legacy_debugfs_log_txstat(dev, status);

        if (status->intermediate)
                return;
        if (status->for_ampdu)
                return;
        if (!status->acked)
                dev->wl->ieee_stats.dot11ACKFailureCount++;
        if (status->rts_count) {
                if (status->rts_count == 0xF) /* FIXME */
                        dev->wl->ieee_stats.dot11RTSFailureCount++;
                else
                        dev->wl->ieee_stats.dot11RTSSuccessCount++;
        }

        if (b43legacy_using_pio(dev))
                b43legacy_pio_handle_txstatus(dev, status);
        else
                b43legacy_dma_handle_txstatus(dev, status);
}

/* Handle TX status report as received through DMA/PIO queues */
void b43legacy_handle_hwtxstatus(struct b43legacy_wldev *dev,
                                 const struct b43legacy_hwtxstatus *hw)
{
        struct b43legacy_txstatus status;
        u8 tmp;

        status.cookie = le16_to_cpu(hw->cookie);
        status.seq = le16_to_cpu(hw->seq);
        status.phy_stat = hw->phy_stat;
        tmp = hw->count;
        status.frame_count = (tmp >> 4);
        status.rts_count = (tmp & 0x0F);
        tmp = hw->flags << 1;
        status.supp_reason = ((tmp & 0x1C) >> 2);
        status.pm_indicated = !!(tmp & 0x80);
        status.intermediate = !!(tmp & 0x40);
        status.for_ampdu = !!(tmp & 0x20);
        status.acked = !!(tmp & 0x02);

        b43legacy_handle_txstatus(dev, &status);
}

/* Stop any TX operation on the device (suspend the hardware queues) */
void b43legacy_tx_suspend(struct b43legacy_wldev *dev)
{
        if (b43legacy_using_pio(dev))
                b43legacy_pio_freeze_txqueues(dev);
        else
                b43legacy_dma_tx_suspend(dev);
}

/* Resume any TX operation on the device (resume the hardware queues) */
void b43legacy_tx_resume(struct b43legacy_wldev *dev)
{
        if (b43legacy_using_pio(dev))
                b43legacy_pio_thaw_txqueues(dev);
        else
                b43legacy_dma_tx_resume(dev);
}

/* Initialize the QoS parameters */
void b43legacy_qos_init(struct b43legacy_wldev *dev)
{
        /* FIXME: This function must probably be called from the mac80211
         * config callback. */
return;

        b43legacy_hf_write(dev, b43legacy_hf_read(dev) | B43legacy_HF_EDCF);
        /* FIXME kill magic */
        b43legacy_write16(dev, 0x688,
                          b43legacy_read16(dev, 0x688) | 0x4);


        /*TODO: We might need some stack support here to get the values. */
}