xmit.c

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/*

  Broadcom B43legacy wireless driver

  Transmission (TX/RX) related functions.

  Copyright (C) 2005 Martin Langer <[email protected]>
  Copyright (C) 2005 Stefano Brivio <[email protected]>
  Copyright (C) 2005, 2006 Michael Buesch <[email protected]>
  Copyright (C) 2005 Danny van Dyk <[email protected]>
  Copyright (C) 2005 Andreas Jaggi <[email protected]>
  Copyright (C) 2007 Larry Finger <[email protected]>

  This program is free software; you can redistribute it and/or modify
  it under the terms of the GNU General Public License as published by
  the Free Software Foundation; either version 2 of the License, or
  (at your option) any later version.

  This program is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  GNU General Public License for more details.

  You should have received a copy of the GNU General Public License
  along with this program; see the file COPYING.  If not, write to
  the Free Software Foundation, Inc., 51 Franklin Steet, Fifth Floor,
  Boston, MA 02110-1301, USA.

*/

#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, 6);

    /* 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((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_MPDU;
    }

    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 = IEEE80211_BAND_2GHZ;
        status.freq = chanid + 2400;
        break;
    default:
        b43legacywarn(dev->wl, "Unexpected value for chanstat (0x%X)\n",
               chanstat);
    }

    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. */
}