stf.c

Go to the documentation of this file.

/*
 * Copyright (c) 2010 Broadcom Corporation
 *
 * Permission to use, copy, modify, and/or distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
 * SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
 * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
 * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#include <net/mac80211.h>

#include "types.h"
#include "d11.h"
#include "rate.h"
#include "phy/phy_hal.h"
#include "channel.h"
#include "main.h"
#include "stf.h"

#define MIN_SPATIAL_EXPANSION   0
#define MAX_SPATIAL_EXPANSION   1

#define BRCMS_STF_SS_STBC_RX(wlc) (BRCMS_ISNPHY(wlc->band) && \
    NREV_GT(wlc->band->phyrev, 3) && NREV_LE(wlc->band->phyrev, 6))

#define NSTS_1  1
#define NSTS_2  2
#define NSTS_3  3
#define NSTS_4  4

static const u8 txcore_default[5] = {
    (0),            /* bitmap of the core enabled */
    (0x01),         /* For Nsts = 1, enable core 1 */
    (0x03),         /* For Nsts = 2, enable core 1 & 2 */
    (0x07),         /* For Nsts = 3, enable core 1, 2 & 3 */
    (0x0f)          /* For Nsts = 4, enable all cores */
};

static void brcms_c_stf_stbc_rx_ht_update(struct brcms_c_info *wlc, int val)
{
    /* MIMOPHYs rev3-6 cannot receive STBC with only one rx core active */
    if (BRCMS_STF_SS_STBC_RX(wlc)) {
        if ((wlc->stf->rxstreams == 1) && (val != HT_CAP_RX_STBC_NO))
            return;
    }

    if (wlc->pub->up) {
        brcms_c_update_beacon(wlc);
        brcms_c_update_probe_resp(wlc, true);
    }
}

/*
 * every WLC_TEMPSENSE_PERIOD seconds temperature check to decide whether to
 * turn on/off txchain.
 */
void brcms_c_tempsense_upd(struct brcms_c_info *wlc)
{
    struct brcms_phy_pub *pi = wlc->band->pi;
    uint active_chains, txchain;

    /* Check if the chip is too hot. Disable one Tx chain, if it is */
    /* high 4 bits are for Rx chain, low 4 bits are  for Tx chain */
    active_chains = wlc_phy_stf_chain_active_get(pi);
    txchain = active_chains & 0xf;

    if (wlc->stf->txchain == wlc->stf->hw_txchain) {
        if (txchain && (txchain < wlc->stf->hw_txchain))
            /* turn off 1 tx chain */
            brcms_c_stf_txchain_set(wlc, txchain, true);
    } else if (wlc->stf->txchain < wlc->stf->hw_txchain) {
        if (txchain == wlc->stf->hw_txchain)
            /* turn back on txchain */
            brcms_c_stf_txchain_set(wlc, txchain, true);
    }
}

void
brcms_c_stf_ss_algo_channel_get(struct brcms_c_info *wlc, u16 *ss_algo_channel,
                u16 chanspec)
{
    struct tx_power power;
    u8 siso_mcs_id, cdd_mcs_id, stbc_mcs_id;

    /* Clear previous settings */
    *ss_algo_channel = 0;

    if (!wlc->pub->up) {
        *ss_algo_channel = (u16) -1;
        return;
    }

    wlc_phy_txpower_get_current(wlc->band->pi, &power,
                    CHSPEC_CHANNEL(chanspec));

    siso_mcs_id = (CHSPEC_IS40(chanspec)) ?
        WL_TX_POWER_MCS40_SISO_FIRST : WL_TX_POWER_MCS20_SISO_FIRST;
    cdd_mcs_id = (CHSPEC_IS40(chanspec)) ?
        WL_TX_POWER_MCS40_CDD_FIRST : WL_TX_POWER_MCS20_CDD_FIRST;
    stbc_mcs_id = (CHSPEC_IS40(chanspec)) ?
        WL_TX_POWER_MCS40_STBC_FIRST : WL_TX_POWER_MCS20_STBC_FIRST;

    /* criteria to choose stf mode */

    /*
     * the "+3dbm (12 0.25db units)" is to account for the fact that with
     * CDD, tx occurs on both chains
     */
    if (power.target[siso_mcs_id] > (power.target[cdd_mcs_id] + 12))
        setbit(ss_algo_channel, PHY_TXC1_MODE_SISO);
    else
        setbit(ss_algo_channel, PHY_TXC1_MODE_CDD);

    /*
     * STBC is ORed into to algo channel as STBC requires per-packet SCB
     * capability check so cannot be default mode of operation. One of
     * SISO, CDD have to be set
     */
    if (power.target[siso_mcs_id] <= (power.target[stbc_mcs_id] + 12))
        setbit(ss_algo_channel, PHY_TXC1_MODE_STBC);
}

static bool brcms_c_stf_stbc_tx_set(struct brcms_c_info *wlc, s32 int_val)
{
    if ((int_val != AUTO) && (int_val != OFF) && (int_val != ON))
        return false;

    if ((int_val == ON) && (wlc->stf->txstreams == 1))
        return false;

    wlc->bandstate[BAND_2G_INDEX]->band_stf_stbc_tx = (s8) int_val;
    wlc->bandstate[BAND_5G_INDEX]->band_stf_stbc_tx = (s8) int_val;

    return true;
}

bool brcms_c_stf_stbc_rx_set(struct brcms_c_info *wlc, s32 int_val)
{
    if ((int_val != HT_CAP_RX_STBC_NO)
        && (int_val != HT_CAP_RX_STBC_ONE_STREAM))
        return false;

    if (BRCMS_STF_SS_STBC_RX(wlc)) {
        if ((int_val != HT_CAP_RX_STBC_NO)
            && (wlc->stf->rxstreams == 1))
            return false;
    }

    brcms_c_stf_stbc_rx_ht_update(wlc, int_val);
    return true;
}

static int brcms_c_stf_txcore_set(struct brcms_c_info *wlc, u8 Nsts,
                  u8 core_mask)
{
    BCMMSG(wlc->wiphy, "wl%d: Nsts %d core_mask %x\n",
         wlc->pub->unit, Nsts, core_mask);

    if (hweight8(core_mask) > wlc->stf->txstreams)
        core_mask = 0;

    if ((hweight8(core_mask) == wlc->stf->txstreams) &&
        ((core_mask & ~wlc->stf->txchain)
         || !(core_mask & wlc->stf->txchain)))
        core_mask = wlc->stf->txchain;

    wlc->stf->txcore[Nsts] = core_mask;
    /* Nsts = 1..4, txcore index = 1..4 */
    if (Nsts == 1) {
        /* Needs to update beacon and ucode generated response
         * frames when 1 stream core map changed
         */
        wlc->stf->phytxant = core_mask << PHY_TXC_ANT_SHIFT;
        brcms_b_txant_set(wlc->hw, wlc->stf->phytxant);
        if (wlc->clk) {
            brcms_c_suspend_mac_and_wait(wlc);
            brcms_c_beacon_phytxctl_txant_upd(wlc, wlc->bcn_rspec);
            brcms_c_enable_mac(wlc);
        }
    }

    return 0;
}

static int brcms_c_stf_spatial_policy_set(struct brcms_c_info *wlc, int val)
{
    int i;
    u8 core_mask = 0;

    BCMMSG(wlc->wiphy, "wl%d: val %x\n", wlc->pub->unit, val);

    wlc->stf->spatial_policy = (s8) val;
    for (i = 1; i <= MAX_STREAMS_SUPPORTED; i++) {
        core_mask = (val == MAX_SPATIAL_EXPANSION) ?
            wlc->stf->txchain : txcore_default[i];
        brcms_c_stf_txcore_set(wlc, (u8) i, core_mask);
    }
    return 0;
}

/*
 * Centralized txant update function. call it whenever wlc->stf->txant and/or
 * wlc->stf->txchain change.
 *
 * Antennas are controlled by ucode indirectly, which drives PHY or GPIO to
 * achieve various tx/rx antenna selection schemes
 *
 * legacy phy, bit 6 and bit 7 means antenna 0 and 1 respectively, bit6+bit7
 * means auto(last rx).
 * for NREV<3, bit 6 and bit 7 means antenna 0 and 1 respectively, bit6+bit7
 * means last rx and do tx-antenna selection for SISO transmissions
 * for NREV=3, bit 6 and bit _8_ means antenna 0 and 1 respectively, bit6+bit7
 * means last rx and do tx-antenna selection for SISO transmissions
 * for NREV>=7, bit 6 and bit 7 mean antenna 0 and 1 respectively, nit6+bit7
 * means both cores active
*/
static void _brcms_c_stf_phy_txant_upd(struct brcms_c_info *wlc)
{
    s8 txant;

    txant = (s8) wlc->stf->txant;
    if (BRCMS_PHY_11N_CAP(wlc->band)) {
        if (txant == ANT_TX_FORCE_0) {
            wlc->stf->phytxant = PHY_TXC_ANT_0;
        } else if (txant == ANT_TX_FORCE_1) {
            wlc->stf->phytxant = PHY_TXC_ANT_1;

            if (BRCMS_ISNPHY(wlc->band) &&
                NREV_GE(wlc->band->phyrev, 3)
                && NREV_LT(wlc->band->phyrev, 7))
                wlc->stf->phytxant = PHY_TXC_ANT_2;
        } else {
            if (BRCMS_ISLCNPHY(wlc->band) ||
                BRCMS_ISSSLPNPHY(wlc->band))
                wlc->stf->phytxant = PHY_TXC_LCNPHY_ANT_LAST;
            else {
                /* catch out of sync wlc->stf->txcore */
                WARN_ON(wlc->stf->txchain <= 0);
                wlc->stf->phytxant =
                    wlc->stf->txchain << PHY_TXC_ANT_SHIFT;
            }
        }
    } else {
        if (txant == ANT_TX_FORCE_0)
            wlc->stf->phytxant = PHY_TXC_OLD_ANT_0;
        else if (txant == ANT_TX_FORCE_1)
            wlc->stf->phytxant = PHY_TXC_OLD_ANT_1;
        else
            wlc->stf->phytxant = PHY_TXC_OLD_ANT_LAST;
    }

    brcms_b_txant_set(wlc->hw, wlc->stf->phytxant);
}

int brcms_c_stf_txchain_set(struct brcms_c_info *wlc, s32 int_val, bool force)
{
    u8 txchain = (u8) int_val;
    u8 txstreams;
    uint i;

    if (wlc->stf->txchain == txchain)
        return 0;

    if ((txchain & ~wlc->stf->hw_txchain)
        || !(txchain & wlc->stf->hw_txchain))
        return -EINVAL;

    /*
     * if nrate override is configured to be non-SISO STF mode, reject
     * reducing txchain to 1
     */
    txstreams = (u8) hweight8(txchain);
    if (txstreams > MAX_STREAMS_SUPPORTED)
        return -EINVAL;

    wlc->stf->txchain = txchain;
    wlc->stf->txstreams = txstreams;
    brcms_c_stf_stbc_tx_set(wlc, wlc->band->band_stf_stbc_tx);
    brcms_c_stf_ss_update(wlc, wlc->bandstate[BAND_2G_INDEX]);
    brcms_c_stf_ss_update(wlc, wlc->bandstate[BAND_5G_INDEX]);
    wlc->stf->txant =
        (wlc->stf->txstreams == 1) ? ANT_TX_FORCE_0 : ANT_TX_DEF;
    _brcms_c_stf_phy_txant_upd(wlc);

    wlc_phy_stf_chain_set(wlc->band->pi, wlc->stf->txchain,
                  wlc->stf->rxchain);

    for (i = 1; i <= MAX_STREAMS_SUPPORTED; i++)
        brcms_c_stf_txcore_set(wlc, (u8) i, txcore_default[i]);

    return 0;
}

/*
 * update wlc->stf->ss_opmode which represents the operational stf_ss mode
 * we're using
 */
int brcms_c_stf_ss_update(struct brcms_c_info *wlc, struct brcms_band *band)
{
    int ret_code = 0;
    u8 prev_stf_ss;
    u8 upd_stf_ss;

    prev_stf_ss = wlc->stf->ss_opmode;

    /*
     * NOTE: opmode can only be SISO or CDD as STBC is decided on a
     * per-packet basis
     */
    if (BRCMS_STBC_CAP_PHY(wlc) &&
        wlc->stf->ss_algosel_auto
        && (wlc->stf->ss_algo_channel != (u16) -1)) {
        upd_stf_ss = (wlc->stf->txstreams == 1 ||
                  isset(&wlc->stf->ss_algo_channel,
                    PHY_TXC1_MODE_SISO)) ?
                    PHY_TXC1_MODE_SISO : PHY_TXC1_MODE_CDD;
    } else {
        if (wlc->band != band)
            return ret_code;
        upd_stf_ss = (wlc->stf->txstreams == 1) ?
                PHY_TXC1_MODE_SISO : band->band_stf_ss_mode;
    }
    if (prev_stf_ss != upd_stf_ss) {
        wlc->stf->ss_opmode = upd_stf_ss;
        brcms_b_band_stf_ss_set(wlc->hw, upd_stf_ss);
    }

    return ret_code;
}

int brcms_c_stf_attach(struct brcms_c_info *wlc)
{
    wlc->bandstate[BAND_2G_INDEX]->band_stf_ss_mode = PHY_TXC1_MODE_SISO;
    wlc->bandstate[BAND_5G_INDEX]->band_stf_ss_mode = PHY_TXC1_MODE_CDD;

    if (BRCMS_ISNPHY(wlc->band) &&
        (wlc_phy_txpower_hw_ctrl_get(wlc->band->pi) != PHY_TPC_HW_ON))
        wlc->bandstate[BAND_2G_INDEX]->band_stf_ss_mode =
            PHY_TXC1_MODE_CDD;
    brcms_c_stf_ss_update(wlc, wlc->bandstate[BAND_2G_INDEX]);
    brcms_c_stf_ss_update(wlc, wlc->bandstate[BAND_5G_INDEX]);

    brcms_c_stf_stbc_rx_ht_update(wlc, HT_CAP_RX_STBC_NO);
    wlc->bandstate[BAND_2G_INDEX]->band_stf_stbc_tx = OFF;
    wlc->bandstate[BAND_5G_INDEX]->band_stf_stbc_tx = OFF;

    if (BRCMS_STBC_CAP_PHY(wlc)) {
        wlc->stf->ss_algosel_auto = true;
        /* Init the default value */
        wlc->stf->ss_algo_channel = (u16) -1;
    }
    return 0;
}

void brcms_c_stf_detach(struct brcms_c_info *wlc)
{
}

void brcms_c_stf_phy_txant_upd(struct brcms_c_info *wlc)
{
    _brcms_c_stf_phy_txant_upd(wlc);
}

void brcms_c_stf_phy_chain_calc(struct brcms_c_info *wlc)
{
    struct ssb_sprom *sprom = &wlc->hw->d11core->bus->sprom;

    /* get available rx/tx chains */
    wlc->stf->hw_txchain = sprom->txchain;
    wlc->stf->hw_rxchain = sprom->rxchain;

    /* these parameter are intended to be used for all PHY types */
    if (wlc->stf->hw_txchain == 0 || wlc->stf->hw_txchain == 0xf) {
        if (BRCMS_ISNPHY(wlc->band))
            wlc->stf->hw_txchain = TXCHAIN_DEF_NPHY;
        else
            wlc->stf->hw_txchain = TXCHAIN_DEF;
    }

    wlc->stf->txchain = wlc->stf->hw_txchain;
    wlc->stf->txstreams = (u8) hweight8(wlc->stf->hw_txchain);

    if (wlc->stf->hw_rxchain == 0 || wlc->stf->hw_rxchain == 0xf) {
        if (BRCMS_ISNPHY(wlc->band))
            wlc->stf->hw_rxchain = RXCHAIN_DEF_NPHY;
        else
            wlc->stf->hw_rxchain = RXCHAIN_DEF;
    }

    wlc->stf->rxchain = wlc->stf->hw_rxchain;
    wlc->stf->rxstreams = (u8) hweight8(wlc->stf->hw_rxchain);

    /* initialize the txcore table */
    memcpy(wlc->stf->txcore, txcore_default, sizeof(wlc->stf->txcore));

    /* default spatial_policy */
    wlc->stf->spatial_policy = MIN_SPATIAL_EXPANSION;
    brcms_c_stf_spatial_policy_set(wlc, MIN_SPATIAL_EXPANSION);
}

static u16 _brcms_c_stf_phytxchain_sel(struct brcms_c_info *wlc,
                       u32 rspec)
{
    u16 phytxant = wlc->stf->phytxant;

    if (rspec_stf(rspec) != PHY_TXC1_MODE_SISO)
        phytxant = wlc->stf->txchain << PHY_TXC_ANT_SHIFT;
    else if (wlc->stf->txant == ANT_TX_DEF)
        phytxant = wlc->stf->txchain << PHY_TXC_ANT_SHIFT;
    phytxant &= PHY_TXC_ANT_MASK;
    return phytxant;
}

u16 brcms_c_stf_phytxchain_sel(struct brcms_c_info *wlc, u32 rspec)
{
    return _brcms_c_stf_phytxchain_sel(wlc, rspec);
}

u16 brcms_c_stf_d11hdrs_phyctl_txant(struct brcms_c_info *wlc, u32 rspec)
{
    u16 phytxant = wlc->stf->phytxant;
    u16 mask = PHY_TXC_ANT_MASK;

    /* for non-siso rates or default setting, use the available chains */
    if (BRCMS_ISNPHY(wlc->band)) {
        phytxant = _brcms_c_stf_phytxchain_sel(wlc, rspec);
        mask = PHY_TXC_HTANT_MASK;
    }
    phytxant |= phytxant & mask;
    return phytxant;
}