/*-
 * SPDX-License-Identifier: ISC
 *
 * Copyright (c) 2002-2009 Sam Leffler, Errno Consulting
 * Copyright (c) 2002-2008 Atheros Communications, Inc.
 *
 * 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 "opt_ah.h"

/*
 * XXX this is virtually the same code as for 5212; we reuse
 * storage in the 5212 state block; need to refactor.
 */
#include "ah.h"
#include "ah_internal.h"
#include "ah_desc.h"

#include "ar5416/ar5416.h"
#include "ar5416/ar5416reg.h"
#include "ar5416/ar5416phy.h"

/*
 * Anti noise immunity support.  We track phy errors and react
 * to excessive errors by adjusting the noise immunity parameters.
 */

#define HAL_EP_RND(x, mul) \
        ((((x)%(mul)) >= ((mul)/2)) ? ((x) + ((mul) - 1)) / (mul) : (x)/(mul))
#define BEACON_RSSI(ahp) \
        HAL_EP_RND(ahp->ah_stats.ast_nodestats.ns_avgbrssi, \
                HAL_RSSI_EP_MULTIPLIER)

/*
 * ANI processing tunes radio parameters according to PHY errors
 * and related information.  This is done for noise and spur
 * immunity in all operating modes if the device indicates it's
 * capable at attach time.  In addition, when there is a reference
 * rssi value (e.g. beacon frames from an ap in station mode)
 * further tuning is done.
 *
 * ANI_ENA indicates whether any ANI processing should be done;
 * this is specified at attach time.
 *
 * ANI_ENA_RSSI indicates whether rssi-based processing should
 * done, this is enabled based on operating mode and is meaningful
 * only if ANI_ENA is true.
 *
 * ANI parameters are typically controlled only by the hal.  The
 * AniControl interface however permits manual tuning through the
 * diagnostic api.
 */
#define ANI_ENA(ah) \
        (AH5212(ah)->ah_procPhyErr & HAL_ANI_ENA)
#define ANI_ENA_RSSI(ah) \
        (AH5212(ah)->ah_procPhyErr & HAL_RSSI_ANI_ENA)

#define ah_mibStats     ah_stats.ast_mibstats

static void
enableAniMIBCounters(struct ath_hal *ah, const struct ar5212AniParams *params)
{
        struct ath_hal_5212 *ahp = AH5212(ah);

        HALDEBUG(ah, HAL_DEBUG_ANI, "%s: Enable mib counters: "
            "OfdmPhyErrBase 0x%x cckPhyErrBase 0x%x\n",
            __func__, params->ofdmPhyErrBase, params->cckPhyErrBase);

        OS_REG_WRITE(ah, AR_FILTOFDM, 0);
        OS_REG_WRITE(ah, AR_FILTCCK, 0);

        OS_REG_WRITE(ah, AR_PHYCNT1, params->ofdmPhyErrBase);
        OS_REG_WRITE(ah, AR_PHYCNT2, params->cckPhyErrBase);
        OS_REG_WRITE(ah, AR_PHY_ERR_MASK_1, AR_PHY_ERR_OFDM_TIMING);
        OS_REG_WRITE(ah, AR_PHY_ERR_MASK_2, AR_PHY_ERR_CCK_TIMING);

        ar5212UpdateMibCounters(ah, &ahp->ah_mibStats); /* save+clear counters*/
        ar5212EnableMibCounters(ah);                    /* enable everything */
}

static void 
disableAniMIBCounters(struct ath_hal *ah)
{
        struct ath_hal_5212 *ahp = AH5212(ah);

        HALDEBUG(ah, HAL_DEBUG_ANI, "Disable MIB counters\n");

        ar5212UpdateMibCounters(ah, &ahp->ah_mibStats); /* save stats */
        ar5212DisableMibCounters(ah);                   /* disable everything */

        OS_REG_WRITE(ah, AR_PHY_ERR_MASK_1, 0);
        OS_REG_WRITE(ah, AR_PHY_ERR_MASK_2, 0);
}

static void
setPhyErrBase(struct ath_hal *ah, struct ar5212AniParams *params)
{
        if (params->ofdmTrigHigh >= AR_PHY_COUNTMAX) {
                HALDEBUG(ah, HAL_DEBUG_ANY,
                    "OFDM Trigger %d is too high for hw counters, using max\n",
                    params->ofdmTrigHigh);
                params->ofdmPhyErrBase = 0;
        } else
                params->ofdmPhyErrBase = AR_PHY_COUNTMAX - params->ofdmTrigHigh;
        if (params->cckTrigHigh >= AR_PHY_COUNTMAX) {
                HALDEBUG(ah, HAL_DEBUG_ANY,
                    "CCK Trigger %d is too high for hw counters, using max\n",
                    params->cckTrigHigh);
                params->cckPhyErrBase = 0;
        } else
                params->cckPhyErrBase = AR_PHY_COUNTMAX - params->cckTrigHigh;
}

/*
 * Setup ANI handling.  Sets all thresholds and reset the
 * channel statistics.  Note that ar5416AniReset should be
 * called by ar5416Reset before anything else happens and
 * that's where we force initial settings.
 */
void
ar5416AniAttach(struct ath_hal *ah, const struct ar5212AniParams *params24,
        const struct ar5212AniParams *params5, HAL_BOOL enable)
{
        struct ath_hal_5212 *ahp = AH5212(ah);

        if (params24 != AH_NULL) {
                OS_MEMCPY(&ahp->ah_aniParams24, params24, sizeof(*params24));
                setPhyErrBase(ah, &ahp->ah_aniParams24);
        }
        if (params5 != AH_NULL) {
                OS_MEMCPY(&ahp->ah_aniParams5, params5, sizeof(*params5));
                setPhyErrBase(ah, &ahp->ah_aniParams5);
        }

        OS_MEMZERO(ahp->ah_ani, sizeof(ahp->ah_ani));
        /* Enable MIB Counters */
        enableAniMIBCounters(ah, &ahp->ah_aniParams24 /*XXX*/);

        if (enable) {           /* Enable ani now */
                HALASSERT(params24 != AH_NULL && params5 != AH_NULL);
                ahp->ah_procPhyErr |= HAL_ANI_ENA;
        } else {
                ahp->ah_procPhyErr &= ~HAL_ANI_ENA;
        }
}

/*
 * Cleanup any ANI state setup.
 *
 * This doesn't restore registers to their default settings!
 */
void
ar5416AniDetach(struct ath_hal *ah)
{
        HALDEBUG(ah, HAL_DEBUG_ANI, "Detaching Ani\n");
        disableAniMIBCounters(ah);
}

/*
 * Control Adaptive Noise Immunity Parameters
 */
HAL_BOOL
ar5416AniControl(struct ath_hal *ah, HAL_ANI_CMD cmd, int param)
{
        typedef int TABLE[];
        struct ath_hal_5212 *ahp = AH5212(ah);
        struct ar5212AniState *aniState = ahp->ah_curani;
        const struct ar5212AniParams *params = AH_NULL;

        /*
         * This function may be called before there's a current
         * channel (eg to disable ANI.)
         */
        if (aniState != AH_NULL)
                params = aniState->params;

        OS_MARK(ah, AH_MARK_ANI_CONTROL, cmd);

        /* These commands can't be disabled */
        if (cmd == HAL_ANI_PRESENT)
                return AH_TRUE;

        if (cmd == HAL_ANI_MODE) {
                if (param == 0) {
                        ahp->ah_procPhyErr &= ~HAL_ANI_ENA;
                        /* Turn off HW counters if we have them */
                        ar5416AniDetach(ah);
                } else {                        /* normal/auto mode */
                        /* don't mess with state if already enabled */
                        if (! (ahp->ah_procPhyErr & HAL_ANI_ENA)) {
                                /* Enable MIB Counters */
                                /*
                                 * XXX use 2.4ghz params if no channel is
                                 * available
                                 */
                                enableAniMIBCounters(ah,
                                    ahp->ah_curani != AH_NULL ?
                                      ahp->ah_curani->params:
                                      &ahp->ah_aniParams24);
                                ahp->ah_procPhyErr |= HAL_ANI_ENA;
                        }
                }
                return AH_TRUE;
        }

        /* Check whether the particular function is enabled */
        if (((1 << cmd) & AH5416(ah)->ah_ani_function) == 0) {
                HALDEBUG(ah, HAL_DEBUG_ANI, "%s: command %d disabled\n",
                    __func__, cmd);
                HALDEBUG(ah, HAL_DEBUG_ANI, "%s: cmd %d; mask %x\n", __func__, cmd, AH5416(ah)->ah_ani_function);
                return AH_FALSE;
        }

        switch (cmd) {
        case HAL_ANI_NOISE_IMMUNITY_LEVEL: {
                u_int level = param;

                HALDEBUG(ah, HAL_DEBUG_ANI, "%s: HAL_ANI_NOISE_IMMUNITY_LEVEL: set level = %d\n", __func__, level);
                if (level > params->maxNoiseImmunityLevel) {
                        HALDEBUG(ah, HAL_DEBUG_ANI,
                            "%s: immunity level out of range (%u > %u)\n",
                            __func__, level, params->maxNoiseImmunityLevel);
                        return AH_FALSE;
                }

                OS_REG_RMW_FIELD(ah, AR_PHY_DESIRED_SZ,
                    AR_PHY_DESIRED_SZ_TOT_DES, params->totalSizeDesired[level]);
                OS_REG_RMW_FIELD(ah, AR_PHY_AGC_CTL1,
                    AR_PHY_AGC_CTL1_COARSE_LOW, params->coarseLow[level]);
                OS_REG_RMW_FIELD(ah, AR_PHY_AGC_CTL1,
                    AR_PHY_AGC_CTL1_COARSE_HIGH, params->coarseHigh[level]);
                OS_REG_RMW_FIELD(ah, AR_PHY_FIND_SIG,
                    AR_PHY_FIND_SIG_FIRPWR, params->firpwr[level]);

                if (level > aniState->noiseImmunityLevel)
                        ahp->ah_stats.ast_ani_niup++;
                else if (level < aniState->noiseImmunityLevel)
                        ahp->ah_stats.ast_ani_nidown++;
                aniState->noiseImmunityLevel = level;
                break;
        }
        case HAL_ANI_OFDM_WEAK_SIGNAL_DETECTION: {
                static const TABLE m1ThreshLow   = { 127,   50 };
                static const TABLE m2ThreshLow   = { 127,   40 };
                static const TABLE m1Thresh      = { 127, 0x4d };
                static const TABLE m2Thresh      = { 127, 0x40 };
                static const TABLE m2CountThr    = {  31,   16 };
                static const TABLE m2CountThrLow = {  63,   48 };
                u_int on = param ? 1 : 0;

                HALDEBUG(ah, HAL_DEBUG_ANI, "%s: HAL_ANI_OFDM_WEAK_SIGNAL_DETECTION: %s\n", __func__, on ? "enabled" : "disabled");
                OS_REG_RMW_FIELD(ah, AR_PHY_SFCORR_LOW,
                        AR_PHY_SFCORR_LOW_M1_THRESH_LOW, m1ThreshLow[on]);
                OS_REG_RMW_FIELD(ah, AR_PHY_SFCORR_LOW,
                        AR_PHY_SFCORR_LOW_M2_THRESH_LOW, m2ThreshLow[on]);
                OS_REG_RMW_FIELD(ah, AR_PHY_SFCORR,
                        AR_PHY_SFCORR_M1_THRESH, m1Thresh[on]);
                OS_REG_RMW_FIELD(ah, AR_PHY_SFCORR,
                        AR_PHY_SFCORR_M2_THRESH, m2Thresh[on]);
                OS_REG_RMW_FIELD(ah, AR_PHY_SFCORR,
                        AR_PHY_SFCORR_M2COUNT_THR, m2CountThr[on]);
                OS_REG_RMW_FIELD(ah, AR_PHY_SFCORR_LOW,
                        AR_PHY_SFCORR_LOW_M2COUNT_THR_LOW, m2CountThrLow[on]);

                OS_REG_RMW_FIELD(ah, AR_PHY_SFCORR_EXT,
                        AR_PHY_SFCORR_EXT_M1_THRESH_LOW, m1ThreshLow[on]);
                OS_REG_RMW_FIELD(ah, AR_PHY_SFCORR_EXT,
                        AR_PHY_SFCORR_EXT_M2_THRESH_LOW, m2ThreshLow[on]);
                OS_REG_RMW_FIELD(ah, AR_PHY_SFCORR_EXT,
                        AR_PHY_SFCORR_EXT_M1_THRESH, m1Thresh[on]);
                OS_REG_RMW_FIELD(ah, AR_PHY_SFCORR_EXT,
                        AR_PHY_SFCORR_EXT_M2_THRESH, m2Thresh[on]);

                if (on) {
                        OS_REG_SET_BIT(ah, AR_PHY_SFCORR_LOW,
                                AR_PHY_SFCORR_LOW_USE_SELF_CORR_LOW);
                } else {
                        OS_REG_CLR_BIT(ah, AR_PHY_SFCORR_LOW,
                                AR_PHY_SFCORR_LOW_USE_SELF_CORR_LOW);
                }
                if (on)
                        ahp->ah_stats.ast_ani_ofdmon++;
                else
                        ahp->ah_stats.ast_ani_ofdmoff++;
                aniState->ofdmWeakSigDetectOff = !on;
                break;
        }
        case HAL_ANI_CCK_WEAK_SIGNAL_THR: {
                static const TABLE weakSigThrCck = { 8, 6 };
                u_int high = param ? 1 : 0;

                HALDEBUG(ah, HAL_DEBUG_ANI, "%s: HAL_ANI_CCK_WEAK_SIGNAL_THR: %s\n", __func__, high ? "high" : "low");
                OS_REG_RMW_FIELD(ah, AR_PHY_CCK_DETECT,
                    AR_PHY_CCK_DETECT_WEAK_SIG_THR_CCK, weakSigThrCck[high]);
                if (high)
                        ahp->ah_stats.ast_ani_cckhigh++;
                else
                        ahp->ah_stats.ast_ani_ccklow++;
                aniState->cckWeakSigThreshold = high;
                break;
        }
        case HAL_ANI_FIRSTEP_LEVEL: {
                u_int level = param;

                HALDEBUG(ah, HAL_DEBUG_ANI, "%s: HAL_ANI_FIRSTEP_LEVEL: level = %d\n", __func__, level);
                if (level > params->maxFirstepLevel) {
                        HALDEBUG(ah, HAL_DEBUG_ANI,
                            "%s: firstep level out of range (%u > %u)\n",
                            __func__, level, params->maxFirstepLevel);
                        return AH_FALSE;
                }
                OS_REG_RMW_FIELD(ah, AR_PHY_FIND_SIG,
                    AR_PHY_FIND_SIG_FIRSTEP, params->firstep[level]);
                if (level > aniState->firstepLevel)
                        ahp->ah_stats.ast_ani_stepup++;
                else if (level < aniState->firstepLevel)
                        ahp->ah_stats.ast_ani_stepdown++;
                aniState->firstepLevel = level;
                break;
        }
        case HAL_ANI_SPUR_IMMUNITY_LEVEL: {
                u_int level = param;

                HALDEBUG(ah, HAL_DEBUG_ANI, "%s: HAL_ANI_SPUR_IMMUNITY_LEVEL: level = %d\n", __func__, level);
                if (level > params->maxSpurImmunityLevel) {
                        HALDEBUG(ah, HAL_DEBUG_ANI,
                            "%s: spur immunity level out of range (%u > %u)\n",
                            __func__, level, params->maxSpurImmunityLevel);
                        return AH_FALSE;
                }
                OS_REG_RMW_FIELD(ah, AR_PHY_TIMING5,
                    AR_PHY_TIMING5_CYCPWR_THR1, params->cycPwrThr1[level]);

                if (level > aniState->spurImmunityLevel)
                        ahp->ah_stats.ast_ani_spurup++;
                else if (level < aniState->spurImmunityLevel)
                        ahp->ah_stats.ast_ani_spurdown++;
                aniState->spurImmunityLevel = level;
                break;
        }
#ifdef AH_PRIVATE_DIAG
        case HAL_ANI_PHYERR_RESET:
                ahp->ah_stats.ast_ani_ofdmerrs = 0;
                ahp->ah_stats.ast_ani_cckerrs = 0;
                break;
#endif /* AH_PRIVATE_DIAG */
        default:
                HALDEBUG(ah, HAL_DEBUG_ANI, "%s: invalid cmd %u\n",
                    __func__, cmd);
                return AH_FALSE;
        }
        return AH_TRUE;
}

static void
ar5416AniOfdmErrTrigger(struct ath_hal *ah)
{
        struct ath_hal_5212 *ahp = AH5212(ah);
        const struct ieee80211_channel *chan = AH_PRIVATE(ah)->ah_curchan;
        struct ar5212AniState *aniState;
        const struct ar5212AniParams *params;

        HALASSERT(chan != AH_NULL);

        if (!ANI_ENA(ah))
                return;

        aniState = ahp->ah_curani;
        params = aniState->params;
        /* First, raise noise immunity level, up to max */
        if (aniState->noiseImmunityLevel+1 < params->maxNoiseImmunityLevel) {
                if (ar5416AniControl(ah, HAL_ANI_NOISE_IMMUNITY_LEVEL, 
                                 aniState->noiseImmunityLevel + 1))
                        return;
        }
        /* then, raise spur immunity level, up to max */
        if (aniState->spurImmunityLevel+1 < params->maxSpurImmunityLevel) {
                if (ar5416AniControl(ah, HAL_ANI_SPUR_IMMUNITY_LEVEL,
                                 aniState->spurImmunityLevel + 1))
                        return;
        }

        /*
         * In the case of AP mode operation, we cannot bucketize beacons
         * according to RSSI.  Instead, raise Firstep level, up to max, and
         * simply return.
         */
        if (AH_PRIVATE(ah)->ah_opmode == HAL_M_HOSTAP) {
                if (aniState->firstepLevel < params->maxFirstepLevel) {
                        if (ar5416AniControl(ah, HAL_ANI_FIRSTEP_LEVEL,
                            aniState->firstepLevel + 1))
                                return;
                }
        }
        if (ANI_ENA_RSSI(ah)) {
                int32_t rssi = BEACON_RSSI(ahp);
                if (rssi > params->rssiThrHigh) {
                        /*
                         * Beacon rssi is high, can turn off ofdm
                         * weak sig detect.
                         */
                        if (!aniState->ofdmWeakSigDetectOff) {
                                ar5416AniControl(ah,
                                    HAL_ANI_OFDM_WEAK_SIGNAL_DETECTION,
                                    AH_FALSE);
                                ar5416AniControl(ah,
                                    HAL_ANI_SPUR_IMMUNITY_LEVEL, 0);
                                return;
                        }
                        /* 
                         * If weak sig detect is already off, as last resort,
                         * raise firstep level 
                         */
                        if (aniState->firstepLevel < params->maxFirstepLevel) {
                                if (ar5416AniControl(ah, HAL_ANI_FIRSTEP_LEVEL,
                                                 aniState->firstepLevel + 1))
                                        return;
                        }
                } else if (rssi > params->rssiThrLow) {
                        /* 
                         * Beacon rssi in mid range, need ofdm weak signal
                         * detect, but we can raise firststepLevel.
                         */
                        if (aniState->ofdmWeakSigDetectOff)
                                ar5416AniControl(ah,
                                    HAL_ANI_OFDM_WEAK_SIGNAL_DETECTION,
                                    AH_TRUE);
                        if (aniState->firstepLevel < params->maxFirstepLevel)
                                if (ar5416AniControl(ah, HAL_ANI_FIRSTEP_LEVEL,
                                     aniState->firstepLevel + 1))
                                return;
                } else {
                        /* 
                         * Beacon rssi is low, if in 11b/g mode, turn off ofdm
                         * weak signal detection and zero firstepLevel to
                         * maximize CCK sensitivity 
                         */
                        if (IEEE80211_IS_CHAN_CCK(chan)) {
                                if (!aniState->ofdmWeakSigDetectOff)
                                        ar5416AniControl(ah,
                                            HAL_ANI_OFDM_WEAK_SIGNAL_DETECTION,
                                            AH_FALSE);
                                if (aniState->firstepLevel > 0)
                                        if (ar5416AniControl(ah,
                                             HAL_ANI_FIRSTEP_LEVEL, 0))
                                                return;
                        }
                }
        }
}

static void
ar5416AniCckErrTrigger(struct ath_hal *ah)
{
        struct ath_hal_5212 *ahp = AH5212(ah);
        const struct ieee80211_channel *chan = AH_PRIVATE(ah)->ah_curchan;
        struct ar5212AniState *aniState;
        const struct ar5212AniParams *params;

        HALASSERT(chan != AH_NULL);

        if (!ANI_ENA(ah))
                return;

        /* first, raise noise immunity level, up to max */
        aniState = ahp->ah_curani;
        params = aniState->params;
        if ((AH5416(ah)->ah_ani_function & (1 << HAL_ANI_NOISE_IMMUNITY_LEVEL) &&
            aniState->noiseImmunityLevel+1 < params->maxNoiseImmunityLevel)) {
                ar5416AniControl(ah, HAL_ANI_NOISE_IMMUNITY_LEVEL,
                                 aniState->noiseImmunityLevel + 1);
                return;
        }

        if (ANI_ENA_RSSI(ah)) {
                int32_t rssi = BEACON_RSSI(ahp);
                if (rssi >  params->rssiThrLow) {
                        /*
                         * Beacon signal in mid and high range,
                         * raise firstep level.
                         */
                        if (aniState->firstepLevel < params->maxFirstepLevel)
                                ar5416AniControl(ah, HAL_ANI_FIRSTEP_LEVEL,
                                                 aniState->firstepLevel + 1);
                } else {
                        /*
                         * Beacon rssi is low, zero firstep level to maximize
                         * CCK sensitivity in 11b/g mode.
                         */
                        if (IEEE80211_IS_CHAN_CCK(chan)) {
                                if (aniState->firstepLevel > 0)
                                        ar5416AniControl(ah,
                                            HAL_ANI_FIRSTEP_LEVEL, 0);
                        }
                }
        }
}

static void
ar5416AniRestart(struct ath_hal *ah, struct ar5212AniState *aniState)
{
        struct ath_hal_5212 *ahp = AH5212(ah);
        const struct ar5212AniParams *params = aniState->params;

        aniState->listenTime = 0;
        /*
         * NB: these are written on reset based on the
         *     ini so we must re-write them!
         */
        HALDEBUG(ah, HAL_DEBUG_ANI,
            "%s: Writing ofdmbase=%u   cckbase=%u\n", __func__,
            params->ofdmPhyErrBase, params->cckPhyErrBase);
        OS_REG_WRITE(ah, AR_PHY_ERR_1, params->ofdmPhyErrBase);
        OS_REG_WRITE(ah, AR_PHY_ERR_2, params->cckPhyErrBase);
        OS_REG_WRITE(ah, AR_PHY_ERR_MASK_1, AR_PHY_ERR_OFDM_TIMING);
        OS_REG_WRITE(ah, AR_PHY_ERR_MASK_2, AR_PHY_ERR_CCK_TIMING);

        /* Clear the mib counters and save them in the stats */
        ar5212UpdateMibCounters(ah, &ahp->ah_mibStats);
        aniState->ofdmPhyErrCount = 0;
        aniState->cckPhyErrCount = 0;
}

/*
 * Restore/reset the ANI parameters and reset the statistics.
 * This routine must be called for every channel change.
 *
 * NOTE: This is where ah_curani is set; other ani code assumes
 *       it is setup to reflect the current channel.
 */
void
ar5416AniReset(struct ath_hal *ah, const struct ieee80211_channel *chan,
        HAL_OPMODE opmode, int restore)
{
        struct ath_hal_5212 *ahp = AH5212(ah);
        HAL_CHANNEL_INTERNAL *ichan = ath_hal_checkchannel(ah, chan);
        /* XXX bounds check ic_devdata */
        struct ar5212AniState *aniState = &ahp->ah_ani[chan->ic_devdata];
        uint32_t rxfilter;

        if ((ichan->privFlags & CHANNEL_ANI_INIT) == 0) {
                OS_MEMZERO(aniState, sizeof(*aniState));
                if (IEEE80211_IS_CHAN_2GHZ(chan))
                        aniState->params = &ahp->ah_aniParams24;
                else
                        aniState->params = &ahp->ah_aniParams5;
                ichan->privFlags |= CHANNEL_ANI_INIT;
                HALASSERT((ichan->privFlags & CHANNEL_ANI_SETUP) == 0);
        }
        ahp->ah_curani = aniState;
#if 0
        ath_hal_printf(ah,"%s: chan %u/0x%x restore %d opmode %u%s\n",
            __func__, chan->ic_freq, chan->ic_flags, restore, opmode,
            ichan->privFlags & CHANNEL_ANI_SETUP ? " setup" : "");
#else
        HALDEBUG(ah, HAL_DEBUG_ANI, "%s: chan %u/0x%x restore %d opmode %u%s\n",
            __func__, chan->ic_freq, chan->ic_flags, restore, opmode,
            ichan->privFlags & CHANNEL_ANI_SETUP ? " setup" : "");
#endif
        OS_MARK(ah, AH_MARK_ANI_RESET, opmode);

        /*
         * Turn off PHY error frame delivery while we futz with settings.
         */
        rxfilter = ah->ah_getRxFilter(ah);
        ah->ah_setRxFilter(ah, rxfilter &~ HAL_RX_FILTER_PHYERR);

        /*
         * If ANI is disabled at this point, don't set the default
         * ANI parameter settings - leave the HAL settings there.
         * This is (currently) needed for reliable radar detection.
         */
        if (! ANI_ENA(ah)) {
                HALDEBUG(ah, HAL_DEBUG_ANI, "%s: ANI disabled\n",
                    __func__);
                goto finish;
        }

        /*
         * Use a restrictive set of ANI parameters for hostap mode.
         */
        if (opmode == HAL_M_HOSTAP) {
                if (IEEE80211_IS_CHAN_2GHZ(chan))
                        AH5416(ah)->ah_ani_function =
                            HAL_ANI_SPUR_IMMUNITY_LEVEL | HAL_ANI_FIRSTEP_LEVEL;
                else
                        AH5416(ah)->ah_ani_function = 0;
        }

        /*
         * Automatic processing is done only in station mode right now.
         */
        if (opmode == HAL_M_STA)
                ahp->ah_procPhyErr |= HAL_RSSI_ANI_ENA;
        else
                ahp->ah_procPhyErr &= ~HAL_RSSI_ANI_ENA;
        /*
         * Set all ani parameters.  We either set them to initial
         * values or restore the previous ones for the channel.
         * XXX if ANI follows hardware, we don't care what mode we're
         * XXX in, we should keep the ani parameters
         */
        if (restore && (ichan->privFlags & CHANNEL_ANI_SETUP)) {
                ar5416AniControl(ah, HAL_ANI_NOISE_IMMUNITY_LEVEL,
                                 aniState->noiseImmunityLevel);
                ar5416AniControl(ah, HAL_ANI_SPUR_IMMUNITY_LEVEL,
                                 aniState->spurImmunityLevel);
                ar5416AniControl(ah, HAL_ANI_OFDM_WEAK_SIGNAL_DETECTION,
                                 !aniState->ofdmWeakSigDetectOff);
                ar5416AniControl(ah, HAL_ANI_CCK_WEAK_SIGNAL_THR,
                                 aniState->cckWeakSigThreshold);
                ar5416AniControl(ah, HAL_ANI_FIRSTEP_LEVEL,
                                 aniState->firstepLevel);
        } else {
                ar5416AniControl(ah, HAL_ANI_NOISE_IMMUNITY_LEVEL, 0);
                ar5416AniControl(ah, HAL_ANI_SPUR_IMMUNITY_LEVEL, 0);
                ar5416AniControl(ah, HAL_ANI_OFDM_WEAK_SIGNAL_DETECTION,
                        AH_FALSE);
                ar5416AniControl(ah, HAL_ANI_CCK_WEAK_SIGNAL_THR, AH_FALSE);
                ar5416AniControl(ah, HAL_ANI_FIRSTEP_LEVEL, 0);
                ichan->privFlags |= CHANNEL_ANI_SETUP;
        }

        /*
         * In case the counters haven't yet been setup; set them up.
         */
        enableAniMIBCounters(ah, aniState->params);
        ar5416AniRestart(ah, aniState);

finish:
        /* restore RX filter mask */
        ah->ah_setRxFilter(ah, rxfilter);
}

/*
 * Process a MIB interrupt.  We may potentially be invoked because
 * any of the MIB counters overflow/trigger so don't assume we're
 * here because a PHY error counter triggered.
 */
void
ar5416ProcessMibIntr(struct ath_hal *ah, const HAL_NODE_STATS *stats)
{
        struct ath_hal_5212 *ahp = AH5212(ah);
        uint32_t phyCnt1, phyCnt2;

        HALDEBUG(ah, HAL_DEBUG_ANI, "%s: mibc 0x%x phyCnt1 0x%x phyCnt2 0x%x "
            "filtofdm 0x%x filtcck 0x%x\n",
            __func__, OS_REG_READ(ah, AR_MIBC),
            OS_REG_READ(ah, AR_PHYCNT1), OS_REG_READ(ah, AR_PHYCNT2),
            OS_REG_READ(ah, AR_FILTOFDM), OS_REG_READ(ah, AR_FILTCCK));

        /*
         * First order of business is to clear whatever caused
         * the interrupt so we don't keep getting interrupted.
         * We have the usual mib counters that are reset-on-read
         * and the additional counters that appeared starting in
         * Hainan.  We collect the mib counters and explicitly
         * zero additional counters we are not using.  Anything
         * else is reset only if it caused the interrupt.
         */
        /* NB: these are not reset-on-read */
        phyCnt1 = OS_REG_READ(ah, AR_PHY_ERR_1);
        phyCnt2 = OS_REG_READ(ah, AR_PHY_ERR_2);
        /* not used, always reset them in case they are the cause */
        OS_REG_WRITE(ah, AR_FILTOFDM, 0);
        OS_REG_WRITE(ah, AR_FILTCCK, 0);
        if ((OS_REG_READ(ah, AR_SLP_MIB_CTRL) & AR_SLP_MIB_PENDING) == 0)
                OS_REG_WRITE(ah, AR_SLP_MIB_CTRL, AR_SLP_MIB_CLEAR);

        /* Clear the mib counters and save them in the stats */
        ar5212UpdateMibCounters(ah, &ahp->ah_mibStats);
        ahp->ah_stats.ast_nodestats = *stats;

        /*
         * Check for an ani stat hitting the trigger threshold.
         * When this happens we get a MIB interrupt and the top
         * 2 bits of the counter register will be 0b11, hence
         * the mask check of phyCnt?.
         */
        if (((phyCnt1 & AR_MIBCNT_INTRMASK) == AR_MIBCNT_INTRMASK) || 
            ((phyCnt2 & AR_MIBCNT_INTRMASK) == AR_MIBCNT_INTRMASK)) {
                struct ar5212AniState *aniState = ahp->ah_curani;
                const struct ar5212AniParams *params = aniState->params;
                uint32_t ofdmPhyErrCnt, cckPhyErrCnt;

                ofdmPhyErrCnt = phyCnt1 - params->ofdmPhyErrBase;
                ahp->ah_stats.ast_ani_ofdmerrs +=
                        ofdmPhyErrCnt - aniState->ofdmPhyErrCount;
                aniState->ofdmPhyErrCount = ofdmPhyErrCnt;

                cckPhyErrCnt = phyCnt2 - params->cckPhyErrBase;
                ahp->ah_stats.ast_ani_cckerrs +=
                        cckPhyErrCnt - aniState->cckPhyErrCount;
                aniState->cckPhyErrCount = cckPhyErrCnt;

                /*
                 * NB: figure out which counter triggered.  If both
                 * trigger we'll only deal with one as the processing
                 * clobbers the error counter so the trigger threshold
                 * check will never be true.
                 */
                if (aniState->ofdmPhyErrCount > params->ofdmTrigHigh)
                        ar5416AniOfdmErrTrigger(ah);
                if (aniState->cckPhyErrCount > params->cckTrigHigh)
                        ar5416AniCckErrTrigger(ah);
                /* NB: always restart to insure the h/w counters are reset */
                ar5416AniRestart(ah, aniState);
        }
}

static void
ar5416AniLowerImmunity(struct ath_hal *ah)
{
        struct ath_hal_5212 *ahp = AH5212(ah);
        struct ar5212AniState *aniState;
        const struct ar5212AniParams *params;

        HALASSERT(ANI_ENA(ah));

        aniState = ahp->ah_curani;
        params = aniState->params;

        /*
         * In the case of AP mode operation, we cannot bucketize beacons
         * according to RSSI.  Instead, lower Firstep level, down to min, and
         * simply return.
         */
        if (AH_PRIVATE(ah)->ah_opmode == HAL_M_HOSTAP) {
                if (aniState->firstepLevel > 0) {
                        if (ar5416AniControl(ah, HAL_ANI_FIRSTEP_LEVEL,
                            aniState->firstepLevel - 1))
                                return;
                }
        }
        if (ANI_ENA_RSSI(ah)) {
                int32_t rssi = BEACON_RSSI(ahp);
                if (rssi > params->rssiThrHigh) {
                        /* 
                         * Beacon signal is high, leave ofdm weak signal
                         * detection off or it may oscillate.  Let it fall
                         * through.
                         */
                } else if (rssi > params->rssiThrLow) {
                        /*
                         * Beacon rssi in mid range, turn on ofdm weak signal
                         * detection or lower firstep level.
                         */
                        if (aniState->ofdmWeakSigDetectOff) {
                                if (ar5416AniControl(ah,
                                    HAL_ANI_OFDM_WEAK_SIGNAL_DETECTION,
                                    AH_TRUE))
                                        return;
                        }
                        if (aniState->firstepLevel > 0) {
                                if (ar5416AniControl(ah, HAL_ANI_FIRSTEP_LEVEL,
                                                 aniState->firstepLevel - 1))
                                        return;
                        }
                } else {
                        /*
                         * Beacon rssi is low, reduce firstep level.
                         */
                        if (aniState->firstepLevel > 0) {
                                if (ar5416AniControl(ah, HAL_ANI_FIRSTEP_LEVEL,
                                                 aniState->firstepLevel - 1))
                                        return;
                        }
                }
        }
        /* then lower spur immunity level, down to zero */
        if (aniState->spurImmunityLevel > 0) {
                if (ar5416AniControl(ah, HAL_ANI_SPUR_IMMUNITY_LEVEL,
                                 aniState->spurImmunityLevel - 1))
                        return;
        }
        /* 
         * if all else fails, lower noise immunity level down to a min value
         * zero for now
         */
        if (aniState->noiseImmunityLevel > 0) {
                if (ar5416AniControl(ah, HAL_ANI_NOISE_IMMUNITY_LEVEL,
                                 aniState->noiseImmunityLevel - 1))
                        return;
        }
}

#define CLOCK_RATE 44000        /* XXX use mac_usec or similar */
/* convert HW counter values to ms using 11g clock rate, goo9d enough
   for 11a and Turbo */

/* 
 * Return an approximation of the time spent ``listening'' by
 * deducting the cycles spent tx'ing and rx'ing from the total
 * cycle count since our last call.  A return value <0 indicates
 * an invalid/inconsistent time.
 *
 * This may be called with ANI disabled; in which case simply keep
 * the statistics and don't write to the aniState pointer.
 *
 * XXX TODO: Make this cleaner!
 */
static int32_t
ar5416AniGetListenTime(struct ath_hal *ah)
{
        struct ath_hal_5212 *ahp = AH5212(ah);
        struct ar5212AniState *aniState = NULL;
        int32_t listenTime = 0;
        int good;
        HAL_SURVEY_SAMPLE hs;

        /*
         * We shouldn't see ah_curchan be NULL, but just in case..
         */
        if (AH_PRIVATE(ah)->ah_curchan == AH_NULL) {
                ath_hal_printf(ah, "%s: ah_curchan = NULL?\n", __func__);
                return (0);
        }

        /*
         * Fetch the current statistics, squirrel away the current
         * sample.
         */
        OS_MEMZERO(&hs, sizeof(hs));
        good = ar5416GetMibCycleCounts(ah, &hs);
        ath_hal_survey_add_sample(ah, &hs);

        if (ANI_ENA(ah))
                aniState = ahp->ah_curani;

        if (good == AH_FALSE) {
                /*
                 * Cycle counter wrap (or initial call); it's not possible
                 * to accurately calculate a value because the registers
                 * right shift rather than wrap--so punt and return 0.
                 */
                listenTime = 0;
                ahp->ah_stats.ast_ani_lzero++;
        } else if (ANI_ENA(ah)) {
                /*
                 * Only calculate and update the cycle count if we have
                 * an ANI state.
                 */
                int32_t ccdelta =
                    AH5416(ah)->ah_cycleCount - aniState->cycleCount;
                int32_t rfdelta =
                    AH5416(ah)->ah_rxBusy - aniState->rxFrameCount;
                int32_t tfdelta =
                    AH5416(ah)->ah_txBusy - aniState->txFrameCount;
                listenTime = (ccdelta - rfdelta - tfdelta) / CLOCK_RATE;
        }

        /*
         * Again, only update ANI state if we have it.
         */
        if (ANI_ENA(ah)) {
                aniState->cycleCount = AH5416(ah)->ah_cycleCount;
                aniState->rxFrameCount = AH5416(ah)->ah_rxBusy;
                aniState->txFrameCount = AH5416(ah)->ah_txBusy;
        }

        return listenTime;
}

/*
 * Update ani stats in preparation for listen time processing.
 */
static void
updateMIBStats(struct ath_hal *ah, struct ar5212AniState *aniState)
{
        struct ath_hal_5212 *ahp = AH5212(ah);
        const struct ar5212AniParams *params = aniState->params;
        uint32_t phyCnt1, phyCnt2;
        int32_t ofdmPhyErrCnt, cckPhyErrCnt;

        /* Clear the mib counters and save them in the stats */
        ar5212UpdateMibCounters(ah, &ahp->ah_mibStats);

        /* NB: these are not reset-on-read */
        phyCnt1 = OS_REG_READ(ah, AR_PHY_ERR_1);
        phyCnt2 = OS_REG_READ(ah, AR_PHY_ERR_2);

        /* NB: these are spec'd to never roll-over */
        ofdmPhyErrCnt = phyCnt1 - params->ofdmPhyErrBase;
        if (ofdmPhyErrCnt < 0) {
                HALDEBUG(ah, HAL_DEBUG_ANI, "OFDM phyErrCnt %d phyCnt1 0x%x\n",
                    ofdmPhyErrCnt, phyCnt1);
                ofdmPhyErrCnt = AR_PHY_COUNTMAX;
        }
        ahp->ah_stats.ast_ani_ofdmerrs +=
             ofdmPhyErrCnt - aniState->ofdmPhyErrCount;
        aniState->ofdmPhyErrCount = ofdmPhyErrCnt;

        cckPhyErrCnt = phyCnt2 - params->cckPhyErrBase;
        if (cckPhyErrCnt < 0) {
                HALDEBUG(ah, HAL_DEBUG_ANI, "CCK phyErrCnt %d phyCnt2 0x%x\n",
                    cckPhyErrCnt, phyCnt2);
                cckPhyErrCnt = AR_PHY_COUNTMAX;
        }
        ahp->ah_stats.ast_ani_cckerrs +=
                cckPhyErrCnt - aniState->cckPhyErrCount;
        aniState->cckPhyErrCount = cckPhyErrCnt;
}

void
ar5416RxMonitor(struct ath_hal *ah, const HAL_NODE_STATS *stats,
                const struct ieee80211_channel *chan)
{
        struct ath_hal_5212 *ahp = AH5212(ah);
        ahp->ah_stats.ast_nodestats.ns_avgbrssi = stats->ns_avgbrssi;
}

/*
 * Do periodic processing.  This routine is called from the
 * driver's rx interrupt handler after processing frames.
 */
void
ar5416AniPoll(struct ath_hal *ah, const struct ieee80211_channel *chan)
{
        struct ath_hal_5212 *ahp = AH5212(ah);
        struct ar5212AniState *aniState = ahp->ah_curani;
        const struct ar5212AniParams *params;
        int32_t listenTime;

        /* Always update from the MIB, for statistics gathering */
        listenTime = ar5416AniGetListenTime(ah);

        /* XXX can aniState be null? */
        if (aniState == AH_NULL)
                return;

        if (!ANI_ENA(ah))
                return;

        if (listenTime < 0) {
                ahp->ah_stats.ast_ani_lneg++;
                /* restart ANI period if listenTime is invalid */
                HALDEBUG(ah, HAL_DEBUG_ANI, "%s: invalid listenTime\n",
                    __func__);
                ar5416AniRestart(ah, aniState);

                /* Don't do any further processing */
                return;
        }
        /* XXX beware of overflow? */
        aniState->listenTime += listenTime;

        OS_MARK(ah, AH_MARK_ANI_POLL, aniState->listenTime);

        params = aniState->params;
        if (aniState->listenTime > 5*params->period) {
                /* 
                 * Check to see if need to lower immunity if
                 * 5 aniPeriods have passed
                 */
                updateMIBStats(ah, aniState);
                if (aniState->ofdmPhyErrCount <= aniState->listenTime *
                    params->ofdmTrigLow/1000 &&
                    aniState->cckPhyErrCount <= aniState->listenTime *
                    params->cckTrigLow/1000)
                        ar5416AniLowerImmunity(ah);
                HALDEBUG(ah, HAL_DEBUG_ANI, "%s: lower immunity\n",
                    __func__);
                ar5416AniRestart(ah, aniState);
        } else if (aniState->listenTime > params->period) {
                updateMIBStats(ah, aniState);
                /* check to see if need to raise immunity */
                if (aniState->ofdmPhyErrCount > aniState->listenTime *
                    params->ofdmTrigHigh / 1000) {
                        HALDEBUG(ah, HAL_DEBUG_ANI,
                            "%s: OFDM err %u listenTime %u\n", __func__,
                            aniState->ofdmPhyErrCount, aniState->listenTime);
                        ar5416AniOfdmErrTrigger(ah);
                        ar5416AniRestart(ah, aniState);
                } else if (aniState->cckPhyErrCount > aniState->listenTime *
                           params->cckTrigHigh / 1000) {
                        HALDEBUG(ah, HAL_DEBUG_ANI,
                            "%s: CCK err %u listenTime %u\n", __func__,
                            aniState->cckPhyErrCount, aniState->listenTime);
                        ar5416AniCckErrTrigger(ah);
                        ar5416AniRestart(ah, aniState);
                }
        }
}