ath9k_ar9003_calib.c

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/*
 * Copyright (c) 2010-2011 Atheros Communications Inc.
 *
 * Modified for iPXE by Scott K Logan <logans@cottsay.net> July 2011
 * Original from Linux kernel 3.0.1
 *
 * 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 <ipxe/io.h>

#include "hw.h"
#include "hw-ops.h"
#include "ar9003_phy.h"

#define MAX_MEASUREMENT 8
#define MAX_MAG_DELTA   11
#define MAX_PHS_DELTA   10

struct coeff {
        int mag_coeff[AR9300_MAX_CHAINS][MAX_MEASUREMENT];
        int phs_coeff[AR9300_MAX_CHAINS][MAX_MEASUREMENT];
        int iqc_coeff[2];
};

enum ar9003_cal_types {
        IQ_MISMATCH_CAL = BIT(0),
        TEMP_COMP_CAL = BIT(1),
};

static void ar9003_hw_setup_calibration(struct ath_hw *ah,
                                        struct ath9k_cal_list *currCal)
{
        /* Select calibration to run */
        switch (currCal->calData->calType) {
        case IQ_MISMATCH_CAL:
                /*
                 * Start calibration with
                 * 2^(INIT_IQCAL_LOG_COUNT_MAX+1) samples
                 */
                REG_RMW_FIELD(ah, AR_PHY_TIMING4,
                              AR_PHY_TIMING4_IQCAL_LOG_COUNT_MAX,
                currCal->calData->calCountMax);
                REG_WRITE(ah, AR_PHY_CALMODE, AR_PHY_CALMODE_IQ);

                DBG2("ath9k: "
                        "starting IQ Mismatch Calibration\n");

                /* Kick-off cal */
                REG_SET_BIT(ah, AR_PHY_TIMING4, AR_PHY_TIMING4_DO_CAL);
                break;
        case TEMP_COMP_CAL:
                REG_RMW_FIELD(ah, AR_PHY_65NM_CH0_THERM,
                              AR_PHY_65NM_CH0_THERM_LOCAL, 1);
                REG_RMW_FIELD(ah, AR_PHY_65NM_CH0_THERM,
                              AR_PHY_65NM_CH0_THERM_START, 1);

                DBG2("ath9k: "
                        "starting Temperature Compensation Calibration\n");
                break;
        }
}

/*
 * Generic calibration routine.
 * Recalibrate the lower PHY chips to account for temperature/environment
 * changes.
 */
static int ar9003_hw_per_calibration(struct ath_hw *ah,
                                      struct ath9k_channel *ichan __unused,
                                      u8 rxchainmask,
                                      struct ath9k_cal_list *currCal)
{
        struct ath9k_hw_cal_data *caldata = ah->caldata;
        /* Cal is assumed not done until explicitly set below */
        int iscaldone = 0;

        /* Calibration in progress. */
        if (currCal->calState == CAL_RUNNING) {
                /* Check to see if it has finished. */
                if (!(REG_READ(ah, AR_PHY_TIMING4) & AR_PHY_TIMING4_DO_CAL)) {
                        /*
                        * Accumulate cal measures for active chains
                        */
                        currCal->calData->calCollect(ah);
                        ah->cal_samples++;

                        if (ah->cal_samples >=
                            currCal->calData->calNumSamples) {
                                unsigned int i, numChains = 0;
                                for (i = 0; i < AR9300_MAX_CHAINS; i++) {
                                        if (rxchainmask & (1 << i))
                                                numChains++;
                                }

                                /*
                                * Process accumulated data
                                */
                                currCal->calData->calPostProc(ah, numChains);

                                /* Calibration has finished. */
                                caldata->CalValid |= currCal->calData->calType;
                                currCal->calState = CAL_DONE;
                                iscaldone = 1;
                        } else {
                        /*
                         * Set-up collection of another sub-sample until we
                         * get desired number
                         */
                        ar9003_hw_setup_calibration(ah, currCal);
                        }
                }
        } else if (!(caldata->CalValid & currCal->calData->calType)) {
                /* If current cal is marked invalid in channel, kick it off */
                ath9k_hw_reset_calibration(ah, currCal);
        }

        return iscaldone;
}

static int ar9003_hw_calibrate(struct ath_hw *ah,
                                struct ath9k_channel *chan,
                                u8 rxchainmask,
                                int longcal)
{
        int iscaldone = 1;
        struct ath9k_cal_list *currCal = ah->cal_list_curr;

        /*
         * For given calibration:
         * 1. Call generic cal routine
         * 2. When this cal is done (isCalDone) if we have more cals waiting
         *    (eg after reset), mask this to upper layers by not propagating
         *    isCalDone if it is set to TRUE.
         *    Instead, change isCalDone to FALSE and setup the waiting cal(s)
         *    to be run.
         */
        if (currCal &&
            (currCal->calState == CAL_RUNNING ||
             currCal->calState == CAL_WAITING)) {
                iscaldone = ar9003_hw_per_calibration(ah, chan,
                                                      rxchainmask, currCal);
                if (iscaldone) {
                        ah->cal_list_curr = currCal = currCal->calNext;

                        if (currCal->calState == CAL_WAITING) {
                                iscaldone = 0;
                                ath9k_hw_reset_calibration(ah, currCal);
                        }
                }
        }

        /* Do NF cal only at longer intervals */
        if (longcal) {
                /*
                 * Get the value from the previous NF cal and update
                 * history buffer.
                 */
                ath9k_hw_getnf(ah, chan);

                /*
                 * Load the NF from history buffer of the current channel.
                 * NF is slow time-variant, so it is OK to use a historical
                 * value.
                 */
                ath9k_hw_loadnf(ah, ah->curchan);

                /* start NF calibration, without updating BB NF register */
                ath9k_hw_start_nfcal(ah, 0);
        }

        return iscaldone;
}

static void ar9003_hw_iqcal_collect(struct ath_hw *ah)
{
        int i;

        /* Accumulate IQ cal measures for active chains */
        for (i = 0; i < AR5416_MAX_CHAINS; i++) {
                if (ah->txchainmask & BIT(i)) {
                        ah->totalPowerMeasI[i] +=
                                REG_READ(ah, AR_PHY_CAL_MEAS_0(i));
                        ah->totalPowerMeasQ[i] +=
                                REG_READ(ah, AR_PHY_CAL_MEAS_1(i));
                        ah->totalIqCorrMeas[i] +=
                                (int32_t) REG_READ(ah, AR_PHY_CAL_MEAS_2(i));
                        DBG2("ath9k: "
                                "%d: Chn %d pmi=0x%08x;pmq=0x%08x;iqcm=0x%08x;\n",
                                ah->cal_samples, i, ah->totalPowerMeasI[i],
                                ah->totalPowerMeasQ[i],
                                ah->totalIqCorrMeas[i]);
                }
        }
}

static void ar9003_hw_iqcalibrate(struct ath_hw *ah, u8 numChains)
{
        u32 powerMeasQ, powerMeasI, iqCorrMeas;
        u32 qCoffDenom, iCoffDenom;
        int32_t qCoff, iCoff;
        int iqCorrNeg, i;
        static const uint32_t offset_array[3] = {
                AR_PHY_RX_IQCAL_CORR_B0,
                AR_PHY_RX_IQCAL_CORR_B1,
                AR_PHY_RX_IQCAL_CORR_B2,
        };

        for (i = 0; i < numChains; i++) {
                powerMeasI = ah->totalPowerMeasI[i];
                powerMeasQ = ah->totalPowerMeasQ[i];
                iqCorrMeas = ah->totalIqCorrMeas[i];

                DBG2("ath9k: "
                        "Starting IQ Cal and Correction for Chain %d\n",
                        i);

                DBG2("ath9k: "
                        "Orignal: Chn %diq_corr_meas = 0x%08x\n",
                        i, ah->totalIqCorrMeas[i]);

                iqCorrNeg = 0;

                if (iqCorrMeas > 0x80000000) {
                        iqCorrMeas = (0xffffffff - iqCorrMeas) + 1;
                        iqCorrNeg = 1;
                }

                DBG2("ath9k: "
                        "Chn %d pwr_meas_i = 0x%08x\n", i, powerMeasI);
                DBG2("ath9k: "
                        "Chn %d pwr_meas_q = 0x%08x\n", i, powerMeasQ);
                DBG2("ath9k: iqCorrNeg is 0x%08x\n",
                        iqCorrNeg);

                iCoffDenom = (powerMeasI / 2 + powerMeasQ / 2) / 256;
                qCoffDenom = powerMeasQ / 64;

                if ((iCoffDenom != 0) && (qCoffDenom != 0)) {
                        iCoff = iqCorrMeas / iCoffDenom;
                        qCoff = powerMeasI / qCoffDenom - 64;
                        DBG2("ath9k: "
                                "Chn %d iCoff = 0x%08x\n", i, iCoff);
                        DBG2("ath9k: "
                                "Chn %d qCoff = 0x%08x\n", i, qCoff);

                        /* Force bounds on iCoff */
                        if (iCoff >= 63)
                                iCoff = 63;
                        else if (iCoff <= -63)
                                iCoff = -63;

                        /* Negate iCoff if iqCorrNeg == 0 */
                        if (iqCorrNeg == 0x0)
                                iCoff = -iCoff;

                        /* Force bounds on qCoff */
                        if (qCoff >= 63)
                                qCoff = 63;
                        else if (qCoff <= -63)
                                qCoff = -63;

                        iCoff = iCoff & 0x7f;
                        qCoff = qCoff & 0x7f;

                        DBG2("ath9k: "
                                "Chn %d : iCoff = 0x%x  qCoff = 0x%x\n",
                                i, iCoff, qCoff);
                        DBG2("ath9k: "
                                "Register offset (0x%04x) before update = 0x%x\n",
                                offset_array[i],
                                REG_READ(ah, offset_array[i]));

                        REG_RMW_FIELD(ah, offset_array[i],
                                      AR_PHY_RX_IQCAL_CORR_IQCORR_Q_I_COFF,
                                      iCoff);
                        REG_RMW_FIELD(ah, offset_array[i],
                                      AR_PHY_RX_IQCAL_CORR_IQCORR_Q_Q_COFF,
                                      qCoff);
                        DBG2("ath9k: "
                                "Register offset (0x%04x) QI COFF (bitfields 0x%08x) after update = 0x%x\n",
                                offset_array[i],
                                AR_PHY_RX_IQCAL_CORR_IQCORR_Q_I_COFF,
                                REG_READ(ah, offset_array[i]));
                        DBG2("ath9k: "
                                "Register offset (0x%04x) QQ COFF (bitfields 0x%08x) after update = 0x%x\n",
                                offset_array[i],
                                AR_PHY_RX_IQCAL_CORR_IQCORR_Q_Q_COFF,
                                REG_READ(ah, offset_array[i]));

                        DBG2("ath9k: "
                                "IQ Cal and Correction done for Chain %d\n", i);
                }
        }

        REG_SET_BIT(ah, AR_PHY_RX_IQCAL_CORR_B0,
                    AR_PHY_RX_IQCAL_CORR_IQCORR_ENABLE);
        DBG2("ath9k: "
                "IQ Cal and Correction (offset 0x%04x) enabled (bit position 0x%08x). New Value 0x%08x\n",
                (unsigned) (AR_PHY_RX_IQCAL_CORR_B0),
                AR_PHY_RX_IQCAL_CORR_IQCORR_ENABLE,
                REG_READ(ah, AR_PHY_RX_IQCAL_CORR_B0));
}

static const struct ath9k_percal_data iq_cal_single_sample = {
        IQ_MISMATCH_CAL,
        MIN_CAL_SAMPLES,
        PER_MAX_LOG_COUNT,
        ar9003_hw_iqcal_collect,
        ar9003_hw_iqcalibrate
};

static void ar9003_hw_init_cal_settings(struct ath_hw *ah)
{
        ah->iq_caldata.calData = &iq_cal_single_sample;
}

/*
 * solve 4x4 linear equation used in loopback iq cal.
 */
static int ar9003_hw_solve_iq_cal(struct ath_hw *ah __unused,
                                   s32 sin_2phi_1,
                                   s32 cos_2phi_1,
                                   s32 sin_2phi_2,
                                   s32 cos_2phi_2,
                                   s32 mag_a0_d0,
                                   s32 phs_a0_d0,
                                   s32 mag_a1_d0,
                                   s32 phs_a1_d0,
                                   s32 solved_eq[])
{
        s32 f1 = cos_2phi_1 - cos_2phi_2,
            f3 = sin_2phi_1 - sin_2phi_2,
            f2;
        s32 mag_tx, phs_tx, mag_rx, phs_rx;
        const s32 result_shift = 1 << 15;

        f2 = (f1 * f1 + f3 * f3) / result_shift;

        if (!f2) {
                DBG("ath9k: Divide by 0\n");
                return 0;
        }

        /* mag mismatch, tx */
        mag_tx = f1 * (mag_a0_d0  - mag_a1_d0) + f3 * (phs_a0_d0 - phs_a1_d0);
        /* phs mismatch, tx */
        phs_tx = f3 * (-mag_a0_d0 + mag_a1_d0) + f1 * (phs_a0_d0 - phs_a1_d0);

        mag_tx = (mag_tx / f2);
        phs_tx = (phs_tx / f2);

        /* mag mismatch, rx */
        mag_rx = mag_a0_d0 - (cos_2phi_1 * mag_tx + sin_2phi_1 * phs_tx) /
                 result_shift;
        /* phs mismatch, rx */
        phs_rx = phs_a0_d0 + (sin_2phi_1 * mag_tx - cos_2phi_1 * phs_tx) /
                 result_shift;

        solved_eq[0] = mag_tx;
        solved_eq[1] = phs_tx;
        solved_eq[2] = mag_rx;
        solved_eq[3] = phs_rx;

        return 1;
}

static s32 ar9003_hw_find_mag_approx(struct ath_hw *ah __unused, s32 in_re, s32 in_im)
{
        s32 abs_i = abs(in_re),
            abs_q = abs(in_im),
            max_abs, min_abs;

        if (abs_i > abs_q) {
                max_abs = abs_i;
                min_abs = abs_q;
        } else {
                max_abs = abs_q;
                min_abs = abs_i;
        }

        return max_abs - (max_abs / 32) + (min_abs / 8) + (min_abs / 4);
}

#define DELPT 32

static int ar9003_hw_calc_iq_corr(struct ath_hw *ah,
                                   s32 chain_idx,
                                   const s32 iq_res[],
                                   s32 iqc_coeff[])
{
        s32 i2_m_q2_a0_d0, i2_p_q2_a0_d0, iq_corr_a0_d0,
            i2_m_q2_a0_d1, i2_p_q2_a0_d1, iq_corr_a0_d1,
            i2_m_q2_a1_d0, i2_p_q2_a1_d0, iq_corr_a1_d0,
            i2_m_q2_a1_d1, i2_p_q2_a1_d1, iq_corr_a1_d1;
        s32 mag_a0_d0, mag_a1_d0, mag_a0_d1, mag_a1_d1,
            phs_a0_d0, phs_a1_d0, phs_a0_d1, phs_a1_d1,
            sin_2phi_1, cos_2phi_1,
            sin_2phi_2, cos_2phi_2;
        s32 mag_tx, phs_tx, mag_rx, phs_rx;
        s32 solved_eq[4], mag_corr_tx, phs_corr_tx, mag_corr_rx, phs_corr_rx,
            q_q_coff, q_i_coff;
        const s32 res_scale = 1 << 15;
        const s32 delpt_shift = 1 << 8;
        s32 mag1, mag2;

        i2_m_q2_a0_d0 = iq_res[0] & 0xfff;
        i2_p_q2_a0_d0 = (iq_res[0] >> 12) & 0xfff;
        iq_corr_a0_d0 = ((iq_res[0] >> 24) & 0xff) + ((iq_res[1] & 0xf) << 8);

        if (i2_m_q2_a0_d0 > 0x800)
                i2_m_q2_a0_d0 = -((0xfff - i2_m_q2_a0_d0) + 1);

        if (i2_p_q2_a0_d0 > 0x800)
                i2_p_q2_a0_d0 = -((0xfff - i2_p_q2_a0_d0) + 1);

        if (iq_corr_a0_d0 > 0x800)
                iq_corr_a0_d0 = -((0xfff - iq_corr_a0_d0) + 1);

        i2_m_q2_a0_d1 = (iq_res[1] >> 4) & 0xfff;
        i2_p_q2_a0_d1 = (iq_res[2] & 0xfff);
        iq_corr_a0_d1 = (iq_res[2] >> 12) & 0xfff;

        if (i2_m_q2_a0_d1 > 0x800)
                i2_m_q2_a0_d1 = -((0xfff - i2_m_q2_a0_d1) + 1);

        if (i2_p_q2_a0_d1 > 0x800)
                i2_p_q2_a0_d1 = -((0xfff - i2_p_q2_a0_d1) + 1);

        if (iq_corr_a0_d1 > 0x800)
                iq_corr_a0_d1 = -((0xfff - iq_corr_a0_d1) + 1);

        i2_m_q2_a1_d0 = ((iq_res[2] >> 24) & 0xff) + ((iq_res[3] & 0xf) << 8);
        i2_p_q2_a1_d0 = (iq_res[3] >> 4) & 0xfff;
        iq_corr_a1_d0 = iq_res[4] & 0xfff;

        if (i2_m_q2_a1_d0 > 0x800)
                i2_m_q2_a1_d0 = -((0xfff - i2_m_q2_a1_d0) + 1);

        if (i2_p_q2_a1_d0 > 0x800)
                i2_p_q2_a1_d0 = -((0xfff - i2_p_q2_a1_d0) + 1);

        if (iq_corr_a1_d0 > 0x800)
                iq_corr_a1_d0 = -((0xfff - iq_corr_a1_d0) + 1);

        i2_m_q2_a1_d1 = (iq_res[4] >> 12) & 0xfff;
        i2_p_q2_a1_d1 = ((iq_res[4] >> 24) & 0xff) + ((iq_res[5] & 0xf) << 8);
        iq_corr_a1_d1 = (iq_res[5] >> 4) & 0xfff;

        if (i2_m_q2_a1_d1 > 0x800)
                i2_m_q2_a1_d1 = -((0xfff - i2_m_q2_a1_d1) + 1);

        if (i2_p_q2_a1_d1 > 0x800)
                i2_p_q2_a1_d1 = -((0xfff - i2_p_q2_a1_d1) + 1);

        if (iq_corr_a1_d1 > 0x800)
                iq_corr_a1_d1 = -((0xfff - iq_corr_a1_d1) + 1);

        if ((i2_p_q2_a0_d0 == 0) || (i2_p_q2_a0_d1 == 0) ||
            (i2_p_q2_a1_d0 == 0) || (i2_p_q2_a1_d1 == 0)) {
                DBG("ath9k: "
                        "Divide by 0:\n"
                        "a0_d0=%d\n"
                        "a0_d1=%d\n"
                        "a2_d0=%d\n"
                        "a1_d1=%d\n",
                        i2_p_q2_a0_d0, i2_p_q2_a0_d1,
                        i2_p_q2_a1_d0, i2_p_q2_a1_d1);
                return 0;
        }

        mag_a0_d0 = (i2_m_q2_a0_d0 * res_scale) / i2_p_q2_a0_d0;
        phs_a0_d0 = (iq_corr_a0_d0 * res_scale) / i2_p_q2_a0_d0;

        mag_a0_d1 = (i2_m_q2_a0_d1 * res_scale) / i2_p_q2_a0_d1;
        phs_a0_d1 = (iq_corr_a0_d1 * res_scale) / i2_p_q2_a0_d1;

        mag_a1_d0 = (i2_m_q2_a1_d0 * res_scale) / i2_p_q2_a1_d0;
        phs_a1_d0 = (iq_corr_a1_d0 * res_scale) / i2_p_q2_a1_d0;

        mag_a1_d1 = (i2_m_q2_a1_d1 * res_scale) / i2_p_q2_a1_d1;
        phs_a1_d1 = (iq_corr_a1_d1 * res_scale) / i2_p_q2_a1_d1;

        /* w/o analog phase shift */
        sin_2phi_1 = (((mag_a0_d0 - mag_a0_d1) * delpt_shift) / DELPT);
        /* w/o analog phase shift */
        cos_2phi_1 = (((phs_a0_d1 - phs_a0_d0) * delpt_shift) / DELPT);
        /* w/  analog phase shift */
        sin_2phi_2 = (((mag_a1_d0 - mag_a1_d1) * delpt_shift) / DELPT);
        /* w/  analog phase shift */
        cos_2phi_2 = (((phs_a1_d1 - phs_a1_d0) * delpt_shift) / DELPT);

        /*
         * force sin^2 + cos^2 = 1;
         * find magnitude by approximation
         */
        mag1 = ar9003_hw_find_mag_approx(ah, cos_2phi_1, sin_2phi_1);
        mag2 = ar9003_hw_find_mag_approx(ah, cos_2phi_2, sin_2phi_2);

        if ((mag1 == 0) || (mag2 == 0)) {
                DBG("ath9k: "
                        "Divide by 0: mag1=%d, mag2=%d\n",
                        mag1, mag2);
                return 0;
        }

        /* normalization sin and cos by mag */
        sin_2phi_1 = (sin_2phi_1 * res_scale / mag1);
        cos_2phi_1 = (cos_2phi_1 * res_scale / mag1);
        sin_2phi_2 = (sin_2phi_2 * res_scale / mag2);
        cos_2phi_2 = (cos_2phi_2 * res_scale / mag2);

        /* calculate IQ mismatch */
        if (!ar9003_hw_solve_iq_cal(ah,
                             sin_2phi_1, cos_2phi_1,
                             sin_2phi_2, cos_2phi_2,
                             mag_a0_d0, phs_a0_d0,
                             mag_a1_d0,
                             phs_a1_d0, solved_eq)) {
                DBG("ath9k: "
                        "Call to ar9003_hw_solve_iq_cal() failed.\n");
                return 0;
        }

        mag_tx = solved_eq[0];
        phs_tx = solved_eq[1];
        mag_rx = solved_eq[2];
        phs_rx = solved_eq[3];

        DBG2("ath9k: "
                "chain %d: mag mismatch=%d phase mismatch=%d\n",
                chain_idx, mag_tx/res_scale, phs_tx/res_scale);

        if (res_scale == mag_tx) {
                DBG("ath9k: "
                        "Divide by 0: mag_tx=%d, res_scale=%d\n",
                        mag_tx, res_scale);
                return 0;
        }

        /* calculate and quantize Tx IQ correction factor */
        mag_corr_tx = (mag_tx * res_scale) / (res_scale - mag_tx);
        phs_corr_tx = -phs_tx;

        q_q_coff = (mag_corr_tx * 128 / res_scale);
        q_i_coff = (phs_corr_tx * 256 / res_scale);

        DBG2("ath9k: "
                "tx chain %d: mag corr=%d  phase corr=%d\n",
                chain_idx, q_q_coff, q_i_coff);

        if (q_i_coff < -63)
                q_i_coff = -63;
        if (q_i_coff > 63)
                q_i_coff = 63;
        if (q_q_coff < -63)
                q_q_coff = -63;
        if (q_q_coff > 63)
                q_q_coff = 63;

        iqc_coeff[0] = (q_q_coff * 128) + q_i_coff;

        DBG2("ath9k: "
                "tx chain %d: iq corr coeff=%x\n",
                chain_idx, iqc_coeff[0]);

        if (-mag_rx == res_scale) {
                DBG("ath9k: "
                        "Divide by 0: mag_rx=%d, res_scale=%d\n",
                        mag_rx, res_scale);
                return 0;
        }

        /* calculate and quantize Rx IQ correction factors */
        mag_corr_rx = (-mag_rx * res_scale) / (res_scale + mag_rx);
        phs_corr_rx = -phs_rx;

        q_q_coff = (mag_corr_rx * 128 / res_scale);
        q_i_coff = (phs_corr_rx * 256 / res_scale);

        DBG("ath9k: "
                "rx chain %d: mag corr=%d  phase corr=%d\n",
                chain_idx, q_q_coff, q_i_coff);

        if (q_i_coff < -63)
                q_i_coff = -63;
        if (q_i_coff > 63)
                q_i_coff = 63;
        if (q_q_coff < -63)
                q_q_coff = -63;
        if (q_q_coff > 63)
                q_q_coff = 63;

        iqc_coeff[1] = (q_q_coff * 128) + q_i_coff;

        DBG2("ath9k: "
                "rx chain %d: iq corr coeff=%x\n",
                chain_idx, iqc_coeff[1]);

        return 1;
}

static void ar9003_hw_detect_outlier(int *mp_coeff, int nmeasurement,
                                     int max_delta)
{
        int mp_max = -64, max_idx = 0;
        int mp_min = 63, min_idx = 0;
        int mp_avg = 0, i, outlier_idx = 0;

        /* find min/max mismatch across all calibrated gains */
        for (i = 0; i < nmeasurement; i++) {
                mp_avg += mp_coeff[i];
                if (mp_coeff[i] > mp_max) {
                        mp_max = mp_coeff[i];
                        max_idx = i;
                } else if (mp_coeff[i] < mp_min) {
                        mp_min = mp_coeff[i];
                        min_idx = i;
                }
        }

        /* find average (exclude max abs value) */
        for (i = 0; i < nmeasurement; i++) {
                if ((abs(mp_coeff[i]) < abs(mp_max)) ||
                    (abs(mp_coeff[i]) < abs(mp_min)))
                        mp_avg += mp_coeff[i];
        }
        mp_avg /= (nmeasurement - 1);

        /* detect outlier */
        if (abs(mp_max - mp_min) > max_delta) {
                if (abs(mp_max - mp_avg) > abs(mp_min - mp_avg))
                        outlier_idx = max_idx;
                else
                        outlier_idx = min_idx;
        }
        mp_coeff[outlier_idx] = mp_avg;
}

static void ar9003_hw_tx_iqcal_load_avg_2_passes(struct ath_hw *ah,
                                                 u8 num_chains,
                                                 struct coeff *coeff)
{
        int i, im, nmeasurement;
        u32 tx_corr_coeff[MAX_MEASUREMENT][AR9300_MAX_CHAINS];

        memset(tx_corr_coeff, 0, sizeof(tx_corr_coeff));
        for (i = 0; i < MAX_MEASUREMENT / 2; i++) {
                tx_corr_coeff[i * 2][0] = tx_corr_coeff[(i * 2) + 1][0] =
                                        AR_PHY_TX_IQCAL_CORR_COEFF_B0(i);
                if (!AR_SREV_9485(ah)) {
                        tx_corr_coeff[i * 2][1] =
                        tx_corr_coeff[(i * 2) + 1][1] =
                                        AR_PHY_TX_IQCAL_CORR_COEFF_B1(i);

                        tx_corr_coeff[i * 2][2] =
                        tx_corr_coeff[(i * 2) + 1][2] =
                                        AR_PHY_TX_IQCAL_CORR_COEFF_B2(i);
                }
        }

        /* Load the average of 2 passes */
        for (i = 0; i < num_chains; i++) {
                nmeasurement = REG_READ_FIELD(ah,
                                AR_PHY_TX_IQCAL_STATUS_B0,
                                AR_PHY_CALIBRATED_GAINS_0);

                if (nmeasurement > MAX_MEASUREMENT)
                        nmeasurement = MAX_MEASUREMENT;

                /* detect outlier only if nmeasurement > 1 */
                if (nmeasurement > 1) {
                        /* Detect magnitude outlier */
                        ar9003_hw_detect_outlier(coeff->mag_coeff[i],
                                        nmeasurement, MAX_MAG_DELTA);

                        /* Detect phase outlier */
                        ar9003_hw_detect_outlier(coeff->phs_coeff[i],
                                        nmeasurement, MAX_PHS_DELTA);
                }

                for (im = 0; im < nmeasurement; im++) {

                        coeff->iqc_coeff[0] = (coeff->mag_coeff[i][im] & 0x7f) |
                                ((coeff->phs_coeff[i][im] & 0x7f) << 7);

                        if ((im % 2) == 0)
                                REG_RMW_FIELD(ah, tx_corr_coeff[im][i],
                                        AR_PHY_TX_IQCAL_CORR_COEFF_00_COEFF_TABLE,
                                        coeff->iqc_coeff[0]);
                        else
                                REG_RMW_FIELD(ah, tx_corr_coeff[im][i],
                                        AR_PHY_TX_IQCAL_CORR_COEFF_01_COEFF_TABLE,
                                        coeff->iqc_coeff[0]);
                }
        }

        REG_RMW_FIELD(ah, AR_PHY_TX_IQCAL_CONTROL_3,
                      AR_PHY_TX_IQCAL_CONTROL_3_IQCORR_EN, 0x1);
        REG_RMW_FIELD(ah, AR_PHY_RX_IQCAL_CORR_B0,
                      AR_PHY_RX_IQCAL_CORR_B0_LOOPBACK_IQCORR_EN, 0x1);

        return;

}

static int ar9003_hw_tx_iq_cal_run(struct ath_hw *ah)
{
        u8 tx_gain_forced;

        tx_gain_forced = REG_READ_FIELD(ah, AR_PHY_TX_FORCED_GAIN,
                                        AR_PHY_TXGAIN_FORCE);
        if (tx_gain_forced)
                REG_RMW_FIELD(ah, AR_PHY_TX_FORCED_GAIN,
                              AR_PHY_TXGAIN_FORCE, 0);

        REG_RMW_FIELD(ah, AR_PHY_TX_IQCAL_START,
                      AR_PHY_TX_IQCAL_START_DO_CAL, 1);

        if (!ath9k_hw_wait(ah, AR_PHY_TX_IQCAL_START,
                        AR_PHY_TX_IQCAL_START_DO_CAL, 0,
                        AH_WAIT_TIMEOUT)) {
                DBG2("ath9k: "
                        "Tx IQ Cal is not completed.\n");
                return 0;
        }
        return 1;
}

static void ar9003_hw_tx_iq_cal_post_proc(struct ath_hw *ah)
{
        const u32 txiqcal_status[AR9300_MAX_CHAINS] = {
                AR_PHY_TX_IQCAL_STATUS_B0,
                AR_PHY_TX_IQCAL_STATUS_B1,
                AR_PHY_TX_IQCAL_STATUS_B2,
        };
        const uint32_t chan_info_tab[] = {
                AR_PHY_CHAN_INFO_TAB_0,
                AR_PHY_CHAN_INFO_TAB_1,
                AR_PHY_CHAN_INFO_TAB_2,
        };
        struct coeff coeff;
        s32 iq_res[6];
        u8 num_chains = 0;
        int i, im, j;
        int nmeasurement;

        for (i = 0; i < AR9300_MAX_CHAINS; i++) {
                if (ah->txchainmask & (1 << i))
                        num_chains++;
        }

        for (i = 0; i < num_chains; i++) {
                nmeasurement = REG_READ_FIELD(ah,
                                AR_PHY_TX_IQCAL_STATUS_B0,
                                AR_PHY_CALIBRATED_GAINS_0);
                if (nmeasurement > MAX_MEASUREMENT)
                        nmeasurement = MAX_MEASUREMENT;

                for (im = 0; im < nmeasurement; im++) {
                        DBG2("ath9k: "
                                "Doing Tx IQ Cal for chain %d.\n", i);

                        if (REG_READ(ah, txiqcal_status[i]) &
                                        AR_PHY_TX_IQCAL_STATUS_FAILED) {
                                DBG("ath9k: "
                                        "Tx IQ Cal failed for chain %d.\n", i);
                                goto tx_iqcal_fail;
                        }

                        for (j = 0; j < 3; j++) {
                                u32 idx = 2 * j, offset = 4 * (3 * im + j);

                                REG_RMW_FIELD(ah,
                                                AR_PHY_CHAN_INFO_MEMORY,
                                                AR_PHY_CHAN_INFO_TAB_S2_READ,
                                                0);

                                /* 32 bits */
                                iq_res[idx] = REG_READ(ah,
                                                chan_info_tab[i] +
                                                offset);

                                REG_RMW_FIELD(ah,
                                                AR_PHY_CHAN_INFO_MEMORY,
                                                AR_PHY_CHAN_INFO_TAB_S2_READ,
                                                1);

                                /* 16 bits */
                                iq_res[idx + 1] = 0xffff & REG_READ(ah,
                                                chan_info_tab[i] + offset);

                                DBG2("ath9k: "
                                        "IQ RES[%d]=0x%x"
                                        "IQ_RES[%d]=0x%x\n",
                                        idx, iq_res[idx], idx + 1,
                                        iq_res[idx + 1]);
                        }

                        if (!ar9003_hw_calc_iq_corr(ah, i, iq_res,
                                                coeff.iqc_coeff)) {
                                DBG("ath9k: "
                                        "Failed in calculation of \
                                        IQ correction.\n");
                                goto tx_iqcal_fail;
                        }

                        coeff.mag_coeff[i][im] = coeff.iqc_coeff[0] & 0x7f;
                        coeff.phs_coeff[i][im] =
                                (coeff.iqc_coeff[0] >> 7) & 0x7f;

                        if (coeff.mag_coeff[i][im] > 63)
                                coeff.mag_coeff[i][im] -= 128;
                        if (coeff.phs_coeff[i][im] > 63)
                                coeff.phs_coeff[i][im] -= 128;
                }
        }
        ar9003_hw_tx_iqcal_load_avg_2_passes(ah, num_chains, &coeff);

        return;

tx_iqcal_fail:
        DBG("ath9k: Tx IQ Cal failed\n");
        return;
}
static int ar9003_hw_init_cal(struct ath_hw *ah,
                               struct ath9k_channel *chan __unused)
{
        struct ath9k_hw_capabilities *pCap = &ah->caps;
        int val;
        int txiqcal_done = 0;

        val = REG_READ(ah, AR_ENT_OTP);
        DBG2("ath9k: ath9k: AR_ENT_OTP 0x%x\n", val);

        /* Configure rx/tx chains before running AGC/TxiQ cals */
        if (val & AR_ENT_OTP_CHAIN2_DISABLE)
                ar9003_hw_set_chain_masks(ah, 0x3, 0x3);
        else
                ar9003_hw_set_chain_masks(ah, pCap->rx_chainmask,
                                          pCap->tx_chainmask);

        /* Do Tx IQ Calibration */
        REG_RMW_FIELD(ah, AR_PHY_TX_IQCAL_CONTROL_1,
                      AR_PHY_TX_IQCAL_CONTROL_1_IQCORR_I_Q_COFF_DELPT,
                      DELPT);

        /*
         * For AR9485 or later chips, TxIQ cal runs as part of
         * AGC calibration
         */
        if (AR_SREV_9485_OR_LATER(ah))
                txiqcal_done = 1;
        else {
                txiqcal_done = ar9003_hw_tx_iq_cal_run(ah);
                REG_WRITE(ah, AR_PHY_ACTIVE, AR_PHY_ACTIVE_DIS);
                udelay(5);
                REG_WRITE(ah, AR_PHY_ACTIVE, AR_PHY_ACTIVE_EN);
        }

        /* Calibrate the AGC */
        REG_WRITE(ah, AR_PHY_AGC_CONTROL,
                  REG_READ(ah, AR_PHY_AGC_CONTROL) |
                  AR_PHY_AGC_CONTROL_CAL);

        /* Poll for offset calibration complete */
        if (!ath9k_hw_wait(ah, AR_PHY_AGC_CONTROL, AR_PHY_AGC_CONTROL_CAL,
                           0, AH_WAIT_TIMEOUT)) {
                DBG("ath9k: "
                        "offset calibration failed to complete in 1ms; noisy environment?\n");
                return 0;
        }

        if (txiqcal_done)
                ar9003_hw_tx_iq_cal_post_proc(ah);

        /* Revert chainmasks to their original values before NF cal */
        ar9003_hw_set_chain_masks(ah, ah->rxchainmask, ah->txchainmask);

        ath9k_hw_start_nfcal(ah, 1);

        /* Initialize list pointers */
        ah->cal_list = ah->cal_list_last = ah->cal_list_curr = NULL;
        ah->supp_cals = IQ_MISMATCH_CAL;

        if (ah->supp_cals & IQ_MISMATCH_CAL) {
                INIT_CAL(&ah->iq_caldata);
                INSERT_CAL(ah, &ah->iq_caldata);
                DBG2("ath9k: "
                        "enabling IQ Calibration.\n");
        }

        if (ah->supp_cals & TEMP_COMP_CAL) {
                INIT_CAL(&ah->tempCompCalData);
                INSERT_CAL(ah, &ah->tempCompCalData);
                DBG2("ath9k: "
                        "enabling Temperature Compensation Calibration.\n");
        }

        /* Initialize current pointer to first element in list */
        ah->cal_list_curr = ah->cal_list;

        if (ah->cal_list_curr)
                ath9k_hw_reset_calibration(ah, ah->cal_list_curr);

        if (ah->caldata)
                ah->caldata->CalValid = 0;

        return 1;
}

void ar9003_hw_attach_calib_ops(struct ath_hw *ah)
{
        struct ath_hw_private_ops *priv_ops = ath9k_hw_private_ops(ah);
        struct ath_hw_ops *ops = ath9k_hw_ops(ah);

        priv_ops->init_cal_settings = ar9003_hw_init_cal_settings;
        priv_ops->init_cal = ar9003_hw_init_cal;
        priv_ops->setup_calibration = ar9003_hw_setup_calibration;

        ops->calibrate = ar9003_hw_calibrate;
}