ar5416_cal_iq.c

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/*-
 * SPDX-License-Identifier: ISC
 *
 * Copyright (c) 2002-2008 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.
 *
 * $FreeBSD$
 */
#include "opt_ah.h"
 
#include "ah.h"
#include "ah_internal.h"
#include "ah_devid.h"
 
#include "ar5416/ar5416.h"
#include "ar5416/ar5416reg.h"
#include "ar5416/ar5416phy.h"
 
/* IQ Cal aliases */
#define totalPowerMeasI(i)      caldata[0][i].u
#define totalPowerMeasQ(i)      caldata[1][i].u
#define totalIqCorrMeas(i)      caldata[2][i].s
 
/*
 * Collect data from HW to later perform IQ Mismatch Calibration
 */
void
ar5416IQCalCollect(struct ath_hal *ah)
{
        struct ar5416PerCal *cal = &AH5416(ah)->ah_cal;
        int i;
 
        /* 
         * Accumulate IQ cal measures for active chains
         */
        for (i = 0; i < AR5416_MAX_CHAINS; i++) {
                cal->totalPowerMeasI(i) +=
                    OS_REG_READ(ah, AR_PHY_CAL_MEAS_0(i));
                cal->totalPowerMeasQ(i) +=
                    OS_REG_READ(ah, AR_PHY_CAL_MEAS_1(i));
                cal->totalIqCorrMeas(i) += (int32_t)
                    OS_REG_READ(ah, AR_PHY_CAL_MEAS_2(i));
                HALDEBUG(ah, HAL_DEBUG_PERCAL,
                    "%d: Chn %d pmi=0x%08x;pmq=0x%08x;iqcm=0x%08x;\n",
                    cal->calSamples, i, cal->totalPowerMeasI(i),
                    cal->totalPowerMeasQ(i), cal->totalIqCorrMeas(i));
        }
}
 
/*
 * Use HW data to do IQ Mismatch Calibration
 */
void
ar5416IQCalibration(struct ath_hal *ah, uint8_t numChains)
{
        struct ar5416PerCal *cal = &AH5416(ah)->ah_cal;
        int i;
 
        for (i = 0; i < numChains; i++) {
                uint32_t powerMeasI = cal->totalPowerMeasI(i);
                uint32_t powerMeasQ = cal->totalPowerMeasQ(i);
                uint32_t iqCorrMeas = cal->totalIqCorrMeas(i);
                uint32_t qCoffDenom, iCoffDenom;
                int iqCorrNeg;
 
                HALDEBUG(ah, HAL_DEBUG_PERCAL,
                    "Start IQ Cal and Correction for Chain %d\n", i);
                HALDEBUG(ah, HAL_DEBUG_PERCAL,
                    "Orignal: iq_corr_meas = 0x%08x\n", iqCorrMeas);
 
                iqCorrNeg = 0;
                /* iqCorrMeas is always negative. */ 
                if (iqCorrMeas > 0x80000000)  {
                        iqCorrMeas = (0xffffffff - iqCorrMeas) + 1;
                        iqCorrNeg = 1;
                }
 
                HALDEBUG(ah, HAL_DEBUG_PERCAL, " pwr_meas_i = 0x%08x\n",
                    powerMeasI);
                HALDEBUG(ah, HAL_DEBUG_PERCAL, " pwr_meas_q = 0x%08x\n",
                    powerMeasQ);
                HALDEBUG(ah, HAL_DEBUG_PERCAL, " iqCorrNeg is 0x%08x\n",
                    iqCorrNeg);
 
                iCoffDenom = (powerMeasI/2 + powerMeasQ/2)/ 128;
                qCoffDenom = powerMeasQ / 64;
                /* Protect against divide-by-0 */
                if (powerMeasQ != 0) {
                        /* IQ corr_meas is already negated if iqcorr_neg == 1 */
                        int32_t iCoff = iqCorrMeas/iCoffDenom;
                        int32_t qCoff = powerMeasI/qCoffDenom - 64;
 
                        HALDEBUG(ah, HAL_DEBUG_PERCAL, " iCoff = 0x%08x\n",
                            iCoff);
                        HALDEBUG(ah, HAL_DEBUG_PERCAL, " qCoff = 0x%08x\n",
                            qCoff);
         
                        /* Negate iCoff if iqCorrNeg == 0 */
                        iCoff = iCoff & 0x3f;
                        HALDEBUG(ah, HAL_DEBUG_PERCAL,
                            "New:  iCoff = 0x%08x\n", iCoff);
 
                        if (iqCorrNeg == 0x0)
                                iCoff = 0x40 - iCoff;
                        if (qCoff > 15)
                                qCoff = 15;
                        else if (qCoff <= -16)
                                qCoff = -16;
                        HALDEBUG(ah, HAL_DEBUG_PERCAL,
                            " : iCoff = 0x%x  qCoff = 0x%x\n", iCoff, qCoff);
 
                        OS_REG_RMW_FIELD(ah, AR_PHY_TIMING_CTRL4_CHAIN(i),
                            AR_PHY_TIMING_CTRL4_IQCORR_Q_I_COFF, iCoff);
                        OS_REG_RMW_FIELD(ah, AR_PHY_TIMING_CTRL4_CHAIN(i),
                            AR_PHY_TIMING_CTRL4_IQCORR_Q_Q_COFF, qCoff);
                        HALDEBUG(ah, HAL_DEBUG_PERCAL,
                            "IQ Cal and Correction done for Chain %d\n", i);
                }
        }
        OS_REG_SET_BIT(ah, AR_PHY_TIMING_CTRL4,
            AR_PHY_TIMING_CTRL4_IQCORR_ENABLE);
}