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path: root/host/lib/usrp/dboard/db_rfx.cpp
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//
// Copyright 2010-2012 Ettus Research LLC
//
// SPDX-License-Identifier: GPL-3.0
//

// IO Pin functions
#define POWER_IO     (1 << 7)   // Low enables power supply
#define ANTSW_IO     (1 << 6)   // On TX DB, 0 = TX, 1 = RX, on RX DB 0 = main ant, 1 = RX2
#define MIXER_IO     (1 << 5)   // Enable appropriate mixer
#define LOCKDET_MASK (1 << 2)   // Input pin

// Mixer constants
#define MIXER_ENB    MIXER_IO
#define MIXER_DIS    0

// Antenna constants
#define ANT_TX       0          //the tx line is transmitting
#define ANT_RX       ANTSW_IO   //the tx line is receiving
#define ANT_TXRX     0          //the rx line is on txrx
#define ANT_RX2      ANTSW_IO   //the rx line in on rx2
#define ANT_XX       0          //dont care how the antenna is set

#include "adf4360_regs.hpp"
#include <uhd/types/dict.hpp>
#include <uhd/types/ranges.hpp>
#include <uhd/types/sensors.hpp>
#include <uhd/utils/assert_has.hpp>
#include <uhd/utils/log.hpp>
#include <uhd/utils/static.hpp>
#include <uhd/utils/algorithm.hpp>

#include <uhd/usrp/dboard_id.hpp>
#include <uhd/usrp/dboard_base.hpp>
#include <uhd/usrp/dboard_manager.hpp>
#include <boost/assign/list_of.hpp>
#include <boost/bind.hpp>
#include <boost/format.hpp>
#include <boost/math/special_functions/round.hpp>

using namespace uhd;
using namespace uhd::usrp;
using namespace boost::assign;

/***********************************************************************
 * The RFX Series constants
 **********************************************************************/
static const std::vector<std::string> rfx_tx_antennas = list_of("TX/RX")("CAL");

static const std::vector<std::string> rfx_rx_antennas = list_of("TX/RX")("RX2")("CAL");

static const uhd::dict<std::string, gain_range_t> rfx_rx_gain_ranges = map_list_of
    ("PGA0", gain_range_t(0, 70, 0.022))
;

static const uhd::dict<std::string, gain_range_t> rfx400_rx_gain_ranges = map_list_of
    ("PGA0", gain_range_t(0, 45, 0.022))
;

/***********************************************************************
 * The RFX series of dboards
 **********************************************************************/
class rfx_xcvr : public xcvr_dboard_base{
public:
    rfx_xcvr(
        ctor_args_t args,
        const freq_range_t &freq_range,
        bool rx_div2, bool tx_div2
    );
    virtual ~rfx_xcvr(void);

private:
    const freq_range_t _freq_range;
    const uhd::dict<std::string, gain_range_t> _rx_gain_ranges;
    const uhd::dict<dboard_iface::unit_t, bool> _div2;
    std::string  _rx_ant;
    uhd::dict<std::string, double> _rx_gains;
    uint16_t _power_up;

    void set_rx_ant(const std::string &ant);
    void set_tx_ant(const std::string &ant);
    double set_rx_gain(double gain, const std::string &name);

    /*!
     * Set the LO frequency for the particular dboard unit.
     * \param unit which unit rx or tx
     * \param target_freq the desired frequency in Hz
     * \return the actual frequency in Hz
     */
    double set_lo_freq(dboard_iface::unit_t unit, double target_freq);

    /*!
     * Get the lock detect status of the LO.
     * \param unit which unit rx or tx
     * \return sensor for locked
     */
    sensor_value_t get_locked(dboard_iface::unit_t unit){
        const bool locked = (this->get_iface()->read_gpio(unit) & LOCKDET_MASK) != 0;
        return sensor_value_t("LO", locked, "locked", "unlocked");
    }

    /*!
     * Removed incorrect/confusing RSSI calculation
     * Limited dynamic range of sensor makes this less useful
     */
};

/***********************************************************************
 * Register the RFX dboards (min freq, max freq, rx div2, tx div2)
 **********************************************************************/
static dboard_base::sptr make_rfx_flex400(dboard_base::ctor_args_t args){
    return dboard_base::sptr(new rfx_xcvr(args, freq_range_t(400e6, 500e6), true, true));
}

static dboard_base::sptr make_rfx_flex900(dboard_base::ctor_args_t args){
    return dboard_base::sptr(new rfx_xcvr(args, freq_range_t(750e6, 1050e6), true, true));
}

static dboard_base::sptr make_rfx_flex1800(dboard_base::ctor_args_t args){
    return dboard_base::sptr(new rfx_xcvr(args, freq_range_t(1500e6, 2100e6), false, false));
}

static dboard_base::sptr make_rfx_flex1200(dboard_base::ctor_args_t args){
    return dboard_base::sptr(new rfx_xcvr(args, freq_range_t(1150e6, 1450e6), true, true));
}

static dboard_base::sptr make_rfx_flex2200(dboard_base::ctor_args_t args){
    return dboard_base::sptr(new rfx_xcvr(args, freq_range_t(2000e6, 2400e6), false, false));
}

static dboard_base::sptr make_rfx_flex2400(dboard_base::ctor_args_t args){
    return dboard_base::sptr(new rfx_xcvr(args, freq_range_t(2300e6, 2900e6), false, false));
}

UHD_STATIC_BLOCK(reg_rfx_dboards){
    dboard_manager::register_dboard(0x0024, 0x0028, &make_rfx_flex400,  "RFX400");
    dboard_manager::register_dboard(0x0025, 0x0029, &make_rfx_flex900,  "RFX900");
    dboard_manager::register_dboard(0x0034, 0x0035, &make_rfx_flex1800, "RFX1800");
    dboard_manager::register_dboard(0x0026, 0x002a, &make_rfx_flex1200, "RFX1200");
    dboard_manager::register_dboard(0x002c, 0x002d, &make_rfx_flex2200, "RFX2200");
    dboard_manager::register_dboard(0x0027, 0x002b, &make_rfx_flex2400, "RFX2400");
}

/***********************************************************************
 * Structors
 **********************************************************************/
rfx_xcvr::rfx_xcvr(
    ctor_args_t args,
    const freq_range_t &freq_range,
    bool rx_div2, bool tx_div2
):
    xcvr_dboard_base(args),
    _freq_range(freq_range),
    _rx_gain_ranges((get_rx_id() == 0x0024)?
        rfx400_rx_gain_ranges : rfx_rx_gain_ranges
    ),
    _div2(map_list_of
        (dboard_iface::UNIT_RX, rx_div2)
        (dboard_iface::UNIT_TX, tx_div2)
    ),
    _power_up((get_rx_id() == 0x0024 && get_tx_id() == 0x0028) ? POWER_IO : 0)
{
    ////////////////////////////////////////////////////////////////////
    // Register RX properties
    ////////////////////////////////////////////////////////////////////
    if(get_rx_id() == 0x0024) this->get_rx_subtree()->create<std::string>("name").set("RFX400 RX");
    else if(get_rx_id() == 0x0025) this->get_rx_subtree()->create<std::string>("name").set("RFX900 RX");
    else if(get_rx_id() == 0x0034) this->get_rx_subtree()->create<std::string>("name").set("RFX1800 RX");
    else if(get_rx_id() == 0x0026) this->get_rx_subtree()->create<std::string>("name").set("RFX1200 RX");
    else if(get_rx_id() == 0x002c) this->get_rx_subtree()->create<std::string>("name").set("RFX2200 RX");
    else if(get_rx_id() == 0x0027) this->get_rx_subtree()->create<std::string>("name").set("RFX2400 RX");
    else this->get_rx_subtree()->create<std::string>("name").set("RFX RX");

    this->get_rx_subtree()->create<sensor_value_t>("sensors/lo_locked")
        .set_publisher(boost::bind(&rfx_xcvr::get_locked, this, dboard_iface::UNIT_RX));
    for(const std::string &name:  _rx_gain_ranges.keys()){
        this->get_rx_subtree()->create<double>("gains/"+name+"/value")
            .set_coercer(boost::bind(&rfx_xcvr::set_rx_gain, this, _1, name))
            .set(_rx_gain_ranges[name].start());
        this->get_rx_subtree()->create<meta_range_t>("gains/"+name+"/range")
            .set(_rx_gain_ranges[name]);
    }
    this->get_rx_subtree()->create<double>("freq/value")
        .set_coercer(boost::bind(&rfx_xcvr::set_lo_freq, this, dboard_iface::UNIT_RX, _1))
        .set((_freq_range.start() + _freq_range.stop())/2.0);
    this->get_rx_subtree()->create<meta_range_t>("freq/range").set(_freq_range);
    this->get_rx_subtree()->create<std::string>("antenna/value")
        .add_coerced_subscriber(boost::bind(&rfx_xcvr::set_rx_ant, this, _1))
        .set("RX2");
    this->get_rx_subtree()->create<std::vector<std::string> >("antenna/options")
        .set(rfx_rx_antennas);
    this->get_rx_subtree()->create<std::string>("connection").set("QI");
    this->get_rx_subtree()->create<bool>("enabled").set(true); //always enabled
    this->get_rx_subtree()->create<bool>("use_lo_offset").set(false);
    this->get_rx_subtree()->create<double>("bandwidth/value").set(2*20.0e6); //20MHz low-pass, we want complex double-sided
    this->get_rx_subtree()->create<meta_range_t>("bandwidth/range")
        .set(freq_range_t(2*20.0e6, 2*20.0e6));

    ////////////////////////////////////////////////////////////////////
    // Register TX properties
    ////////////////////////////////////////////////////////////////////
    if(get_tx_id() == 0x0028) this->get_tx_subtree()->create<std::string>("name").set("RFX400 TX");
    else if(get_tx_id() == 0x0029) this->get_tx_subtree()->create<std::string>("name").set("RFX900 TX");
    else if(get_tx_id() == 0x0035) this->get_tx_subtree()->create<std::string>("name").set("RFX1800 TX");
    else if(get_tx_id() == 0x002a) this->get_tx_subtree()->create<std::string>("name").set("RFX1200 TX");
    else if(get_tx_id() == 0x002d) this->get_tx_subtree()->create<std::string>("name").set("RFX2200 TX");
    else if(get_tx_id() == 0x002b) this->get_tx_subtree()->create<std::string>("name").set("RFX2400 TX");
    else this->get_tx_subtree()->create<std::string>("name").set("RFX TX");

    this->get_tx_subtree()->create<sensor_value_t>("sensors/lo_locked")
        .set_publisher(boost::bind(&rfx_xcvr::get_locked, this, dboard_iface::UNIT_TX));
    this->get_tx_subtree()->create<int>("gains"); //phony property so this dir exists
    this->get_tx_subtree()->create<double>("freq/value")
        .set_coercer(boost::bind(&rfx_xcvr::set_lo_freq, this, dboard_iface::UNIT_TX, _1))
        .set((_freq_range.start() + _freq_range.stop())/2.0);
    this->get_tx_subtree()->create<meta_range_t>("freq/range").set(_freq_range);
    this->get_tx_subtree()->create<std::string>("antenna/value")
        .add_coerced_subscriber(boost::bind(&rfx_xcvr::set_tx_ant, this, _1)).set(rfx_tx_antennas.at(0));
    this->get_tx_subtree()->create<std::vector<std::string> >("antenna/options")
        .set(rfx_tx_antennas);
    this->get_tx_subtree()->create<std::string>("connection").set("IQ");
    this->get_tx_subtree()->create<bool>("enabled").set(true); //always enabled
    this->get_tx_subtree()->create<bool>("use_lo_offset").set(true);
    this->get_tx_subtree()->create<double>("bandwidth/value").set(2*20.0e6); //20MHz low-pass, we want complex double-sided
    this->get_tx_subtree()->create<meta_range_t>("bandwidth/range")
        .set(freq_range_t(2*20.0e6, 2*20.0e6));

    //enable the clocks that we need
    this->get_iface()->set_clock_enabled(dboard_iface::UNIT_TX, true);
    this->get_iface()->set_clock_enabled(dboard_iface::UNIT_RX, true);

    //set the gpio directions and atr controls (identically)
    uint16_t output_enables = POWER_IO | ANTSW_IO | MIXER_IO;
    this->get_iface()->set_pin_ctrl(dboard_iface::UNIT_TX, output_enables);
    this->get_iface()->set_pin_ctrl(dboard_iface::UNIT_RX, output_enables);
    this->get_iface()->set_gpio_ddr(dboard_iface::UNIT_TX, output_enables);
    this->get_iface()->set_gpio_ddr(dboard_iface::UNIT_RX, output_enables);

    //setup the tx atr (this does not change with antenna)
    this->get_iface()->set_atr_reg(dboard_iface::UNIT_TX, gpio_atr::ATR_REG_IDLE,        _power_up | ANT_XX | MIXER_DIS);
    this->get_iface()->set_atr_reg(dboard_iface::UNIT_TX, gpio_atr::ATR_REG_RX_ONLY,     _power_up | ANT_RX | MIXER_DIS);
    this->get_iface()->set_atr_reg(dboard_iface::UNIT_TX, gpio_atr::ATR_REG_TX_ONLY,     _power_up | ANT_TX | MIXER_ENB);
    this->get_iface()->set_atr_reg(dboard_iface::UNIT_TX, gpio_atr::ATR_REG_FULL_DUPLEX, _power_up | ANT_TX | MIXER_ENB);

    //setup the rx atr (this does not change with antenna)
    this->get_iface()->set_atr_reg(dboard_iface::UNIT_RX, gpio_atr::ATR_REG_IDLE,        _power_up | ANT_XX | MIXER_DIS);
    this->get_iface()->set_atr_reg(dboard_iface::UNIT_RX, gpio_atr::ATR_REG_TX_ONLY,     _power_up | ANT_XX | MIXER_DIS);
    this->get_iface()->set_atr_reg(dboard_iface::UNIT_RX, gpio_atr::ATR_REG_FULL_DUPLEX, _power_up | ANT_RX2| MIXER_ENB);
}

rfx_xcvr::~rfx_xcvr(void){
    /* NOP */
}

/***********************************************************************
 * Antenna Handling
 **********************************************************************/
void rfx_xcvr::set_rx_ant(const std::string &ant){
    //validate input
    assert_has(rfx_rx_antennas, ant, "rfx rx antenna name");

    //set the rx atr regs that change with antenna setting
    if (ant == "CAL") {
        this->get_iface()->set_atr_reg(dboard_iface::UNIT_RX, gpio_atr::ATR_REG_TX_ONLY,     _power_up | ANT_TXRX  | MIXER_ENB);
        this->get_iface()->set_atr_reg(dboard_iface::UNIT_RX, gpio_atr::ATR_REG_FULL_DUPLEX, _power_up | ANT_TXRX  | MIXER_ENB);
        this->get_iface()->set_atr_reg(dboard_iface::UNIT_RX, gpio_atr::ATR_REG_RX_ONLY,     _power_up | MIXER_ENB | ANT_TXRX );
    } 
    else {
        this->get_iface()->set_atr_reg(dboard_iface::UNIT_RX, gpio_atr::ATR_REG_TX_ONLY,     _power_up | ANT_XX | MIXER_DIS);
        this->get_iface()->set_atr_reg(dboard_iface::UNIT_RX, gpio_atr::ATR_REG_FULL_DUPLEX, _power_up | ANT_RX2| MIXER_ENB);
        this->get_iface()->set_atr_reg(dboard_iface::UNIT_RX, gpio_atr::ATR_REG_RX_ONLY,     _power_up | MIXER_ENB |
            ((ant == "TX/RX")? ANT_TXRX : ANT_RX2));
    }

    //shadow the setting
    _rx_ant = ant;
}

void rfx_xcvr::set_tx_ant(const std::string &ant){
    assert_has(rfx_tx_antennas, ant, "rfx tx antenna name");

    //set the tx atr regs that change with antenna setting
    if (ant == "CAL") {
        this->get_iface()->set_atr_reg(dboard_iface::UNIT_TX, gpio_atr::ATR_REG_TX_ONLY,     _power_up | ANT_RX | MIXER_ENB);
        this->get_iface()->set_atr_reg(dboard_iface::UNIT_TX, gpio_atr::ATR_REG_FULL_DUPLEX, _power_up | ANT_RX | MIXER_ENB);
    } 
    else {
        this->get_iface()->set_atr_reg(dboard_iface::UNIT_TX, gpio_atr::ATR_REG_TX_ONLY,     _power_up | ANT_TX | MIXER_ENB);
        this->get_iface()->set_atr_reg(dboard_iface::UNIT_TX, gpio_atr::ATR_REG_FULL_DUPLEX, _power_up | ANT_TX | MIXER_ENB);
    }
}

/***********************************************************************
 * Gain Handling
 **********************************************************************/
static double rx_pga0_gain_to_dac_volts(double &gain, double range){
    //voltage level constants (negative slope)
    static const double max_volts = .2, min_volts = 1.2;
    static const double slope = (max_volts-min_volts)/(range);

    //calculate the voltage for the aux dac
    double dac_volts = uhd::clip<double>(gain*slope + min_volts, max_volts, min_volts);

    //the actual gain setting
    gain = (dac_volts - min_volts)/slope;

    return dac_volts;
}

double rfx_xcvr::set_rx_gain(double gain, const std::string &name){
    assert_has(_rx_gain_ranges.keys(), name, "rfx rx gain name");
    if(name == "PGA0"){
        double dac_volts = rx_pga0_gain_to_dac_volts(gain, 
                              (_rx_gain_ranges["PGA0"].stop() - _rx_gain_ranges["PGA0"].start()));

        //write the new voltage to the aux dac
        this->get_iface()->write_aux_dac(dboard_iface::UNIT_RX, dboard_iface::AUX_DAC_A, dac_volts);

        return gain;
    }
    else UHD_THROW_INVALID_CODE_PATH();
}

/***********************************************************************
 * Tuning
 **********************************************************************/
double rfx_xcvr::set_lo_freq(
    dboard_iface::unit_t unit,
    double target_freq
){
    UHD_LOGGER_TRACE("RFX") << boost::format(
        "RFX tune: target frequency %f MHz"
    ) % (target_freq/1e6) ;

    //clip the input
    target_freq = _freq_range.clip(target_freq);
    if (_div2[unit]) target_freq *= 2;

    //rfx400 rx is a special case with div2 in mixer, so adf4360 must output fundamental
    bool is_rx_rfx400 = ((get_rx_id() == 0x0024) && unit != dboard_iface::UNIT_TX);

    //map prescalers to the register enums
    static const uhd::dict<int, adf4360_regs_t::prescaler_value_t> prescaler_to_enum = map_list_of
        (8,  adf4360_regs_t::PRESCALER_VALUE_8_9)
        (16, adf4360_regs_t::PRESCALER_VALUE_16_17)
        (32, adf4360_regs_t::PRESCALER_VALUE_32_33)
    ;

    //map band select clock dividers to enums
    static const uhd::dict<int, adf4360_regs_t::band_select_clock_div_t> bandsel_to_enum = map_list_of
        (1, adf4360_regs_t::BAND_SELECT_CLOCK_DIV_1)
        (2, adf4360_regs_t::BAND_SELECT_CLOCK_DIV_2)
        (4, adf4360_regs_t::BAND_SELECT_CLOCK_DIV_4)
        (8, adf4360_regs_t::BAND_SELECT_CLOCK_DIV_8)
    ;

    double actual_freq=0, ref_freq = this->get_iface()->get_clock_rate(unit);
    int R=0, BS=0, P=0, B=0, A=0;

    /*
     * The goal here to to loop though possible R dividers,
     * band select clock dividers, and prescaler values.
     * Calculate the A and B counters for each set of values.
     * The loop exits when it meets all of the constraints.
     * The resulting loop values are loaded into the registers.
     *
     * fvco = [P*B + A] * fref/R
     * fvco*R/fref = P*B + A = N
     */
    for(R = 2; R <= 32; R+=2){
        for(auto BS:  bandsel_to_enum.keys()){
            if (ref_freq/R/BS > 1e6) continue; //constraint on band select clock
            for(auto P:  prescaler_to_enum.keys()){
                //calculate B and A from N
                double N = target_freq*R/ref_freq;
                B = int(std::floor(N/P));
                A = boost::math::iround(N - P*B);
                if (B < A or B > 8191 or B < 3 or A > 31) continue; //constraints on A, B
                //calculate the actual frequency
                actual_freq = double(P*B + A)*ref_freq/R;
                if (actual_freq/P > 300e6) continue; //constraint on prescaler output
                //constraints met: exit loop
                goto done_loop;
            }
        }
    } done_loop:

    UHD_LOGGER_TRACE("RFX") << boost::format(
        "RFX tune: R=%d, BS=%d, P=%d, B=%d, A=%d, DIV2=%d"
    ) % R % BS % P % B % A % int(_div2[unit] && (!is_rx_rfx400)) ;

    //load the register values
    adf4360_regs_t regs;
    regs.core_power_level        = adf4360_regs_t::CORE_POWER_LEVEL_10MA;
    regs.counter_operation       = adf4360_regs_t::COUNTER_OPERATION_NORMAL;
    regs.muxout_control          = adf4360_regs_t::MUXOUT_CONTROL_DLD;
    regs.phase_detector_polarity = adf4360_regs_t::PHASE_DETECTOR_POLARITY_POS;
    regs.charge_pump_output      = adf4360_regs_t::CHARGE_PUMP_OUTPUT_NORMAL;
    regs.cp_gain_0               = adf4360_regs_t::CP_GAIN_0_SET1;
    regs.mute_till_ld            = adf4360_regs_t::MUTE_TILL_LD_ENB;
    regs.output_power_level      = adf4360_regs_t::OUTPUT_POWER_LEVEL_3_5MA;
    regs.current_setting1        = adf4360_regs_t::CURRENT_SETTING1_0_31MA;
    regs.current_setting2        = adf4360_regs_t::CURRENT_SETTING2_0_31MA;
    regs.power_down              = adf4360_regs_t::POWER_DOWN_NORMAL_OP;
    regs.prescaler_value         = prescaler_to_enum[P];
    regs.a_counter               = A;
    regs.b_counter               = B;
    regs.cp_gain_1               = adf4360_regs_t::CP_GAIN_1_SET1;
    regs.divide_by_2_output      = (_div2[unit] && (!is_rx_rfx400)) ?  // Special case RFX400 RX Mixer divides by two
                                    adf4360_regs_t::DIVIDE_BY_2_OUTPUT_DIV2 :
                                    adf4360_regs_t::DIVIDE_BY_2_OUTPUT_FUND ;
    regs.divide_by_2_prescaler   = adf4360_regs_t::DIVIDE_BY_2_PRESCALER_FUND;
    regs.r_counter               = R;
    regs.ablpw                   = adf4360_regs_t::ABLPW_3_0NS;
    regs.lock_detect_precision   = adf4360_regs_t::LOCK_DETECT_PRECISION_5CYCLES;
    regs.test_mode_bit           = 0;
    regs.band_select_clock_div   = bandsel_to_enum[BS];

    //write the registers
    std::vector<adf4360_regs_t::addr_t> addrs = list_of //correct power-up sequence to write registers (R, C, N)
        (adf4360_regs_t::ADDR_RCOUNTER)
        (adf4360_regs_t::ADDR_CONTROL)
        (adf4360_regs_t::ADDR_NCOUNTER)
    ;
    for(adf4360_regs_t::addr_t addr:  addrs){
        this->get_iface()->write_spi(
            unit, spi_config_t::EDGE_RISE,
            regs.get_reg(addr), 24
        );
    }

    //return the actual frequency
    if (_div2[unit]) actual_freq /= 2;
    UHD_LOGGER_TRACE("RFX") << boost::format(
        "RFX tune: actual frequency %f MHz"
    ) % (actual_freq/1e6) ;
    return actual_freq;
}