//
// Copyright 2013-2014 Ettus Research LLC
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with this program. If not, see .
//
#include "lmk04816_regs.hpp"
#include "x300_clock_ctrl.hpp"
#include
#include
#include
#include
#include
#include
static const double X300_REF_CLK_OUT_RATE = 10e6;
static const boost::uint16_t X300_MAX_CLKOUT_DIV = 1045;
static const double X300_DEFAULT_DBOARD_CLK_RATE = 50e6;
using namespace uhd;
x300_clock_ctrl::~x300_clock_ctrl(void){
/* NOP */
}
class x300_clock_ctrl_impl : public x300_clock_ctrl {
public:
~x300_clock_ctrl_impl(void) {}
x300_clock_ctrl_impl(uhd::spi_iface::sptr spiface,
const size_t slaveno,
const size_t hw_rev,
const double master_clock_rate,
const double system_ref_rate):
_spiface(spiface),
_slaveno(slaveno),
_hw_rev(hw_rev),
_master_clock_rate(master_clock_rate),
_system_ref_rate(system_ref_rate)
{
init();
}
void reset_clocks() {
_lmk04816_regs.RESET = lmk04816_regs_t::RESET_RESET;
this->write_regs(0);
_lmk04816_regs.RESET = lmk04816_regs_t::RESET_NO_RESET;
for (size_t i = 0; i <= 16; ++i) {
this->write_regs(i);
}
for (size_t i = 24; i <= 31; ++i) {
this->write_regs(i);
}
sync_clocks();
}
void sync_clocks(void) {
//soft sync:
//put the sync IO into output mode - FPGA must be input
//write low, then write high - this triggers a soft sync
_lmk04816_regs.SYNC_POL_INV = lmk04816_regs_t::SYNC_POL_INV_SYNC_LOW;
this->write_regs(11);
_lmk04816_regs.SYNC_POL_INV = lmk04816_regs_t::SYNC_POL_INV_SYNC_HIGH;
this->write_regs(11);
}
double get_master_clock_rate(void) {
return _master_clock_rate;
}
double get_sysref_clock_rate(void) {
return _system_ref_rate;
}
double get_refout_clock_rate(void) {
//We support only one reference output rate
return X300_REF_CLK_OUT_RATE;
}
void set_dboard_rate(const x300_clock_which_t which, double rate) {
boost::uint16_t div = boost::uint16_t(_vco_freq / rate);
boost::uint16_t *reg = NULL;
boost::uint8_t addr = 0xFF;
// Make sure requested rate is an even divisor of the VCO frequency
if (not doubles_are_equal(_vco_freq / div, rate))
throw uhd::value_error("invalid dboard rate requested");
switch (which)
{
case X300_CLOCK_WHICH_DB0_RX:
case X300_CLOCK_WHICH_DB1_RX:
reg = &_lmk04816_regs.CLKout2_3_DIV;
addr = 1;
break;
case X300_CLOCK_WHICH_DB0_TX:
case X300_CLOCK_WHICH_DB1_TX:
reg = &_lmk04816_regs.CLKout4_5_DIV;
addr = 2;
break;
default:
UHD_THROW_INVALID_CODE_PATH();
}
if (*reg == div)
return;
// Since the clock rate on one daughter board cannot be changed without
// affecting the other daughter board, don't allow it.
throw uhd::not_implemented_error("x3xx set dboard clock rate does not support changing the clock rate");
// This is open source code and users may need to enable this function
// to support other daughterboards. If so, comment out the line above
// that throws the error and allow the program to reach the code below.
// The LMK04816 datasheet says the register must be written twice if SYNC is enabled
*reg = div;
write_regs(addr);
write_regs(addr);
sync_clocks();
}
double get_dboard_rate(const x300_clock_which_t which)
{
double rate = 0.0;
switch (which)
{
case X300_CLOCK_WHICH_DB0_RX:
case X300_CLOCK_WHICH_DB1_RX:
rate = _vco_freq / _lmk04816_regs.CLKout2_3_DIV;
break;
case X300_CLOCK_WHICH_DB0_TX:
case X300_CLOCK_WHICH_DB1_TX:
rate = _vco_freq / _lmk04816_regs.CLKout4_5_DIV;
break;
default:
UHD_THROW_INVALID_CODE_PATH();
}
return rate;
}
std::vector get_dboard_rates(const x300_clock_which_t)
{
std::vector rates;
for (size_t div = size_t(_vco_freq / _master_clock_rate); div <= X300_MAX_CLKOUT_DIV; div++)
rates.push_back(_vco_freq / div);
return rates;
}
void enable_dboard_clock(const x300_clock_which_t which, const bool enable)
{
switch (which)
{
case X300_CLOCK_WHICH_DB0_RX:
if (enable != (_lmk04816_regs.CLKout2_TYPE == lmk04816_regs_t::CLKOUT2_TYPE_LVPECL_700MVPP))
{
_lmk04816_regs.CLKout2_TYPE = enable ? lmk04816_regs_t::CLKOUT2_TYPE_LVPECL_700MVPP : lmk04816_regs_t::CLKOUT2_TYPE_P_DOWN;
write_regs(6);
}
break;
case X300_CLOCK_WHICH_DB1_RX:
if (enable != (_lmk04816_regs.CLKout3_TYPE == lmk04816_regs_t::CLKOUT3_TYPE_LVPECL_700MVPP))
{
_lmk04816_regs.CLKout3_TYPE = enable ? lmk04816_regs_t::CLKOUT3_TYPE_LVPECL_700MVPP : lmk04816_regs_t::CLKOUT3_TYPE_P_DOWN;
write_regs(6);
}
break;
case X300_CLOCK_WHICH_DB0_TX:
if (enable != (_lmk04816_regs.CLKout5_TYPE == lmk04816_regs_t::CLKOUT5_TYPE_LVPECL_700MVPP))
{
_lmk04816_regs.CLKout5_TYPE = enable ? lmk04816_regs_t::CLKOUT5_TYPE_LVPECL_700MVPP : lmk04816_regs_t::CLKOUT5_TYPE_P_DOWN;
write_regs(7);
}
break;
case X300_CLOCK_WHICH_DB1_TX:
if (enable != (_lmk04816_regs.CLKout4_TYPE == lmk04816_regs_t::CLKOUT4_TYPE_LVPECL_700MVPP))
{
_lmk04816_regs.CLKout4_TYPE = enable ? lmk04816_regs_t::CLKOUT4_TYPE_LVPECL_700MVPP : lmk04816_regs_t::CLKOUT4_TYPE_P_DOWN;
write_regs(7);
}
break;
default:
UHD_THROW_INVALID_CODE_PATH();
}
}
void set_ref_out(const bool enable) {
// TODO Implement divider configuration to allow for configurable output
// rates
if (enable)
_lmk04816_regs.CLKout10_TYPE = lmk04816_regs_t::CLKOUT10_TYPE_LVDS;
else
_lmk04816_regs.CLKout10_TYPE = lmk04816_regs_t::CLKOUT10_TYPE_P_DOWN;
this->write_regs(8);
}
void write_regs(boost::uint8_t addr) {
boost::uint32_t data = _lmk04816_regs.get_reg(addr);
_spiface->write_spi(_slaveno, spi_config_t::EDGE_RISE, data,32);
}
private:
void init() {
/* The X3xx has two primary rates. The first is the
* _system_ref_rate, which is sourced from the "clock_source"/"value" field
* of the property tree, and whose value can be 10e6, 30.72e6, or 200e6.
* The _system_ref_rate is the input to the clocking system, and
* what comes out is a disciplined master clock running at the
* _master_clock_rate. As such, only certain combinations of
* system reference rates and master clock rates are supported.
* Additionally, a subset of these will operate in "zero delay" mode. */
enum opmode_t { INVALID,
m10M_200M_NOZDEL, // used for debug purposes only
m10M_200M_ZDEL, // Normal mode
m30_72M_184_32M_ZDEL, // LTE with external ref, aka CPRI Mode
m10M_184_32M_NOZDEL, // LTE with 10 MHz ref
m10M_120M_ZDEL }; // NI USRP 120 MHz Clocking
/* The default clocking mode is 10MHz reference generating a 200 MHz master
* clock, in zero-delay mode. */
opmode_t clocking_mode = INVALID;
if(doubles_are_equal(_system_ref_rate, 10e6)) {
if(doubles_are_equal(_master_clock_rate, 184.32e6)) {
/* 10MHz reference, 184.32 MHz master clock out, NOT Zero Delay. */
clocking_mode = m10M_184_32M_NOZDEL;
} else if(doubles_are_equal(_master_clock_rate, 200e6)) {
/* 10MHz reference, 200 MHz master clock out, Zero Delay */
clocking_mode = m10M_200M_ZDEL;
} else if(doubles_are_equal(_master_clock_rate, 120e6)) {
/* 10MHz reference, 120 MHz master clock rate, Zero Delay */
clocking_mode = m10M_120M_ZDEL;
}
} else if(doubles_are_equal(_system_ref_rate, 30.72e6)) {
if(doubles_are_equal(_master_clock_rate, 184.32e6)) {
/* 30.72MHz reference, 184.32 MHz master clock out, Zero Delay */
clocking_mode = m30_72M_184_32M_ZDEL;
}
}
if(clocking_mode == INVALID) {
throw uhd::runtime_error(str(boost::format("A master clock rate of %f cannot be derived from a system reference rate of %f") % _master_clock_rate % _system_ref_rate));
}
// For 200 MHz output, the VCO is run at 2400 MHz
// For the LTE/CPRI rate of 184.32 MHz, the VCO runs at 2580.48 MHz
// Note: PLL2 N2 prescaler is enabled for all cases
// PLL2 reference doubler is enabled for all cases
/* All LMK04816 settings are from the LMK datasheet for our clocking
* architecture. Please refer to the datasheet for more information. */
switch (clocking_mode) {
case m10M_200M_NOZDEL:
_vco_freq = 2400e6;
_lmk04816_regs.MODE = lmk04816_regs_t::MODE_DUAL_INT;
// PLL1 - 2 MHz compare frequency
_lmk04816_regs.PLL1_N_28 = 48;
_lmk04816_regs.PLL1_R_27 = 5;
_lmk04816_regs.PLL1_CP_GAIN_27 = lmk04816_regs_t::PLL1_CP_GAIN_27_100UA;
// PLL2 - 48 MHz compare frequency
_lmk04816_regs.PLL2_N_30 = 25;
_lmk04816_regs.PLL2_P_30 = lmk04816_regs_t::PLL2_P_30_DIV_2A;
_lmk04816_regs.PLL2_R_28 = 4;
_lmk04816_regs.PLL2_CP_GAIN_26 = lmk04816_regs_t::PLL2_CP_GAIN_26_3200UA;
break;
case m10M_200M_ZDEL:
_vco_freq = 2400e6;
_lmk04816_regs.MODE = lmk04816_regs_t::MODE_DUAL_INT_ZER_DELAY;
// PLL1 - 2 MHz compare frequency
_lmk04816_regs.PLL1_N_28 = 5;
_lmk04816_regs.PLL1_R_27 = 5;
_lmk04816_regs.PLL1_CP_GAIN_27 = lmk04816_regs_t::PLL1_CP_GAIN_27_1600UA;
// PLL2 - 96 MHz compare frequency
_lmk04816_regs.PLL2_N_30 = 5;
_lmk04816_regs.PLL2_P_30 = lmk04816_regs_t::PLL2_P_30_DIV_5;
_lmk04816_regs.PLL2_R_28 = 2;
if(_hw_rev <= 4)
_lmk04816_regs.PLL2_CP_GAIN_26 = lmk04816_regs_t::PLL2_CP_GAIN_26_1600UA;
else
_lmk04816_regs.PLL2_CP_GAIN_26 = lmk04816_regs_t::PLL2_CP_GAIN_26_400UA;
break;
case m30_72M_184_32M_ZDEL:
_vco_freq = 2580.48e6;
_lmk04816_regs.MODE = lmk04816_regs_t::MODE_DUAL_INT_ZER_DELAY;
// PLL1 - 2.048 MHz compare frequency
_lmk04816_regs.PLL1_N_28 = 15;
_lmk04816_regs.PLL1_R_27 = 15;
_lmk04816_regs.PLL1_CP_GAIN_27 = lmk04816_regs_t::PLL1_CP_GAIN_27_100UA;
// PLL2 - 7.68 MHz compare frequency
_lmk04816_regs.PLL2_N_30 = 168;
_lmk04816_regs.PLL2_P_30 = lmk04816_regs_t::PLL2_P_30_DIV_2A;
_lmk04816_regs.PLL2_R_28 = 25;
_lmk04816_regs.PLL2_CP_GAIN_26 = lmk04816_regs_t::PLL2_CP_GAIN_26_3200UA;
_lmk04816_regs.PLL2_R3_LF = lmk04816_regs_t::PLL2_R3_LF_1KILO_OHM;
_lmk04816_regs.PLL2_C3_LF = lmk04816_regs_t::PLL2_C3_LF_39PF;
_lmk04816_regs.PLL2_R4_LF = lmk04816_regs_t::PLL2_R4_LF_1KILO_OHM;
_lmk04816_regs.PLL2_C4_LF = lmk04816_regs_t::PLL2_C4_LF_34PF;
break;
case m10M_184_32M_NOZDEL:
_vco_freq = 2580.48e6;
_lmk04816_regs.MODE = lmk04816_regs_t::MODE_DUAL_INT;
// PLL1 - 2 MHz compare frequency
_lmk04816_regs.PLL1_N_28 = 48;
_lmk04816_regs.PLL1_R_27 = 5;
_lmk04816_regs.PLL1_CP_GAIN_27 = lmk04816_regs_t::PLL1_CP_GAIN_27_100UA;
// PLL2 - 7.68 MHz compare frequency
_lmk04816_regs.PLL2_N_30 = 168;
_lmk04816_regs.PLL2_P_30 = lmk04816_regs_t::PLL2_P_30_DIV_2A;
_lmk04816_regs.PLL2_R_28 = 25;
_lmk04816_regs.PLL2_CP_GAIN_26 = lmk04816_regs_t::PLL2_CP_GAIN_26_3200UA;
_lmk04816_regs.PLL2_R3_LF = lmk04816_regs_t::PLL2_R3_LF_4KILO_OHM;
_lmk04816_regs.PLL2_C3_LF = lmk04816_regs_t::PLL2_C3_LF_39PF;
_lmk04816_regs.PLL2_R4_LF = lmk04816_regs_t::PLL2_R4_LF_1KILO_OHM;
_lmk04816_regs.PLL2_C4_LF = lmk04816_regs_t::PLL2_C4_LF_71PF;
break;
case m10M_120M_ZDEL:
_vco_freq = 2400e6;
_lmk04816_regs.MODE = lmk04816_regs_t::MODE_DUAL_INT_ZER_DELAY;
// PLL1 - 2 MHz compare frequency
_lmk04816_regs.PLL1_N_28 = 5;
_lmk04816_regs.PLL1_R_27 = 5;
_lmk04816_regs.PLL1_CP_GAIN_27 = lmk04816_regs_t::PLL1_CP_GAIN_27_100UA;
// PLL2 - 96 MHz compare frequency
_lmk04816_regs.PLL2_N_30 = 5;
_lmk04816_regs.PLL2_P_30 = lmk04816_regs_t::PLL2_P_30_DIV_5;
_lmk04816_regs.PLL2_R_28 = 2;
if(_hw_rev <= 4)
_lmk04816_regs.PLL2_CP_GAIN_26 = lmk04816_regs_t::PLL2_CP_GAIN_26_1600UA;
else
_lmk04816_regs.PLL2_CP_GAIN_26 = lmk04816_regs_t::PLL2_CP_GAIN_26_400UA;
break;
default:
UHD_THROW_INVALID_CODE_PATH();
break;
};
boost::uint16_t master_clock_div = static_cast(
std::ceil(_vco_freq / _master_clock_rate));
boost::uint16_t dboard_div = static_cast(
std::ceil(_vco_freq / X300_DEFAULT_DBOARD_CLK_RATE));
/* Reset the LMK clock controller. */
_lmk04816_regs.RESET = lmk04816_regs_t::RESET_RESET;
this->write_regs(0);
_lmk04816_regs.RESET = lmk04816_regs_t::RESET_NO_RESET;
this->write_regs(0);
/* Initial power-up */
_lmk04816_regs.CLKout0_1_PD = lmk04816_regs_t::CLKOUT0_1_PD_POWER_UP;
this->write_regs(0);
_lmk04816_regs.CLKout0_1_DIV = master_clock_div;
_lmk04816_regs.CLKout0_ADLY_SEL = lmk04816_regs_t::CLKOUT0_ADLY_SEL_D_EV_X;
this->write_regs(0);
// Register 1
_lmk04816_regs.CLKout2_3_PD = lmk04816_regs_t::CLKOUT2_3_PD_POWER_UP;
_lmk04816_regs.CLKout2_3_DIV = dboard_div;
// Register 2
_lmk04816_regs.CLKout4_5_PD = lmk04816_regs_t::CLKOUT4_5_PD_POWER_UP;
_lmk04816_regs.CLKout4_5_DIV = dboard_div;
// Register 3
_lmk04816_regs.CLKout6_7_DIV = master_clock_div;
_lmk04816_regs.CLKout6_7_OSCin_Sel = lmk04816_regs_t::CLKOUT6_7_OSCIN_SEL_VCO;
// Register 4
_lmk04816_regs.CLKout8_9_DIV = master_clock_div;
// Register 5
_lmk04816_regs.CLKout10_11_PD = lmk04816_regs_t::CLKOUT10_11_PD_NORMAL;
_lmk04816_regs.CLKout10_11_DIV =
static_cast(std::ceil(_vco_freq / _system_ref_rate));
// Register 6
_lmk04816_regs.CLKout0_TYPE = lmk04816_regs_t::CLKOUT0_TYPE_LVDS; //FPGA
_lmk04816_regs.CLKout1_TYPE = lmk04816_regs_t::CLKOUT1_TYPE_P_DOWN; //CPRI feedback clock, use LVDS
_lmk04816_regs.CLKout2_TYPE = lmk04816_regs_t::CLKOUT2_TYPE_LVPECL_700MVPP; //DB_0_RX
_lmk04816_regs.CLKout3_TYPE = lmk04816_regs_t::CLKOUT3_TYPE_LVPECL_700MVPP; //DB_1_RX
// Analog delay of 900ps to synchronize the radio clock with the source synchronous ADC clocks.
// This delay may need to vary due to temperature. Tested and verified at room temperature only.
_lmk04816_regs.CLKout0_1_ADLY = 0x10;
// Register 7
_lmk04816_regs.CLKout4_TYPE = lmk04816_regs_t::CLKOUT4_TYPE_LVPECL_700MVPP; //DB_1_TX
_lmk04816_regs.CLKout5_TYPE = lmk04816_regs_t::CLKOUT5_TYPE_LVPECL_700MVPP; //DB_0_TX
_lmk04816_regs.CLKout6_TYPE = lmk04816_regs_t::CLKOUT6_TYPE_LVPECL_700MVPP; //DB0_DAC
_lmk04816_regs.CLKout7_TYPE = lmk04816_regs_t::CLKOUT7_TYPE_LVPECL_700MVPP; //DB1_DAC
_lmk04816_regs.CLKout8_TYPE = lmk04816_regs_t::CLKOUT8_TYPE_LVPECL_700MVPP; //DB0_ADC
// Register 8
_lmk04816_regs.CLKout9_TYPE = lmk04816_regs_t::CLKOUT9_TYPE_LVPECL_700MVPP; //DB1_ADC
_lmk04816_regs.CLKout10_TYPE = lmk04816_regs_t::CLKOUT10_TYPE_LVDS; //REF_CLKOUT
_lmk04816_regs.CLKout11_TYPE = lmk04816_regs_t::CLKOUT11_TYPE_P_DOWN; //Debug header, use LVPECL
// Register 10
_lmk04816_regs.EN_OSCout0 = lmk04816_regs_t::EN_OSCOUT0_DISABLED; //Debug header
_lmk04816_regs.FEEDBACK_MUX = 5; //use output 10 (REF OUT) for feedback
_lmk04816_regs.EN_FEEDBACK_MUX = lmk04816_regs_t::EN_FEEDBACK_MUX_ENABLED;
// Register 11
// MODE set in individual cases above
_lmk04816_regs.SYNC_QUAL = lmk04816_regs_t::SYNC_QUAL_FB_MUX;
_lmk04816_regs.EN_SYNC = lmk04816_regs_t::EN_SYNC_ENABLE;
_lmk04816_regs.NO_SYNC_CLKout0_1 = lmk04816_regs_t::NO_SYNC_CLKOUT0_1_CLOCK_XY_SYNC;
_lmk04816_regs.NO_SYNC_CLKout2_3 = lmk04816_regs_t::NO_SYNC_CLKOUT2_3_CLOCK_XY_SYNC;
_lmk04816_regs.NO_SYNC_CLKout4_5 = lmk04816_regs_t::NO_SYNC_CLKOUT4_5_CLOCK_XY_SYNC;
_lmk04816_regs.NO_SYNC_CLKout6_7 = lmk04816_regs_t::NO_SYNC_CLKOUT6_7_CLOCK_XY_SYNC;
_lmk04816_regs.NO_SYNC_CLKout8_9 = lmk04816_regs_t::NO_SYNC_CLKOUT8_9_CLOCK_XY_SYNC;
_lmk04816_regs.NO_SYNC_CLKout10_11 = lmk04816_regs_t::NO_SYNC_CLKOUT10_11_CLOCK_XY_SYNC;
_lmk04816_regs.SYNC_TYPE = lmk04816_regs_t::SYNC_TYPE_INPUT;
// Register 12
_lmk04816_regs.LD_MUX = lmk04816_regs_t::LD_MUX_BOTH;
/* Input Clock Configurations */
// Register 13
_lmk04816_regs.EN_CLKin0 = lmk04816_regs_t::EN_CLKIN0_NO_VALID_USE; // This is not connected
_lmk04816_regs.EN_CLKin2 = lmk04816_regs_t::EN_CLKIN2_NO_VALID_USE; // Used only for CPRI
_lmk04816_regs.Status_CLKin1_MUX = lmk04816_regs_t::STATUS_CLKIN1_MUX_UWIRE_RB;
_lmk04816_regs.CLKin_Select_MODE = lmk04816_regs_t::CLKIN_SELECT_MODE_CLKIN1_MAN;
_lmk04816_regs.HOLDOVER_MUX = lmk04816_regs_t::HOLDOVER_MUX_PLL1_R;
// Register 14
_lmk04816_regs.Status_CLKin1_TYPE = lmk04816_regs_t::STATUS_CLKIN1_TYPE_OUT_PUSH_PULL;
_lmk04816_regs.Status_CLKin0_TYPE = lmk04816_regs_t::STATUS_CLKIN0_TYPE_OUT_PUSH_PULL;
// Register 26
// PLL2_CP_GAIN_26 set above in individual cases
_lmk04816_regs.PLL2_CP_POL_26 = lmk04816_regs_t::PLL2_CP_POL_26_NEG_SLOPE;
_lmk04816_regs.EN_PLL2_REF_2X = lmk04816_regs_t::EN_PLL2_REF_2X_DOUBLED_FREQ_REF;
// Register 27
// PLL1_CP_GAIN_27 set in individual cases above
// PLL1_R_27 set in the individual cases above
// Register 28
// PLL1_N_28 and PLL2_R_28 are set in the individual cases above
// Register 29
_lmk04816_regs.PLL2_N_CAL_29 = _lmk04816_regs.PLL2_N_30; // N_CAL should always match N
_lmk04816_regs.OSCin_FREQ_29 = lmk04816_regs_t::OSCIN_FREQ_29_63_TO_127MHZ;
// Register 30
// PLL2_P_30 set in individual cases above
// PLL2_N_30 set in individual cases above
/* Write the configuration values into the LMK */
for (size_t i = 1; i <= 16; ++i) {
this->write_regs(i);
}
for (size_t i = 24; i <= 31; ++i) {
this->write_regs(i);
}
this->sync_clocks();
}
UHD_INLINE bool doubles_are_equal(double a, double b) {
return (std::fabs(a - b) < std::numeric_limits::epsilon());
}
const spi_iface::sptr _spiface;
const size_t _slaveno;
const size_t _hw_rev;
const double _master_clock_rate;
const double _system_ref_rate;
lmk04816_regs_t _lmk04816_regs;
double _vco_freq;
};
x300_clock_ctrl::sptr x300_clock_ctrl::make(uhd::spi_iface::sptr spiface,
const size_t slaveno,
const size_t hw_rev,
const double master_clock_rate,
const double system_ref_rate) {
return sptr(new x300_clock_ctrl_impl(spiface, slaveno, hw_rev,
master_clock_rate, system_ref_rate));
}