diff options
Diffstat (limited to 'host/lib/usrp/usrp_e100/clock_ctrl.cpp')
| -rw-r--r-- | host/lib/usrp/usrp_e100/clock_ctrl.cpp | 326 |
1 files changed, 264 insertions, 62 deletions
diff --git a/host/lib/usrp/usrp_e100/clock_ctrl.cpp b/host/lib/usrp/usrp_e100/clock_ctrl.cpp index 1fb1a7125..e29fe18ce 100644 --- a/host/lib/usrp/usrp_e100/clock_ctrl.cpp +++ b/host/lib/usrp/usrp_e100/clock_ctrl.cpp @@ -1,5 +1,5 @@ // -// Copyright 2010 Ettus Research LLC +// Copyright 2010-2011 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 @@ -22,11 +22,26 @@ #include "usrp_e100_regs.hpp" //spi slave constants #include <boost/assign/list_of.hpp> #include <boost/foreach.hpp> +#include <boost/format.hpp> +#include <boost/thread/thread.hpp> +#include <boost/math/common_factor_rt.hpp> //gcd +#include <algorithm> #include <utility> #include <iostream> using namespace uhd; +/*********************************************************************** + * Constants + **********************************************************************/ +static const bool CLOCK_SETTINGS_DEBUG = false; +static const bool ENABLE_THE_TEST_OUT = true; +static const double REFERENCE_INPUT_RATE = 10e6; +static const double DEFAULT_OUTPUT_RATE = 64e6; + +/*********************************************************************** + * Helpers + **********************************************************************/ template <typename div_type, typename bypass_type> static void set_clock_divider( size_t divider, div_type &low, div_type &high, bypass_type &bypass ){ @@ -36,24 +51,117 @@ template <typename div_type, typename bypass_type> static void set_clock_divider } /*********************************************************************** - * Constants + * Clock rate calculation stuff: + * Using the internal VCO between 1400 and 1800 MHz **********************************************************************/ -static const bool enable_test_clock = false; -static const size_t ref_clock_doubler = 2; //enabled below -static const double ref_clock_rate = 10e6 * ref_clock_doubler; +struct clock_settings_type{ + size_t ref_clock_doubler, r_counter, a_counter, b_counter, prescaler, vco_divider, chan_divider; + size_t get_n_counter(void) const{return prescaler * b_counter + a_counter;} + double get_ref_rate(void) const{return REFERENCE_INPUT_RATE * ref_clock_doubler;} + double get_vco_rate(void) const{return get_ref_rate()/r_counter * get_n_counter();} + double get_chan_rate(void) const{return get_vco_rate()/vco_divider;} + double get_out_rate(void) const{return get_chan_rate()/chan_divider;} + std::string to_pp_string(void) const{ + return str(boost::format( + " r_counter: %d\n" + " a_counter: %d\n" + " b_counter: %d\n" + " prescaler: %d\n" + " vco_divider: %d\n" + " chan_divider: %d\n" + " vco_rate: %fMHz\n" + " chan_rate: %fMHz\n" + " out_rate: %fMHz\n" + ) + % r_counter + % a_counter + % b_counter + % prescaler + % vco_divider + % chan_divider + % (get_vco_rate()/1e6) + % (get_chan_rate()/1e6) + % (get_out_rate()/1e6) + ); + } +}; + +//! gives the greatest divisor of num between 1 and max inclusive +template<typename T> static inline T greatest_divisor(T num, T max){ + for (T i = max; i > 1; i--) if (num%i == 0) return i; return 1; +} + +//! gives the least divisor of num between min and num exclusive +template<typename T> static inline T least_divisor(T num, T min){ + for (T i = min; i < num; i++) if (num%i == 0) return i; return 1; +} + +static clock_settings_type get_clock_settings(double rate){ + clock_settings_type cs; + cs.ref_clock_doubler = 2; //always doubling + cs.prescaler = 8; //set to 8 when input is under 2400 MHz -static const size_t r_counter = 1; -static const size_t a_counter = 0; -static const size_t b_counter = 20 / ref_clock_doubler; -static const size_t prescaler = 8; //set below with enum, set to 8 when input is under 2400 MHz -static const size_t vco_divider = 5; //set below with enum + //basic formulas used below: + //out_rate*X = ref_rate*Y + //X = i*ref_rate/gcd + //Y = i*out_rate/gcd + //X = chan_div * vco_div * R + //Y = P*B + A -static const size_t n_counter = prescaler * b_counter + a_counter; -static const size_t vco_clock_rate = ref_clock_rate/r_counter * n_counter; //between 1400 and 1800 MHz -static const double master_clock_rate = vco_clock_rate/vco_divider; + const boost::uint64_t out_rate = boost::uint64_t(rate); + const boost::uint64_t ref_rate = boost::uint64_t(cs.get_ref_rate()); + const size_t gcd = size_t(boost::math::gcd(ref_rate, out_rate)); -static const size_t fpga_clock_divider = size_t(master_clock_rate/64e6); -static const size_t codec_clock_divider = size_t(master_clock_rate/64e6); + for (size_t i = 1; i <= 100; i++){ + const size_t X = i*ref_rate/gcd; + const size_t Y = i*out_rate/gcd; + + //determine A and B (P is fixed) + cs.b_counter = Y/cs.prescaler; + cs.a_counter = Y - cs.b_counter*cs.prescaler; + + static const double vco_bound_pad = 100e6; + for ( //calculate an r divider that fits into the bounds of the vco + cs.r_counter = size_t(cs.get_n_counter()*cs.get_ref_rate()/(1800e6 - vco_bound_pad)); + cs.r_counter <= size_t(cs.get_n_counter()*cs.get_ref_rate()/(1400e6 + vco_bound_pad)) + and cs.r_counter > 0; cs.r_counter++ + ){ + + //determine chan_div and vco_div + //and fill in that order of preference + cs.chan_divider = greatest_divisor<size_t>(X/cs.r_counter, 32); + cs.vco_divider = greatest_divisor<size_t>(X/cs.chan_divider/cs.r_counter, 6); + + //avoid a vco divider of 1 (if possible) + if (cs.vco_divider == 1){ + cs.vco_divider = least_divisor<size_t>(cs.chan_divider, 2); + cs.chan_divider /= cs.vco_divider; + } + + if (CLOCK_SETTINGS_DEBUG){ + std::cout << "gcd " << gcd << std::endl; + std::cout << "X " << X << std::endl; + std::cout << "Y " << Y << std::endl; + std::cout << cs.to_pp_string() << std::endl; + } + + //filter limits on the counters + if (cs.vco_divider == 1) continue; + if (cs.r_counter >= (1<<14)) continue; + if (cs.b_counter == 2) continue; + if (cs.b_counter == 1 and cs.a_counter != 0) continue; + if (cs.b_counter >= (1<<13)) continue; + if (cs.a_counter >= (1<<6)) continue; + + std::cout << "USRP-E100 clock control: " << i << std::endl << cs.to_pp_string() << std::endl; + return cs; + } + } + + throw std::runtime_error(str(boost::format( + "USRP-E100 clock control: could not calculate settings for clock rate %fMHz" + ) % (rate/1e6))); +} /*********************************************************************** * Clock Control Implementation @@ -62,35 +170,70 @@ class usrp_e100_clock_ctrl_impl : public usrp_e100_clock_ctrl{ public: usrp_e100_clock_ctrl_impl(usrp_e100_iface::sptr iface){ _iface = iface; + _chan_rate = 0.0; + _out_rate = 0.0; //init the clock gen registers //Note: out0 should already be clocking the FPGA or this isnt going to work _ad9522_regs.sdo_active = ad9522_regs_t::SDO_ACTIVE_SDO_SDIO; - _ad9522_regs.enable_clock_doubler = 1; //enable ref clock doubler _ad9522_regs.enb_stat_eeprom_at_stat_pin = 0; //use status pin _ad9522_regs.status_pin_control = 0x1; //n divider _ad9522_regs.ld_pin_control = 0x00; //dld _ad9522_regs.refmon_pin_control = 0x12; //show ref2 + _ad9522_regs.lock_detect_counter = ad9522_regs_t::LOCK_DETECT_COUNTER_16CYC; - _ad9522_regs.enable_ref2 = 1; - _ad9522_regs.enable_ref1 = 0; - _ad9522_regs.select_ref = ad9522_regs_t::SELECT_REF_REF2; + this->use_internal_ref(); + + this->set_fpga_clock_rate(DEFAULT_OUTPUT_RATE); //initialize to something + + this->enable_test_clock(ENABLE_THE_TEST_OUT); + this->enable_rx_dboard_clock(false); + this->enable_tx_dboard_clock(false); + } + + ~usrp_e100_clock_ctrl_impl(void){ + this->enable_test_clock(ENABLE_THE_TEST_OUT); + this->enable_rx_dboard_clock(false); + this->enable_tx_dboard_clock(false); + } + + /*********************************************************************** + * Clock rate control: + * - set clock rate w/ internal VCO + * - set clock rate w/ external VCXO + **********************************************************************/ + void set_clock_settings_with_internal_vco(double rate){ + const clock_settings_type cs = get_clock_settings(rate); + + //set the rates to private variables so the implementation knows! + _chan_rate = cs.get_chan_rate(); + _out_rate = cs.get_out_rate(); - _ad9522_regs.set_r_counter(r_counter); - _ad9522_regs.a_counter = a_counter; - _ad9522_regs.set_b_counter(b_counter); + _ad9522_regs.enable_clock_doubler = (cs.ref_clock_doubler == 2)? 1 : 0; + + _ad9522_regs.set_r_counter(cs.r_counter); + _ad9522_regs.a_counter = cs.a_counter; + _ad9522_regs.set_b_counter(cs.b_counter); + UHD_ASSERT_THROW(cs.prescaler == 8); //assumes this below: _ad9522_regs.prescaler_p = ad9522_regs_t::PRESCALER_P_DIV8_9; _ad9522_regs.pll_power_down = ad9522_regs_t::PLL_POWER_DOWN_NORMAL; _ad9522_regs.cp_current = ad9522_regs_t::CP_CURRENT_1_2MA; - _ad9522_regs.vco_calibration_now = 1; //calibrate it! - _ad9522_regs.vco_divider = ad9522_regs_t::VCO_DIVIDER_DIV5; + _ad9522_regs.bypass_vco_divider = 0; + switch(cs.vco_divider){ + case 1: _ad9522_regs.vco_divider = ad9522_regs_t::VCO_DIVIDER_DIV1; break; + case 2: _ad9522_regs.vco_divider = ad9522_regs_t::VCO_DIVIDER_DIV2; break; + case 3: _ad9522_regs.vco_divider = ad9522_regs_t::VCO_DIVIDER_DIV3; break; + case 4: _ad9522_regs.vco_divider = ad9522_regs_t::VCO_DIVIDER_DIV4; break; + case 5: _ad9522_regs.vco_divider = ad9522_regs_t::VCO_DIVIDER_DIV5; break; + case 6: _ad9522_regs.vco_divider = ad9522_regs_t::VCO_DIVIDER_DIV6; break; + } _ad9522_regs.select_vco_or_clock = ad9522_regs_t::SELECT_VCO_OR_CLOCK_VCO; //setup fpga master clock _ad9522_regs.out0_format = ad9522_regs_t::OUT0_FORMAT_LVDS; - set_clock_divider(fpga_clock_divider, + set_clock_divider(cs.chan_divider, _ad9522_regs.divider0_low_cycles, _ad9522_regs.divider0_high_cycles, _ad9522_regs.divider0_bypass @@ -98,52 +241,69 @@ public: //setup codec clock _ad9522_regs.out3_format = ad9522_regs_t::OUT3_FORMAT_LVDS; - set_clock_divider(codec_clock_divider, + set_clock_divider(cs.chan_divider, _ad9522_regs.divider1_low_cycles, _ad9522_regs.divider1_high_cycles, _ad9522_regs.divider1_bypass ); - //setup test clock (same divider as codec clock) - _ad9522_regs.out4_format = ad9522_regs_t::OUT4_FORMAT_CMOS; - _ad9522_regs.out4_cmos_configuration = (enable_test_clock)? - ad9522_regs_t::OUT4_CMOS_CONFIGURATION_A_ON : - ad9522_regs_t::OUT4_CMOS_CONFIGURATION_OFF; + this->send_all_regs(); + calibrate_now(); + } - //setup a list of register ranges to write - typedef std::pair<boost::uint16_t, boost::uint16_t> range_t; - static const std::vector<range_t> ranges = boost::assign::list_of - (range_t(0x000, 0x000)) (range_t(0x010, 0x01F)) - (range_t(0x0F0, 0x0FD)) (range_t(0x190, 0x19B)) - (range_t(0x1E0, 0x1E1)) (range_t(0x230, 0x230)) - ; + void set_clock_settings_with_external_vcxo(double rate){ + //set the rates to private variables so the implementation knows! + _chan_rate = rate; + _out_rate = rate; - //write initial register values and latch/update - BOOST_FOREACH(const range_t &range, ranges){ - for(boost::uint16_t addr = range.first; addr <= range.second; addr++){ - this->send_reg(addr); - } - } - this->latch_regs(); - //test read: - //boost::uint32_t reg = _ad9522_regs.get_read_reg(0x01b); - //boost::uint32_t result = _iface->transact_spi( - // UE_SPI_SS_AD9522, - // spi_config_t::EDGE_RISE, - // reg, 24, true /*no*/ - //); - //std::cout << "result " << std::hex << result << std::endl; - this->enable_rx_dboard_clock(false); - this->enable_tx_dboard_clock(false); + _ad9522_regs.enable_clock_doubler = 1; //doubler always on + const double ref_rate = REFERENCE_INPUT_RATE*2; + + //bypass prescaler such that N = B + long gcd = boost::math::gcd(long(ref_rate), long(rate)); + _ad9522_regs.set_r_counter(int(ref_rate/gcd)); + _ad9522_regs.a_counter = 0; + _ad9522_regs.set_b_counter(int(rate/gcd)); + _ad9522_regs.prescaler_p = ad9522_regs_t::PRESCALER_P_DIV1; + + //setup external vcxo + _ad9522_regs.pll_power_down = ad9522_regs_t::PLL_POWER_DOWN_NORMAL; + _ad9522_regs.cp_current = ad9522_regs_t::CP_CURRENT_1_2MA; + _ad9522_regs.bypass_vco_divider = 1; + _ad9522_regs.select_vco_or_clock = ad9522_regs_t::SELECT_VCO_OR_CLOCK_EXTERNAL; + + //setup fpga master clock + _ad9522_regs.out0_format = ad9522_regs_t::OUT0_FORMAT_LVDS; + _ad9522_regs.divider0_bypass = 1; + + //setup codec clock + _ad9522_regs.out3_format = ad9522_regs_t::OUT3_FORMAT_LVDS; + _ad9522_regs.divider1_bypass = 1; + + this->send_all_regs(); } - ~usrp_e100_clock_ctrl_impl(void){ - this->enable_rx_dboard_clock(false); - this->enable_tx_dboard_clock(false); + void set_fpga_clock_rate(double rate){ + if (_out_rate == rate) return; + if (rate == 61.44e6) set_clock_settings_with_external_vcxo(rate); + else set_clock_settings_with_internal_vco(rate); } double get_fpga_clock_rate(void){ - return master_clock_rate/fpga_clock_divider; + return this->_out_rate; + } + + /*********************************************************************** + * Special test clock output + **********************************************************************/ + void enable_test_clock(bool enb){ + //setup test clock (same divider as codec clock) + _ad9522_regs.out4_format = ad9522_regs_t::OUT4_FORMAT_CMOS; + _ad9522_regs.out4_cmos_configuration = (enb)? + ad9522_regs_t::OUT4_CMOS_CONFIGURATION_A_ON : + ad9522_regs_t::OUT4_CMOS_CONFIGURATION_OFF; + this->send_reg(0x0F0); + this->latch_regs(); } /*********************************************************************** @@ -161,13 +321,13 @@ public: std::vector<double> get_rx_dboard_clock_rates(void){ std::vector<double> rates; for(size_t div = 1; div <= 16+16; div++) - rates.push_back(master_clock_rate/div); + rates.push_back(this->_chan_rate/div); return rates; } void set_rx_dboard_clock_rate(double rate){ assert_has(get_rx_dboard_clock_rates(), rate, "rx dboard clock rate"); - size_t divider = size_t(master_clock_rate/rate); + size_t divider = size_t(this->_chan_rate/rate); //set the divider registers set_clock_divider(divider, _ad9522_regs.divider3_low_cycles, @@ -197,7 +357,7 @@ public: void set_tx_dboard_clock_rate(double rate){ assert_has(get_tx_dboard_clock_rates(), rate, "tx dboard clock rate"); - size_t divider = size_t(master_clock_rate/rate); + size_t divider = size_t(this->_chan_rate/rate); //set the divider registers set_clock_divider(divider, _ad9522_regs.divider2_low_cycles, @@ -238,6 +398,8 @@ public: private: usrp_e100_iface::sptr _iface; ad9522_regs_t _ad9522_regs; + double _out_rate; //rate at the fpga and codec + double _chan_rate; //rate before final dividers void latch_regs(void){ _ad9522_regs.io_update = 1; @@ -253,6 +415,46 @@ private: reg, 24, false /*no rb*/ ); } + + void calibrate_now(void){ + //vco calibration routine: + _ad9522_regs.vco_calibration_now = 0; + this->send_reg(0x18); + this->latch_regs(); + _ad9522_regs.vco_calibration_now = 1; + this->send_reg(0x18); + this->latch_regs(); + //wait for calibration done: + static const boost::uint8_t addr = 0x01F; + for (size_t ms10 = 0; ms10 < 100; ms10++){ + boost::uint32_t reg = _iface->transact_spi( + UE_SPI_SS_AD9522, spi_config_t::EDGE_RISE, + _ad9522_regs.get_read_reg(addr), 24, true /*rb*/ + ); + _ad9522_regs.set_reg(addr, reg); + if (_ad9522_regs.vco_calibration_finished) return; + boost::this_thread::sleep(boost::posix_time::milliseconds(10)); + } + std::cerr << "USRP-E100 clock control: VCO calibration timeout" << std::endl; + } + + void send_all_regs(void){ + //setup a list of register ranges to write + typedef std::pair<boost::uint16_t, boost::uint16_t> range_t; + static const std::vector<range_t> ranges = boost::assign::list_of + (range_t(0x000, 0x000)) (range_t(0x010, 0x01F)) + (range_t(0x0F0, 0x0FD)) (range_t(0x190, 0x19B)) + (range_t(0x1E0, 0x1E1)) (range_t(0x230, 0x230)) + ; + + //write initial register values and latch/update + BOOST_FOREACH(const range_t &range, ranges){ + for(boost::uint16_t addr = range.first; addr <= range.second; addr++){ + this->send_reg(addr); + } + } + this->latch_regs(); + } }; /*********************************************************************** |