diff options
Diffstat (limited to 'host/lib/usrp/b100/clock_ctrl.cpp')
| -rw-r--r-- | host/lib/usrp/b100/clock_ctrl.cpp | 536 |
1 files changed, 536 insertions, 0 deletions
diff --git a/host/lib/usrp/b100/clock_ctrl.cpp b/host/lib/usrp/b100/clock_ctrl.cpp new file mode 100644 index 000000000..cbe6c40a0 --- /dev/null +++ b/host/lib/usrp/b100/clock_ctrl.cpp @@ -0,0 +1,536 @@ +// +// Copyright 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 +// 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 <http://www.gnu.org/licenses/>. +// + +#include "clock_ctrl.hpp" +#include "ad9522_regs.hpp" +#include <uhd/utils/log.hpp> +#include <uhd/utils/msg.hpp> +#include <uhd/exception.hpp> +#include <uhd/utils/assert_has.hpp> +#include <uhd/utils/safe_call.hpp> +#include <boost/cstdint.hpp> +#include "b100_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> + +using namespace uhd; + +/*********************************************************************** + * Constants + **********************************************************************/ +static const bool ENABLE_THE_TEST_OUT = true; +static const double REFERENCE_INPUT_RATE = 10e6; + +/*********************************************************************** + * 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 +){ + high = divider/2 - 1; + low = divider - high - 2; + bypass = (divider == 1)? 1 : 0; +} + +/*********************************************************************** + * Clock rate calculation stuff: + * Using the internal VCO between 1400 and 1800 MHz + **********************************************************************/ +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 + + //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 + + 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)); + + 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; + } + + UHD_LOGV(always) + << "gcd " << gcd << std::endl + << "X " << X << std::endl + << "Y " << Y << std::endl + << 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; + if (cs.get_vco_rate() > 1800e6 - vco_bound_pad) continue; + if (cs.get_vco_rate() < 1400e6 + vco_bound_pad) continue; + if (cs.get_out_rate() != rate) continue; + + UHD_MSG(status) << "USRP-B100 clock control: " << i << std::endl << cs.to_pp_string() << std::endl; + return cs; + } + } + + throw uhd::value_error(str(boost::format( + "USRP-B100 clock control: could not calculate settings for clock rate %fMHz" + ) % (rate/1e6))); +} + +/*********************************************************************** + * Clock Control Implementation + **********************************************************************/ +class b100_clock_ctrl_impl : public b100_clock_ctrl{ +public: + b100_clock_ctrl_impl(i2c_iface::sptr iface, double master_clock_rate){ + _iface = iface; + _chan_rate = 0.0; + _out_rate = 0.0; + + //perform soft-reset + _ad9522_regs.soft_reset = 1; + this->send_reg(0x000); + this->latch_regs(); + _ad9522_regs.soft_reset = 0; + + //init the clock gen registers + _ad9522_regs.sdo_active = ad9522_regs_t::SDO_ACTIVE_SDO_SDIO; + _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; + + this->use_internal_ref(); + + this->set_fpga_clock_rate(master_clock_rate); //initialize to something + + this->enable_fpga_clock(true); + this->enable_test_clock(ENABLE_THE_TEST_OUT); + this->enable_rx_dboard_clock(false); + this->enable_tx_dboard_clock(false); + } + + ~b100_clock_ctrl_impl(void){ + UHD_SAFE_CALL( + this->enable_test_clock(ENABLE_THE_TEST_OUT); + this->enable_rx_dboard_clock(false); + this->enable_tx_dboard_clock(false); + //this->enable_fpga_clock(false); //FIXME + ) + } + + /*********************************************************************** + * 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.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.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(cs.chan_divider, + _ad9522_regs.divider0_low_cycles, + _ad9522_regs.divider0_high_cycles, + _ad9522_regs.divider0_bypass + ); + + //setup codec clock + _ad9522_regs.out3_format = ad9522_regs_t::OUT3_FORMAT_LVDS; + set_clock_divider(cs.chan_divider, + _ad9522_regs.divider1_low_cycles, + _ad9522_regs.divider1_high_cycles, + _ad9522_regs.divider1_bypass + ); + + this->send_all_regs(); + calibrate_now(); + } + + 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; + + _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(); + } + + 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); + //clock rate changed! update dboard clocks and FPGA ticks per second + set_rx_dboard_clock_rate(rate); + set_tx_dboard_clock_rate(rate); + } + + double get_fpga_clock_rate(void){ + return this->_out_rate; + } + + /*********************************************************************** + * FPGA clock enable + **********************************************************************/ + void enable_fpga_clock(bool enb){ + _ad9522_regs.out0_format = ad9522_regs_t::OUT0_FORMAT_LVDS; + _ad9522_regs.out0_lvds_power_down = !enb; + this->send_reg(0x0F0); + this->latch_regs(); + } + + /*********************************************************************** + * 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(0x0F4); + this->latch_regs(); + } + + /*********************************************************************** + * RX Dboard Clock Control (output 9, divider 3) + **********************************************************************/ + void enable_rx_dboard_clock(bool enb){ + _ad9522_regs.out9_format = ad9522_regs_t::OUT9_FORMAT_LVDS; + _ad9522_regs.out9_lvds_power_down = !enb; + this->send_reg(0x0F9); + this->latch_regs(); + } + + 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(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"); + _rx_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, + _ad9522_regs.divider3_high_cycles, + _ad9522_regs.divider3_bypass + ); + this->send_reg(0x199); + this->send_reg(0x19a); + this->soft_sync(); + } + + double get_rx_clock_rate(void){ + return _rx_clock_rate; + } + + /*********************************************************************** + * TX Dboard Clock Control (output 6, divider 2) + **********************************************************************/ + void enable_tx_dboard_clock(bool enb){ + _ad9522_regs.out6_format = ad9522_regs_t::OUT6_FORMAT_LVDS; + _ad9522_regs.out6_lvds_power_down = !enb; + this->send_reg(0x0F6); + this->latch_regs(); + } + + std::vector<double> get_tx_dboard_clock_rates(void){ + return get_rx_dboard_clock_rates(); //same master clock, same dividers... + } + + void set_tx_dboard_clock_rate(double rate){ + assert_has(get_tx_dboard_clock_rates(), rate, "tx dboard clock rate"); + _tx_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, + _ad9522_regs.divider2_high_cycles, + _ad9522_regs.divider2_bypass + ); + this->send_reg(0x196); + this->send_reg(0x197); + this->soft_sync(); + } + + double get_tx_clock_rate(void){ + return _tx_clock_rate; + } + + /*********************************************************************** + * Clock reference control + **********************************************************************/ + void use_internal_ref(void) { + _ad9522_regs.enable_ref2 = 1; + _ad9522_regs.enable_ref1 = 0; + _ad9522_regs.select_ref = ad9522_regs_t::SELECT_REF_REF2; + _ad9522_regs.enb_auto_ref_switchover = ad9522_regs_t::ENB_AUTO_REF_SWITCHOVER_MANUAL; + this->send_reg(0x01C); + this->latch_regs(); + } + + void use_external_ref(void) { + _ad9522_regs.enable_ref2 = 0; + _ad9522_regs.enable_ref1 = 1; + _ad9522_regs.select_ref = ad9522_regs_t::SELECT_REF_REF1; + _ad9522_regs.enb_auto_ref_switchover = ad9522_regs_t::ENB_AUTO_REF_SWITCHOVER_MANUAL; + this->send_reg(0x01C); + this->latch_regs(); + } + + void use_auto_ref(void) { + _ad9522_regs.enable_ref2 = 1; + _ad9522_regs.enable_ref1 = 1; + _ad9522_regs.select_ref = ad9522_regs_t::SELECT_REF_REF1; + _ad9522_regs.enb_auto_ref_switchover = ad9522_regs_t::ENB_AUTO_REF_SWITCHOVER_AUTO; + this->send_reg(0x01C); + this->latch_regs(); + } + + bool get_locked(void){ + static const boost::uint8_t addr = 0x01F; + boost::uint32_t reg = this->read_reg(addr); + _ad9522_regs.set_reg(addr, reg); + return _ad9522_regs.digital_lock_detect != 0; + } + +private: + i2c_iface::sptr _iface; + ad9522_regs_t _ad9522_regs; + double _out_rate; //rate at the fpga and codec + double _chan_rate; //rate before final dividers + double _rx_clock_rate, _tx_clock_rate; + + void latch_regs(void){ + _ad9522_regs.io_update = 1; + this->send_reg(0x232); + } + + void send_reg(boost::uint16_t addr){ + boost::uint32_t reg = _ad9522_regs.get_write_reg(addr); + UHD_LOGV(often) << "clock control write reg: " << std::hex << reg << std::endl; + byte_vector_t buf; + buf.push_back(boost::uint8_t(reg >> 16)); + buf.push_back(boost::uint8_t(reg >> 8)); + buf.push_back(boost::uint8_t(reg & 0xff)); + + _iface->write_i2c(0x5C, buf); + } + + boost::uint8_t read_reg(boost::uint16_t addr){ + byte_vector_t buf; + buf.push_back(boost::uint8_t(addr >> 8)); + buf.push_back(boost::uint8_t(addr & 0xff)); + _iface->write_i2c(0x5C, buf); + + buf = _iface->read_i2c(0x5C, 1); + + return boost::uint32_t(buf[0] & 0xFF); + } + + 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::this_thread::sleep(boost::posix_time::milliseconds(10)); + boost::uint32_t reg = read_reg(addr); + _ad9522_regs.set_reg(addr, reg); + if (_ad9522_regs.vco_calibration_finished) goto wait_for_ld; + } + UHD_MSG(error) << "USRP-B100 clock control: VCO calibration timeout" << std::endl; + wait_for_ld: + //wait for digital lock detect: + for (size_t ms10 = 0; ms10 < 100; ms10++){ + boost::this_thread::sleep(boost::posix_time::milliseconds(10)); + boost::uint32_t reg = read_reg(addr); + _ad9522_regs.set_reg(addr, reg); + if (_ad9522_regs.digital_lock_detect) return; + } + UHD_MSG(error) << "USRP-B100 clock control: lock detection timeout" << std::endl; + } + + void soft_sync(void){ + _ad9522_regs.soft_sync = 1; + this->send_reg(0x230); + this->latch_regs(); + _ad9522_regs.soft_sync = 0; + this->send_reg(0x230); + this->latch_regs(); + } + + 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(); + } +}; + +/*********************************************************************** + * Clock Control Make + **********************************************************************/ +b100_clock_ctrl::sptr b100_clock_ctrl::make(i2c_iface::sptr iface, double master_clock_rate){ + return sptr(new b100_clock_ctrl_impl(iface, master_clock_rate)); +} |