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-rw-r--r--host/lib/usrp/b100/clock_ctrl.cpp525
1 files changed, 525 insertions, 0 deletions
diff --git a/host/lib/usrp/b100/clock_ctrl.cpp b/host/lib/usrp/b100/clock_ctrl.cpp
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+++ b/host/lib/usrp/b100/clock_ctrl.cpp
@@ -0,0 +1,525 @@
+//
+// 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
+// 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;
+
+ UHD_MSG(status) << "USRP-B100 clock control: " << i << std::endl << cs.to_pp_string() << std::endl;
+ return cs;
+ }
+ }
+
+ throw uhd::runtime_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(b100_iface::sptr iface, double master_clock_rate){
+ _iface = iface;
+ _chan_rate = 0.0;
+ _out_rate = 0.0;
+
+ //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);
+ _iface->poke32(B100_REG_TIME64_TPS, boost::uint32_t(get_fpga_clock_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_CMOS;
+ _ad9522_regs.out9_cmos_configuration = (enb)?
+ ad9522_regs_t::OUT9_CMOS_CONFIGURATION_B_ON :
+ ad9522_regs_t::OUT9_CMOS_CONFIGURATION_OFF;
+ 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_CMOS;
+ _ad9522_regs.out6_cmos_configuration = (enb)?
+ ad9522_regs_t::OUT6_CMOS_CONFIGURATION_B_ON :
+ ad9522_regs_t::OUT6_CMOS_CONFIGURATION_OFF;
+ 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();
+ }
+
+private:
+ b100_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->get_fx2_i2c_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->get_fx2_i2c_iface().write_i2c(0x5C, buf);
+
+ buf = _iface->get_fx2_i2c_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(b100_iface::sptr iface, double master_clock_rate){
+ return sptr(new b100_clock_ctrl_impl(iface, master_clock_rate));
+}