uhd: Added LMX2592 driver

2 files changed, 472 insertions, 0 deletions

diff --git a/host/lib/usrp/common/CMakeLists.txt b/host/lib/usrp/common/CMakeLists.txt
index 9e27fb880..082a047e7 100644
--- a/host/lib/usrp/common/CMakeLists.txt
+++ b/host/lib/usrp/common/CMakeLists.txt
@@ -29,6 +29,7 @@ LIBUHD_APPEND_SOURCES(
     ${CMAKE_CURRENT_SOURCE_DIR}/adf4001_ctrl.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/adf435x.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/adf535x.cpp
+    ${CMAKE_CURRENT_SOURCE_DIR}/lmx2592.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/apply_corrections.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/validate_subdev_spec.cpp
     ${CMAKE_CURRENT_SOURCE_DIR}/recv_packet_demuxer.cpp
diff --git a/host/lib/usrp/common/lmx2592.cpp b/host/lib/usrp/common/lmx2592.cpp
new file mode 100644
index 000000000..3f71fb04c
--- /dev/null
+++ b/host/lib/usrp/common/lmx2592.cpp
@@ -0,0 +1,471 @@
+//
+// Copyright 2018, 2017 Ettus Research, A National Instruments Company
+//
+// SPDX-License-Identifier: GPL-3.0-or-later
+//
+
+#include "lmx2592_regs.hpp"
+#include <uhdlib/usrp/common/lmx2592.hpp>
+#include <uhdlib/utils/narrow.hpp>
+#include <boost/math/common_factor_rt.hpp>
+#include <chrono>
+#include <cmath>
+#include <iomanip>
+#include <iostream>
+
+using namespace uhd;
+
+namespace {
+constexpr double LMX2592_DOUBLER_MAX_REF_FREQ = 60e6;
+constexpr double LMX2592_MAX_FREQ_PFD = 125e6;
+
+constexpr double LMX2592_MIN_REF_FREQ = 5e6;
+constexpr double LMX2592_MAX_REF_FREQ = 1400e6;
+
+constexpr double LMX2592_MAX_OUT_FREQ = 9.8e9;
+constexpr double LMX2592_MIN_OUT_FREQ = 20e6;
+
+constexpr double LMX2592_MIN_VCO_FREQ = 3.55e9;
+constexpr double LMX2592_MAX_VCO_FREQ = 7.1e9;
+
+constexpr double LMX2592_MAX_DOUBLER_INPUT_FREQ = 200e6;
+constexpr double LMX2592_MAX_MULT_OUT_FREQ = 250e6;
+constexpr double LMX2592_MAX_MULT_INPUT_FREQ = 70e6;
+constexpr double LMX2592_MAX_POSTR_DIV_OUT_FREQ = 125e6;
+
+constexpr int MAX_N_DIVIDER = 4095;
+
+constexpr int MAX_MASH_ORDER = 4;
+constexpr std::array<int, MAX_MASH_ORDER + 1> LMX2592_MIN_N_DIV = {
+    9, 11, 16, 18, 30
+}; // includes int-N
+
+constexpr int NUM_DIVIDERS = 14;
+constexpr std::array<int, NUM_DIVIDERS> LMX2592_CHDIV_DIVIDERS = { 1,  2,  3,  4,  6,  8,   12,
+                                                                   16, 24, 32, 64, 96, 128, 192 };
+const std::array<double, NUM_DIVIDERS> LMX2592_CHDIV_MIN_FREQ = {
+    3550e6,   1775e6,   1183.33e6, 887.5e6, 591.67e6, 443.75e6, 295.83e6,
+    221.88e6, 147.92e6, 110.94e6,  55.47e6, 36.98e6,  27.73e6,  20e6
+};
+constexpr std::array<double, NUM_DIVIDERS> LMX2592_CHDIV_MAX_FREQ = {
+    6000e6,   3550.0e6, 2366.67e6, 1775.00e6, 1183.33, 887.50e6, 591.67e6,
+    443.75e6, 295.83e6, 221.88e6,  110.94e6,  73.96e6, 55.47e6,  36.98
+};
+constexpr int NUM_CHDIV_STAGES = 3;
+constexpr std::array<std::array<int, NUM_CHDIV_STAGES>, NUM_DIVIDERS> LMX2592_CHDIV_SEGS = {
+    { { 1, 1, 1 },
+      { 2, 1, 1 },
+      { 3, 1, 1 },
+      { 2, 2, 1 },
+      { 3, 2, 1 },
+      { 2, 4, 1 },
+      { 2, 6, 1 },
+      { 2, 8, 1 },
+      { 3, 8, 1 },
+      { 2, 8, 2 },
+      { 2, 8, 4 },
+      { 2, 8, 6 },
+      { 2, 8, 8 },
+      { 3, 8, 8 } }
+};
+
+constexpr int SPI_ADDR_SHIFT = 16;
+constexpr int SPI_ADDR_MASK = 0x7f;
+constexpr int SPI_READ_FLAG = 1 << 23;
+}
+
+class lmx2592_impl : public lmx2592_iface {
+public:
+    explicit lmx2592_impl(write_spi_t write_fn, read_spi_t read_fn)
+        : _write_fn([write_fn](const uint8_t addr, const uint16_t data) {
+              const uint32_t spi_transaction =
+                  0 | ((addr & SPI_ADDR_MASK) << SPI_ADDR_SHIFT) | data;
+              write_fn(spi_transaction);
+          }),
+          _read_fn([read_fn](const uint8_t addr) {
+              const uint32_t spi_transaction =
+                  SPI_READ_FLAG | ((addr & SPI_ADDR_MASK) << SPI_ADDR_SHIFT);
+              return read_fn(spi_transaction);
+          }),
+          _regs(),
+          _rewrite_regs(true) {
+        UHD_LOG_TRACE("LMX2592", "Initializing Synthesizer");
+
+        // Soft Reset
+        _regs.reset = 1;
+        UHD_LOG_TRACE("LMX2592", "Resetting LMX");
+        _write_fn(_regs.ADDR_R0, _regs.get_reg(_regs.ADDR_R0));
+
+        // The bit is cleared on the synth during the reset
+        _regs.reset = 0;
+
+        // Enable SPI Readback
+        _regs.muxout_sel = lmx2592_regs_t::muxout_sel_t::MUXOUT_SEL_READBACK;
+        UHD_LOG_TRACE("LMX2592", "Enabling SPI Readback");
+        _write_fn(_regs.ADDR_R0, _regs.get_reg(_regs.ADDR_R0));
+
+        // Test Write/Read
+        const auto random_number = // Derived from current time
+            static_cast<uint16_t>(
+                std::chrono::system_clock::to_time_t(std::chrono::system_clock::now()) & 0x0FFF);
+        _write_fn(_regs.ADDR_R40, random_number);
+        const auto readback = _read_fn(_regs.ADDR_R40);
+        if (readback == random_number) {
+            UHD_LOG_TRACE("LMX2592", "Register loopback test passed");
+        } else {
+            throw runtime_error(
+                str(boost::format(
+                        "LMX2592 register loopback test failed. Expected 0x%04X, Read 0x%04X") %
+                    random_number % readback));
+        }
+
+        // Set register values where driver defaults differ from the datasheet values
+        _regs.acal_enable = 0;
+        _regs.fcal_enable = 0;
+        _regs.cal_clk_div = 0;
+        _regs.vco_idac_ovr = 1;
+        _regs.cp_idn = 12;
+        _regs.cp_iup = 12;
+        _regs.vco_idac = 350;
+        _regs.mash_ditherer = 1;
+        _regs.outa_mux = lmx2592_regs_t::outa_mux_t::OUTA_MUX_VCO;
+        _regs.fcal_fast = 1;
+
+        // Write default register values, ensures register copy is synchronized
+        _rewrite_regs = true;
+        commit();
+
+        _regs.fcal_enable = 1;
+        commit();
+    }
+
+    ~lmx2592_impl() override { UHD_SAFE_CALL(_regs.powerdown = 1; commit();) }
+
+    double set_frequency(const double target_freq) override {
+
+        // Enforce LMX frequency limits
+        if (target_freq < LMX2592_MIN_OUT_FREQ or target_freq > LMX2592_MAX_OUT_FREQ) {
+            throw runtime_error("Requested frequency is out of the supported range");
+        }
+
+        // Find the largest possible divider
+        auto output_divider_index = 0;
+        for (auto limit : LMX2592_CHDIV_MIN_FREQ) {
+            if (target_freq < limit) {
+                output_divider_index++;
+            } else {
+                break;
+            }
+        }
+        const auto output_divider = LMX2592_CHDIV_DIVIDERS[output_divider_index];
+        _set_chdiv_values(output_divider_index);
+
+        // Setup input signal path and PLL loop
+        const int vco_multiplier = target_freq > LMX2592_MAX_VCO_FREQ ? 2 : 1;
+
+        const auto target_vco_freq = target_freq * output_divider;
+        const auto core_vco_freq = target_vco_freq / vco_multiplier;
+
+        double input_freq = _ref_freq;
+
+        // Input Doubler stage
+        if (input_freq <= LMX2592_MAX_DOUBLER_INPUT_FREQ) {
+            _regs.osc_doubler = 1;
+            input_freq *= 2;
+        } else {
+            _regs.osc_doubler = 0;
+        }
+
+        // Pre-R divider
+        _regs.pll_r_pre =
+            narrow_cast<uint16_t>(std::ceil(input_freq / LMX2592_MAX_MULT_INPUT_FREQ));
+        input_freq /= _regs.pll_r_pre;
+
+        // Multiplier
+        _regs.mult = narrow_cast<uint8_t>(std::floor(LMX2592_MAX_MULT_OUT_FREQ / input_freq));
+        input_freq *= _regs.mult;
+
+        // Post R divider
+        _regs.pll_r = narrow_cast<uint8_t>(std::ceil(input_freq / LMX2592_MAX_POSTR_DIV_OUT_FREQ));
+
+        // Default to divide by 2, will be increased later if N exceeds it's limit
+        int prescaler = 2;
+        _regs.pll_n_pre = lmx2592_regs_t::pll_n_pre_t::PLL_N_PRE_DIVIDE_BY_2;
+
+        const int min_n_divider = LMX2592_MIN_N_DIV[_regs.mash_order];
+        double pfd_freq = input_freq / _regs.pll_r;
+        while (pfd_freq * (prescaler + min_n_divider) / vco_multiplier > core_vco_freq) {
+            _regs.pll_r++;
+            pfd_freq = input_freq / _regs.pll_r;
+        }
+
+        const auto spur_dodging_enable = false;
+        const double min_vco_step_size = spur_dodging_enable ? 2e6 : 1;
+
+        auto fden = static_cast<uint32_t>(std::floor(pfd_freq * prescaler / min_vco_step_size));
+        _regs.pll_den_lsb = narrow_cast<uint16_t>(fden);
+        _regs.pll_den_msb = narrow_cast<uint16_t>(fden >> 16);
+
+        auto mash_seed = static_cast<uint32_t>(fden / 2);
+        _regs.mash_seed_lsb = narrow_cast<uint16_t>(mash_seed);
+        _regs.mash_seed_msb = narrow_cast<uint16_t>(mash_seed >> 16);
+
+        // Calculate N and Fnum
+        const auto N_dot_F = target_vco_freq / (pfd_freq * prescaler);
+        auto N = static_cast<uint16_t>(std::floor(N_dot_F));
+        if (N > MAX_N_DIVIDER) {
+            _regs.pll_n_pre = lmx2592_regs_t::pll_n_pre_t::PLL_N_PRE_DIVIDE_BY_4;
+            N /= 2;
+        }
+        const auto frac = N_dot_F - N;
+        const auto fnum = static_cast<uint32_t>(std::round(frac * fden));
+
+        _regs.pll_n = N;
+        _regs.pll_num_lsb = narrow_cast<uint16_t>(fnum);
+        _regs.pll_num_msb = narrow_cast<uint16_t>(fnum >> 16);
+
+        // Calculate actual Fcore_vco, Fvco, F_lo frequencies
+        const auto actual_fvco = pfd_freq * prescaler * (N + double(fnum) / double(fden));
+        const auto actual_fcore_vco = actual_fvco / vco_multiplier;
+        const auto actual_f_lo = actual_fcore_vco * vco_multiplier / output_divider;
+
+        UHD_LOGGER_TRACE("LMX2592") << "Tuned to " << actual_f_lo;
+        commit();
+
+        // Run Frequency Calibration
+        _regs.fcal_enable = 1;
+        commit();
+
+        UHD_LOGGER_TRACE("LMX2592")
+            << "PLL lock status: " << (get_lock_status() ? "Locked" : "Unlocked");
+
+        return actual_f_lo;
+    }
+
+    void set_mash_order(const mash_order_t mash_order) override {
+        if (mash_order == mash_order_t::INT_N) {
+            _regs.mash_order = lmx2592_regs_t::mash_order_t::MASH_ORDER_INT_MODE;
+
+        } else if (mash_order == mash_order_t::FIRST) {
+            _regs.mash_order = lmx2592_regs_t::mash_order_t::MASH_ORDER_FIRST;
+
+        } else if (mash_order == mash_order_t::SECOND) {
+            _regs.mash_order = lmx2592_regs_t::mash_order_t::MASH_ORDER_SECOND;
+
+        } else if (mash_order == mash_order_t::THIRD) {
+            _regs.mash_order = lmx2592_regs_t::mash_order_t::MASH_ORDER_THIRD;
+
+        } else if (mash_order == mash_order_t::FOURTH) {
+            _regs.mash_order = lmx2592_regs_t::mash_order_t::MASH_ORDER_FOURTH;
+        }
+    }
+
+    void set_reference_frequency(const double ref_freq) override {
+        if (ref_freq < LMX2592_MIN_REF_FREQ or ref_freq > LMX2592_MAX_REF_FREQ) {
+            throw std::runtime_error("Reference frequency is out of bounds for the LMX2592");
+        }
+
+        _ref_freq = ref_freq;
+    }
+
+    void set_output_power(const output_t output, const unsigned int power) override {
+        UHD_LOGGER_TRACE("LMX2592")
+            << "Set output: " << (output == RF_OUTPUT_A ? "A" : "B") << " to power " << power;
+
+        const auto MAX_POWER = 63;
+        if (power > MAX_POWER) {
+            UHD_LOGGER_ERROR("LMX2592")
+                << "Requested power level of " << power << " exceeds maximum of " << MAX_POWER;
+            return;
+        }
+
+        if (output == RF_OUTPUT_A) {
+            _regs.outa_power = power;
+        } else {
+            _regs.outb_power = power;
+        }
+
+        commit();
+    }
+
+    void set_output_enable(const output_t output, const bool enable) override {
+        UHD_LOGGER_TRACE("LMX2592") << "Set output " << (output == RF_OUTPUT_A ? "A" : "B")
+                                    << " to " << (enable ? "On" : "Off");
+
+        if (enable) {
+            _regs.chdiv_dist_pd = 0;
+
+            if (output == RF_OUTPUT_A) {
+                _regs.outa_pd = 0;
+
+            } else {
+                _regs.outb_pd = 0;
+            }
+
+        } else {
+            if (output == RF_OUTPUT_A) {
+                _regs.outa_pd = 1;
+                _regs.vco_dista_pd = 1;
+                _regs.chdiv_dista_en = 0;
+
+            } else {
+                _regs.outb_pd = 1;
+                _regs.vco_distb_pd = 1;
+                _regs.chdiv_distb_en = 0;
+            }
+        }
+
+        // If both channels are disabled
+        if (_regs.outa_pd == 1 and _regs.outb_pd == 1) {
+            _regs.chdiv_dist_pd = 1;
+        }
+
+        commit();
+    }
+
+    bool get_lock_status() override {
+        // MUXOUT is shared between Lock Detect and SPI Readback
+        _regs.muxout_sel = lmx2592_regs_t::muxout_sel_t::MUXOUT_SEL_LOCK_DETECT;
+        commit();
+
+        // The SPI MISO is now being driven by lock detect
+        // If the PLL is locked we expect to read 0xFFFF from any read, else 0x0000
+        const auto value_read = _read_fn(_regs.ADDR_R0);
+        const auto lock_status = (value_read == 0xFFFF);
+
+        UHD_LOG_TRACE(
+            "LMX2592",
+            str(boost::format("Read Lock status: 0x%04X") % static_cast<unsigned int>(value_read)));
+
+        // Restore ability to read registers
+        _regs.muxout_sel = lmx2592_regs_t::muxout_sel_t::MUXOUT_SEL_READBACK;
+        commit();
+
+        return lock_status;
+    }
+
+    void commit() override {
+        UHD_LOGGER_DEBUG("LMX2592")
+            << "Storing register cache " << (_rewrite_regs ? "completely" : "selectively")
+            << " to LMX via SPI...";
+        const auto changed_addrs =
+            _rewrite_regs ? _regs.get_all_addrs() : _regs.get_changed_addrs<size_t>();
+
+        for (const auto addr : changed_addrs) {
+            _write_fn(addr, _regs.get_reg(addr));
+            UHD_LOGGER_TRACE("LMX2592")
+                << "Register " << std::setw(2) << static_cast<unsigned int>(addr) << ": 0x"
+                << std::hex << std::uppercase << std::setw(4) << std::setfill('0')
+                << static_cast<unsigned int>(_regs.get_reg(addr));
+        }
+
+        _regs.save_state();
+        UHD_LOG_DEBUG("LMX2592",
+                      "Writing registers complete: "
+                      "Updated "
+                          << changed_addrs.size()
+                          << " registers.");
+
+        _rewrite_regs = false;
+    }
+
+private: // Members
+    //! Write functor: Take address / data pair, craft SPI transaction
+    using write_fn_t = std::function<void(uint8_t, uint16_t)>;
+    //! Read functor: Return value given address
+    using read_fn_t = std::function<uint16_t(uint8_t)>;
+
+    write_fn_t _write_fn;
+    read_fn_t _read_fn;
+    lmx2592_regs_t _regs;
+    bool _rewrite_regs;
+    double _ref_freq;
+
+    void _set_chdiv_values(const int output_divider_index) {
+
+        // Configure divide segments and mux
+        const auto seg1 = LMX2592_CHDIV_SEGS[output_divider_index][0];
+        const auto seg2 = LMX2592_CHDIV_SEGS[output_divider_index][1];
+        const auto seg3 = LMX2592_CHDIV_SEGS[output_divider_index][2];
+
+        _regs.chdiv_seg_sel = lmx2592_regs_t::chdiv_seg_sel_t::CHDIV_SEG_SEL_POWERDOWN;
+
+        if (seg1 > 1) {
+            _regs.chdiv_seg_sel = lmx2592_regs_t::chdiv_seg_sel_t::CHDIV_SEG_SEL_DIV_SEG_1;
+            _regs.chdiv_seg1_en = 1;
+            _regs.outa_mux = lmx2592_regs_t::outa_mux_t::OUTA_MUX_DIVIDER;
+            _regs.outb_mux = lmx2592_regs_t::outb_mux_t::OUTB_MUX_DIVIDER;
+            _regs.vco_dista_pd = 1;
+            _regs.vco_distb_pd = 1;
+            _regs.chdiv_dist_pd = 0;
+
+            if (_regs.outa_pd == 0) {
+                _regs.chdiv_dista_en = 1;
+            }
+            if (_regs.outb_pd == 0) {
+                _regs.chdiv_distb_en = 1;
+            }
+
+        } else {
+            _regs.chdiv_seg1_en = 0;
+            _regs.outa_mux = lmx2592_regs_t::outa_mux_t::OUTA_MUX_VCO;
+            _regs.outb_mux = lmx2592_regs_t::outb_mux_t::OUTB_MUX_VCO;
+            _regs.chdiv_dist_pd = 1;
+
+            if (_regs.outa_pd == 0) {
+                _regs.vco_dista_pd = 0;
+            }
+            if (_regs.outb_pd == 0) {
+                _regs.vco_distb_pd = 0;
+            }
+        }
+
+        if (seg1 == 2) {
+            _regs.chdiv_seg1 = lmx2592_regs_t::chdiv_seg1_t::CHDIV_SEG1_DIVIDE_BY_2;
+        } else if (seg1 == 3) {
+            _regs.chdiv_seg1 = lmx2592_regs_t::chdiv_seg1_t::CHDIV_SEG1_DIVIDE_BY_3;
+        }
+
+        if (seg2 > 1) {
+            _regs.chdiv_seg2_en = 1;
+            _regs.chdiv_seg_sel = lmx2592_regs_t::chdiv_seg_sel_t::CHDIV_SEG_SEL_DIV_SEG_1_AND_2;
+        } else {
+            _regs.chdiv_seg2_en = 0;
+        }
+
+        if (seg2 == 1) {
+            _regs.chdiv_seg2 = lmx2592_regs_t::chdiv_seg2_t::CHDIV_SEG2_POWERDOWN;
+        } else if (seg2 == 2) {
+            _regs.chdiv_seg2 = lmx2592_regs_t::chdiv_seg2_t::CHDIV_SEG2_DIVIDE_BY_2;
+        } else if (seg2 == 4) {
+            _regs.chdiv_seg2 = lmx2592_regs_t::chdiv_seg2_t::CHDIV_SEG2_DIVIDE_BY_4;
+        } else if (seg2 == 6) {
+            _regs.chdiv_seg2 = lmx2592_regs_t::chdiv_seg2_t::CHDIV_SEG2_DIVIDE_BY_6;
+        } else if (seg2 == 8) {
+            _regs.chdiv_seg2 = lmx2592_regs_t::chdiv_seg2_t::CHDIV_SEG2_DIVIDE_BY_8;
+        }
+
+        if (seg3 > 1) {
+            _regs.chdiv_seg3_en = 1;
+            _regs.chdiv_seg_sel = lmx2592_regs_t::chdiv_seg_sel_t::CHDIV_SEG_SEL_DIV_SEG_1_2_AND_3;
+        } else {
+            _regs.chdiv_seg3_en = 0;
+        }
+
+        if (seg3 == 1) {
+            _regs.chdiv_seg3 = lmx2592_regs_t::chdiv_seg3_t::CHDIV_SEG3_POWERDOWN;
+        } else if (seg3 == 2) {
+            _regs.chdiv_seg3 = lmx2592_regs_t::chdiv_seg3_t::CHDIV_SEG3_DIVIDE_BY_2;
+        } else if (seg3 == 4) {
+            _regs.chdiv_seg3 = lmx2592_regs_t::chdiv_seg3_t::CHDIV_SEG3_DIVIDE_BY_4;
+        } else if (seg3 == 6) {
+            _regs.chdiv_seg3 = lmx2592_regs_t::chdiv_seg3_t::CHDIV_SEG3_DIVIDE_BY_6;
+        } else if (seg3 == 8) {
+            _regs.chdiv_seg3 = lmx2592_regs_t::chdiv_seg3_t::CHDIV_SEG3_DIVIDE_BY_8;
+        }
+    }
+};
+
+lmx2592_impl::sptr lmx2592_iface::make(write_spi_t write, read_spi_t read) {
+    return std::make_shared<lmx2592_impl>(write, read);
+}