1 files changed, 77 insertions, 0 deletions
diff --git a/host/lib/rfnoc/fir_block_ctrl_impl.cpp b/host/lib/rfnoc/fir_block_ctrl_impl.cpp
new file mode 100644
index 000000000..4267e0b22
--- /dev/null
+++ b/host/lib/rfnoc/fir_block_ctrl_impl.cpp
@@ -0,0 +1,77 @@
+//
+// Copyright 2014-2018 Ettus Research, a National Instruments Company
+//
+// SPDX-License-Identifier: GPL-3.0-or-later
+//
+
+#include <uhd/rfnoc/fir_block_ctrl.hpp>
+#include <uhd/convert.hpp>
+#include <uhd/utils/log.hpp>
+
+using namespace uhd::rfnoc;
+
+class fir_block_ctrl_impl : public fir_block_ctrl
+{
+public:
+    static const uint32_t RB_NUM_TAPS     = 0;
+    static const uint32_t SR_RELOAD       = 128;
+    static const uint32_t SR_RELOAD_TLAST = 129;
+    static const uint32_t SR_CONFIG       = 130;
+
+    UHD_RFNOC_BLOCK_CONSTRUCTOR(fir_block_ctrl),
+        _item_type("sc16") // We only support sc16 in this block
+    {
+        _n_taps = uint32_t(user_reg_read64(RB_NUM_TAPS));
+        UHD_LOGGER_DEBUG(unique_id())
+            << "fir_block::fir_block() n_taps ==" << _n_taps << std::endl;
+        UHD_ASSERT_THROW(_n_taps);
+
+        // Default to Dirac impulse
+        std::vector<int> default_taps(1, 20000);
+        set_taps(default_taps);
+    }
+
+    void set_taps(const std::vector<int> &taps_)
+    {
+        UHD_LOGGER_TRACE(unique_id()) << "fir_block::set_taps()" << std::endl;
+        if (taps_.size() > _n_taps) {
+            throw uhd::value_error(str(
+                boost::format("FIR block: Too many filter coefficients! Provided %d, FIR allows %d.\n")
+                % taps_.size() % _n_taps
+            ));
+        }
+        for (size_t i = 0; i < taps_.size(); i++) {
+            if (taps_[i] > 32767 || taps_[i] < -32768) {
+                throw uhd::value_error(str(
+                    boost::format("FIR block: Coefficient %d out of range! Value %d, Allowed range [-32768,32767].\n")
+                    % i % taps_[i]));
+            }
+        }
+        std::vector<int> taps = taps_;
+        if (taps.size() < _n_taps) {
+            taps.resize(_n_taps, 0);
+        }
+
+        // Write taps via the reload bus
+        for (size_t i = 0; i < taps.size() - 1; i++) {
+            sr_write(SR_RELOAD, uint32_t(taps[i]));
+        }
+        // Assert tlast when sending the spinal tap (haha, it's actually the final tap).
+        sr_write(SR_RELOAD_TLAST, uint32_t(taps.back()));
+        // Send the configuration word to replace the existing coefficients with the new ones.
+        // Note: This configuration bus does not require tlast
+        sr_write(SR_CONFIG, 0);
+    }
+
+    //! Returns the number of filter taps in this block.
+    size_t get_n_taps() const
+    {
+        return _n_taps;
+    }
+
+private:
+    const std::string _item_type;
+    size_t _n_taps;
+};
+
+UHD_RFNOC_BLOCK_REGISTER(fir_block_ctrl, "FIR");