usrp: added clipping to link max rate when setting sample rate

4 files changed, 22 insertions, 4 deletions

diff --git a/host/lib/usrp/cores/rx_dsp_core_200.cpp b/host/lib/usrp/cores/rx_dsp_core_200.cpp
index 0c065e228..e059ddfca 100644
--- a/host/lib/usrp/cores/rx_dsp_core_200.cpp
+++ b/host/lib/usrp/cores/rx_dsp_core_200.cpp
@@ -18,6 +18,7 @@
 #include "rx_dsp_core_200.hpp"
 #include <uhd/types/dict.hpp>
 #include <uhd/exception.hpp>
+#include <uhd/utils/algorithm.hpp>
 #include <boost/assign/list_of.hpp>
 #include <boost/math/special_functions/round.hpp>
 #include <boost/math/special_functions/sign.hpp>
@@ -122,8 +123,14 @@ public:
         _tick_rate = rate;
     }
 
+    void set_link_rate(const double rate){
+        _link_rate = rate/sizeof(boost::uint32_t); //in samps/s
+    }
+
     double set_host_rate(const double rate){
-        const size_t decim_rate = boost::math::iround(_tick_rate/rate);
+        const size_t decim_rate = uhd::clip<size_t>(
+            boost::math::iround(_tick_rate/rate), size_t(std::ceil(_tick_rate/_link_rate)), 512
+        );
         size_t decim = decim_rate;
 
         //determine which half-band filters are activated
@@ -172,7 +179,7 @@ public:
 private:
     wb_iface::sptr _iface;
     const size_t _dsp_base, _ctrl_base;
-    double _tick_rate;
+    double _tick_rate, _link_rate;
     bool _continuous_streaming;
 };
 
diff --git a/host/lib/usrp/cores/rx_dsp_core_200.hpp b/host/lib/usrp/cores/rx_dsp_core_200.hpp
index 72ed07230..abe7bf817 100644
--- a/host/lib/usrp/cores/rx_dsp_core_200.hpp
+++ b/host/lib/usrp/cores/rx_dsp_core_200.hpp
@@ -44,6 +44,8 @@ public:
 
     virtual void set_tick_rate(const double rate) = 0;
 
+    virtual void set_link_rate(const double rate) = 0;
+
     virtual double set_host_rate(const double rate) = 0;
 
     virtual uhd::meta_range_t get_freq_range(void) = 0;
diff --git a/host/lib/usrp/cores/tx_dsp_core_200.cpp b/host/lib/usrp/cores/tx_dsp_core_200.cpp
index d2981bbdb..222ba589a 100644
--- a/host/lib/usrp/cores/tx_dsp_core_200.cpp
+++ b/host/lib/usrp/cores/tx_dsp_core_200.cpp
@@ -18,6 +18,7 @@
 #include "tx_dsp_core_200.hpp"
 #include <uhd/types/dict.hpp>
 #include <uhd/exception.hpp>
+#include <uhd/utils/algorithm.hpp>
 #include <boost/assign/list_of.hpp>
 #include <boost/math/special_functions/round.hpp>
 #include <boost/math/special_functions/sign.hpp>
@@ -68,8 +69,14 @@ public:
         _tick_rate = rate;
     }
 
+    void set_link_rate(const double rate){
+        _link_rate = rate/sizeof(boost::uint32_t); //in samps/s
+    }
+
     double set_host_rate(const double rate){
-        const size_t interp_rate = boost::math::iround(_tick_rate/rate);
+        const size_t interp_rate = uhd::clip<size_t>(
+            boost::math::iround(_tick_rate/rate), size_t(std::ceil(_tick_rate/_link_rate)), 512
+        );
         size_t interp = interp_rate;
 
         //determine which half-band filters are activated
@@ -125,7 +132,7 @@ public:
 private:
     wb_iface::sptr _iface;
     const size_t _dsp_base, _ctrl_base;
-    double _tick_rate;
+    double _tick_rate, _link_rate;
 };
 
 tx_dsp_core_200::sptr tx_dsp_core_200::make(wb_iface::sptr iface, const size_t dsp_base, const size_t ctrl_base, const boost::uint32_t sid){
diff --git a/host/lib/usrp/cores/tx_dsp_core_200.hpp b/host/lib/usrp/cores/tx_dsp_core_200.hpp
index f74ec0bdb..65f822558 100644
--- a/host/lib/usrp/cores/tx_dsp_core_200.hpp
+++ b/host/lib/usrp/cores/tx_dsp_core_200.hpp
@@ -36,6 +36,8 @@ public:
 
     virtual void set_tick_rate(const double rate) = 0;
 
+    virtual void set_link_rate(const double rate) = 0;
+
     virtual double set_host_rate(const double rate) = 0;
 
     virtual uhd::meta_range_t get_freq_range(void) = 0;