diff --git a/sdc-plugin/buffers.cc b/sdc-plugin/buffers.cc
index 709c7f9..c997bfa 100644
--- a/sdc-plugin/buffers.cc
+++ b/sdc-plugin/buffers.cc
@@ -25,12 +25,12 @@
 const float Pll::delay = 0;
 const std::string Pll::name = "PLLE2_ADV";
 
-Pll::Pll(RTLIL::Cell* cell, float input_clock_period, float input_clock_shift) {
+Pll::Pll(RTLIL::Cell* cell, float input_clock_period, float input_clock_rising_edge) {
     assert(RTLIL::unescape_id(cell->type) == "PLLE2_ADV");
     FetchParams(cell);
     CheckInputClockPeriod(cell, input_clock_period);
     CalculateOutputClockPeriods();
-    CalculateOutputClockWaveforms(input_clock_shift);
+    CalculateOutputClockWaveforms(input_clock_rising_edge);
 }
 
 void Pll::CheckInputClockPeriod(RTLIL::Cell* cell, float input_clock_period) {
@@ -70,10 +70,10 @@
     }
 }
 
-void Pll::CalculateOutputClockWaveforms(float input_clock_shift) {
+void Pll::CalculateOutputClockWaveforms(float input_clock_rising_edge) {
     for (auto output : outputs) {
 	float output_clock_period = clkout_period.at(output);
-	clkout_rising_edge[output] = fmod(input_clock_shift - (clk_fbout_phase / 360.0) * ClkinPeriod() + output_clock_period * (clkout_phase[output] / 360.0), output_clock_period);
+	clkout_rising_edge[output] = fmod(input_clock_rising_edge - (clk_fbout_phase / 360.0) * ClkinPeriod() + output_clock_period * (clkout_phase[output] / 360.0), output_clock_period);
 	clkout_falling_edge[output] = fmod(clkout_rising_edge[output] + clkout_duty_cycle[output] * output_clock_period, output_clock_period);
     }
 }
diff --git a/sdc-plugin/buffers.h b/sdc-plugin/buffers.h
index d89f792..72beb0b 100644
--- a/sdc-plugin/buffers.h
+++ b/sdc-plugin/buffers.h
@@ -42,7 +42,7 @@
 };
 
 struct Pll {
-    Pll(RTLIL::Cell* cell, float input_clock_period, float input_clock_shift);
+    Pll(RTLIL::Cell* cell, float input_clock_period, float input_clock_rising_edge);
 
     // Helper function to fetch a cell parameter or return a default value
     static float FetchParam(RTLIL::Cell* cell, std::string&& param_name,
@@ -72,7 +72,7 @@
     void CalculateOutputClockPeriods();
 
     // Calculate the rising and falling edges of the output clocks
-    void CalculateOutputClockWaveforms(float input_clock_shift);
+    void CalculateOutputClockWaveforms(float input_clock_rising_edge);
 
     static const float delay;
     static const std::string name;