diff --git a/openfpga/src/annotation/append_clock_rr_graph.cpp b/openfpga/src/annotation/append_clock_rr_graph.cpp
index 5b5b5f561..10f9fd227 100644
--- a/openfpga/src/annotation/append_clock_rr_graph.cpp
+++ b/openfpga/src/annotation/append_clock_rr_graph.cpp
@@ -2,6 +2,7 @@
 #include "vtr_assert.h"
 #include "vtr_geometry.h"
 #include "vtr_log.h"
+#include "command_exit_codes.h"
 
 /* begin namespace openfpga */
 namespace openfpga {
@@ -11,11 +12,50 @@ namespace openfpga {
  * This is used by bitstream generator mainly as a fast look-up to
  * get mapped blocks with a given coordinate
  *******************************************************************/
-int append_clock_rr_graph(DeviceContext& device_ctx,
-                          const ClockNetwork& clk_ntwk) {
-  VTR_LOG("Adding clock nodes to routing resource graph...");
+int append_clock_rr_graph(DeviceContext& vpr_device_ctx,
+                          const ClockNetwork& clk_ntwk,
+                          const bool& verbose) {
+  vtr::ScopedStartFinishTimer timer("Adding clock nodes to routing resource graph");
 
-  VTR_LOG("Done\n");
+  /* Skip if there is no clock tree */
+  if (clk_ntwk.num_trees()) {
+    VTR_LOG("Skip due to 0 clock trees.\nDouble check your clock architecture definition if this is unexpected\n");
+    return CMD_EXEC_SUCCESS;
+  }
+
+  /* Walk through the GSB array and add clock nodes to each GSB.
+   * Note that the GSB array is smaller than the grids by 1 column and 1 row!!!
+   */
+  vtr::Point<size_t> gsb_range(vpr_device_ctx.grid.width() - 1,
+                               vpr_device_ctx.grid.height() - 1);
+
+  size_t gsb_cnt = 0;
+  /* For each switch block, determine the size of array */
+  for (size_t ix = 0; ix < gsb_range.x(); ++ix) {
+    for (size_t iy = 0; iy < gsb_range.y(); ++iy) {
+      /* Here we give the builder the fringe coordinates so that it can handle
+       * the GSBs at the borderside correctly sort drive_rr_nodes should be
+       * called if required by users
+       */
+      const RRGSB& rr_gsb =
+        build_rr_gsb(vpr_device_ctx,
+                     vtr::Point<size_t>(vpr_device_ctx.grid.width() - 2,
+                                        vpr_device_ctx.grid.height() - 2),
+                     vtr::Point<size_t>(ix, iy));
+
+      /* Add clock nodes to device_rr_gsb */
+      vtr::Point<size_t> gsb_coordinate = rr_gsb.get_sb_coordinate();
+      gsb_cnt++; /* Update counter */
+      /* Print info */
+      VTR_LOGV(verbose, "[%lu%] Added clock nodes to GSB[%lu][%lu]\r",
+              100 * gsb_cnt / (gsb_range.x() * gsb_range.y()), ix, iy);
+    }
+  }
+  /* Report number of added clock nodes and edges */
+  VTR_LOGV(verbose, "Appended clock nodes to %d General Switch Blocks (GSBs).\n",
+           gsb_range.x() * gsb_range.y());
+
+  return CMD_EXEC_SUCCESS;
 }
 
 } /* end namespace openfpga */
diff --git a/openfpga/src/annotation/append_clock_rr_graph.h b/openfpga/src/annotation/append_clock_rr_graph.h
index d3658c9e1..9c20c51a6 100644
--- a/openfpga/src/annotation/append_clock_rr_graph.h
+++ b/openfpga/src/annotation/append_clock_rr_graph.h
@@ -14,8 +14,9 @@
 /* begin namespace openfpga */
 namespace openfpga {
 
-int append_clock_rr_graph(DeviceContext& device_ctx,
-                          const ClockNetwork& clk_ntwk);
+int append_clock_rr_graph(DeviceContext& vpr_device_ctx,
+                          const ClockNetwork& clk_ntwk,
+                          const bool& verbose);
 
 } /* end namespace openfpga */
 
diff --git a/openfpga/src/base/openfpga_link_arch_template.h b/openfpga/src/base/openfpga_link_arch_template.h
index ae601ae0b..99651b5a7 100644
--- a/openfpga/src/base/openfpga_link_arch_template.h
+++ b/openfpga/src/base/openfpga_link_arch_template.h
@@ -197,7 +197,7 @@ int append_clock_rr_graph_template(T& openfpga_ctx, const Command& cmd,
 
   CommandOptionId opt_verbose = cmd.option("verbose");
 
-  return append_clock_rr_graph(g_vpr_ctx.mutable_device(), openfpga_ctx.clock_arch());
+  return append_clock_rr_graph(g_vpr_ctx.mutable_device(), openfpga_ctx.clock_arch(), cmd_context.option_enable(cmd, opt_verbose));
 }