diff --git a/mistral/arch.cc b/mistral/arch.cc
index 516d1de8..cfa3e8b3 100644
--- a/mistral/arch.cc
+++ b/mistral/arch.cc
@@ -248,6 +248,8 @@ bool Arch::isValidBelForCellType(IdString cell_type, BelId bel) const
         return is_comb_cell(cell_type);
     else if (bel_type == id_MISTRAL_IO)
         return is_io_cell(cell_type);
+    else if (bel_type == id_MISTRAL_CLKENA)
+        return is_clkbuf_cell(cell_type);
     else
         return bel_type == cell_type;
 }
@@ -258,6 +260,8 @@ BelBucketId Arch::getBelBucketForCellType(IdString cell_type) const
         return id_MISTRAL_COMB;
     else if (is_io_cell(cell_type))
         return id_MISTRAL_IO;
+    else if (is_clkbuf_cell(cell_type))
+        return id_MISTRAL_CLKENA;
     else
         return cell_type;
 }
diff --git a/mistral/arch.h b/mistral/arch.h
index c7d369f1..5913a615 100644
--- a/mistral/arch.h
+++ b/mistral/arch.h
@@ -480,6 +480,10 @@ struct Arch : BaseArch<ArchRanges>
 
     // -------------------------------------------------
 
+    bool is_clkbuf_cell(IdString cell_type) const; // globals.cc
+
+    // -------------------------------------------------
+
     static const std::string defaultPlacer;
     static const std::vector<std::string> availablePlacers;
     static const std::string defaultRouter;
diff --git a/mistral/bitstream.cc b/mistral/bitstream.cc
index e31b94af..92d86410 100644
--- a/mistral/bitstream.cc
+++ b/mistral/bitstream.cc
@@ -201,7 +201,7 @@ struct MistralBitgen
             int bi = ctx->bel_data(ci->bel).block_index;
             if (ctx->is_io_cell(ci->type))
                 write_io_cell(ci, loc.x, loc.y, bi);
-            else if (ci->type == id_MISTRAL_CLKENA)
+            else if (ctx->is_clkbuf_cell(ci->type))
                 write_clkbuf_cell(ci, loc.x, loc.y, bi);
         }
     }
diff --git a/mistral/constids.inc b/mistral/constids.inc
index 4f7d3ecf..6bb45c3c 100644
--- a/mistral/constids.inc
+++ b/mistral/constids.inc
@@ -75,3 +75,4 @@ X(Y)
 X(LOC)
 
 X(MISTRAL_CLKENA)
+X(MISTRAL_CLKBUF)
diff --git a/mistral/globals.cc b/mistral/globals.cc
index 9cbabbca..3203893b 100644
--- a/mistral/globals.cc
+++ b/mistral/globals.cc
@@ -38,4 +38,9 @@ void Arch::create_clkbuf(int x, int y)
     }
 }
 
+bool Arch::is_clkbuf_cell(IdString cell_type) const
+{
+    return cell_type == id_MISTRAL_CLKENA || cell_type == id_MISTRAL_CLKBUF;
+}
+
 NEXTPNR_NAMESPACE_END