Added verilog file for the "fake diode" cell used by openlane in sky130_fd_sc_hd.
diff --git a/sky130/Makefile.in b/sky130/Makefile.in
index 321a98d..d8fe84b 100644
--- a/sky130/Makefile.in
+++ b/sky130/Makefile.in
@@ -499,6 +499,7 @@
${STAGE} -source ./custom -target ${STAGING_PATH}/${SKY130A} \
-gds %l/gds/*.gds \
-lef %l/lef/*.lef \
+ -verilog %l/verilog/*.v \
-library digital sky130_fd_sc_hd |& tee -a ${SKY130A}_install.log
# Add a maskhint set for the GPIO pad .mag view to prevent problems writing
# when writing HVI to GDS during hierarchical adjustments.
diff --git a/sky130/custom/sky130_fd_sc_hd/verilog/sky130_ef_sc_hd__diode_2.v b/sky130/custom/sky130_fd_sc_hd/verilog/sky130_ef_sc_hd__diode_2.v
new file mode 100644
index 0000000..4ddd77a
--- /dev/null
+++ b/sky130/custom/sky130_fd_sc_hd/verilog/sky130_ef_sc_hd__diode_2.v
@@ -0,0 +1,97 @@
+/**
+ * Copyright 2020 The SkyWater PDK Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+`ifndef SKY130_EF_SC_HD__FAKEDIODE_2_V
+`define SKY130_EF_SC_HD__FAKEDIODE_2_V
+
+/**
+ * fakediode: Antenna tie-down diode with no connection between the DIODE
+ * pin and the diode. This is just the sky130_fd_sc_hd__diode_2 cell with
+ * the contacts removed between the diode and the pin. It is used by the
+ * openlane synthesis flow to preemptively put antenna tie-downs close to
+ * every pin without making a connection. If the net needs an antenna
+ * tiedown, the fakediode cell can be replaced by the real diode cell.
+ *
+ * Verilog wrapper for diode with size of 2 units. Note that the wrapper
+ * is around the original SkyWater diode base cell; because the diode
+ * has no function in verilog, there is no difference between the verilog
+ * definitions of the diode and fake diode other than the cell name.
+ *
+ */
+
+`timescale 1ns / 1ps
+`default_nettype none
+
+
+`ifdef USE_POWER_PINS
+/*********************************************************/
+
+`celldefine
+module sky130_ef_sc_hd__fakediode_2 (
+ DIODE,
+ VPWR ,
+ VGND ,
+ VPB ,
+ VNB
+);
+
+ input DIODE;
+ input VPWR ;
+ input VGND ;
+ input VPB ;
+ input VNB ;
+ sky130_fd_sc_hd__diode base (
+ .DIODE(DIODE),
+ .VPWR(VPWR),
+ .VGND(VGND),
+ .VPB(VPB),
+ .VNB(VNB)
+ );
+
+endmodule
+`endcelldefine
+
+/*********************************************************/
+`else // If not USE_POWER_PINS
+/*********************************************************/
+
+`celldefine
+module sky130_ef_sc_hd__fakediode_2 (
+ DIODE
+);
+
+ input DIODE;
+
+ // Voltage supply signals
+ supply1 VPWR;
+ supply0 VGND;
+ supply1 VPB ;
+ supply0 VNB ;
+
+ sky130_fd_sc_hd__diode base (
+ .DIODE(DIODE)
+ );
+
+endmodule
+`endcelldefine
+
+/*********************************************************/
+`endif // USE_POWER_PINS
+
+`default_nettype wire
+`endif // SKY130_EF_SC_HD__FAKEDIODE_2_V
