From 7591060fbd24bde23552be77fb269b298efa3a24 Mon Sep 17 00:00:00 2001
From: tangxifan <tangxifan@gmail.com>
Date: Wed, 23 Sep 2020 21:45:06 -0600
Subject: [PATCH] [Architecture] Add configurable latch Verilog designs and
 assoicated architectures

---
 .../VerilogNetlists/config_latch_set.v        | 37 +++++++++++++++++
 .../VerilogNetlists/config_latch_set_reset.v  | 41 +++++++++++++++++++
 .../k4_N4_40nm_frame_use_set_openfpga.xml     |  6 +--
 3 files changed, 81 insertions(+), 3 deletions(-)
 create mode 100644 openfpga_flow/VerilogNetlists/config_latch_set.v
 create mode 100644 openfpga_flow/VerilogNetlists/config_latch_set_reset.v

diff --git a/openfpga_flow/VerilogNetlists/config_latch_set.v b/openfpga_flow/VerilogNetlists/config_latch_set.v
new file mode 100644
index 000000000..945df2377
--- /dev/null
+++ b/openfpga_flow/VerilogNetlists/config_latch_set.v
@@ -0,0 +1,37 @@
+//-----------------------------------------------------
+// Design Name : config_latch
+// File Name   : config_latch.v
+// Function    : A Configurable Latch where data storage
+//               can be updated when wl is enabled
+//               Set is active high
+// Coder       : Xifan TANG
+//-----------------------------------------------------
+module config_latch_set (
+  input set, // Reset input
+  input wl, // Data Enable
+  input bl, // Data Input
+  output Q, // Q output
+  output Qb // Q output
+);
+//------------Internal Variables--------
+reg q_reg;
+
+//-------------Code Starts Here---------
+always @ (set or bl or wl) begin
+  if (set) begin
+    q_reg <= 1'b1;
+  end else if (1'b1 == wl) begin
+    q_reg <= bl;
+  end
+end
+
+`ifndef ENABLE_FORMAL_VERIFICATION
+// Wire q_reg to Q
+assign Q = q_reg;
+assign Qb = ~q_reg;
+`else
+assign Q = 1'bZ;
+assign Qb = !Q;
+`endif
+
+endmodule
diff --git a/openfpga_flow/VerilogNetlists/config_latch_set_reset.v b/openfpga_flow/VerilogNetlists/config_latch_set_reset.v
new file mode 100644
index 000000000..ad9f75322
--- /dev/null
+++ b/openfpga_flow/VerilogNetlists/config_latch_set_reset.v
@@ -0,0 +1,41 @@
+//-----------------------------------------------------
+// Design Name : config_latch
+// File Name   : config_latch.v
+// Function    : A Configurable Latch where data storage
+//               can be updated when wl is enabled
+//               Reset is active high
+//               Set is active high
+// Coder       : Xifan TANG
+//-----------------------------------------------------
+module config_latch_set_reset (
+  input reset, // Reset input
+  input set, // Set input
+  input wl, // Data Enable
+  input bl, // Data Input
+  output Q, // Q output
+  output Qb // Q output
+);
+//------------Internal Variables--------
+reg q_reg;
+
+//-------------Code Starts Here---------
+always @ (reset or set or bl or wl) begin
+  if (reset) begin
+    q_reg <= 1'b0;
+  end else if (set) begin
+    q_reg <= 1'b1;
+  end else if (1'b1 == wl) begin
+    q_reg <= bl;
+  end
+end
+
+`ifndef ENABLE_FORMAL_VERIFICATION
+// Wire q_reg to Q
+assign Q = q_reg;
+assign Qb = ~q_reg;
+`else
+assign Q = 1'bZ;
+assign Qb = !Q;
+`endif
+
+endmodule
diff --git a/openfpga_flow/openfpga_arch/k4_N4_40nm_frame_use_set_openfpga.xml b/openfpga_flow/openfpga_arch/k4_N4_40nm_frame_use_set_openfpga.xml
index a3ea99857..2785712a8 100644
--- a/openfpga_flow/openfpga_arch/k4_N4_40nm_frame_use_set_openfpga.xml
+++ b/openfpga_flow/openfpga_arch/k4_N4_40nm_frame_use_set_openfpga.xml
@@ -146,7 +146,7 @@
       <port type="sram" prefix="sram" size="16"/>
     </circuit_model>
     <!--Scan-chain DFF subckt ports should be defined as <D> <Q> <Qb> <CLK> <RESET> <SET>  -->
-    <circuit_model type="sram" name="config_latch" prefix="config_latch" spice_netlist="${OPENFPGA_PATH}/openfpga_flow/SpiceNetlists/config_latch.sp" verilog_netlist="${OPENFPGA_PATH}/openfpga_flow/VerilogNetlists/config_latch.v">
+    <circuit_model type="sram" name="config_latch_set_set" prefix="config_latch_set_set" spice_netlist="${OPENFPGA_PATH}/openfpga_flow/SpiceNetlists/config_latch_set_set.sp" verilog_netlist="${OPENFPGA_PATH}/openfpga_flow/VerilogNetlists/config_latch_set_set.v">
        <design_technology type="cmos"/>
        <input_buffer exist="true" circuit_model_name="INVTX1"/>
        <output_buffer exist="true" circuit_model_name="INVTX1"/>
@@ -161,13 +161,13 @@
       <input_buffer exist="true" circuit_model_name="INVTX1"/>
       <output_buffer exist="true" circuit_model_name="INVTX1"/>
       <port type="inout" prefix="pad" size="1" is_global="true" is_io="true"/>
-      <port type="sram" prefix="en" size="1" mode_select="true" circuit_model_name="config_latch" default_val="1"/>
+      <port type="sram" prefix="en" size="1" mode_select="true" circuit_model_name="config_latch_set" default_val="1"/>
       <port type="input" prefix="outpad" size="1"/>
       <port type="output" prefix="inpad" size="1"/>
     </circuit_model>
   </circuit_library>
   <configuration_protocol>
-    <organization type="frame_based" circuit_model_name="config_latch"/>
+    <organization type="frame_based" circuit_model_name="config_latch_set"/>
   </configuration_protocol>
   <connection_block>
     <switch name="ipin_cblock" circuit_model_name="mux_2level_tapbuf"/>