From 910f8471dd88471e44596afb6598711aff18bc62 Mon Sep 17 00:00:00 2001
From: tangxifan <tangxifan@gmail.com>
Date: Wed, 17 Mar 2021 15:10:05 -0600
Subject: [PATCH] [Arch] Add a representative heterogeneous FPGA architecture
 with single-mode BRAM (which can be synthesized by Yosys)

---
 ..._N10_adder_chain_dpram8K_40nm_openfpga.xml | 273 +++++++
 ..._N10_tileable_adder_chain_dpram8K_40nm.xml | 748 ++++++++++++++++++
 2 files changed, 1021 insertions(+)
 create mode 100644 openfpga_flow/openfpga_arch/k6_frac_N10_adder_chain_dpram8K_40nm_openfpga.xml
 create mode 100644 openfpga_flow/vpr_arch/k6_frac_N10_tileable_adder_chain_dpram8K_40nm.xml

diff --git a/openfpga_flow/openfpga_arch/k6_frac_N10_adder_chain_dpram8K_40nm_openfpga.xml b/openfpga_flow/openfpga_arch/k6_frac_N10_adder_chain_dpram8K_40nm_openfpga.xml
new file mode 100644
index 000000000..37beb67bf
--- /dev/null
+++ b/openfpga_flow/openfpga_arch/k6_frac_N10_adder_chain_dpram8K_40nm_openfpga.xml
@@ -0,0 +1,273 @@
+<!-- Architecture annotation for OpenFPGA framework
+     This annotation supports the k6_N10_40nm.xml 
+     - General purpose logic block
+       - K = 6, N = 10, I = 40
+       - Single mode
+     - Routing architecture
+       - L = 4, fc_in = 0.15, fc_out = 0.1
+  -->
+<openfpga_architecture>
+  <technology_library>
+    <device_library>
+      <device_model name="logic" type="transistor">
+        <lib type="industry" corner="TOP_TT" ref="M" path="${OPENFPGA_PATH}/openfpga_flow/tech/PTM_45nm/45nm.pm"/>
+        <design vdd="0.9" pn_ratio="2"/>
+        <pmos name="pch" chan_length="40e-9" min_width="140e-9" variation="logic_transistor_var"/>
+        <nmos name="nch" chan_length="40e-9" min_width="140e-9" variation="logic_transistor_var"/>
+      </device_model>
+      <device_model name="io" type="transistor">
+        <lib type="academia" ref="M" path="${OPENFPGA_PATH}/openfpga_flow/tech/PTM_45nm/45nm.pm"/>
+        <design vdd="2.5" pn_ratio="3"/>
+        <pmos name="pch_25" chan_length="270e-9" min_width="320e-9" variation="io_transistor_var"/>
+        <nmos name="nch_25" chan_length="270e-9" min_width="320e-9" variation="io_transistor_var"/>
+      </device_model>
+    </device_library>
+    <variation_library>
+      <variation name="logic_transistor_var" abs_deviation="0.1" num_sigma="3"/>
+      <variation name="io_transistor_var" abs_deviation="0.1" num_sigma="3"/>
+    </variation_library>
+  </technology_library>
+  <circuit_library>
+    <circuit_model type="inv_buf" name="INVTX1" prefix="INVTX1" is_default="true">
+      <design_technology type="cmos" topology="inverter" size="1"/>
+      <device_technology device_model_name="logic"/>
+      <port type="input" prefix="in" size="1"/>
+      <port type="output" prefix="out" size="1"/>
+      <delay_matrix type="rise" in_port="in" out_port="out">
+        10e-12
+      </delay_matrix>
+      <delay_matrix type="fall" in_port="in" out_port="out">
+        10e-12
+      </delay_matrix>
+    </circuit_model>
+    <circuit_model type="inv_buf" name="buf4" prefix="buf4" is_default="false">
+      <design_technology type="cmos" topology="buffer" size="1" num_level="2" f_per_stage="4"/>
+      <device_technology device_model_name="logic"/>
+      <port type="input" prefix="in" size="1"/>
+      <port type="output" prefix="out" size="1"/>
+      <delay_matrix type="rise" in_port="in" out_port="out">
+        10e-12
+      </delay_matrix>
+      <delay_matrix type="fall" in_port="in" out_port="out">
+        10e-12
+      </delay_matrix>
+    </circuit_model>
+    <circuit_model type="inv_buf" name="tap_buf4" prefix="tap_buf4" is_default="false">
+      <design_technology type="cmos" topology="buffer" size="1" num_level="3" f_per_stage="4"/>
+      <device_technology device_model_name="logic"/>
+      <port type="input" prefix="in" size="1"/>
+      <port type="output" prefix="out" size="1"/>
+      <delay_matrix type="rise" in_port="in" out_port="out">
+        10e-12
+      </delay_matrix>
+      <delay_matrix type="fall" in_port="in" out_port="out">
+        10e-12
+      </delay_matrix>
+    </circuit_model>
+    <circuit_model type="gate" name="OR2" prefix="OR2" is_default="true">
+      <design_technology type="cmos" topology="OR"/>
+      <device_technology device_model_name="logic"/>
+      <input_buffer exist="false"/>
+      <output_buffer exist="false"/>
+      <port type="input" prefix="a" size="1"/>
+      <port type="input" prefix="b" size="1"/>
+      <port type="output" prefix="out" size="1"/>
+      <delay_matrix type="rise" in_port="a b" out_port="out">
+        10e-12 5e-12
+      </delay_matrix>
+      <delay_matrix type="fall" in_port="a b" out_port="out">
+        10e-12 5e-12
+      </delay_matrix>
+    </circuit_model>
+    <circuit_model type="pass_gate" name="TGATE" prefix="TGATE" is_default="true">
+      <design_technology type="cmos" topology="transmission_gate" nmos_size="1" pmos_size="2"/>
+      <device_technology device_model_name="logic"/>
+      <input_buffer exist="false"/>
+      <output_buffer exist="false"/>
+      <port type="input" prefix="in" size="1"/>
+      <port type="input" prefix="sel" size="1"/>
+      <port type="input" prefix="selb" size="1"/>
+      <port type="output" prefix="out" size="1"/>
+      <delay_matrix type="rise" in_port="in sel selb" out_port="out">
+        10e-12 5e-12 5e-12
+      </delay_matrix>
+      <delay_matrix type="fall" in_port="in sel selb" out_port="out">
+        10e-12 5e-12 5e-12
+      </delay_matrix>
+    </circuit_model>
+    <circuit_model type="chan_wire" name="chan_segment" prefix="track_seg" is_default="true">
+      <design_technology type="cmos"/>
+      <input_buffer exist="false"/>
+      <output_buffer exist="false"/>
+      <port type="input" prefix="in" size="1"/>
+      <port type="output" prefix="out" size="1"/>
+      <wire_param model_type="pi" R="101" C="22.5e-15" num_level="1"/> <!-- model_type could be T, res_val and cap_val DON'T CARE -->
+    </circuit_model>
+    <circuit_model type="wire" name="direct_interc" prefix="direct_interc" is_default="true">
+      <design_technology type="cmos"/>
+      <input_buffer exist="false"/>
+      <output_buffer exist="false"/>
+      <port type="input" prefix="in" size="1"/>
+      <port type="output" prefix="out" size="1"/>
+      <wire_param model_type="pi" R="0" C="0" num_level="1"/> <!-- model_type could be T, res_val cap_val should be defined -->
+    </circuit_model>
+    <circuit_model type="mux" name="mux_2level" prefix="mux_2level" dump_structural_verilog="true">
+      <design_technology type="cmos" structure="multi_level" num_level="2" add_const_input="true" const_input_val="1"/>
+      <input_buffer exist="true" circuit_model_name="INVTX1"/>
+      <output_buffer exist="true" circuit_model_name="INVTX1"/>
+      <pass_gate_logic circuit_model_name="TGATE"/>
+      <port type="input" prefix="in" size="1"/>
+      <port type="output" prefix="out" size="1"/>
+      <port type="sram" prefix="sram" size="1"/>
+    </circuit_model>
+    <circuit_model type="mux" name="mux_2level_tapbuf" prefix="mux_2level_tapbuf" dump_structural_verilog="true">
+      <design_technology type="cmos" structure="multi_level" num_level="2" add_const_input="true" const_input_val="1"/>
+      <input_buffer exist="true" circuit_model_name="INVTX1"/>
+      <output_buffer exist="true" circuit_model_name="tap_buf4"/>
+      <pass_gate_logic circuit_model_name="TGATE"/>
+      <port type="input" prefix="in" size="1"/>
+      <port type="output" prefix="out" size="1"/>
+      <port type="sram" prefix="sram" size="1"/>
+    </circuit_model>
+    <circuit_model type="mux" name="mux_1level_tapbuf" prefix="mux_1level_tapbuf" is_default="true" dump_structural_verilog="true">
+      <design_technology type="cmos" structure="one_level" add_const_input="true" const_input_val="1"/>
+      <input_buffer exist="true" circuit_model_name="INVTX1"/>
+      <output_buffer exist="true" circuit_model_name="tap_buf4"/>
+      <pass_gate_logic circuit_model_name="TGATE"/>
+      <port type="input" prefix="in" size="1"/>
+      <port type="output" prefix="out" size="1"/>
+      <port type="sram" prefix="sram" size="1"/>
+    </circuit_model>
+    <!--DFF subckt ports should be defined as <D> <Q> <CLK> <RESET> <SET>  -->
+    <circuit_model type="ff" name="DFFSRQ" prefix="DFFSRQ" spice_netlist="${OPENFPGA_PATH}/openfpga_flow/openfpga_cell_library/spice/dff.sp" verilog_netlist="${OPENFPGA_PATH}/openfpga_flow/openfpga_cell_library/verilog/dff.v">
+       <design_technology type="cmos"/>
+       <input_buffer exist="true" circuit_model_name="INVTX1"/>
+       <output_buffer exist="true" circuit_model_name="INVTX1"/>
+       <port type="input" prefix="D" size="1"/>
+       <port type="input" prefix="set" lib_name="SET" size="1" is_global="true" default_val="0" is_set="true"/>
+       <port type="input" prefix="reset" lib_name="RST" size="1" is_global="true" default_val="0" is_reset="true"/>
+       <port type="output" prefix="Q" size="1"/>
+       <port type="clock" prefix="clk" lib_name="CK" size="1" is_global="true" default_val="0" />
+    </circuit_model>
+    <circuit_model type="lut" name="frac_lut6" prefix="frac_lut6" dump_structural_verilog="true">
+      <design_technology type="cmos" fracturable_lut="true"/>
+      <input_buffer exist="true" circuit_model_name="INVTX1"/>
+      <output_buffer exist="true" circuit_model_name="INVTX1"/>
+      <lut_input_inverter exist="true" circuit_model_name="INVTX1"/>
+      <lut_input_buffer exist="true" circuit_model_name="buf4"/>
+      <lut_intermediate_buffer exist="true" circuit_model_name="buf4" location_map="-1-1-"/>
+      <pass_gate_logic circuit_model_name="TGATE"/>
+      <port type="input" prefix="in" size="6" tri_state_map="----11" circuit_model_name="OR2"/>
+      <port type="output" prefix="lut4_out" size="4" lut_frac_level="4" lut_output_mask="0,1,2,3"/>
+      <port type="output" prefix="lut5_out" size="2" lut_frac_level="5" lut_output_mask="0,1"/>
+      <port type="output" prefix="lut6_out" size="1" lut_output_mask="0"/>
+      <port type="sram" prefix="sram" size="64"/>
+      <port type="sram" prefix="mode" size="2" mode_select="true" circuit_model_name="DFFR" default_val="1"/>
+    </circuit_model>
+    <!--Scan-chain DFF subckt ports should be defined as <D> <Q> <Qb> <CLK> <RESET> <SET>  -->
+    <circuit_model type="ccff" name="DFFR" prefix="DFFR" spice_netlist="${OPENFPGA_PATH}/openfpga_flow/openfpga_cell_library/spice/dff.sp" verilog_netlist="${OPENFPGA_PATH}/openfpga_flow/openfpga_cell_library/verilog/dff.v">
+       <design_technology type="cmos"/>
+       <input_buffer exist="true" circuit_model_name="INVTX1"/>
+       <output_buffer exist="true" circuit_model_name="INVTX1"/>
+       <port type="input" prefix="pReset" lib_name="RST" size="1" is_global="true" default_val="0" is_reset="true" is_prog="true"/>
+       <port type="input" prefix="D" size="1"/>
+       <port type="output" prefix="Q" size="1"/>
+       <port type="output" prefix="QN" size="1"/>
+       <port type="clock" prefix="prog_clk" lib_name="CK" size="1" is_global="true" default_val="0" is_prog="true"/>
+    </circuit_model>
+    <circuit_model type="iopad" name="GPIO" prefix="GPIO" spice_netlist="${OPENFPGA_PATH}/openfpga_flow/openfpga_cell_library/spice/gpio.sp" verilog_netlist="${OPENFPGA_PATH}/openfpga_flow/openfpga_cell_library/verilog/gpio.v">
+      <design_technology type="cmos"/>
+      <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" is_data_io="true"/>
+      <port type="sram" prefix="DIR" size="1" mode_select="true" circuit_model_name="DFFR" default_val="1"/>
+      <port type="input" prefix="outpad" lib_name="A" size="1"/>
+      <port type="output" prefix="inpad" lib_name="Y" size="1"/>
+    </circuit_model>
+    <circuit_model type="hard_logic" name="ADDF" prefix="ADDF" is_default="true" spice_netlist="${OPENFPGA_PATH}/openfpga_flow/openfpga_cell_library/spice/adder.sp" verilog_netlist="${OPENFPGA_PATH}/openfpga_flow/openfpga_cell_library/verilog/adder.v">
+      <design_technology type="cmos"/>
+      <input_buffer exist="true" circuit_model_name="INVTX1"/>
+      <output_buffer exist="true" circuit_model_name="INVTX1"/>
+      <port type="input" prefix="a" lib_name="A" size="1"/>
+      <port type="input" prefix="b" lib_name="B" size="1"/>
+      <port type="input" prefix="cin" lib_name="CI" size="1"/>
+      <port type="output" prefix="sumout" lib_name="SUM" size="1"/>
+      <port type="output" prefix="cout" lib_name="CO" size="1"/>
+    </circuit_model>
+    <circuit_model type="hard_logic" name="dpram_1024x8" prefix="dpram_1024x8" spice_netlist="${OPENFPGA_PATH}/openfpga_flow/openfpga_cell_library/spice/dpram.sp" verilog_netlist="${OPENFPGA_PATH}/openfpga_flow/openfpga_cell_library/verilog/dpram8k.v">
+      <design_technology type="cmos"/>
+      <input_buffer exist="true" circuit_model_name="INVTX1"/>
+      <output_buffer exist="true" circuit_model_name="INVTX1"/>
+      <port type="input" prefix="waddr" size="10"/>
+      <port type="input" prefix="raddr" size="10"/>
+      <port type="input" prefix="data_in" size="8"/>
+      <port type="input" prefix="wen" size="1"/>
+      <port type="input" prefix="ren" size="1"/>
+      <port type="output" prefix="data_out" size="8"/>
+      <port type="clock" prefix="clk" size="1" is_global="true" default_val="0"/>
+    </circuit_model>
+  </circuit_library>
+  <configuration_protocol>
+    <organization type="scan_chain" circuit_model_name="DFFR"/>
+  </configuration_protocol>
+  <connection_block>
+    <switch name="ipin_cblock" circuit_model_name="mux_2level_tapbuf"/>
+  </connection_block>
+  <switch_block>
+    <switch name="0" circuit_model_name="mux_2level_tapbuf"/>
+  </switch_block>
+  <routing_segment>
+    <segment name="L4" circuit_model_name="chan_segment"/>
+  </routing_segment>
+  <direct_connection>
+    <direct name="adder_carry" circuit_model_name="direct_interc" type="column" x_dir="positive" y_dir="positive"/>
+  </direct_connection>
+  <pb_type_annotations>
+    <!-- physical pb_type binding in complex block IO -->
+    <pb_type name="io" physical_mode_name="physical" idle_mode_name="inpad"/>
+    <pb_type name="io[physical].iopad" circuit_model_name="GPIO" mode_bits="1"/> 
+    <pb_type name="io[inpad].inpad" physical_pb_type_name="io[physical].iopad" mode_bits="1"/> 
+    <pb_type name="io[outpad].outpad" physical_pb_type_name="io[physical].iopad" mode_bits="0"/> 
+    <!-- End physical pb_type binding in complex block IO -->
+
+    <!-- physical pb_type binding in complex block CLB -->
+    <!-- physical mode will be the default mode if not specified -->
+    <pb_type name="clb">
+      <!-- Binding interconnect to circuit models as their physical implementation, if not defined, we use the default model -->
+      <interconnect name="crossbar" circuit_model_name="mux_2level"/>
+    </pb_type>
+    <pb_type name="clb.fle" physical_mode_name="physical"/>
+    <pb_type name="clb.fle[physical].fabric.frac_logic.frac_lut6" circuit_model_name="frac_lut6" mode_bits="11"/>
+    <pb_type name="clb.fle[physical].fabric.ff" circuit_model_name="DFFSRQ"/>
+    <pb_type name="clb.fle[physical].fabric.adder" circuit_model_name="ADDF"/>
+    <!-- Binding operating pb_type to physical pb_type -->
+    <!-- Binding operating pb_types in mode 'n2_lut5' -->
+    <pb_type name="clb.fle[n2_lut5].ble5.lut5" physical_pb_type_name="clb.fle[physical].fabric.frac_logic.frac_lut6" mode_bits="01" physical_pb_type_index_factor="0.5">
+      <!-- Binding the lut5 to the first 5 inputs of fracturable lut6 -->
+      <port name="in" physical_mode_port="in[0:4]"/>
+      <port name="out" physical_mode_port="lut5_out[0:0]" physical_mode_pin_rotate_offset="1"/>
+    </pb_type>
+    <pb_type name="clb.fle[n2_lut5].ble5.ff" physical_pb_type_name="clb.fle[physical].fabric.ff"/>
+    <!-- Binding operating pb_types in mode 'arithmetic' -->
+    <pb_type name="clb.fle[arithmetic].arithmetic.lut4" physical_pb_type_name="clb.fle[physical].fabric.frac_logic.frac_lut6" mode_bits="11" physical_pb_type_index_factor="0.25">
+      <!-- Binding the lut4 to the first 4 inputs of fracturable lut6 -->
+      <port name="in" physical_mode_port="in[0:3]"/>
+      <port name="out" physical_mode_port="lut4_out[0:0]" physical_mode_pin_rotate_offset="1"/>
+    </pb_type>
+    <pb_type name="clb.fle[arithmetic].arithmetic.adder" physical_pb_type_name="clb.fle[physical].fabric.adder"/>
+    <pb_type name="clb.fle[arithmetic].arithmetic.ff" physical_pb_type_name="clb.fle[physical].fabric.ff"/>
+    <!-- Binding operating pb_types in mode 'ble6' -->
+    <pb_type name="clb.fle[n1_lut6].ble6.lut6" physical_pb_type_name="clb.fle[physical].fabric.frac_logic.frac_lut6" mode_bits="00">
+      <!-- Binding the lut6 to the first 6 inputs of fracturable lut6 -->
+      <port name="in" physical_mode_port="in[0:5]"/>
+      <port name="out" physical_mode_port="lut6_out"/>
+    </pb_type>
+    <pb_type name="clb.fle[n1_lut6].ble6.ff" physical_pb_type_name="clb.fle[physical].fabric.ff" physical_pb_type_index_factor="2" physical_pb_type_index_offset="0"/>
+    <!-- End physical pb_type binding in complex block clb -->
+
+
+    <!-- physical pb_type binding in complex block memory -->
+    <pb_type name="memory[mem_1024x8_dp].mem_1024x8_dp" circuit_model_name="dpram_1024x8"/>
+    <!-- END physical pb_type binding in complex block memory -->
+  </pb_type_annotations>
+</openfpga_architecture>
diff --git a/openfpga_flow/vpr_arch/k6_frac_N10_tileable_adder_chain_dpram8K_40nm.xml b/openfpga_flow/vpr_arch/k6_frac_N10_tileable_adder_chain_dpram8K_40nm.xml
new file mode 100644
index 000000000..d697a1e8d
--- /dev/null
+++ b/openfpga_flow/vpr_arch/k6_frac_N10_tileable_adder_chain_dpram8K_40nm.xml
@@ -0,0 +1,748 @@
+<!-- 
+  Flagship Heterogeneous Architecture with Carry Chains for VTR 7.0.
+
+  - 40 nm technology
+  - General purpose logic block: 
+    K = 6, N = 10, fracturable 6 LUTs (can operate as one 6-LUT or two 5-LUTs with 8 total FLE inputs (2 inputs of which are shared by the 5-LUTs) 
+    with optionally registered outputs
+    Each 5-LUT has an arithemtic mode that converts it to a single-bit adder with both inputs driven by 4-LUTs (both 4-LUTs share all 4 inputs)
+    Carry chain links to vertically adjacent logic blocks
+  - Memory size 32 Kbits, memory aspect ratios vary from a data width of 1 to data width of 64.  
+    Height = 6, found on every (8n+2)th column
+  - Multiplier modes: one 36x36, two 18x18, each 18x18 can also operate as two 9x9.  
+    Height = 4, found on every (8n+6)th column
+  - Routing architecture: L = 4, fc_in = 0.15, Fc_out = 0.1
+
+  Details on Modelling:
+
+  The electrical design of the architecture described here is NOT from an 
+  optimized, SPICED architecture.  Instead, we attempt to create a reasonable 
+  architecture file by using an existing commercial FPGA to approximate the area, 
+  delay, and power of the underlying components. This is combined with a reasonable 40 nm 
+  model of wiring and circuit design for low-level routing components, where available.
+  The resulting architecture has delays that roughly match a commercial 40 nm FPGA, but also 
+  has wiring electrical parameters that allow the wire lengths and switch patterns to be 
+  modified and you will still get reasonable delay results for the new architecture.
+  The following describes, in detail, how we obtained the various electrical values for this 
+  architecture.
+
+  Rmin for nmos and pmos, routing buffer sizes, and I/O pad delays are from the ifar 
+  architecture created by Ian Kuon: K06 N10 45nm fc 0.15 area-delay optimized architecture. 
+  (n10k06l04.fc15.area1delay1.cmos45nm.bptm.cmos45nm.xml)      
+  This routing architecture was optimized for 45 nm, and we have scaled it linearly to 40 nm to 
+  match the overall target (a 40 nm FPGA).
+
+  We obtain delay numbers by measuring delays of routing, soft logic blocks, 
+  memories, and multipliers from test circuits on a Stratix IV GX device 
+  (EP4SGX230DF29C2X, i.e. fastest speed grade). For routing, we took the average delay of H4 and V4 
+  wires.  Rmetal and Cmetal values for the routing wires were obtained from work done by Charles 
+  Chiasson. We use a 96 nm half-pitch (corresponding to mid-level metal stack 40 nm routing) and 
+  take the R and C data from the ITRS roadmap.  
+
+  For the general purpose logic block, we assume that the area and delays of the Stratix IV 
+  crossbar is close enough to the crossbar modelled here.  
+  Stratix IV uses 52 inputs and 20 feedback lines, but only a half-populated crossbar, leading to 
+  36:1 multiplexers.  We match these parameters in this architecture.
+
+  For LUTs, we include LUT 
+  delays measured from Stratix IV which is dependant on the input used (ie. some 
+  LUT inputs are faster than others).  The CAD tools at the time of VTR 7 does 
+  not consider differences in LUT input delays.
+
+  Adder delays obtained as approximate values from a Stratix IV EP4SE230F29C3 device.  
+  Delay obtained by compiling a 256 bit adder (registered inputs and outputs, 
+  all pins except clock virtual) then measuring the delays in chip-planner, 
+  sumout delay = 0.271ns to 0.348 ns, intra-block carry delay = 0.011 ns, 
+  inter-block carry delay = 0.327 ns.  Given this data, I will approximate 
+  sumout 0.3 ns, intra-block carry-delay = 0.01 ns, and 
+  inter-block carry-delay = 0.16 ns (since Altera inter-block carry delay has 
+  overhead that we don't have, I'll approximate the delay of a simpler chain at 
+  one half what they have.  This is very rough, anything from 0.01ns to 0.327ns 
+  can be justified).
+
+  Logic block area numbers obtained by scaling overall tile area of a 65nm 
+  Stratix III device, (as given in Wong, Betz and Rose, FPGA 2011) to 40 nm, then subtracting out 
+  routing area at a channel width of 300. We use a channel width of 300 because it can route 
+  all the VTR 6.0 benchmark circuits with an approximately 20% safety margin, and is also close to the
+  total channel width of Stratix IV. Hence this channel width is close to the commercial practice of
+  choosing a width that provides high routability. The architecture can be routed at different channel
+  widths, but we estimate the tile size and hence the physical length of routing wires assuming
+  a channel width of 300.
+
+  Sanity checks employed:
+    1.  We confirmed the routing buffer delay is ~1/3rd of total routing delay at L = 4. This matches 
+        common electrical design.
+
+
+  Authors: Jason Luu, Jeff Goeders, Vaughn Betz
+-->
+<architecture>
+  <!-- 
+       ODIN II specific config begins 
+       Describes the types of user-specified netlist blocks (in blif, this corresponds to 
+       ".model [type_of_block]") that this architecture supports.
+
+       Note: Basic LUTs, I/Os, and flip-flops are not included here as there are 
+       already special structures in blif (.names, .input, .output, and .latch) 
+       that describe them.
+  -->
+  <models>
+    <model name="adder">
+      <input_ports>
+        <port name="a" combinational_sink_ports="sumout cout"/>
+        <port name="b" combinational_sink_ports="sumout cout"/>
+        <port name="cin" combinational_sink_ports="sumout cout"/>
+      </input_ports>
+      <output_ports>
+        <port name="cout"/>
+        <port name="sumout"/>
+      </output_ports>
+    </model>
+    <!-- A virtual model for I/O to be used in the physical mode of io block -->
+    <model name="io">
+      <input_ports>
+        <port name="outpad"/>
+      </input_ports>
+      <output_ports>
+        <port name="inpad"/>
+      </output_ports>
+    </model>
+    <!-- A virtual model for I/O to be used in the physical mode of io block -->
+    <model name="frac_lut6">
+      <input_ports>
+        <port name="in"/>
+      </input_ports>
+      <output_ports>
+        <port name="lut4_out"/>
+        <port name="lut5_out"/>
+        <port name="lut6_out"/>
+      </output_ports>
+    </model>
+    <model name="dpram_1024x8">
+      <input_ports>
+        <!-- write address lines -->
+        <port name="waddr" clock="clk"/>
+        <!-- read address lines -->
+        <port name="raddr" clock="clk"/>
+        <!-- data lines can be broken down into smaller bit widths minimum size 1 -->
+        <port name="data_in" clock="clk"/>
+        <!-- write enable -->
+        <port name="wen" clock="clk"/>
+        <!-- read enable -->
+        <port name="ren" clock="clk"/>
+        <!-- memories are often clocked -->
+        <port name="clk" is_clock="1"/>
+      </input_ports>
+      <output_ports>
+        <!-- output can be broken down into smaller bit widths minimum size 1 -->
+        <port name="data_out" clock="clk"/>
+      </output_ports>
+    </model>
+  </models>
+  <tiles>
+    <tile name="io" capacity="8" area="0">
+      <equivalent_sites>
+        <site pb_type="io"/>
+      </equivalent_sites>
+      <input name="outpad" num_pins="1"/>
+      <output name="inpad" num_pins="1"/>
+      <fc in_type="frac" in_val="0.15" out_type="frac" out_val="0.10"/>
+      <pinlocations pattern="custom">
+        <loc side="left">io.outpad io.inpad</loc>
+        <loc side="top">io.outpad io.inpad</loc>
+        <loc side="right">io.outpad io.inpad</loc>
+        <loc side="bottom">io.outpad io.inpad</loc>
+      </pinlocations>
+    </tile>
+    <tile name="clb" area="53894">
+      <equivalent_sites>
+        <site pb_type="clb"/>
+      </equivalent_sites>
+      <input name="I" num_pins="40" equivalent="full"/>
+      <input name="cin" num_pins="1"/>
+      <output name="O" num_pins="20" equivalent="none"/>
+      <output name="cout" num_pins="1"/>
+      <clock name="clk" num_pins="1"/>
+      <fc in_type="frac" in_val="0.15" out_type="frac" out_val="0.10">
+        <fc_override port_name="cin" fc_type="frac" fc_val="0"/>
+        <fc_override port_name="cout" fc_type="frac" fc_val="0"/>
+      </fc>
+      <!--  Highly recommand to customize pin location when direct connection is used!!! -->
+      <!--pinlocations pattern="spread"/-->
+      <pinlocations pattern="custom">
+        <loc side="left">clb.clk</loc>
+        <loc side="top">clb.cin</loc>
+        <loc side="right">clb.O[9:0] clb.I[19:0]</loc>
+        <loc side="bottom">clb.cout clb.O[19:10] clb.I[39:20]</loc>
+      </pinlocations>
+    </tile>
+    <tile name="memory" height="2" area="548000">
+      <equivalent_sites>
+        <site pb_type="memory"/>
+      </equivalent_sites>
+      <input name="waddr" num_pins="10"/>
+      <input name="raddr" num_pins="10"/>
+      <input name="data_in" num_pins="8"/>
+      <input name="wen" num_pins="1"/>
+      <input name="ren" num_pins="1"/>
+      <output name="data_out" num_pins="8"/>
+      <clock name="clk" num_pins="1"/>
+      <fc in_type="frac" in_val="0.15" out_type="frac" out_val="0.10"/>
+      <!--pinlocations pattern="spread"/-->
+      <pinlocations pattern="custom">
+        <loc side="left">memory.clk</loc>
+        <loc side="top"></loc>
+        <loc side="right">memory.waddr[4:0] memory.raddr[4:0] memory.data_in[3:0] memory.wen memory.data_out[3:0]</loc>
+        <loc side="bottom">memory.waddr[9:5] memory.raddr[9:5] memory.data_in[7:4] memory.ren memory.data_out[7:4]</loc>
+      </pinlocations>
+    </tile>
+  </tiles>
+  <!-- ODIN II specific config ends -->
+  <!-- Physical descriptions begin -->
+  <layout tileable="true" through_channel="false">
+    <auto_layout aspect_ratio="1.0">
+      <!--Perimeter of 'io' blocks with 'EMPTY' blocks at corners-->
+      <perimeter type="io" priority="100"/>
+      <corners type="EMPTY" priority="101"/>
+      <!--Fill with 'clb'-->
+      <fill type="clb" priority="10"/>
+      <!--Column of 'memory' with 'EMPTY' blocks wherever a 'memory' does not fit. Vertical offset by 1 for perimeter.-->
+      <col type="memory" startx="2" starty="1" repeatx="8" priority="20"/>
+      <col type="EMPTY" startx="2" repeatx="8" starty="1" priority="19"/>
+    </auto_layout>
+    <fixed_layout name="3x2" width="5" height="4">
+      <!--Perimeter of 'io' blocks with 'EMPTY' blocks at corners-->
+      <perimeter type="io" priority="100"/>
+      <corners type="EMPTY" priority="101"/>
+      <!--Fill with 'clb'-->
+      <fill type="clb" priority="10"/>
+      <!--Column of 'memory' with 'EMPTY' blocks wherever a 'memory' does not fit. Vertical offset by 1 for perimeter.-->
+      <col type="memory" startx="2" starty="1" repeatx="8" priority="20"/>
+      <col type="EMPTY" startx="2" repeatx="8" starty="1" priority="19"/>
+    </fixed_layout>
+  </layout>
+  <device>
+    <!-- VB & JL: Using Ian Kuon's transistor sizing and drive strength data for routing, at 40 nm. Ian used BPTM 
+			     models. We are modifying the delay values however, to include metal C and R, which allows more architecture
+			     experimentation. We are also modifying the relative resistance of PMOS to be 1.8x that of NMOS
+			     (vs. Ian's 3x) as 1.8x lines up with Jeff G's data from a 45 nm process (and is more typical of 
+			     45 nm in general). I'm upping the Rmin_nmos from Ian's just over 6k to nearly 9k, and dropping 
+			     RminW_pmos from 18k to 16k to hit this 1.8x ratio, while keeping the delays of buffers approximately
+			     lined up with Stratix IV. 
+			     We are using Jeff G.'s capacitance data for 45 nm (in tech/ptm_45nm).
+			     Jeff's tables list C in for transistors with widths in multiples of the minimum feature size (45 nm).
+			     The minimum contactable transistor is 2.5 * 45 nm, so I need to multiply drive strength sizes in this file
+	                     by 2.5x when looking up in Jeff's tables.
+			     The delay values are lined up with Stratix IV, which has an architecture similar to this
+			     proposed FPGA, and which is also 40 nm 
+			     C_ipin_cblock: input capacitance of a track buffer, which VPR assumes is a single-stage
+			     4x minimum drive strength buffer. -->
+    <sizing R_minW_nmos="8926" R_minW_pmos="16067"/>
+    <!-- The grid_logic_tile_area below will be used for all blocks that do not explicitly set their own (non-routing)
+     	  area; set to 0 since we explicitly set the area of all blocks currently in this architecture file.
+	    -->
+    <area grid_logic_tile_area="0"/>
+    <chan_width_distr>
+      <x distr="uniform" peak="1.000000"/>
+      <y distr="uniform" peak="1.000000"/>
+    </chan_width_distr>
+    <switch_block type="wilton" fs="3"/>
+    <connection_block input_switch_name="ipin_cblock"/>
+  </device>
+  <switchlist>
+    <!-- VB: the mux_trans_size and buf_size data below is in minimum width transistor *areas*, assuming the purple
+           book area formula. This means the mux transistors are about 5x minimum drive strength.
+           We assume the first stage of the buffer is 3x min drive strength to be reasonable given the large 
+           mux transistors, and this gives a reasonable stage ratio of a bit over 5x to the second stage. We assume
+           the n and p transistors in the first stage are equal-sized to lower the buffer trip point, since it's fed
+           by a pass transistor mux. We can then reverse engineer the buffer second stage to hit the specified 
+           buf_size (really buffer area) - 16.2x minimum drive nmos and 1.8*16.2 = 29.2x minimum drive.
+           I then took the data from Jeff G.'s PTM modeling of 45 nm to get the Cin (gate of first stage) and Cout 
+           (diff of second stage) listed below.  Jeff's models are in tech/ptm_45nm, and are in min feature multiples.
+           The minimum contactable transistor is 2.5 * 45 nm, so I need to multiply the drive strength sizes above by 
+           2.5x when looking up in Jeff's tables.
+           Finally, we choose a switch delay (58 ps) that leads to length 4 wires having a delay equal to that of SIV of 126 ps.
+           This also leads to the switch being 46% of the total wire delay, which is reasonable. -->
+    <switch type="mux" name="0" R="551" Cin=".77e-15" Cout="4e-15" Tdel="58e-12" mux_trans_size="2.630740" buf_size="27.645901"/>
+    <!--switch ipin_cblock resistance set to yeild for 4x minimum drive strength buffer-->
+    <switch type="mux" name="ipin_cblock" R="2231.5" Cout="0." Cin="1.47e-15" Tdel="7.247000e-11" mux_trans_size="1.222260" buf_size="auto"/>
+  </switchlist>
+  <segmentlist>
+    <!--- VB & JL: using ITRS metal stack data, 96 nm half pitch wires, which are intermediate metal width/space.  
+             With the 96 nm half pitch, such wires would take 60 um of height, vs. a 90 nm high (approximated as square) Stratix IV tile so this seems
+             reasonable. Using a tile length of 90 nm, corresponding to the length of a Stratix IV tile if it were square. -->
+    <!-- GIVE a specific name for the segment! OpenFPGA appreciate that! -->
+    <segment name="L4" freq="1.000000" length="4" type="unidir" Rmetal="101" Cmetal="22.5e-15">
+      <mux name="0"/>
+      <sb type="pattern">1 1 1 1 1</sb>
+      <cb type="pattern">1 1 1 1</cb>
+    </segment>
+  </segmentlist>
+  <directlist>
+    <direct name="adder_carry" from_pin="clb.cout" to_pin="clb.cin" x_offset="0" y_offset="-1" z_offset="0"/>
+  </directlist>
+  <complexblocklist>
+    <!-- Define I/O pads begin -->
+    <!-- Capacity is a unique property of I/Os, it is the maximum number of I/Os that can be placed at the same (X,Y) location on the FPGA -->
+    <!-- Not sure of the area of an I/O (varies widely), and it's not relevant to the design of the FPGA core, so we're setting it to 0. -->
+    <pb_type name="io">
+      <input name="outpad" num_pins="1"/>
+      <output name="inpad" num_pins="1"/>
+
+      <!-- Do NOT add clock pins to I/O here!!! VPR does not build clock network in the way that OpenFPGA can support
+           If you need to register the I/O, define clocks in the circuit models
+           These clocks can be handled in back-end
+       -->
+      <!-- A mode denotes the physical implementation of an I/O 
+           This mode will be not packable but is mainly used for fabric verilog generation   
+        -->
+      <mode name="physical" disable_packing="true">
+        <pb_type name="iopad" blif_model=".subckt io" num_pb="1">
+          <input name="outpad" num_pins="1"/>
+          <output name="inpad" num_pins="1"/>
+        </pb_type>
+        <interconnect>
+          <direct name="outpad" input="io.outpad" output="iopad.outpad">
+            <delay_constant max="1.394e-11" in_port="io.outpad" out_port="iopad.outpad"/>
+          </direct>
+          <direct name="inpad" input="iopad.inpad" output="io.inpad">
+            <delay_constant max="4.243e-11" in_port="iopad.inpad" out_port="io.inpad"/>
+          </direct>
+        </interconnect>
+      </mode>
+
+      <!-- IOs can operate as either inputs or outputs.
+	     Delays below come from Ian Kuon. They are small, so they should be interpreted as
+	     the delays to and from registers in the I/O (and generally I/Os are registered 
+	     today and that is when you timing analyze them.
+	     -->
+      <mode name="inpad">
+        <pb_type name="inpad" blif_model=".input" num_pb="1">
+          <output name="inpad" num_pins="1"/>
+        </pb_type>
+        <interconnect>
+          <direct name="inpad" input="inpad.inpad" output="io.inpad">
+            <delay_constant max="4.243e-11" in_port="inpad.inpad" out_port="io.inpad"/>
+          </direct>
+        </interconnect>
+      </mode>
+      <mode name="outpad">
+        <pb_type name="outpad" blif_model=".output" num_pb="1">
+          <input name="outpad" num_pins="1"/>
+        </pb_type>
+        <interconnect>
+          <direct name="outpad" input="io.outpad" output="outpad.outpad">
+            <delay_constant max="1.394e-11" in_port="io.outpad" out_port="outpad.outpad"/>
+          </direct>
+        </interconnect>
+      </mode>
+      <!-- Every input pin is driven by 15% of the tracks in a channel, every output pin is driven by 10% of the tracks in a channel -->
+      <!-- IOs go on the periphery of the FPGA, for consistency, 
+          make it physically equivalent on all sides so that only one definition of I/Os is needed.
+          If I do not make a physically equivalent definition, then I need to define 4 different I/Os, one for each side of the FPGA
+        -->
+      <!-- Place I/Os on the sides of the FPGA -->
+      <power method="ignore"/>
+    </pb_type>
+    <!-- Define I/O pads ends -->
+    <!-- Define general purpose logic block (CLB) begin -->
+    <!--- Area calculation: Total Stratix IV tile area is about 8100 um^2, and a minimum width transistor 
+	   area is 60 L^2 yields a tile area of 84375 MWTAs.
+	   Routing at W=300 is 30481 MWTAs, leaving us with a total of 53000 MWTAs for logic block area 
+	   This means that only 37% of our area is in the general routing, and 63% is inside the logic
+	   block. Note that the crossbar / local interconnect is considered part of the logic block
+	   area in this analysis. That is a lower proportion of of routing area than most academics
+	   assume, but note that the total routing area really includes the crossbar, which would push
+	   routing area up significantly, we estimate into the ~70% range. 
+	   -->
+    <pb_type name="clb">
+      <input name="I" num_pins="40" equivalent="full"/>
+      <input name="cin" num_pins="1"/>
+      <output name="O" num_pins="20" equivalent="none"/>
+      <output name="cout" num_pins="1"/>
+      <clock name="clk" num_pins="1"/>
+      <!-- Describe fracturable logic element.  
+             Each fracturable logic element has a 6-LUT that can alternatively operate as two 5-LUTs with shared inputs. 
+             The outputs of the fracturable logic element can be optionally registered
+        -->
+      <pb_type name="fle" num_pb="10">
+        <input name="in" num_pins="6"/>
+        <input name="cin" num_pins="1"/>
+        <output name="out" num_pins="2"/>
+        <output name="cout" num_pins="1"/>
+        <clock name="clk" num_pins="1"/>
+        <!-- Physical mode definition begin (physical implementation of the fle) -->
+        <mode name="physical" disable_packing="true">
+          <pb_type name="fabric" num_pb="1">
+            <input name="in" num_pins="6"/>
+            <input name="cin" num_pins="1"/>
+            <output name="out" num_pins="2"/>
+            <output name="cout" num_pins="1"/>
+            <clock name="clk" num_pins="1"/>
+            <pb_type name="frac_logic" num_pb="1">
+              <input name="in" num_pins="6"/>
+              <output name="lut4_out" num_pins="4"/>
+              <output name="out" num_pins="2"/>
+              <!-- Define LUT -->
+              <pb_type name="frac_lut6" blif_model=".subckt frac_lut6" num_pb="1">
+                <input name="in" num_pins="6"/>
+                <output name="lut4_out" num_pins="4"/>
+                <output name="lut5_out" num_pins="2"/>
+                <output name="lut6_out" num_pins="1"/>
+              </pb_type>
+              <interconnect>
+                <direct name="direct1" input="frac_logic.in" output="frac_lut6.in"/>
+                <direct name="direct2" input="frac_lut6.lut4_out" output="frac_logic.lut4_out"/>
+                <direct name="direct3" input="frac_lut6.lut5_out[1]" output="frac_logic.out[1]"/>
+                <!-- Xifan Tang: I use out[0] because the output of lut6 in lut6 mode is wired to the out[0] -->
+                <mux name="mux1" input="frac_lut6.lut6_out frac_lut6.lut5_out[0]" output="frac_logic.out[0]"/>
+              </interconnect>
+            </pb_type>
+            <!-- Define flip-flop -->
+            <pb_type name="ff" blif_model=".latch" num_pb="2" class="flipflop">
+              <input name="D" num_pins="1" port_class="D"/>
+              <output name="Q" num_pins="1" port_class="Q"/>
+              <clock name="clk" num_pins="1" port_class="clock"/>
+              <T_setup value="66e-12" port="ff.D" clock="clk"/>
+              <T_clock_to_Q max="124e-12" port="ff.Q" clock="clk"/>
+            </pb_type>         
+            <!-- Define adders -->
+            <pb_type name="adder" blif_model=".subckt adder" num_pb="2">
+              <input name="a" num_pins="1"/>
+              <input name="b" num_pins="1"/>
+              <input name="cin" num_pins="1"/>
+              <output name="cout" num_pins="1"/>
+              <output name="sumout" num_pins="1"/>
+              <delay_constant max="0.3e-9" in_port="adder.a" out_port="adder.sumout"/>
+              <delay_constant max="0.3e-9" in_port="adder.b" out_port="adder.sumout"/>
+              <delay_constant max="0.3e-9" in_port="adder.cin" out_port="adder.sumout"/>
+              <delay_constant max="0.3e-9" in_port="adder.a" out_port="adder.cout"/>
+              <delay_constant max="0.3e-9" in_port="adder.b" out_port="adder.cout"/>
+              <delay_constant max="0.01e-9" in_port="adder.cin" out_port="adder.cout"/>
+            </pb_type>
+            <interconnect>
+              <direct name="direct1" input="fabric.in" output="frac_logic.in"/>
+              <direct name="direct2" input="frac_logic.out[1:0]" output="ff[1:0].D"/>
+              <direct name="direct3" input="fabric.cin" output="adder[0:0].cin"/>
+              <direct name="direct4" input="adder[0:0].cout" output="adder[1:1].cin"/>
+              <direct name="direct5" input="adder[1:1].cout" output="fabric.cout"/>
+              <direct name="direct6" input="frac_logic.lut4_out[0:0]" output="adder[0:0].a"/>
+              <direct name="direct7" input="frac_logic.lut4_out[1:1]" output="adder[0:0].b"/>
+              <direct name="direct8" input="frac_logic.lut4_out[2:2]" output="adder[1:1].a"/>
+              <direct name="direct9" input="frac_logic.lut4_out[3:3]" output="adder[1:1].b"/>
+              <complete name="direct10" input="fabric.clk" output="ff[1:0].clk"/>
+              <mux name="mux1" input="adder[0].sumout ff[0].Q frac_logic.out[0]" output="fabric.out[0]">
+                <!-- LUT to output is faster than FF to output on a Stratix IV -->
+                <delay_constant max="25e-12" in_port="frac_logic.out[0]" out_port="fabric.out[0]"/>
+                <delay_constant max="45e-12" in_port="ff[0].Q" out_port="fabric.out[0]"/>
+              </mux>
+              <mux name="mux2" input="adder[1].sumout ff[1].Q frac_logic.out[1]" output="fabric.out[1]">
+                <!-- LUT to output is faster than FF to output on a Stratix IV -->
+                <delay_constant max="25e-12" in_port="frac_logic.out[1]" out_port="fabric.out[1]"/>
+                <delay_constant max="45e-12" in_port="ff[1].Q" out_port="fabric.out[1]"/>
+              </mux>
+            </interconnect>
+          </pb_type>
+          <interconnect>
+            <direct name="direct1" input="fle.in" output="fabric.in"/>
+            <direct name="direct2" input="fle.cin" output="fabric.cin"/>
+            <direct name="direct3" input="fabric.out" output="fle.out"/>
+            <direct name="direct4" input="fabric.cout" output="fle.cout"/>
+            <direct name="direct5" input="fle.clk" output="fabric.clk"/>
+          </interconnect>
+        </mode>
+        <!-- Physical mode definition end (physical implementation of the fle) -->
+        <!-- BEGIN fle mode of dual lut5 -->
+        <mode name="n2_lut5">
+          <pb_type name="ble5" num_pb="2">
+            <input name="in" num_pins="5"/>
+            <output name="out" num_pins="1"/>
+            <clock name="clk" num_pins="1"/>
+            <!-- Regular LUT mode -->
+            <pb_type name="lut5" blif_model=".names" num_pb="1" class="lut">
+              <input name="in" num_pins="5" port_class="lut_in"/>
+              <output name="out" num_pins="1" port_class="lut_out"/>
+              <!-- LUT timing using delay matrix -->
+              <!-- These are the physical delay inputs on a Stratix IV LUT but because VPR cannot do LUT rebalancing,
+                  we instead take the average of these numbers to get more stable results
+                82e-12
+                173e-12
+                261e-12
+                263e-12
+                398e-12
+                -->
+              <delay_matrix type="max" in_port="lut5.in" out_port="lut5.out">
+                235e-12
+                235e-12
+                235e-12
+                235e-12
+                235e-12
+              </delay_matrix>
+            </pb_type>
+            <pb_type name="ff" blif_model=".latch" num_pb="1" class="flipflop">
+              <input name="D" num_pins="1" port_class="D"/>
+              <output name="Q" num_pins="1" port_class="Q"/>
+              <clock name="clk" num_pins="1" port_class="clock"/>
+              <T_setup value="66e-12" port="ff.D" clock="clk"/>
+              <T_clock_to_Q max="124e-12" port="ff.Q" clock="clk"/>
+            </pb_type>
+            <interconnect>
+              <direct name="direct1" input="ble5.in" output="lut5.in"/>
+              <direct name="direct2" input="lut5.out" output="ff.D">
+                <pack_pattern name="ble5" in_port="lut5.out" out_port="ff.D"/>
+              </direct>
+              <direct name="direct3" input="ble5.clk" output="ff.clk"/>
+              <mux name="mux1" input="ff.Q lut5.out" output="ble5.out">
+                <delay_constant max="25e-12" in_port="lut5.out" out_port="ble5.out"/>
+                <delay_constant max="45e-12" in_port="ff.Q" out_port="ble5.out"/>
+              </mux>
+            </interconnect>
+          </pb_type>
+          <interconnect>
+            <direct name="direct1" input="fle.in[4:0]" output="ble5[0:0].in"/>
+            <direct name="direct2" input="fle.in[4:0]" output="ble5[1:1].in"/>
+            <complete name="direct3" input="fle.clk" output="ble5.clk"/>
+            <direct name="direct4" input="ble5.out" output="fle.out"/>
+          </interconnect>
+        </mode>
+        <!-- END fle mode of dual lut5 -->
+        <!-- BEGIN arithmetic mode of dual lut4 + adders -->
+        <mode name="arithmetic">
+          <pb_type name="arithmetic" num_pb="2">
+            <input name="in" num_pins="4"/>
+            <input name="cin" num_pins="1"/>
+            <output name="out" num_pins="1"/>
+            <output name="cout" num_pins="1"/>
+            <clock name="clk" num_pins="1"/>
+            <!-- Special dual-LUT mode that drives adder only -->
+            <pb_type name="lut4" blif_model=".names" num_pb="2" class="lut">
+              <input name="in" num_pins="4" port_class="lut_in"/>
+              <output name="out" num_pins="1" port_class="lut_out"/>
+              <!-- LUT timing using delay matrix -->
+              <!-- These are the physical delay inputs on a Stratix IV LUT but because VPR cannot do LUT rebalancing,
+                       we instead take the average of these numbers to get more stable results
+                  82e-12
+                  173e-12
+                  261e-12
+                  263e-12
+                  -->
+              <delay_matrix type="max" in_port="lut4.in" out_port="lut4.out">
+                  195e-12
+                  195e-12
+                  195e-12
+                  195e-12
+                </delay_matrix>
+            </pb_type>
+            <pb_type name="adder" blif_model=".subckt adder" num_pb="1">
+              <input name="a" num_pins="1"/>
+              <input name="b" num_pins="1"/>
+              <input name="cin" num_pins="1"/>
+              <output name="cout" num_pins="1"/>
+              <output name="sumout" num_pins="1"/>
+              <delay_constant max="0.3e-9" in_port="adder.a" out_port="adder.sumout"/>
+              <delay_constant max="0.3e-9" in_port="adder.b" out_port="adder.sumout"/>
+              <delay_constant max="0.3e-9" in_port="adder.cin" out_port="adder.sumout"/>
+              <delay_constant max="0.3e-9" in_port="adder.a" out_port="adder.cout"/>
+              <delay_constant max="0.3e-9" in_port="adder.b" out_port="adder.cout"/>
+              <delay_constant max="0.01e-9" in_port="adder.cin" out_port="adder.cout"/>
+            </pb_type>
+            <pb_type name="ff" blif_model=".latch" num_pb="1" class="flipflop">
+              <input name="D" num_pins="1" port_class="D"/>
+              <output name="Q" num_pins="1" port_class="Q"/>
+              <clock name="clk" num_pins="1" port_class="clock"/>
+              <T_setup value="66e-12" port="ff.D" clock="clk"/>
+              <T_clock_to_Q max="124e-12" port="ff.Q" clock="clk"/>
+            </pb_type>
+            <interconnect>
+              <direct name="clock" input="arithmetic.clk" output="ff.clk"/>
+              <direct name="lut_in1" input="arithmetic.in[3:0]" output="lut4[0:0].in[3:0]"/>
+              <direct name="lut_in2" input="arithmetic.in[3:0]" output="lut4[1:1].in[3:0]"/>
+              <direct name="lut_to_add1" input="lut4[0:0].out" output="adder.a">
+                </direct>
+              <direct name="lut_to_add2" input="lut4[1:1].out" output="adder.b">
+                </direct>
+              <direct name="add_to_ff" input="adder.sumout" output="ff.D">
+                <pack_pattern name="chain" in_port="adder.sumout" out_port="ff.D"/>
+              </direct>
+              <direct name="carry_in" input="arithmetic.cin" output="adder.cin">
+                <pack_pattern name="chain" in_port="arithmetic.cin" out_port="adder.cin"/>
+              </direct>
+              <direct name="carry_out" input="adder.cout" output="arithmetic.cout">
+                <pack_pattern name="chain" in_port="adder.cout" out_port="arithmetic.cout"/>
+              </direct>
+              <mux name="sumout" input="ff.Q adder.sumout" output="arithmetic.out">
+                <delay_constant max="25e-12" in_port="adder.sumout" out_port="arithmetic.out"/>
+                <delay_constant max="45e-12" in_port="ff.Q" out_port="arithmetic.out"/>
+              </mux>
+            </interconnect>
+          </pb_type>
+          <interconnect>
+            <direct name="direct1" input="fle.in[3:0]" output="arithmetic[0:0].in"/>
+            <direct name="direct2" input="fle.in[3:0]" output="arithmetic[1:1].in"/>
+            <direct name="carry_in" input="fle.cin" output="arithmetic[0:0].cin">
+              <pack_pattern name="chain" in_port="fle.cin" out_port="arithmetic[0:0].cin"/>
+            </direct>
+            <direct name="carry_inter" input="arithmetic[0:0].cout" output="arithmetic[1:1].cin">
+              <pack_pattern name="chain" in_port="arithmetic[0:0].cout" out_port="arithmetic[1:1].cin"/>
+            </direct>
+            <direct name="carry_out" input="arithmetic[1:1].cout" output="fle.cout">
+              <pack_pattern name="chain" in_port="arithmetic.cout" out_port="fle.cout"/>
+            </direct>
+            <complete name="direct3" input="fle.clk" output="arithmetic.clk"/>
+            <direct name="direct4" input="arithmetic.out" output="fle.out"/>
+          </interconnect>
+        </mode>
+        <!-- n2_lut5 -->
+        <mode name="n1_lut6">
+          <pb_type name="ble6" num_pb="1">
+            <input name="in" num_pins="6"/>
+            <output name="out" num_pins="1"/>
+            <clock name="clk" num_pins="1"/>
+            <pb_type name="lut6" blif_model=".names" num_pb="1" class="lut">
+              <input name="in" num_pins="6" port_class="lut_in"/>
+              <output name="out" num_pins="1" port_class="lut_out"/>
+              <!-- LUT timing using delay matrix -->
+              <!-- These are the physical delay inputs on a Stratix IV LUT but because VPR cannot do LUT rebalancing,
+                       we instead take the average of these numbers to get more stable results
+                  82e-12
+                  173e-12
+                  261e-12
+                  263e-12
+                  398e-12
+                  397e-12
+                  -->
+              <delay_matrix type="max" in_port="lut6.in" out_port="lut6.out">
+                  261e-12
+                  261e-12
+                  261e-12
+                  261e-12
+                  261e-12
+                  261e-12
+                </delay_matrix>
+            </pb_type>
+            <pb_type name="ff" blif_model=".latch" num_pb="1" class="flipflop">
+              <input name="D" num_pins="1" port_class="D"/>
+              <output name="Q" num_pins="1" port_class="Q"/>
+              <clock name="clk" num_pins="1" port_class="clock"/>
+              <T_setup value="66e-12" port="ff.D" clock="clk"/>
+              <T_clock_to_Q max="124e-12" port="ff.Q" clock="clk"/>
+            </pb_type>
+            <interconnect>
+              <direct name="direct1" input="ble6.in" output="lut6[0:0].in"/>
+              <direct name="direct2" input="lut6.out" output="ff.D">
+                <pack_pattern name="ble6" in_port="lut6.out" out_port="ff.D"/>
+              </direct>
+              <direct name="direct3" input="ble6.clk" output="ff.clk"/>
+              <mux name="mux1" input="ff.Q lut6.out" output="ble6.out">
+                <delay_constant max="25e-12" in_port="lut6.out" out_port="ble6.out"/>
+                <delay_constant max="45e-12" in_port="ff.Q" out_port="ble6.out"/>
+              </mux>
+            </interconnect>
+          </pb_type>
+          <interconnect>
+            <direct name="direct1" input="fle.in[5:0]" output="ble6.in"/>
+            <direct name="direct2" input="ble6.out" output="fle.out[0:0]"/>
+            <direct name="direct3" input="fle.clk" output="ble6.clk"/>
+          </interconnect>
+        </mode>
+        <!-- n1_lut6 -->
+      </pb_type>
+      <interconnect>
+        <!-- We use a 50% depop crossbar built using small full xbars to get sets of logically equivalent pins at inputs of CLB 
+           The delays below come from Stratix IV. the delay through a connection block
+           input mux + the crossbar in Stratix IV is 167 ps. We already have a 72 ps 
+           delay on the connection block input mux (modeled by Ian Kuon), so the remaining
+           delay within the crossbar is 95 ps. 
+           The delays of cluster feedbacks in Stratix IV is 100 ps, when driven by a LUT.
+           Since all our outputs LUT outputs go to a BLE output, and have a delay of 
+           25 ps to do so, we subtract 25 ps from the 100 ps delay of a feedback
+           to get the part that should be marked on the crossbar.	 -->
+        <complete name="crossbar" input="clb.I fle[9:0].out" output="fle[9:0].in">
+          <delay_constant max="95e-12" in_port="clb.I" out_port="fle[9:0].in"/>
+          <delay_constant max="75e-12" in_port="fle[9:0].out" out_port="fle[9:0].in"/>
+        </complete>
+
+        <complete name="clks" input="clb.clk" output="fle[9:0].clk">
+        </complete>
+        <!-- This way of specifying direct connection to clb outputs is important because this architecture uses automatic spreading of opins.  
+                 By grouping to output pins in this fashion, if a logic block is completely filled by 6-LUTs, 
+                 then the outputs those 6-LUTs take get evenly distributed across all four sides of the CLB instead of clumped on two sides (which is what happens with a more
+                 naive specification).
+          -->
+        <direct name="clbouts1" input="fle[9:0].out[0:0]" output="clb.O[9:0]"/>
+        <direct name="clbouts2" input="fle[9:0].out[1:1]" output="clb.O[19:10]"/>
+        <!-- Carry chain links -->
+        <direct name="carry_in" input="clb.cin" output="fle[0:0].cin">
+          <!-- Put all inter-block carry chain delay on this one edge -->
+          <delay_constant max="0.16e-9" in_port="clb.cin" out_port="fle[0:0].cin"/>
+          <pack_pattern name="chain" in_port="clb.cin" out_port="fle[0:0].cin"/>
+        </direct>
+        <direct name="carry_out" input="fle[9:9].cout" output="clb.cout">
+          <pack_pattern name="chain" in_port="fle[9:9].cout" out_port="clb.cout"/>
+        </direct>
+        <direct name="carry_link" input="fle[8:0].cout" output="fle[9:1].cin">
+          <pack_pattern name="chain" in_port="fle[8:0].cout" out_port="fle[9:1].cin"/>
+        </direct>
+      </interconnect>
+    </pb_type>
+    <!-- Define general purpose logic block (CLB) ends -->
+    <!-- Define single-mode dual-port memory begin -->
+    <pb_type name="memory">
+      <input name="waddr" num_pins="10"/>
+      <input name="raddr" num_pins="10"/>
+      <input name="data_in" num_pins="8"/>
+      <input name="wen" num_pins="1"/>
+      <input name="ren" num_pins="1"/>
+      <output name="data_out" num_pins="8"/>
+      <clock name="clk" num_pins="1"/>
+      <!-- Specify the 1024x8=8Kbit memory block
+           Note: the delay numbers are extracted from VPR flagship XML without modification
+                 Should align to the process technology we using to create the 16K dual-port RAM
+        -->
+      <mode name="mem_1024x8_dp">
+        <pb_type name="mem_1024x8_dp" blif_model=".subckt dpram_1024x8" num_pb="1">
+          <input name="waddr" num_pins="10" port_class="address1"/>
+          <input name="raddr" num_pins="10" port_class="address2"/>
+          <input name="data_in" num_pins="8" port_class="data_in1"/>
+          <input name="wen" num_pins="1" port_class="write_en1"/>
+          <input name="ren" num_pins="1" port_class="write_en2"/>
+          <output name="data_out" num_pins="8" port_class="data_out1"/>
+          <clock name="clk" num_pins="1" port_class="clock"/>
+          <T_setup value="509e-12" port="mem_1024x8_dp.waddr" clock="clk"/>
+          <T_setup value="509e-12" port="mem_1024x8_dp.raddr" clock="clk"/>
+          <T_setup value="509e-12" port="mem_1024x8_dp.data_in" clock="clk"/>
+          <T_setup value="509e-12" port="mem_1024x8_dp.wen" clock="clk"/>
+          <T_setup value="509e-12" port="mem_1024x8_dp.ren" clock="clk"/>
+          <T_clock_to_Q max="1.234e-9" port="mem_1024x8_dp.data_out" clock="clk"/>
+          <power method="pin-toggle">
+            <port name="clk" energy_per_toggle="17.9e-12"/>
+            <static_power power_per_instance="0.0"/>
+          </power>
+        </pb_type>
+        <interconnect>
+          <direct name="waddress" input="memory.waddr" output="mem_1024x8_dp.waddr">
+            <delay_constant max="132e-12" in_port="memory.waddr" out_port="mem_1024x8_dp.waddr"/>
+          </direct>
+          <direct name="raddress" input="memory.raddr" output="mem_1024x8_dp.raddr">
+            <delay_constant max="132e-12" in_port="memory.raddr" out_port="mem_1024x8_dp.raddr"/>
+          </direct>
+          <direct name="data_input" input="memory.data_in" output="mem_1024x8_dp.data_in">
+            <delay_constant max="132e-12" in_port="memory.data_in" out_port="mem_1024x8_dp.data_in"/>
+          </direct>
+          <direct name="writeen" input="memory.wen" output="mem_1024x8_dp.wen">
+            <delay_constant max="132e-12" in_port="memory.wen" out_port="mem_1024x8_dp.wen"/>
+          </direct>
+          <direct name="readen" input="memory.ren" output="mem_1024x8_dp.ren">
+            <delay_constant max="132e-12" in_port="memory.ren" out_port="mem_1024x8_dp.ren"/>
+          </direct>
+          <direct name="dataout" input="mem_1024x8_dp.data_out" output="memory.data_out">
+            <delay_constant max="40e-12" in_port="mem_1024x8_dp.data_out" out_port="memory.data_out"/>
+          </direct>
+          <direct name="clk" input="memory.clk" output="mem_1024x8_dp.clk">
+          </direct>
+        </interconnect>
+      </mode>
+    </pb_type>
+    <!-- Define single-mode dual-port memory end -->
+  </complexblocklist>
+</architecture>