Merge branch 'master' into tutorials

libopenfpga/libpcf/src/pin_constraints.cpp

@@ -38,6 +38,28 @@ std::string PinConstraints::net(const PinConstraintId& pin_constraint_id) const
   return pin_constraint_nets_[pin_constraint_id]; 
 }
 
+std::string PinConstraints::pin_net(const openfpga::BasicPort& pin) const {
+  std::string constrained_net_name;
+  for (const PinConstraintId& pin_constraint : pin_constraints()) {
+    if (pin == pin_constraint_pins_[pin_constraint]) {
+      constrained_net_name = net(pin_constraint); 
+      break;
+    }
+  }
+  return constrained_net_name;
+}
+
+openfpga::BasicPort PinConstraints::net_pin(const std::string& net) const {
+  openfpga::BasicPort constrained_pin;
+  for (const PinConstraintId& pin_constraint : pin_constraints()) {
+    if (net == pin_constraint_nets_[pin_constraint]) {
+      constrained_pin = pin(pin_constraint); 
+      break;
+    }
+  }
+  return constrained_pin;
+} 
+
 bool PinConstraints::empty() const {
   return 0 == pin_constraint_ids_.size();
 }
@@ -70,3 +92,11 @@ PinConstraintId PinConstraints::create_pin_constraint(const openfpga::BasicPort&
 bool PinConstraints::valid_pin_constraint_id(const PinConstraintId& pin_constraint_id) const {
   return ( size_t(pin_constraint_id) < pin_constraint_ids_.size() ) && ( pin_constraint_id == pin_constraint_ids_[pin_constraint_id] ); 
 }
+
+bool PinConstraints::unconstrained_net(const std::string& net) const {
+  return net.empty();
+}
+
+bool PinConstraints::unmapped_net(const std::string& net) const {
+  return std::string(PIN_CONSTRAINT_OPEN_NET) == net;
+}

libopenfpga/libpcf/src/pin_constraints.h

@@ -52,11 +52,21 @@ class PinConstraints {
     /* Get the net to be constrained */
     std::string net(const PinConstraintId& pin_constraint_id) const;
 
+    /* Find the net that is constrained on a pin
+     * TODO: this function will only return the first net found in the constraint list    
+     */
+    std::string pin_net(const openfpga::BasicPort& pin) const;
+
+    /* Find the pin that a net is constrained to
+     * If not found, the return port will be an invalid BasicPort
+     * TODO: this function will only return the first pin found in the constraint list    
+     */
+    openfpga::BasicPort net_pin(const std::string& net) const; 
+
     /* Check if there are any pin constraints */
     bool empty() const;
 
   public: /* Public Mutators */
-
     /* Reserve a number of design constraints to be memory efficent */
     void reserve_pin_constraints(const size_t& num_pin_constraints);
 
@@ -65,7 +75,22 @@ class PinConstraints {
                                           const std::string& net);
 
   public: /* Public invalidators/validators */
+    /* Show if the pin constraint id is a valid for data queries */
     bool valid_pin_constraint_id(const PinConstraintId& pin_constraint_id) const;
+
+    /* Show if the net has no constraints (free to map to any pin) 
+     * This function is used to identify the net name returned by APIs:
+     * - pin_net()
+     * - net()
+     */
+    bool unconstrained_net(const std::string& net) const;
+
+    /* Show if the net is defined specifically not to map to any pin 
+     * This function is used to identify the net name returned by APIs:
+     * - pin_net()
+     * - net()
+     */
+    bool unmapped_net(const std::string& net) const;
   private: /* Internal data */
     /* Unique ids for each design constraint */
     vtr::vector<PinConstraintId, PinConstraintId> pin_constraint_ids_;

openfpga/src/fpga_verilog/verilog_api.cpp

@@ -203,6 +203,8 @@ int fpga_verilog_testbench(const ModuleManager &module_manager,
                                        random_top_testbench_file_path,
                                        atom_ctx,
                                        netlist_annotation,
+                                       module_manager,
+                                       fabric_global_port_info,
                                        pin_constraints,
                                        simulation_setting,
                                        options.explicit_port_mapping());

openfpga/src/fpga_verilog/verilog_formal_random_top_testbench.cpp

@@ -19,6 +19,7 @@
 
 #include "openfpga_atom_netlist_utils.h"
 #include "simulation_utils.h"
+#include "fabric_global_port_info_utils.h"
 
 #include "verilog_constants.h"
 #include "verilog_writer_utils.h"
@@ -168,6 +169,82 @@ void print_verilog_random_testbench_fpga_instance(std::fstream& fp,
   fp << std::endl;
 }
 
+/********************************************************************
+ * Generate random stimulus for the reset port
+ * This function is designed to drive the reset port of a benchmark module
+ * The reset signal will be 
+ * - enabled in the 1st clock cycle
+ * - disabled in the rest of clock cycles
+ *******************************************************************/
+static 
+void print_verilog_random_testbench_reset_stimuli(std::fstream& fp,
+                                                  const AtomContext& atom_ctx,
+                                                  const VprNetlistAnnotation& netlist_annotation,
+                                                  const ModuleManager& module_manager,
+                                                  const FabricGlobalPortInfo& global_ports,
+                                                  const PinConstraints& pin_constraints,
+                                                  const std::vector<std::string>& clock_port_names,
+                                                  const BasicPort& clock_port) {
+  valid_file_stream(fp);
+
+  print_verilog_comment(fp, "----- Begin reset signal generation -----");
+
+  for (const AtomBlockId& atom_blk : atom_ctx.nlist.blocks()) {
+    /* Bypass non-input atom blocks ! */
+    if (AtomBlockType::INPAD != atom_ctx.nlist.block_type(atom_blk)) {
+      continue;
+    }
+
+    /* The block may be renamed as it contains special characters which violate Verilog syntax */
+    std::string block_name = atom_ctx.nlist.block_name(atom_blk);
+    if (true == netlist_annotation.is_block_renamed(atom_blk)) {
+      block_name = netlist_annotation.block_name(atom_blk);
+    } 
+
+    /* Bypass clock ports because their stimulus cannot be random */
+    if (clock_port_names.end() != std::find(clock_port_names.begin(), clock_port_names.end(), block_name)) {
+      continue;
+    }
+
+    /* Bypass any constained net that are mapped to a global port of the FPGA fabric
+     * because their stimulus cannot be random
+     */
+    if (false == port_is_fabric_global_reset_port(global_ports, module_manager, pin_constraints.net_pin(block_name))) { 
+      continue;
+    }
+
+    /* Generete stimuli for this net which is how reset signal works */
+    BasicPort reset_port(block_name, 1);
+    size_t initial_value = 1;
+    if (1 == global_ports.global_port_default_value(find_fabric_global_port(global_ports, module_manager,  pin_constraints.net_pin(block_name)))) {
+      initial_value = 0;
+    }
+
+    fp << "initial" << std::endl;
+    fp << "\tbegin" << std::endl;
+    fp << "\t";
+    std::vector<size_t> initial_values(reset_port.get_width(), initial_value);
+    fp << "\t";
+    fp << generate_verilog_port_constant_values(reset_port, initial_values);
+    fp << ";" << std::endl;
+
+    /* Flip the reset at the second negative edge of the clock port
+     * So the generic reset stimuli is applicable to both synchronous reset and asynchronous reset
+     * This is because the reset is activated in a complete clock cycle 
+     * This gaurantees that even for synchronous reset, the reset can be sensed in the 1st rising/falling 
+     * edge of the clock signal
+     */
+    fp << "\t@(negedge " << generate_verilog_port(VERILOG_PORT_CONKT, clock_port) << ");" << std::endl;
+    fp << "\t@(negedge " << generate_verilog_port(VERILOG_PORT_CONKT, clock_port) << ");" << std::endl;
+    print_verilog_wire_connection(fp, reset_port, reset_port, true);
+    fp << "\tend" << std::endl;
+  }
+
+  print_verilog_comment(fp, "----- End reset signal generation -----");
+
+  fp << std::endl;
+}
+
 /*********************************************************************
  * Top-level function in this file:
  * Create a Verilog testbench using random input vectors 
@@ -197,6 +274,8 @@ void print_verilog_random_top_testbench(const std::string& circuit_name,
                                         const std::string& verilog_fname,
                                         const AtomContext& atom_ctx,
                                         const VprNetlistAnnotation& netlist_annotation,
+                                        const ModuleManager& module_manager,
+                                        const FabricGlobalPortInfo& global_ports,
                                         const PinConstraints& pin_constraints,
                                         const SimulationSetting& simulation_parameters,
                                         const bool& explicit_port_mapping) {
@@ -240,8 +319,23 @@ void print_verilog_random_top_testbench(const std::string& circuit_name,
                                         pin_constraints, 
                                         simulation_parameters, 
                                         clock_ports);
+  /* TODO: use the first clock now because we do not have information how the reset is 
+   * correlated to clock ports. Once we have such information, the limitation should be removed!
+   */
+  print_verilog_random_testbench_reset_stimuli(fp, 
+                                               atom_ctx,
+                                               netlist_annotation, 
+                                               module_manager,
+                                               global_ports, 
+                                               pin_constraints, 
+                                               clock_port_names, 
+                                               clock_ports[0]);
+
   print_verilog_testbench_random_stimuli(fp, atom_ctx,
                                          netlist_annotation, 
+                                         module_manager,
+                                         global_ports, 
+                                         pin_constraints, 
                                          clock_port_names, 
                                          std::string(CHECKFLAG_PORT_POSTFIX),
                                          clock_ports);

openfpga/src/fpga_verilog/verilog_formal_random_top_testbench.h

@@ -7,6 +7,8 @@
 #include <string>
 #include "vpr_context.h"
 #include "pin_constraints.h"
+#include "module_manager.h"
+#include "fabric_global_port_info.h"
 #include "simulation_setting.h"
 
 /********************************************************************
@@ -20,6 +22,8 @@ void print_verilog_random_top_testbench(const std::string& circuit_name,
                                         const std::string& verilog_fname,
                                         const AtomContext& atom_ctx,
                                         const VprNetlistAnnotation& netlist_annotation,
+                                        const ModuleManager& module_manager,
+                                        const FabricGlobalPortInfo& global_ports,
                                         const PinConstraints& pin_constraints,
                                         const SimulationSetting& simulation_parameters,
                                         const bool& explicit_port_mapping);

openfpga/src/fpga_verilog/verilog_preconfig_top_module.cpp

@@ -135,16 +135,10 @@ int print_verilog_preconfig_top_module_connect_global_ports(std::fstream &fp,
         BasicPort module_clock_pin(module_global_port.get_name(), module_global_port.pins()[pin_id], module_global_port.pins()[pin_id]);
 
         /* If the clock port name is in the pin constraints, we should wire it to the constrained pin */
-        std::string constrained_net_name;
+        std::string constrained_net_name = pin_constraints.pin_net(module_clock_pin);
-        for (const PinConstraintId& pin_constraint : pin_constraints.pin_constraints()) {
-          if (module_clock_pin == pin_constraints.pin(pin_constraint)) {
-            constrained_net_name = pin_constraints.net(pin_constraint); 
-            break;
-          }
-        }
 
         /* If constrained to an open net or there is no clock in the benchmark, we assign it to a default value */
-        if ( (std::string(PIN_CONSTRAINT_OPEN_NET) == constrained_net_name)
+        if ( (true == pin_constraints.unmapped_net(constrained_net_name))
           || (true == benchmark_clock_port_names.empty())) {
           std::vector<size_t> default_values(1, fabric_global_ports.global_port_default_value(global_port_id));
           print_verilog_wire_constant_values(fp, module_clock_pin, default_values);
@@ -152,7 +146,7 @@ int print_verilog_preconfig_top_module_connect_global_ports(std::fstream &fp,
         }
 
         std::string clock_name_to_connect;
-        if (!constrained_net_name.empty()) {
+        if (!pin_constraints.unconstrained_net(constrained_net_name)) {
           clock_name_to_connect = constrained_net_name;
         } else {
           /* Otherwise, we must have a clear one-to-one clock net corresponding!!! */
@@ -173,8 +167,27 @@ int print_verilog_preconfig_top_module_connect_global_ports(std::fstream &fp,
     }
 
     /* For other ports, give an default value */
-    std::vector<size_t> default_values(module_global_port.get_width(), fabric_global_ports.global_port_default_value(global_port_id));
+    for (size_t pin_id = 0; pin_id < module_global_port.pins().size(); ++pin_id) {
-    print_verilog_wire_constant_values(fp, module_global_port, default_values);
+      BasicPort module_global_pin(module_global_port.get_name(),
+                                  module_global_port.pins()[pin_id],
+                                  module_global_port.pins()[pin_id]);
+
+      /* If the global port name is in the pin constraints, we should wire it to the constrained pin */
+      std::string constrained_net_name = pin_constraints.pin_net(module_global_pin);
+
+      /* - If constrained to a given net in the benchmark, we connect the global pin to the net
+       * - If constrained to an open net in the benchmark, we assign it to a default value 
+       */
+      if ( (false == pin_constraints.unconstrained_net(constrained_net_name))
+        && (false == pin_constraints.unmapped_net(constrained_net_name))) {
+        BasicPort benchmark_pin(constrained_net_name + std::string(FORMAL_VERIFICATION_TOP_MODULE_PORT_POSTFIX), 1);
+        print_verilog_wire_connection(fp, module_global_pin, benchmark_pin, false);
+      } else {
+        VTR_ASSERT_SAFE(std::string(PIN_CONSTRAINT_OPEN_NET) == constrained_net_name);
+        std::vector<size_t> default_values(module_global_pin.get_width(), fabric_global_ports.global_port_default_value(global_port_id));
+        print_verilog_wire_constant_values(fp, module_global_pin, default_values);
+      }
+    }
   }
 
   print_verilog_comment(fp, std::string("----- End Connect Global ports of FPGA top module -----"));

openfpga/src/fpga_verilog/verilog_testbench_utils.cpp

@@ -21,6 +21,7 @@
 #include "verilog_port_types.h"
 
 #include "module_manager_utils.h"
+#include "fabric_global_port_info_utils.h"
 
 #include "verilog_constants.h"
 #include "verilog_writer_utils.h"
@@ -537,6 +538,9 @@ void print_verilog_testbench_clock_stimuli(std::fstream& fp,
 void print_verilog_testbench_random_stimuli(std::fstream& fp,
                                             const AtomContext& atom_ctx,
                                             const VprNetlistAnnotation& netlist_annotation,
+                                            const ModuleManager& module_manager,
+                                            const FabricGlobalPortInfo& global_ports,
+                                            const PinConstraints& pin_constraints,
                                             const std::vector<std::string>& clock_port_names,
                                             const std::string& check_flag_port_postfix,
                                             const std::vector<BasicPort>& clock_ports) {
@@ -560,11 +564,18 @@ void print_verilog_testbench_random_stimuli(std::fstream& fp,
       block_name = netlist_annotation.block_name(atom_blk);
     } 
 
-    /* Bypass clock ports */
+    /* Bypass clock ports because their stimulus cannot be random */
     if (clock_port_names.end() != std::find(clock_port_names.begin(), clock_port_names.end(), block_name)) {
       continue;
     }
 
+    /* Bypass any constained net that are mapped to a global port of the FPGA fabric
+     * because their stimulus cannot be random
+     */
+    if (true == port_is_fabric_global_reset_port(global_ports, module_manager, pin_constraints.net_pin(block_name))) { 
+      continue;
+    }
+
     /* TODO: find the clock inputs will be initialized later */
     if (AtomBlockType::INPAD == atom_ctx.nlist.block_type(atom_blk)) {
       fp << "\t\t" << block_name << " <= 1'b0;" << std::endl;
@@ -620,11 +631,18 @@ void print_verilog_testbench_random_stimuli(std::fstream& fp,
       block_name = netlist_annotation.block_name(atom_blk);
     } 
 
-    /* Bypass clock ports */
+    /* Bypass clock ports because their stimulus cannot be random */
     if (clock_port_names.end() != std::find(clock_port_names.begin(), clock_port_names.end(), block_name)) {
       continue;
     }
 
+    /* Bypass any constained net that are mapped to a global port of the FPGA fabric
+     * because their stimulus cannot be random
+     */
+    if (true == port_is_fabric_global_reset_port(global_ports, module_manager, pin_constraints.net_pin(block_name))) { 
+      continue;
+    }
+
     /* TODO: find the clock inputs will be initialized later */
     if (AtomBlockType::INPAD == atom_ctx.nlist.block_type(atom_blk)) {
       fp << "\t\t" << block_name << " <= $random;" << std::endl;

openfpga/src/fpga_verilog/verilog_testbench_utils.h

@@ -12,6 +12,7 @@
 #include "vpr_context.h"
 #include "io_location_map.h"
 #include "vpr_netlist_annotation.h"
+#include "fabric_global_port_info.h"
 #include "pin_constraints.h"
 #include "simulation_setting.h"
 
@@ -84,6 +85,9 @@ void print_verilog_testbench_clock_stimuli(std::fstream& fp,
 void print_verilog_testbench_random_stimuli(std::fstream& fp,
                                             const AtomContext& atom_ctx,
                                             const VprNetlistAnnotation& netlist_annotation,
+                                            const ModuleManager& module_manager,
+                                            const FabricGlobalPortInfo& global_ports,
+                                            const PinConstraints& pin_constraints,
                                             const std::vector<std::string>& clock_port_names,
                                             const std::string& check_flag_port_postfix,
                                             const std::vector<BasicPort>& clock_ports);

openfpga/src/fpga_verilog/verilog_top_testbench.cpp

@@ -47,7 +47,6 @@ constexpr char* TOP_TESTBENCH_PROG_TASK_NAME = "prog_cycle_task";
 
 constexpr char* TOP_TESTBENCH_SIM_START_PORT_NAME = "sim_start";
 
-constexpr int TOP_TESTBENCH_MAGIC_NUMBER_FOR_SIMULATION_TIME = 200;
 constexpr char* TOP_TESTBENCH_ERROR_COUNTER = "nb_error";
 
 constexpr char* TOP_TB_RESET_PORT_NAME = "greset";
@@ -258,21 +257,17 @@ void print_verilog_top_testbench_config_protocol_port(std::fstream& fp,
 }
 
 /********************************************************************
- * Wire the global ports of FPGA fabric to local wires
+ * Wire the global clock ports of FPGA fabric to local wires
  *******************************************************************/
 static
-void print_verilog_top_testbench_global_ports_stimuli(std::fstream& fp,
+void print_verilog_top_testbench_global_clock_ports_stimuli(std::fstream& fp,
                                                             const ModuleManager& module_manager,
                                                             const ModuleId& top_module,
                                                             const FabricGlobalPortInfo& fabric_global_port_info,
-                                                      const SimulationSetting& simulation_parameters,
+                                                            const SimulationSetting& simulation_parameters) {
-                                                      const bool& active_global_prog_reset,
-                                                      const bool& active_global_prog_set) {
   /* Validate the file stream */
   valid_file_stream(fp);
 
-  print_verilog_comment(fp, std::string("----- Begin connecting global ports of FPGA fabric to stimuli -----"));
-
   /* Connect global clock ports to operating or programming clock signal */
   for (const FabricGlobalPortId& fabric_global_port : fabric_global_port_info.global_ports()) {
     if (false == fabric_global_port_info.global_port_is_clock(fabric_global_port)) {
@@ -317,6 +312,18 @@ void print_verilog_top_testbench_global_ports_stimuli(std::fstream& fp,
                                     1 == fabric_global_port_info.global_port_default_value(fabric_global_port));
     }
   }
+}
+
+/********************************************************************
+ * Wire the global config done ports of FPGA fabric to local wires
+ *******************************************************************/
+static
+void print_verilog_top_testbench_global_config_done_ports_stimuli(std::fstream& fp,
+                                                                  const ModuleManager& module_manager,
+                                                                  const ModuleId& top_module,
+                                                                  const FabricGlobalPortInfo& fabric_global_port_info) {
+  /* Validate the file stream */
+  valid_file_stream(fp);
 
   /* Connect global configuration done ports to configuration done signal */
   for (const FabricGlobalPortId& fabric_global_port : fabric_global_port_info.global_ports()) {
@@ -341,6 +348,20 @@ void print_verilog_top_testbench_global_ports_stimuli(std::fstream& fp,
                                   stimuli_config_done_port,
                                   1 == fabric_global_port_info.global_port_default_value(fabric_global_port));
   }
+}
+
+/********************************************************************
+ * Wire the global reset ports of FPGA fabric to local wires
+ *******************************************************************/
+static
+void print_verilog_top_testbench_global_reset_ports_stimuli(std::fstream& fp,
+                                                            const ModuleManager& module_manager,
+                                                            const ModuleId& top_module,
+                                                            const PinConstraints& pin_constraints,
+                                                            const FabricGlobalPortInfo& fabric_global_port_info,
+                                                            const bool& active_global_prog_reset) {
+  /* Validate the file stream */
+  valid_file_stream(fp);
 
   /* Connect global reset ports to operating or programming reset signal */
   for (const FabricGlobalPortId& fabric_global_port : fabric_global_port_info.global_ports()) {
@@ -373,20 +394,58 @@ void print_verilog_top_testbench_global_ports_stimuli(std::fstream& fp,
       stimuli_reset_port.set_name(std::string(TOP_TB_RESET_PORT_NAME));
       stimuli_reset_port.set_width(1);
     }
+
+    BasicPort module_global_port_info = module_manager.module_port(top_module, module_global_port);
+
+    for (size_t pin_id = 0; pin_id < module_global_port_info.pins().size(); ++pin_id) {
+      BasicPort module_global_pin(module_global_port_info.get_name(),
+                                  module_global_port_info.pins()[pin_id],
+                                  module_global_port_info.pins()[pin_id]);
+
+      /* Regular reset port can be mapped by a net from user design */
+      if (false == fabric_global_port_info.global_port_is_prog(fabric_global_port)) {
+        /* If the global port name is in the pin constraints, we should wire it to the constrained pin */
+        std::string constrained_net_name = pin_constraints.pin_net(module_global_pin);
+
+        /* - If constrained to a given net in the benchmark, we connect the global pin to the net */
+        if ( (false == pin_constraints.unconstrained_net(constrained_net_name))
+          && (false == pin_constraints.unmapped_net(constrained_net_name))) {
+          BasicPort benchmark_pin(constrained_net_name, 1);
+          print_verilog_wire_connection(fp, module_global_pin,
+                                        benchmark_pin,
+                                        false);
+          continue; /* Finish the net assignment for this reset pin */
+        }
+      }
+      
       /* Wire the port to the input stimuli:
        * The wiring will be inverted if the default value of the global port is 1
        * Otherwise, the wiring will not be inverted!
        */
       if (true == activate) {
-      print_verilog_wire_connection(fp, module_manager.module_port(top_module, module_global_port),
+        print_verilog_wire_connection(fp, module_global_pin,
                                       stimuli_reset_port,
                                       1 == fabric_global_port_info.global_port_default_value(fabric_global_port));
       } else {
         VTR_ASSERT_SAFE(false == activate);
-      print_verilog_wire_constant_values(fp, module_manager.module_port(top_module, module_global_port),
+        print_verilog_wire_constant_values(fp, module_global_pin,
                                            std::vector<size_t>(1, fabric_global_port_info.global_port_default_value(fabric_global_port)));
       }
     }
+  }
+}
+
+/********************************************************************
+ * Wire the global set ports of FPGA fabric to local wires
+ *******************************************************************/
+static
+void print_verilog_top_testbench_global_set_ports_stimuli(std::fstream& fp,
+                                                          const ModuleManager& module_manager,
+                                                          const ModuleId& top_module,
+                                                          const FabricGlobalPortInfo& fabric_global_port_info,
+                                                          const bool& active_global_prog_set) {
+  /* Validate the file stream */
+  valid_file_stream(fp);
 
   /* Connect global set ports to operating or programming set signal */
   for (const FabricGlobalPortId& fabric_global_port : fabric_global_port_info.global_ports()) {
@@ -438,6 +497,18 @@ void print_verilog_top_testbench_global_ports_stimuli(std::fstream& fp,
                                          std::vector<size_t>(1, fabric_global_port_info.global_port_default_value(fabric_global_port)));
     }
   }
+}
+
+/********************************************************************
+ * Wire the regular global ports of FPGA fabric to local wires
+ *******************************************************************/
+static
+void print_verilog_top_testbench_regular_global_ports_stimuli(std::fstream& fp,
+                                                              const ModuleManager& module_manager,
+                                                              const ModuleId& top_module,
+                                                              const FabricGlobalPortInfo& fabric_global_port_info) {
+  /* Validate the file stream */
+  valid_file_stream(fp);
 
   /* For the rest of global ports, wire them to constant signals */
   for (const FabricGlobalPortId& fabric_global_port : fabric_global_port_info.global_ports()) {
@@ -478,6 +549,55 @@ void print_verilog_top_testbench_global_ports_stimuli(std::fstream& fp,
     std::vector<size_t> default_values(module_port.get_width(), fabric_global_port_info.global_port_default_value(fabric_global_port));
     print_verilog_wire_constant_values(fp, module_port, default_values);
   }
+}
+
+/********************************************************************
+ * Wire the global ports of FPGA fabric to local wires
+ *******************************************************************/
+static
+void print_verilog_top_testbench_global_ports_stimuli(std::fstream& fp,
+                                                      const ModuleManager& module_manager,
+                                                      const ModuleId& top_module,
+                                                      const PinConstraints& pin_constraints,
+                                                      const FabricGlobalPortInfo& fabric_global_port_info,
+                                                      const SimulationSetting& simulation_parameters,
+                                                      const bool& active_global_prog_reset,
+                                                      const bool& active_global_prog_set) {
+  /* Validate the file stream */
+  valid_file_stream(fp);
+
+  print_verilog_comment(fp, std::string("----- Begin connecting global ports of FPGA fabric to stimuli -----"));
+
+  print_verilog_top_testbench_global_clock_ports_stimuli(fp,
+                                                         module_manager,
+                                                         top_module,
+                                                         fabric_global_port_info,
+                                                         simulation_parameters);
+
+  print_verilog_top_testbench_global_config_done_ports_stimuli(fp,
+                                                               module_manager,
+                                                               top_module,
+                                                               fabric_global_port_info);
+
+
+  print_verilog_top_testbench_global_reset_ports_stimuli(fp,
+                                                         module_manager,
+                                                         top_module,
+                                                         pin_constraints,
+                                                         fabric_global_port_info,
+                                                         active_global_prog_reset);
+
+  print_verilog_top_testbench_global_set_ports_stimuli(fp,
+                                                       module_manager,
+                                                       top_module,
+                                                       fabric_global_port_info,
+                                                       active_global_prog_set);
+
+
+  print_verilog_top_testbench_regular_global_ports_stimuli(fp,
+                                                           module_manager,
+                                                           top_module,
+                                                           fabric_global_port_info);
 
   print_verilog_comment(fp, std::string("----- End connecting global ports of FPGA fabric to stimuli -----"));
 }
@@ -1810,6 +1930,54 @@ void print_verilog_top_testbench_bitstream(std::fstream& fp,
   }
 }
 
+/********************************************************************
+ * Connect proper stimuli to the reset port
+ * This function is designed to drive the reset port of a benchmark module
+ *******************************************************************/
+static 
+void print_verilog_top_testbench_reset_stimuli(std::fstream& fp,
+                                               const AtomContext& atom_ctx,
+                                               const VprNetlistAnnotation& netlist_annotation,
+                                               const ModuleManager& module_manager,
+                                               const FabricGlobalPortInfo& global_ports,
+                                               const PinConstraints& pin_constraints,
+                                               const std::vector<std::string>& clock_port_names) {
+  valid_file_stream(fp);
+
+  print_verilog_comment(fp, "----- Begin reset signal generation -----");
+
+  for (const AtomBlockId& atom_blk : atom_ctx.nlist.blocks()) {
+    /* Bypass non-input atom blocks ! */
+    if (AtomBlockType::INPAD != atom_ctx.nlist.block_type(atom_blk)) {
+      continue;
+    }
+
+    /* The block may be renamed as it contains special characters which violate Verilog syntax */
+    std::string block_name = atom_ctx.nlist.block_name(atom_blk);
+    if (true == netlist_annotation.is_block_renamed(atom_blk)) {
+      block_name = netlist_annotation.block_name(atom_blk);
+    } 
+
+    /* Bypass clock ports because their stimulus cannot be random */
+    if (clock_port_names.end() != std::find(clock_port_names.begin(), clock_port_names.end(), block_name)) {
+      continue;
+    }
+
+    /* Bypass any constained net that are mapped to a global port of the FPGA fabric
+     * because their stimulus cannot be random
+     */
+    if (false == port_is_fabric_global_reset_port(global_ports, module_manager, pin_constraints.net_pin(block_name))) { 
+      continue;
+    }
+
+    /* Connect stimuli to greset with an optional inversion, depending on the default value */
+    BasicPort reset_port(block_name, 1);
+    print_verilog_wire_connection(fp, reset_port,
+                                  BasicPort(TOP_TB_RESET_PORT_NAME, 1),
+                                  1 == global_ports.global_port_default_value(find_fabric_global_port(global_ports, module_manager, pin_constraints.net_pin(block_name))));
+  }
+}
+
 /********************************************************************
  * Add auto-check codes for the full testbench
  * in particular for the configuration phase:
@@ -1994,6 +2162,7 @@ void print_verilog_top_testbench(const ModuleManager& module_manager,
   /* Generate stimuli for global ports or connect them to existed signals */
   print_verilog_top_testbench_global_ports_stimuli(fp,
                                                    module_manager, top_module,
+                                                   pin_constraints,
                                                    global_ports,
                                                    simulation_parameters,
                                                    active_global_prog_reset,
@@ -2042,9 +2211,20 @@ void print_verilog_top_testbench(const ModuleManager& module_manager,
                                                   top_module);
   }
 
+
   /* Add stimuli for reset, set, clock and iopad signals */
+  print_verilog_top_testbench_reset_stimuli(fp, 
+                                            atom_ctx,
+                                            netlist_annotation, 
+                                            module_manager,
+                                            global_ports, 
+                                            pin_constraints, 
+                                            clock_port_names);
   print_verilog_testbench_random_stimuli(fp, atom_ctx,
                                          netlist_annotation,
+                                         module_manager,
+                                         global_ports,
+                                         pin_constraints,
                                          clock_port_names,
                                          std::string(TOP_TESTBENCH_CHECKFLAG_PORT_POSTFIX),
                                          std::vector<BasicPort>(1, BasicPort(std::string(TOP_TB_OP_CLOCK_PORT_NAME), 1)));

openfpga/src/utils/fabric_global_port_info_utils.cpp

@@ -11,6 +11,8 @@
 #include "vtr_assert.h"
 #include "vtr_log.h"
 
+#include "openfpga_naming.h"
+
 #include "fabric_global_port_info_utils.h"
 
 /* begin namespace openfpga */
@@ -58,4 +60,51 @@ std::vector<FabricGlobalPortId> find_fabric_global_programming_set_ports(const F
   return global_prog_set_ports;
 }
 
+/********************************************************************
+ * Identify if a port is in the list of fabric global port
+ * and its functionality is a reset port which is not used for programming FPGAs
+ *******************************************************************/
+bool port_is_fabric_global_reset_port(const FabricGlobalPortInfo& fabric_global_port_info,
+                                      const ModuleManager& module_manager,
+                                      const BasicPort& port) {
+  /* Find the top_module: the fabric global ports are always part of the ports of the top module */
+  ModuleId top_module = module_manager.find_module(generate_fpga_top_module_name());
+  VTR_ASSERT(true == module_manager.valid_module_id(top_module));
+
+  for (const FabricGlobalPortId& fabric_global_port_id : fabric_global_port_info.global_ports()) {
+    if ( (false == fabric_global_port_info.global_port_is_reset(fabric_global_port_id))
+      || (true == fabric_global_port_info.global_port_is_prog(fabric_global_port_id))) {
+      continue;
+    }
+
+    BasicPort module_global_port = module_manager.module_port(top_module, fabric_global_port_info.global_module_port(fabric_global_port_id));
+    if ( (true == module_global_port.mergeable(port))
+      && (true == module_global_port.contained(port)) ) {
+      return true;
+    }
+  }
+
+  return false;
+}
+
+/********************************************************************
+ * Find a global port with a given name
+ *******************************************************************/
+FabricGlobalPortId find_fabric_global_port(const FabricGlobalPortInfo& fabric_global_port_info,
+                                           const ModuleManager& module_manager,
+                                           const BasicPort& port) {
+  /* Find the top_module: the fabric global ports are always part of the ports of the top module */
+  ModuleId top_module = module_manager.find_module(generate_fpga_top_module_name());
+  VTR_ASSERT(true == module_manager.valid_module_id(top_module));
+
+  for (const FabricGlobalPortId& fabric_global_port_id : fabric_global_port_info.global_ports()) {
+    BasicPort module_global_port = module_manager.module_port(top_module, fabric_global_port_info.global_module_port(fabric_global_port_id));
+    if ( (true == module_global_port.mergeable(port))
+      && (true == module_global_port.contained(port)) ) {
+      return fabric_global_port_id;
+    }
+  }
+  return FabricGlobalPortId::INVALID();
+}
+
 } /* end namespace openfpga */

openfpga/src/utils/fabric_global_port_info_utils.h

@@ -6,6 +6,7 @@
  *******************************************************************/
 #include <vector>
 #include "fabric_global_port_info.h"
+#include "module_manager.h"
 
 /********************************************************************
  * Function declaration
@@ -18,6 +19,14 @@ std::vector<FabricGlobalPortId> find_fabric_global_programming_reset_ports(const
 
 std::vector<FabricGlobalPortId> find_fabric_global_programming_set_ports(const FabricGlobalPortInfo& fabric_global_port_info);
 
+bool port_is_fabric_global_reset_port(const FabricGlobalPortInfo& fabric_global_port_info,
+                                      const ModuleManager& module_manager,
+                                      const BasicPort& port);
+
+FabricGlobalPortId find_fabric_global_port(const FabricGlobalPortInfo& fabric_global_port_info,
+                                           const ModuleManager& module_manager,
+                                           const BasicPort& port);
+
 } /* end namespace openfpga */
 
 #endif

openfpga_flow/openfpga_shell_scripts/example_without_ace_script.openfpga

@@ -55,7 +55,7 @@ write_fabric_verilog --file ./SRC --explicit_port_mapping --include_timing --pri
 #  - Enable top-level testbench which is a full verification including programming circuit and core logic of FPGA
 #  - Enable pre-configured top-level testbench which is a fast verification skipping programming phase
 #  - Simulation ini file is optional and is needed only when you need to interface different HDL simulators using openfpga flow-run scripts
-write_verilog_testbench --file ./SRC --reference_benchmark_file_path ${REFERENCE_VERILOG_TESTBENCH} --print_top_testbench --print_preconfig_top_testbench --print_simulation_ini ./SimulationDeck/simulation_deck.ini --include_signal_init --support_icarus_simulator 
+write_verilog_testbench --file ./SRC --reference_benchmark_file_path ${REFERENCE_VERILOG_TESTBENCH} --print_top_testbench --print_preconfig_top_testbench --print_simulation_ini ./SimulationDeck/simulation_deck.ini --include_signal_init --support_icarus_simulator --pin_constraints_file ${OPENFPGA_PIN_CONSTRAINTS_FILE}
 
 # Write the SDC files for PnR backend
 #  - Turn on every options here

openfpga_flow/tasks/basic_tests/k4_series/k4n4_fracff/config/pin_constraints.xml

@@ -0,0 +1,7 @@
+<pin_constraints>
+  <!-- For a given .blif file, we want to assign 
+       - the reset signal to the op_reset[0] port of the FPGA fabric
+    -->
+  <set_io pin="op_reset[0]" net="reset"/>
+</pin_constraints>
+

openfpga_flow/tasks/basic_tests/k4_series/k4n4_fracff/config/task.conf

@@ -19,6 +19,7 @@ fpga_flow=yosys_vpr
 openfpga_shell_template=${PATH:OPENFPGA_PATH}/openfpga_flow/openfpga_shell_scripts/example_without_ace_script.openfpga
 openfpga_arch_file=${PATH:OPENFPGA_PATH}/openfpga_flow/openfpga_arch/k4_frac_N4_fracff_40nm_cc_openfpga.xml
 openfpga_sim_setting_file=${PATH:OPENFPGA_PATH}/openfpga_flow/openfpga_simulation_settings/fixed_sim_openfpga.xml
+openfpga_pin_constraints_file=${PATH:OPENFPGA_PATH}/openfpga_flow/tasks/basic_tests/k4_series/k4n4_fracff/config/pin_constraints.xml
 # Yosys script parameters
 yosys_cell_sim_verilog=${PATH:OPENFPGA_PATH}/openfpga_flow/openfpga_yosys_techlib/openfpga_dff_sim.v
 yosys_dff_map_verilog=${PATH:OPENFPGA_PATH}/openfpga_flow/openfpga_yosys_techlib/openfpga_dff_map.v