Build optimizations

Coauthor: Antigravity

Makefile

@@ -2,6 +2,13 @@
 LOG_REDIR = >&
 TIME=/usr/bin/time --format "Elapsed: %E, Memory: %M KB [Swaps %W]"
 
+# Enable ccache for Verilator compilation
+export OBJCACHE = ccache
+export CXX = clang++
+export CC = clang
+export OPT_FAST = -O1
+export OPT_SLOW = -O0
+
 # Makefile variables
 # Use as many threads as possible while keeping 2 for IO, browsing, etc.
 # USE_PROCS = $(( $(shell nproc --all) - 2 ))
@@ -82,7 +89,7 @@ prepare_area:
 	@if [ ! -d $(PROJ_BASE)/logs ]; then mkdir -p $(PROJ_BASE)/logs; fi
 
 #
-# C code generation from SystemVerilog
+# C code generation from SystemVerilog (optional translation/lint)
 #
 build_sv: prepare_area $(SV_OUT)
 
@@ -98,9 +105,9 @@ $(SV_OUT): $(PROJ_BASE)/logs $(SV_DEPS)
 #
 # C code build to generate testbench executable
 #
-build_cpp: build_sv $(CPP_OUT)
+build_cpp: prepare_area $(CPP_OUT)
 
-$(CPP_OUT): $(SV_OUT)
+$(CPP_OUT): $(SV_DEPS)
 	$(info #-------------------------)
 	$(info # Building CPP ($(USE_PROCS) threads))
 	$(info #-------------------------)

src/axi/axi_agent.sv

@@ -102,10 +102,10 @@ class axi_agent extends uvm_agent;
 
     // --------------------------------------------------
     // Run phase
-    virtual function void run_phase(uvm_phase phase);
+    virtual task run_phase(uvm_phase phase);
         `uvm_info("axi_agent", $sformatf("Running AXI agent: %s as %s",
             get_full_name(), agent_type.name()), UVM_LOW)
-    endfunction
+    endtask
 endclass : axi_agent
 
 // ----------------------------------------------------------------------

src/axi/axi_agent_config.sv

@@ -12,6 +12,30 @@ class axi_agent_config extends uvm_object;
     /// Maximum value of pre_response_delay
     int pre_response_delay_max = 20;
 
+    // --------------------------------------------------
+    // Functional coverage
+    // Cover the *actual* delays produced by the getters.
+    // --------------------------------------------------
+    /* verilator lint_off COVERIGN */
+    covergroup cg_pre_transaction_delay with function sample(int dly);
+        option.per_instance = 1;
+        cp_dly: coverpoint dly {
+            bins min = {pre_transaction_delay_min};
+            bins max = {pre_transaction_delay_max};
+            bins in_range[] = {[pre_transaction_delay_min:pre_transaction_delay_max]};
+        }
+    endgroup
+
+    covergroup cg_pre_response_delay with function sample(int dly);
+        option.per_instance = 1;
+        cp_dly: coverpoint dly {
+            bins min = {pre_response_delay_min};
+            bins max = {pre_response_delay_max};
+            bins in_range[] = {[pre_response_delay_min:pre_response_delay_max]};
+        }
+    endgroup
+    /* verilator lint_on COVERIGN */
+
     `uvm_object_utils_begin(axi_agent_config)
         `uvm_field_int(pre_transaction_delay_min, UVM_DEFAULT)
         `uvm_field_int(pre_transaction_delay_max, UVM_DEFAULT)
@@ -22,6 +46,8 @@ class axi_agent_config extends uvm_object;
     // --------------------------------------------------
     function new(string name = "axi_agent_config");
         super.new(name);
+        cg_pre_transaction_delay = new();
+        cg_pre_response_delay = new();
     endfunction
 
     // --------------------------------------------------
@@ -45,6 +71,7 @@ class axi_agent_config extends uvm_object;
         //     `uvm_error("get_pre_transaction_delay", "Randomization failed")
         // end
         dly = $urandom_range(pre_transaction_delay_max, pre_transaction_delay_min);
+        cg_pre_transaction_delay.sample(dly);
         return dly;
     endfunction
 
@@ -62,6 +89,7 @@ class axi_agent_config extends uvm_object;
         //     `uvm_error("get_pre_response_delay", "Randomization failed")
         // end
         dly = $urandom_range(pre_response_delay_max, pre_response_delay_min);
+        cg_pre_response_delay.sample(dly);
         return dly;
     endfunction
 endclass

src/axi/axi_driver.sv

@@ -47,7 +47,7 @@ class axi_driver extends uvm_driver; // #(axi_transaction);
 
     // --------------------------------------------------
     // Run phase
-    virtual function void run_phase(uvm_phase phase);
+    virtual task run_phase(uvm_phase phase);
         // Open transaction log file
         trk_file = $fopen($sformatf("axi_driver.%s.log", agent_type.name()), "w");
         if (trk_file == 0) begin
@@ -58,7 +58,7 @@ class axi_driver extends uvm_driver; // #(axi_transaction);
 
         // Start driver
         drive_axi(phase);
-    endfunction
+    endtask
 
     // --------------------------------------------------
     virtual task drive_axi(uvm_phase phase);

src/axi/axi_monitor.sv

@@ -44,7 +44,7 @@ class axi_monitor extends uvm_monitor; // #(axi_transaction);
 
     // --------------------------------------------------
     // Run phase
-    virtual function void run_phase(uvm_phase phase);
+    virtual task run_phase(uvm_phase phase);
         // Open transaction log file
         trk_file = $fopen($sformatf("axi_transactions.%s.log", agent_type.name()), "w");
         if (trk_file == 0) begin
@@ -55,7 +55,7 @@ class axi_monitor extends uvm_monitor; // #(axi_transaction);
 
         // Start monitoring
         do_monitor();
-    endfunction
+    endtask
 
     // --------------------------------------------------
     // Monitor logic to capture transactions
@@ -93,6 +93,7 @@ class axi_monitor extends uvm_monitor; // #(axi_transaction);
                     txn.txn_type = AXI_WRITE;
                     txn.addr = mon_if.AWADDR;
                     txn.length = mon_if.AWLEN;
+                    txn.size = mon_if.AWSIZE;
                 end
             end
 
@@ -112,11 +113,12 @@ class axi_monitor extends uvm_monitor; // #(axi_transaction);
             if (txn_ph == 2) begin
                 if (((mon_if.BREADY != prev_bready) || (mon_if.BVALID != prev_bvalid))
                     && ((mon_if.BREADY === 1'b1) && (mon_if.BVALID === 1'b1))) begin
-                    txn_ph = 2; // DATA
+                    txn_ph = 0; // IDLE
 
                     // Capture transaction details here
-                    txn.resp = mon_if.WSTRB;
+                    txn.resp = mon_if.BRESP;
 
+                    txn.sample_coverage();
                     ap.write(txn);
                     write_transaction_to_file(txn);
                 end
@@ -155,6 +157,7 @@ class axi_monitor extends uvm_monitor; // #(axi_transaction);
                     txn.txn_type = AXI_READ;
                     txn.addr = mon_if.ARADDR;
                     txn.length = mon_if.ARLEN;
+                    txn.size = mon_if.ARSIZE;
                 end
             end
 
@@ -166,27 +169,14 @@ class axi_monitor extends uvm_monitor; // #(axi_transaction);
 
                     // Capture transaction details here
                     txn.data = mon_if.RDATA;
+                    txn.resp = mon_if.RRESP;
 
+                    txn.sample_coverage();
                     ap.write(txn);
                     write_transaction_to_file(txn);
                 end
             end
 
-            if (((mon_if.ARREADY != prev_arready) || (mon_if.ARVALID != prev_arvalid))
-                && ((mon_if.ARREADY === 1'b1) && (mon_if.ARVALID === 1'b1))) begin
-                axi_transaction txn;
-
-                txn = axi_transaction::type_id::create("txn");
-
-                // Capture transaction details here
-                txn.txn_type = AXI_READ;
-                txn.addr = mon_if.ARADDR;
-                txn.length = mon_if.ARLEN;
-
-                ap.write(txn);
-                write_transaction_to_file(txn);
-            end
-
             // Update previous values
             prev_arready = mon_if.ARREADY;
             prev_arvalid = mon_if.ARVALID;

src/axi/axi_transaction.sv

@@ -9,6 +9,48 @@ class axi_transaction extends uvm_sequence_item;
     rand bit [2:0]                      size; // Size
     rand bit [7:0]                      length; // Length
 
+    // --------------------------------------------------
+    // Functional coverage
+    // --------------------------------------------------
+    /* verilator lint_off COVERIGN */
+    covergroup cg_axi_transaction with function sample();
+        option.per_instance = 1;
+
+        cp_type:   coverpoint txn_type;
+        cp_size:   coverpoint size {
+            bins b0 = {3'd0};
+            bins b1 = {3'd1};
+            bins b2 = {3'd2};
+            bins b3 = {3'd3};
+            bins b4 = {3'd4};
+            bins b5 = {3'd5};
+            bins b6 = {3'd6};
+            bins b7 = {3'd7};
+        }
+        cp_len:    coverpoint length {
+            bins single = {8'd0};
+            bins short  = {[8'd1:8'd3]};
+            bins mid    = {[8'd4:8'd15]};
+            bins long   = {[8'd16:8'd255]};
+        }
+        cp_resp:   coverpoint resp;
+        cp_strb:   coverpoint strb {
+            bins none = {'0};
+            bins full = { {`DATA_WIDTH_DIV_8{1'b1}} };
+            bins other = default;
+        }
+        cp_addr_lsb: coverpoint addr[11:0] {
+            bins aligned = {12'h000};
+            bins unaligned = default;
+        }
+        cp_addr_msb: coverpoint addr[`ADDR_WIDTH-1 -: 4] iff (`ADDR_WIDTH >= 4);
+
+        x_type_size: cross cp_type, cp_size;
+        x_type_len:  cross cp_type, cp_len;
+        x_type_resp: cross cp_type, cp_resp;
+    endgroup
+    /* verilator lint_on COVERIGN */
+
     `uvm_object_utils_begin(axi_transaction)
         `uvm_field_enum(axi_transaction_type_t, txn_type, UVM_DEFAULT)
         `uvm_field_int(addr, UVM_DEFAULT)
@@ -22,6 +64,11 @@ class axi_transaction extends uvm_sequence_item;
     // Constructor
     function new(string name = "axi_transaction");
         super.new(name);
+        cg_axi_transaction = new();
+    endfunction
+
+    function void sample_coverage();
+        cg_axi_transaction.sample();
     endfunction
 
     // Get transaction id - made up of sequence ID and trasacton ID