Random seed set to 2 for now

Makefile

@@ -45,6 +45,7 @@ BUILD_ARGS=-I$(UVM_HOME)/src -I. \
         --error-limit 10 \
         --timing $(TIMESCALE) \
         --trace \
+        --x-initial 0 \
         --top tb_top \
         +define+SVA_ON \
         $(TB_DEFINES) \
@@ -112,7 +113,7 @@ run: $(CPP_OUT)
 	$(info #---------------------)
 	@if [ ! -d runs/$(TEST_NAME) ]; then mkdir -p runs/$(TEST_NAME); fi
 	@cd runs/$(TEST_NAME) && \
-        $(PROJ_BASE)/obj_dir/$(PROJ).sim +UVM_TESTNAME=$(TEST_NAME) +UVM_CONFIG_DB_TRACE |& tee $(SIM_LOG)
+        $(PROJ_BASE)/obj_dir/$(PROJ).sim +verilator+seed+2 +UVM_TESTNAME=$(TEST_NAME) +UVM_CONFIG_DB_TRACE |& tee $(SIM_LOG)
 	notify-send "[$(PROJ)] Test run done"
 
 #

axi.gtkw

@@ -1,20 +1,21 @@
 [*]
-[*] GTKWave Analyzer v3.3.124 (w)1999-2025 BSI
-[*] Sun Aug 24 18:22:14 2025
+[*] GTKWave Analyzer v3.3.125 (w)1999-2025 BSI
+[*] Sun Sep 28 00:35:45 2025
 [*]
 [dumpfile] "/home/mahesh/dev/sv/axipg/runs/test_basic/wave.vcd"
-[dumpfile_mtime] "Sun Aug 24 18:18:15 2025"
-[dumpfile_size] 19493
+[dumpfile_mtime] "Sun Sep 28 00:13:17 2025"
+[dumpfile_size] 48138
 [savefile] "/home/mahesh/dev/sv/axipg/axi.gtkw"
 [timestart] 0
-[size] 1388 1348
-[pos] -1 -1
-*-6.502242 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1
+[size] 1900 988
+[pos] -7 -4
+*-10.447897 1195 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1 -1
 [treeopen] tb_top.
+[treeopen] tb_top.t_if.
 [sst_width] 290
-[signals_width] 126
+[signals_width] 150
 [sst_expanded] 1
-[sst_vpaned_height] 417
+[sst_vpaned_height] 292
 @28
 tb_top.t_if.ARESETn
 tb_top.t_if.ACLK
@@ -26,6 +27,17 @@ tb_top.t_if.ARLEN[7:0]
 @200
 -
 @28
+tb_top.t_if.RVALID
+@29
+tb_top.t_if.RREADY
+@22
+tb_top.t_if.RDATA[63:0]
+@28
+tb_top.t_if.RLAST
+tb_top.t_if.RRESP[0]
+@200
+-
+@28
 tb_top.t_if.AWVALID
 tb_top.t_if.AWREADY
 @22
@@ -43,5 +55,9 @@ tb_top.t_if.WDATA[63:0]
 tb_top.t_if.WLAST
 @200
 -
+@28
+tb_top.t_if.BVALID
+tb_top.t_if.BREADY
+tb_top.t_if.BRESP[0]
 [pattern_trace] 1
 [pattern_trace] 0

common/axi.intf.sv

@@ -85,6 +85,7 @@ interface axi_intf #(
     // A2.1.1 Write request channel
     logic                                           WVALID;            // Valid indicator [Manager]
     logic                                           WREADY;            // Ready indicator [Subordinate]
+    logic                          [ID_W_WIDTH-1:0] WID;               // Transaction identifier for the write channels [Manager]
     logic                          [DATA_WIDTH-1:0] WDATA;             // Write data [Manager]
     logic                    [DATA_WIDTH_DIV_8-1:0] WSTRB;             // Write data strobes [Manager]
     logic       [CEIL_DATA_WIDTH_DIV_128_TMS_4-1:0] WTAG;              // Memory Tag [Manager]
@@ -210,6 +211,7 @@ interface axi_intf #(
         // A2.1.1 Write request channel
         output   WVALID,
         input    WREADY,
+        output   WID,
         output   WDATA,
         output   WSTRB,
         output   WTAG,
@@ -336,6 +338,7 @@ interface axi_intf #(
         // A2.1.1 Write request channel
         input    WVALID,
         output   WREADY,
+        input    WID,
         input    WDATA,
         input    WSTRB,
         input    WTAG,

scripts/gen_axi_intf.pl

@@ -248,44 +248,44 @@ sub get_axi_intf_data {
                 'name' => 'A2.1.1 Write request channel',
                 'signals' => [
                     # n: name, w: width, s: source, d: description
-                    {'n' =>'AWVALID','w' =>'1','s' =>'Manager','d' =>'Valid indicator' },
-                    {'n' =>'AWREADY','w' =>'1','s' =>'Subordinate','d' =>'Ready indicator' },
-                    {'n' =>'AWID','w' =>'ID_W_WIDTH','s' =>'Manager','d' =>'Transaction identifier for the write channels' },
-                    {'n' =>'AWADDR','w' =>'ADDR_WIDTH','s' =>'Manager','d' =>'Transaction address' },
-                    {'n' =>'AWREGION','w' =>'4','s' =>'Manager','d' =>'Region identifier' },
-                    {'n' =>'AWLEN','w' =>'8','s' =>'Manager','d' =>'Transaction length' },
-                    {'n' =>'AWSIZE','w' =>'3','s' =>'Manager','d' =>'Transaction size' },
-                    {'n' =>'AWBURST','w' =>'2','s' =>'Manager','d' =>'Burst attribute' },
-                    {'n' =>'AWLOCK','w' =>'1','s' =>'Manager','d' =>'Exclusive access indicator' },
-                    {'n' =>'AWCACHE','w' =>'4','s' =>'Manager','d' =>'Memory attributes' },
-                    {'n' =>'AWPROT','w' =>'3','s' =>'Manager','d' =>'Access attributes' },
-                    {'n' =>'AWNSE','w' =>'1','s' =>'Manager','d' =>'Non-secure extension bit for RME' },
-                    {'n' =>'AWQOS','w' =>'4','s' =>'Manager','d' =>'QoS identifier' },
-                    {'n' =>'AWUSER','w' =>'USER_REQ_WIDTH','s' =>'Manager','d' =>'User-defined extension to a request' },
-                    {'n' =>'AWDOMAIN','w' =>'2','s' =>'Manager','d' =>'Shareability domain of a request' },
-                    {'n' =>'AWSNOOP','w' =>'AWSNOOP_WIDTH','s' =>'Manager','d' =>'Write request opcode' },
-                    {'n' =>'AWSTASHNID','w' =>'11','s' =>'Manager','d' =>'Stash Node ID' },
-                    {'n' =>'AWSTASHNIDEN','w' =>'1','s' =>'Manager','d' =>'Stash Node ID enable' },
-                    {'n' =>'AWSTASHLPID','w' =>'5','s' =>'Manager','d' =>'Stash Logical Processor ID' },
-                    {'n' =>'AWSTASHLPIDEN','w' =>'1','s' =>'Manager','d' =>'Stash Logical Processor ID enable' },
-                    {'n' =>'AWTRACE','w' =>'1','s' =>'Manager','d' =>'Trace signal' },
-                    {'n' =>'AWLOOP','w' =>'LOOP_W_WIDTH','s' =>'Manager','d' =>'Loopback signals on the write channels' },
-                    {'n' =>'AWMMUVALID','w' =>'1','s' =>'Manager','d' =>'MMU signal qualifier' },
-                    {'n' =>'AWMMUSECSID','w' =>'SECSID_WIDTH','s' =>'Manager','d' =>'Secure Stream ID' },
-                    {'n' =>'AWMMUSID','w' =>'SID_WIDTH','s' =>'Manager','d' =>'StreamID' },
-                    {'n' =>'AWMMUSSIDV','w' =>'1','s' =>'Manager','d' =>'SubstreamID valid' },
-                    {'n' =>'AWMMUSSID','w' =>'SSID_WIDTH','s' =>'Manager','d' =>'SubstreamID' },
-                    {'n' =>'AWMMUATST','w' =>'1','s' =>'Manager','d' =>'Address translated indicator' },
-                    {'n' =>'AWMMUFLOW','w' =>'2','s' =>'Manager','d' =>'SMMU flow type' },
-                    {'n' =>'AWPBHA','w' =>'4','s' =>'Manager','d' =>'Page-based Hardware Attributes' },
-                    {'n' =>'AWNSAID','w' =>'4','s' =>'Manager','d' =>'Non-secure Access ID' },
-                    {'n' =>'AWSUBSYSID','w' =>'SUBSYSID_WIDTH','s' =>'Manager','d' =>'Subsystem ID' },
-                    {'n' =>'AWATOP','w' =>'6','s' =>'Manager','d' =>'Atomic transaction opcode' },
-                    {'n' =>'AWMPAM','w' =>'MPAM_WIDTH','s' =>'Manager','d' =>'MPAM information with a request' },
-                    {'n' =>'AWIDUNQ','w' =>'1','s' =>'Manager','d' =>'Unique ID indicator' },
-                    {'n' =>'AWCMO','w' =>'AWCMO_WIDTH','s' =>'Manager','d' =>'CMO type' },
-                    {'n' =>'AWTAGOP','w' =>'2','s' =>'Manager','d' =>'Memory Tag operation for write requests' },
-                    {'n' =>'AWMECID','w' =>'MECID_WIDTH','s' =>'Manager','d' =>'Memory Encryption Context identifier' },
+                    { 'n' => 'AWVALID','w' => '1','s' => 'Manager','d' => 'Valid indicator' },
+                    { 'n' => 'AWREADY','w' => '1','s' => 'Subordinate','d' => 'Ready indicator' },
+                    { 'n' => 'AWID','w' => 'ID_W_WIDTH','s' => 'Manager','d' => 'Transaction identifier for the write channels' },
+                    { 'n' => 'AWADDR','w' => 'ADDR_WIDTH','s' => 'Manager','d' => 'Transaction address' },
+                    { 'n' => 'AWREGION','w' => '4','s' => 'Manager','d' => 'Region identifier' },
+                    { 'n' => 'AWLEN','w' => '8','s' => 'Manager','d' => 'Transaction length' },
+                    { 'n' => 'AWSIZE','w' => '3','s' => 'Manager','d' => 'Transaction size' },
+                    { 'n' => 'AWBURST','w' => '2','s' => 'Manager','d' => 'Burst attribute' },
+                    { 'n' => 'AWLOCK','w' => '1','s' => 'Manager','d' => 'Exclusive access indicator' },
+                    { 'n' => 'AWCACHE','w' => '4','s' => 'Manager','d' => 'Memory attributes' },
+                    { 'n' => 'AWPROT','w' => '3','s' => 'Manager','d' => 'Access attributes' },
+                    { 'n' => 'AWNSE','w' => '1','s' => 'Manager','d' => 'Non-secure extension bit for RME' },
+                    { 'n' => 'AWQOS','w' => '4','s' => 'Manager','d' => 'QoS identifier' },
+                    { 'n' => 'AWUSER','w' => 'USER_REQ_WIDTH','s' => 'Manager','d' => 'User-defined extension to a request' },
+                    { 'n' => 'AWDOMAIN','w' => '2','s' => 'Manager','d' => 'Shareability domain of a request' },
+                    { 'n' => 'AWSNOOP','w' => 'AWSNOOP_WIDTH','s' => 'Manager','d' => 'Write request opcode' },
+                    { 'n' => 'AWSTASHNID','w' => '11','s' => 'Manager','d' => 'Stash Node ID' },
+                    { 'n' => 'AWSTASHNIDEN','w' => '1','s' => 'Manager','d' => 'Stash Node ID enable' },
+                    { 'n' => 'AWSTASHLPID','w' => '5','s' => 'Manager','d' => 'Stash Logical Processor ID' },
+                    { 'n' => 'AWSTASHLPIDEN','w' => '1','s' => 'Manager','d' => 'Stash Logical Processor ID enable' },
+                    { 'n' => 'AWTRACE','w' => '1','s' => 'Manager','d' => 'Trace signal' },
+                    { 'n' => 'AWLOOP','w' => 'LOOP_W_WIDTH','s' => 'Manager','d' => 'Loopback signals on the write channels' },
+                    { 'n' => 'AWMMUVALID','w' => '1','s' => 'Manager','d' => 'MMU signal qualifier' },
+                    { 'n' => 'AWMMUSECSID','w' => 'SECSID_WIDTH','s' => 'Manager','d' => 'Secure Stream ID' },
+                    { 'n' => 'AWMMUSID','w' => 'SID_WIDTH','s' => 'Manager','d' => 'StreamID' },
+                    { 'n' => 'AWMMUSSIDV','w' => '1','s' => 'Manager','d' => 'SubstreamID valid' },
+                    { 'n' => 'AWMMUSSID','w' => 'SSID_WIDTH','s' => 'Manager','d' => 'SubstreamID' },
+                    { 'n' => 'AWMMUATST','w' => '1','s' => 'Manager','d' => 'Address translated indicator' },
+                    { 'n' => 'AWMMUFLOW','w' => '2','s' => 'Manager','d' => 'SMMU flow type' },
+                    { 'n' => 'AWPBHA','w' => '4','s' => 'Manager','d' => 'Page-based Hardware Attributes' },
+                    { 'n' => 'AWNSAID','w' => '4','s' => 'Manager','d' => 'Non-secure Access ID' },
+                    { 'n' => 'AWSUBSYSID','w' => 'SUBSYSID_WIDTH','s' => 'Manager','d' => 'Subsystem ID' },
+                    { 'n' => 'AWATOP','w' => '6','s' => 'Manager','d' => 'Atomic transaction opcode' },
+                    { 'n' => 'AWMPAM','w' => 'MPAM_WIDTH','s' => 'Manager','d' => 'MPAM information with a request' },
+                    { 'n' => 'AWIDUNQ','w' => '1','s' => 'Manager','d' => 'Unique ID indicator' },
+                    { 'n' => 'AWCMO','w' => 'AWCMO_WIDTH','s' => 'Manager','d' => 'CMO type' },
+                    { 'n' => 'AWTAGOP','w' => '2','s' => 'Manager','d' => 'Memory Tag operation for write requests' },
+                    { 'n' => 'AWMECID','w' => 'MECID_WIDTH','s' => 'Manager','d' => 'Memory Encryption Context identifier' },
                 ]
             },
             {
@@ -293,6 +293,7 @@ sub get_axi_intf_data {
                 'signals' => [
                     { 'n' => 'WVALID', 'w' => '1', 's' => 'Manager', 'd' => 'Valid indicator' },
                     { 'n' => 'WREADY', 'w' => '1', 's' => 'Subordinate', 'd' => 'Ready indicator' },
+                    { 'n' => 'WID','w' => 'ID_W_WIDTH','s' => 'Manager','d' => 'Transaction identifier for the write channels' },
                     { 'n' => 'WDATA', 'w' => 'DATA_WIDTH', 's' => 'Manager', 'd' => 'Write data' },
                     { 'n' => 'WSTRB', 'w' => 'DATA_WIDTH_DIV_8', 's' => 'Manager', 'd' => 'Write data strobes' },
                     { 'n' => 'WTAG', 'w' => 'CEIL_DATA_WIDTH_DIV_128_TMS_4', 's' => 'Manager', 'd' => 'Memory Tag' },

scripts/vscode

@@ -0,0 +1,6 @@
+#!/bin/bash
+
+/opt/vscode/VSCode-linux-x64/code \
+    --enable-features=UseOzonePlatform,WaylandWindowDecorations \
+    --ozone-platform-hint=auto \
+    --unity-launch %F . & disown %1

src/axi/axi_manager_driver.sv

@@ -2,6 +2,10 @@
 // AXI Manager Driver
 // ----------------------------------------------------------------------
 class axi_manager_driver extends axi_driver;
+    axi_transaction txn_trk[axi_transaction_id_t];
+
+    semaphore write_request_sem;
+    semaphore read_request_sem;
 
     `uvm_component_utils(axi_manager_driver)
 
@@ -9,6 +13,9 @@ class axi_manager_driver extends axi_driver;
     // Constructor
     function new(string name = "axi_manager_driver", uvm_component parent = null);
         super.new(name, parent);
+
+        write_request_sem = new(1);
+        read_request_sem = new(1);
     endfunction
 
     // --------------------------------------------------
@@ -45,7 +52,14 @@ class axi_manager_driver extends axi_driver;
                 if (!$cast(req, txn)) begin
                     `uvm_fatal("drive_txn", "Invalid transaction type")
                 end
+                while (txn_trk.size() > (3-1)) begin
+                    `uvm_info("run_phase", $sformatf("Waiting for next transaction Txn-trk size=%0d to be under 3", txn_trk.size()), UVM_LOW)
+                    @(txn_trk.size());
+                    `uvm_info("run_phase", $sformatf("Txn-trk size changed to %0d to be under 3", txn_trk.size()), UVM_LOW)
+                end
+                fork
                     drive_txn(req);
+                join_none
                 seq_item_port.item_done();
             end
         end
@@ -54,7 +68,12 @@ class axi_manager_driver extends axi_driver;
     // ------------------------------------------------------------
     task drive_txn(axi_transaction req);
         int dly = cfg.get_pre_transaction_delay();
-        `uvm_info("drive_txn", $sformatf("Driving AXI transaction:\n%s", req.sprint()), UVM_LOW)
+        axi_transaction_id_t tid = req.get_tid();
+
+        `uvm_info("drive_txn", $sformatf("Driving AXI transaction ID=%s:\n%s",
+            req.show_tid(), req.sprint()), UVM_LOW)
+
+        txn_trk[tid] = req;
 
         // Pre transaction delay
         `uvm_info("drive_txn", $sformatf("Waiting pre_transaction_delay = %0d cycles",
@@ -69,39 +88,120 @@ class axi_manager_driver extends axi_driver;
             `uvm_error("drive_txn", $sformatf("Unknown transaction type: %s", req.txn_type.name()))
         end
         `uvm_info("drive_txn", $sformatf("Driving AXI transaction done."), UVM_LOW)
+
+        finish_tr(req);
+
+        txn_trk.delete(tid);
     endtask
 
     // ------------------------------------------------------------
     // Drive a write transaction
     task drive_write_txn(axi_transaction req);
+        bit done = 0;
+        bit a_done = 0;
+        bit w_done = 0;
+        bit b_done = 0;
+
+        `uvm_info("drive_write_txn", $sformatf("[%s] Waiting for semaphore to drive",
+            req.show_tag()), UVM_LOW)
+        write_request_sem.get();
+
+        // Drive address channel information
+        // TODO: Sometimes drive after delay
+        // TODO: Sometimes drive after waiting for AWREADY
         @(posedge m_if.ACLK);
         m_if.AWVALID = 1;
         m_if.AWADDR  = req.addr;
-        @(posedge m_if.ACLK);
+        m_if.AWID    = 0;
+
+        // Drive data channel information
+        // TODO: Sometimes drive after delay
+        // TODO: Sometimes drive after waiting for WREADY
+        m_if.WVALID = 1;
         m_if.WDATA  = req.data;
         m_if.WSTRB  = req.strb;
 
-        while (m_if.AWREADY != 1) begin
+        // Wait for write response
         @(posedge m_if.ACLK);
-        end
-        `uvm_info("drive_write_txn", $sformatf("Address phase accepted (AWREADY=1)"), UVM_LOW)
+        m_if.BREADY = 1;
+        while (!done) begin
+            @(posedge m_if.ACLK);
+
+            if (m_if.AWREADY == 1) begin
+                a_done = 1;
                 m_if.AWVALID = 0;
-        `uvm_info("drive_write_txn", $sformatf("Done."), UVM_LOW)
+            end
+            if (m_if.WREADY == 1) begin
+                w_done = 1;
+                m_if.WVALID = 0;
+            end
+
+            if (m_if.BVALID == 1) begin
+                b_done = 1;
+                m_if.BREADY = 0;
+            end
+
+            // Write is done when Address, Data and Response phases are done
+            done = (a_done && w_done && b_done);
+            `uvm_info("drive_write_txn", $sformatf("[%s] Waiting for transaction to be done (%b - a%b w%b b%b)",
+                req.show_tag(), done, a_done, w_done, b_done), UVM_LOW)
+        end
+
+        write_request_sem.put();
     endtask
 
     // ------------------------------------------------------------
     // Drive a read transaction
     task drive_read_txn(axi_transaction req);
+        bit done = 0;
+        bit a_done = 0;
+        bit r_done = 0;
+
+        `uvm_info("drive_read_txn", $sformatf("[%s] Waiting for semaphore to drive",
+            req.show_tag()), UVM_LOW)
+        read_request_sem.get();
+
+        // Drive address channel information
+        // TODO: Sometimes drive after delay
+        // TODO: Sometimes drive after waiting for AWREADY
         @(posedge m_if.ACLK);
         m_if.ARVALID = 1;
         m_if.ARADDR  = req.addr;
+        m_if.ARID    = 0;
+
+        // Wait for write response
+        @(posedge m_if.ACLK);
+        m_if.RREADY = 1;
+        while (!done) begin
             @(posedge m_if.ACLK);
 
-        while (m_if.ARREADY != 1) begin
-            @(posedge m_if.ACLK);
-        end
-        `uvm_info("drive_read_txn", $sformatf("Address phase accepted (ARREADY=1)"), UVM_LOW)
+            if (m_if.ARREADY == 1) begin
+                a_done = 1;
                 m_if.ARVALID = 0;
-        `uvm_info("drive_read_txn", $sformatf("Done."), UVM_LOW)
+            end
+
+            if (m_if.RVALID == 1) begin
+                r_done = 1;
+                m_if.RREADY = 0;
+            end
+
+            // Write is done when Address, Data and Response phases are done
+            done = (a_done && r_done);
+            `uvm_info("drive_read_txn", $sformatf("[%s] Waiting for transaction to be done (Data=0x%h) (%b - a%b r%b)",
+                req.show_tag(), m_if.RDATA, done, a_done, r_done), UVM_LOW)
+        end
+
+        read_request_sem.put();
     endtask
+
+    // ------------------------------------------------------------
+    // Mark transaction done
+    function void finish_tr(axi_transaction txn);
+        uvm_event finished_event;
+
+        finished_event = txn.get_event_pool().get("finished");
+        finished_event.trigger();
+        `uvm_info("finish_tr", $sformatf("[%s] Marked transaction done",
+            txn.show_tag()), UVM_LOW)
+    endfunction
 endclass : axi_manager_driver

src/axi/axi_monitor.sv

@@ -71,13 +71,13 @@ class axi_monitor extends uvm_monitor; // #(axi_transaction);
         forever begin
             @(posedge mon_if.ACLK);
             if (mon_if.ARESETn != 0) begin
-                if (mon_if.AWVALID == 1) begin
-                    $fwrite(trk_file, "AXI WRITE - ADDR=0x%h DATA=0x%h STRB=%h\n",
-                        mon_if.AWADDR, mon_if.WDATA, mon_if.WSTRB);
+                if ((mon_if.AWVALID == 1) && (mon_if.AWREADY == 1)) begin
+                    $fwrite(trk_file, "%10t: AXI WRITE - ADDR=0x%h DATA=0x%h STRB=%h\n",
+                        $time, mon_if.AWADDR, mon_if.WDATA, mon_if.WSTRB);
                 end
-                if (mon_if.ARVALID == 1) begin
-                    $fwrite(trk_file, "AXI READ - ADDR=0x%h\n",
-                        mon_if.ARADDR);
+                if ((mon_if.ARVALID == 1) && (mon_if.ARREADY == 1)) begin
+                    $fwrite(trk_file, "%10t: AXI READ - ADDR=0x%h\n",
+                        $time, mon_if.ARADDR);
                 end
             end
         end

src/axi/axi_subordinate_driver.sv

@@ -1,5 +1,10 @@
 // ----------------------------------------------------------------------
 class axi_subordinate_driver extends axi_driver;
+    int rd_txn_id = 0;
+    int wr_txn_id = 0;
+
+    semaphore write_request_sem;
+    semaphore read_request_sem;
 
     `uvm_component_utils(axi_subordinate_driver)
 
@@ -7,6 +12,9 @@ class axi_subordinate_driver extends axi_driver;
     // Constructor
     function new(string name = "axi_subordinate_driver", uvm_component parent = null);
         super.new(name, parent);
+
+        write_request_sem = new(1);
+        read_request_sem = new(1);
     endfunction
 
     // --------------------------------------------------
@@ -19,21 +27,22 @@ class axi_subordinate_driver extends axi_driver;
         end
 
         forever begin
-            @(posedge s_if.ARESETn);
+            @(s_if.ARESETn or s_if.ACLK);
 
-            while (s_if.ARESETn != 0) begin
-                @(posedge s_if.ACLK);
+            if (s_if.ARESETn == 0) continue;
 
-                // Following could happen on the same cycle
+            if (s_if.ACLK == 1) begin
                 if (s_if.AWVALID == 1'b1) begin
+                    fork
                         respond_to_write_txn();
+                    join_none
                 end
 
                 if (s_if.ARVALID == 1'b1) begin
+                    fork
                         respond_to_read_txn();
+                    join_none
                 end
-
-                @(negedge s_if.ACLK);
             end
         end
     endtask
@@ -43,22 +52,73 @@ class axi_subordinate_driver extends axi_driver;
         axi_transaction req;
         int dly = cfg.get_pre_response_delay();
 
+        while (s_if.AWVALID != 1) begin
+            `uvm_info("respond_to_write_txn", $sformatf("Waiting for AWVALID to set (%0b)",
+                s_if.AWVALID), UVM_LOW)
+            @(posedge s_if.ACLK);
+        end
+
+        if (!write_request_sem.try_get()) begin
+            `uvm_info("respond_to_write_txn", $sformatf("Already taken write semaphore"), UVM_LOW)
+            return;
+        end
+        // `uvm_info("respond_to_write_txn", $sformatf("Waiting for write semaphore"), UVM_LOW)
+        // write_request_sem.get();
+        `uvm_info("respond_to_write_txn", $sformatf("Got write semaphore"), UVM_LOW)
+
         req = axi_transaction::type_id::create("req");
+        req.set_sequence_id(1);
+        req.set_transaction_id(wr_txn_id);
+        wr_txn_id += 1;
         req.txn_type = AXI_WRITE;
-        req.addr = s_if.AWADDR;
-        req.data = s_if.WDATA;
-        req.strb = s_if.WSTRB;
 
         // Pre response delay
-        `uvm_info("drive_txn", $sformatf("Waiting pre_response_delay = %0d cycles",
-            dly), UVM_LOW)
+        `uvm_info("respond_to_write_txn", $sformatf("[%s] Waiting pre_response_delay = %0d cycles",
+            req.show_tag(), dly), UVM_LOW)
         repeat(dly) @(posedge s_if.ACLK);
 
-        `uvm_info("respond_to_write_txn", $sformatf("Responding to AXI write transaction:\n%s", req.sprint()), UVM_LOW)
+        `uvm_info("respond_to_write_txn", $sformatf("[%s] Responding to AXI write transaction:\n%s",
+            req.show_tag(), req.sprint()), UVM_LOW)
 
         s_if.AWREADY = 1'b1;
+        req.addr = s_if.AWADDR;
         @(posedge s_if.ACLK);
+        while (s_if.AWVALID != 0) begin
+            @(posedge s_if.ACLK);
+        end
         s_if.AWREADY = 1'b0;
+
+        `uvm_info("respond_to_write_txn", $sformatf("[%s] Request phase done. Waiting data phase",
+            req.show_tag()), UVM_LOW)
+        while (s_if.WVALID != 1) begin
+            `uvm_info("respond_to_write_txn", $sformatf("[%s] Waiting for WVALID to set (%0b)",
+                req.show_tag(), s_if.WVALID), UVM_LOW)
+            @(posedge s_if.ACLK);
+        end
+        s_if.WREADY = 1'b1;
+        req.data = s_if.WDATA;
+        req.strb = s_if.WSTRB;
+        @(posedge s_if.ACLK);
+        while (s_if.WVALID != 0) begin
+            `uvm_info("respond_to_write_txn", $sformatf("[%s] Waiting for WVALID to clear (%0b)",
+                req.show_tag(), s_if.WVALID), UVM_LOW)
+            @(posedge s_if.ACLK);
+        end
+        s_if.WREADY = 1'b0;
+
+        `uvm_info("respond_to_write_txn", $sformatf("[%s] Data phase done. Waiting response phase",
+            req.show_tag()), UVM_LOW)
+        s_if.BVALID = 1;
+        @(posedge s_if.ACLK);
+        while (s_if.BREADY != 1) begin
+            `uvm_info("respond_to_write_txn", $sformatf("[%s] Waiting for BREADY to set (%0b)",
+                req.show_tag(), s_if.BREADY), UVM_LOW)
+            @(posedge s_if.ACLK);
+        end
+        s_if.BVALID = 0;
+        `uvm_info("respond_to_write_txn", $sformatf("[%s] Response phase done",
+            req.show_tag()), UVM_LOW)
+        write_request_sem.put();
     endtask
 
     // ------------------------------------------------------------
@@ -66,19 +126,57 @@ class axi_subordinate_driver extends axi_driver;
         axi_transaction req;
         int dly = cfg.get_pre_response_delay();
 
+        while (s_if.ARVALID != 1) begin
+            `uvm_info("respond_to_read_txn", $sformatf("Waiting for ARVALID to be set (%0b)",
+                s_if.ARVALID), UVM_LOW)
+            @(posedge s_if.ACLK);
+        end
+
+        if (!read_request_sem.try_get()) begin
+            `uvm_info("respond_to_read_txn", $sformatf("Already taken read semaphore"), UVM_LOW)
+            return;
+        end
+        //  `uvm_info("respond_to_read_txn", $sformatf("Waiting for read semaphore"), UVM_LOW)
+        //  read_request_sem.get();
+        `uvm_info("respond_to_read_txn", $sformatf("Got read semaphore"), UVM_LOW)
+
         req = axi_transaction::type_id::create("req");
+        req.set_sequence_id(0);
+        req.set_transaction_id(rd_txn_id);
+        rd_txn_id += 1;
         req.txn_type = AXI_READ;
         req.addr = s_if.ARADDR;
 
         // Pre response delay
-        `uvm_info("respond_to_write_txn", $sformatf("Waiting pre_response_delay = %0d cycles",
+        `uvm_info("respond_to_read_txn", $sformatf("Waiting pre_response_delay = %0d cycles",
             dly), UVM_LOW)
         repeat(dly) @(posedge s_if.ACLK);
 
-        `uvm_info("respond_to_write_txn", $sformatf("Responding to AXI write transaction:\n%s", req.sprint()), UVM_LOW)
+        `uvm_info("respond_to_read_txn", $sformatf("Responding to AXI read transaction:\n%s",
+            req.sprint()), UVM_LOW)
 
         s_if.ARREADY = 1'b1;
         @(posedge s_if.ACLK);
+        while (s_if.ARVALID != 0) begin
+            `uvm_info("respond_to_read_txn", $sformatf("[%s] Waiting for ARVALID to clear (%0b)",
+                req.show_tag(), s_if.ARVALID), UVM_LOW)
+            @(posedge s_if.ACLK);
+        end
         s_if.ARREADY = 1'b0;
+
+        `uvm_info("respond_to_read_txn", $sformatf("[%s] Data phase done. Waiting response phase",
+            req.show_tag()), UVM_LOW)
+        s_if.RVALID = 1;
+        @(posedge s_if.ACLK);
+        while (s_if.RREADY != 1) begin
+            `uvm_info("respond_to_read_txn", $sformatf("[%s] Waiting for RREADY to set (%0b)",
+                req.show_tag(), s_if.RREADY), UVM_LOW)
+            @(posedge s_if.ACLK);
+        end
+        s_if.RVALID = 0;
+        `uvm_info("respond_to_read_txn", $sformatf("[%s] Response phase done",
+            req.show_tag()), UVM_LOW)
+
+        read_request_sem.put();
     endtask
 endclass : axi_subordinate_driver

src/axi/axi_transaction.sv

@@ -5,12 +5,16 @@ class axi_transaction extends uvm_sequence_item;
     rand bit [`ADDR_WIDTH-1:0]          addr; // Address
     rand bit [`DATA_WIDTH-1:0]          data; // Data
     rand bit [`DATA_WIDTH_DIV_8-1:0]    strb; // Byte enable
+    rand bit [2:0]                      size; // Size
+    rand bit [7:0]                      length; // Length
 
     `uvm_object_utils_begin(axi_transaction)
         `uvm_field_enum(axi_transaction_type_t, txn_type, UVM_DEFAULT)
         `uvm_field_int(addr, UVM_DEFAULT)
         `uvm_field_int(data, UVM_DEFAULT)
         `uvm_field_int(strb, UVM_DEFAULT)
+        `uvm_field_int(size, UVM_DEFAULT)
+        `uvm_field_int(length, UVM_DEFAULT)
     `uvm_object_utils_end
 
     // Constructor
@@ -18,6 +22,34 @@ class axi_transaction extends uvm_sequence_item;
         super.new(name);
     endfunction
 
+    // Get transaction id - made up of sequence ID and trasacton ID
+    function axi_transaction_id_t get_tid();
+        axi_transaction_id_t tid;
+
+        tid.seq_id = this.get_sequence_id();
+        tid.txn_id = this.get_transaction_id();
+
+        return tid;
+    endfunction
+
+    // Show transaction id - sequence ID:trasacton ID
+    function string show_tid();
+        return $sformatf("%0h:%0h", this.get_sequence_id(), this.get_transaction_id());
+    endfunction
+
+    // Show transaction tag - Transaction type:sequence ID:trasacton ID
+    function string show_tag();
+        return $sformatf("%s:%0h:%0h", this.txn_type.name(), this.get_sequence_id(), this.get_transaction_id());
+    endfunction
+
+    // Wait for transaction to be done
+    task wait_for_done();
+        uvm_event finished_event;
+
+        finished_event = get_event_pool().get("finished");
+        finished_event.wait_on();
+    endtask
+
     // Copy method for cloning
     virtual function uvm_object clone();
         axi_transaction copy;
@@ -26,6 +58,8 @@ class axi_transaction extends uvm_sequence_item;
         copy.addr = this.addr;
         copy.data = this.data;
         copy.strb = this.strb;
+        copy.size = this.size;
+        copy.length = this.length;
         return copy;
     endfunction
 
@@ -36,7 +70,9 @@ class axi_transaction extends uvm_sequence_item;
         return (this.txn_type == other.txn_type) &&
                (this.addr == other.addr) &&
                (this.data == other.data) &&
-               (this.strb == other.strb);
+               (this.strb == other.strb) &&
+               (this.size == other.size) &&
+               (this.length == other.length);
     endfunction
 
 endclass : axi_transaction

src/axi/axi_types.sv

@@ -1,13 +1,18 @@
 // AXI Types
 package axi_types;
+    typedef struct {
+        int seq_id;
+        int txn_id;
+    } axi_transaction_id_t;
+
     // Agent type
-    typedef enum {
-        MANAGER,
-        SUBORDINATE
+    typedef enum bit {
+        MANAGER     = 1'b0,
+        SUBORDINATE = 1'b1
     } axi_agent_type_t;
 
-    typedef enum {
-        AXI_READ,
-        AXI_WRITE
+    typedef enum bit {
+        AXI_READ    = 1'b0,
+        AXI_WRITE   = 1'b1
     } axi_transaction_type_t;
 endpackage

tb/tb_seq_base.sv

@@ -36,6 +36,7 @@ class axi_simple_seq extends axi_m_seq_base;
 
     // Task to start the sequence
     virtual task body();
+        axi_transaction txns[$];
         axi_transaction txn;
 
         super.body();
@@ -48,6 +49,16 @@ class axi_simple_seq extends axi_m_seq_base;
                 data != {`DATA_WIDTH{1'b0}};
                 strb == 'hf; // Example byte enable
             });
+            `uvm_info("axi_simple_seq", $sformatf("Starting %s transaction [%0s]",
+                txn.txn_type.name(), txn.show_tag()), UVM_LOW)
+            txns.push_back(txn);
+        end
+
+        `uvm_info("axi_simple_seq", $sformatf("Waiting for %0d txns", txns.size()), UVM_LOW)
+        foreach (txns[i]) begin
+            `uvm_info("axi_simple_seq", $sformatf("Waiting for txn %s", txns[i].show_tag()), UVM_LOW)
+            txns[i].wait_for_done();
+            `uvm_info("axi_simple_seq", $sformatf("Done waiting for txn %s", txns[i].show_tag()), UVM_LOW)
         end
     endtask
 endclass : axi_simple_seq

tb/test_base.sv

@@ -12,8 +12,12 @@ class test_base extends uvm_test;
 
     // ------------------------------------------------------------
     function void build_phase(uvm_phase phase);
+        uvm_root ur;
         super.build_phase(phase);
 
+        ur = uvm_root::get();
+        ur.set_timeout(10us);
+
         env = tb_env::type_id::create("env", this);
         tb_printer = new("tb_printer");
 

tb/verilator_trace_workaround.svh

@@ -49,6 +49,7 @@
     // A2.1.1 Write request channel
     always @(a_if.WVALID)            t_if.WVALID             <= a_if.WVALID;
     always @(a_if.WREADY)            t_if.WREADY             <= a_if.WREADY;
+    always @(a_if.WID)               t_if.WID                <= a_if.WID;
     always @(a_if.WDATA)             t_if.WDATA              <= a_if.WDATA;
     always @(a_if.WSTRB)             t_if.WSTRB              <= a_if.WSTRB;
     always @(a_if.WTAG)              t_if.WTAG               <= a_if.WTAG;