cfs_apb_coverage.sv

`ifndef CFS_APB_COVERAGE_SV
  `define CFS_APB_COVERAGE_SV

  class cfs_apb_coverage extends uvm_ext_coverage#(.VIRTUAL_INTF(cfs_apb_vif), .ITEM_MON(cfs_apb_item_mon));
    
    //Pointer to agent configuration
    cfs_apb_agent_config agent_config;
    
    //Wrapper over the coverage group covering the indices in the PADDR signal
    //at which the bit of the PADDR was 0
    uvm_ext_cover_index_wrapper#(`CFS_APB_MAX_ADDR_WIDTH) wrap_cover_addr_0;

    //Wrapper over the coverage group covering the indices in the PADDR signal
    //at which the bit of the PADDR was 1
    uvm_ext_cover_index_wrapper#(`CFS_APB_MAX_ADDR_WIDTH) wrap_cover_addr_1;

    //Wrapper over the coverage group covering the indices in the PWDATA signal
    //at which the bit of the PWDATA was 0
    uvm_ext_cover_index_wrapper#(`CFS_APB_MAX_DATA_WIDTH) wrap_cover_wr_data_0;

    //Wrapper over the coverage group covering the indices in the PWDATA signal
    //at which the bit of the PWDATA was 1
    uvm_ext_cover_index_wrapper#(`CFS_APB_MAX_DATA_WIDTH) wrap_cover_wr_data_1;

    //Wrapper over the coverage group covering the indices in the PRDATA signal
    //at which the bit of the PRDATA was 0
    uvm_ext_cover_index_wrapper#(`CFS_APB_MAX_DATA_WIDTH) wrap_cover_rd_data_0;

    //Wrapper over the coverage group covering the indices in the PRDATA signal
    //at which the bit of the PRDATA was 1
    uvm_ext_cover_index_wrapper#(`CFS_APB_MAX_DATA_WIDTH) wrap_cover_rd_data_1;

    `uvm_component_utils(cfs_apb_coverage)
    
    covergroup cover_item with function sample(cfs_apb_item_mon item);
      option.per_instance = 1;
      
      direction : coverpoint item.dir {
        option.comment = "Direction of the APB access";
      }
      
      response : coverpoint item.response {
        option.comment = "Response of the APB access";
      }
      
      length : coverpoint item.length {
        option.comment = "Length of the APB access";
        bins length_eq_2     = {2};
        bins length_le_10[8] = {[3:10]};
        bins length_gt_10    = {[11:$]};
        
        illegal_bins length_lt_2 = {[$:1]};
      }
      
      prev_item_delay : coverpoint item.prev_item_delay {
        option.comment = "Delay, in clock cycles, between two consecutive APB accesses";
        bins back2back       = {0};
        bins delay_le_5[5]   = {[1:5]};
        bins delay_gt_5      = {[6:$]};
      }
      
      response_x_direction : cross response, direction;
      
      trans_direction : coverpoint item.dir {
        option.comment = "Transitions of APB direction";
        bins direction_trans[] = (CFS_APB_READ, CFS_APB_WRITE => CFS_APB_READ, CFS_APB_WRITE);
      }
      
    endgroup
    
    covergroup cover_reset with function sample(bit psel);
      option.per_instance = 1;
      
      access_ongoing : coverpoint psel {
        option.comment = "An APB access was ongoing at reset";
      }
    endgroup
    
    function new(string name = "", uvm_component parent);
      super.new(name, parent);
      
      cover_item = new();
      cover_item.set_inst_name($sformatf("%s_%s", get_full_name(), "cover_item"));
      
      cover_reset = new();
      cover_reset.set_inst_name($sformatf("%s_%s", get_full_name(), "cover_reset"));
    endfunction
    
    virtual function void build_phase(uvm_phase phase);
      super.build_phase(phase);
      
      wrap_cover_addr_0    = uvm_ext_cover_index_wrapper#(`CFS_APB_MAX_ADDR_WIDTH)::type_id::create("wrap_cover_addr_0",    this);
      wrap_cover_addr_1    = uvm_ext_cover_index_wrapper#(`CFS_APB_MAX_ADDR_WIDTH)::type_id::create("wrap_cover_addr_1",    this);
      wrap_cover_wr_data_0 = uvm_ext_cover_index_wrapper#(`CFS_APB_MAX_DATA_WIDTH)::type_id::create("wrap_cover_wr_data_0", this);
      wrap_cover_wr_data_1 = uvm_ext_cover_index_wrapper#(`CFS_APB_MAX_DATA_WIDTH)::type_id::create("wrap_cover_wr_data_1", this);
      wrap_cover_rd_data_0 = uvm_ext_cover_index_wrapper#(`CFS_APB_MAX_DATA_WIDTH)::type_id::create("wrap_cover_rd_data_0", this);
      wrap_cover_rd_data_1 = uvm_ext_cover_index_wrapper#(`CFS_APB_MAX_DATA_WIDTH)::type_id::create("wrap_cover_rd_data_1", this);
    endfunction

    virtual function void end_of_elaboration_phase(uvm_phase phase);
      super.end_of_elaboration_phase(phase);
      
      if($cast(agent_config, super.agent_config) == 0) begin
        `uvm_fatal("ALGORITHM_ISSUE", $sformatf("Could not cast %0s to %0s!", super.agent_config.get_type_name(), cfs_apb_agent_config::type_id::type_name))
      end      
    endfunction
    
    //Port associated with port_item port
    virtual function void write_item(cfs_apb_item_mon item);
      cover_item.sample(item);
      
      for(int i = 0; i < `CFS_APB_MAX_ADDR_WIDTH; i++) begin
        if(item.addr[i]) begin
          wrap_cover_addr_1.sample(i);
        end
        else begin
          wrap_cover_addr_0.sample(i);
        end
      end
      
      for(int i = 0; i < `CFS_APB_MAX_DATA_WIDTH; i++) begin
        case(item.dir)
          CFS_APB_WRITE : begin
            if(item.data[i]) begin
              wrap_cover_wr_data_1.sample(i);
            end
            else begin
              wrap_cover_wr_data_0.sample(i);
            end
          end
          CFS_APB_READ : begin
            if(item.data[i]) begin
              wrap_cover_rd_data_1.sample(i);
            end
            else begin
              wrap_cover_rd_data_0.sample(i);
            end
          end
          default : begin
            `uvm_error("ALGORITHM_ISSUE", $sformatf("Current version of the code does not support item.dir: %0s", item.dir.name()))
          end
        endcase
      end
    endfunction
    
    //Function to handle the reset
    virtual function void handle_reset(uvm_phase phase);
      cfs_apb_vif vif = agent_config.get_vif();
      
      cover_reset.sample(vif.psel);
    endfunction
    
    // Function to print the coverage information
    virtual function string coverage2string();
        string result = {
            $sformatf("\ncover_item             : %03.2f%%", cover_item.get_inst_coverage()),
            $sformatf("\ndirection              : %03.2f%%", cover_item.direction.get_inst_coverage()),
            $sformatf("\ntrans_direction        : %03.2f%%", cover_item.trans_direction.get_inst_coverage()),
            $sformatf("\nresponse               : %03.2f%%", cover_item.response.get_inst_coverage()),
            $sformatf("\nresponse_x_direction   : %03.2f%%", cover_item.response_x_direction.get_inst_coverage()),
            $sformatf("\nlength                 : %03.2f%%", cover_item.length.get_inst_coverage()),
            $sformatf("\nprev_item_delay        : %03.2f%%", cover_item.prev_item_delay.get_inst_coverage()),
            $sformatf("\n"),
            $sformatf("\ncover_reset            : %03.2f%%", cover_reset.get_inst_coverage()),
            $sformatf("\naccess_ongoing         : %03.2f%%", cover_reset.access_ongoing.get_inst_coverage()),
            super.coverage2string()
        };
        
        return result;
    endfunction    
  endclass
`endif // CFS_APB_COVERAGE_SV