UVM Tutorial for Candy Lovers – 9. Register Abstraction

This post will explain how to use the UVM Register Abstraction Layer (RAL) to generate register transactions. The figure below shows the verification platform used for this post. Among other things, the jelly_bean_reg_block, the jelly_bean_reg_adapter, and the jelly_bean_reg_predictor are the classes used for the register abstraction.
The figure below shows the diagram of the RAL-related classes. The standard UVM classes are shown in pink, while the jelly-bean classes are shown in light blue. The diagram looks busy, but bear in mind that I will explain each jelly-bean class one by one.

Register Definitions

In the previous posts, the DUT had no accessible registers. We are going to add the registers that hold jelly-bean recipe information and its taste. We will also add a command input port to the DUT so that we can write a jelly-bean recipe to the register and read its taste. The figure below shows the register definition of the DUT.

The source code of the DUT (jelly_bean_taster) is shown below. When the command input is WRITE, the values of flavor, color, sugar_free, and sour input ports are written to the RECIPE register (line 22 to 25). When the command input is READ, the TASTE register is read out and the taste output is driven accordingly (line 27).

module jelly_bean_taster( jelly_bean_if.slave_mp jb_slave_if );
   import jelly_bean_pkg::*;
 
   reg [2:0] flavor;
   reg [1:0] color;
   reg       sugar_free;
   reg       sour;
   reg [1:0] command;
   reg [1:0] taste;
 
   initial begin
      flavor     = 0;
      color      = 0;
      sugar_free = 0;
      sour       = 0;
      command    = 0;
      taste      = 0;
   end
 
   always @ ( posedge jb_slave_if.clk ) begin
      if ( jb_slave_if.command == jelly_bean_types::WRITE ) begin
         flavor     < = jb_slave_if.flavor;         color      <= jb_slave_if.color;         sugar_free <= jb_slave_if.sugar_free;         sour       <= jb_slave_if.sour;      end else if ( jb_slave_if.command == jelly_bean_types::READ ) begin
         jb_slave_if.taste <= taste;      end
   end
 
   always @ ( posedge jb_slave_if.clk ) begin
      if ( jb_slave_if.flavor == jelly_bean_types::CHOCOLATE &&
           jb_slave_if.sour ) begin
         taste <= jelly_bean_types::YUCKY;
      end else if ( jb_slave_if.flavor != jelly_bean_types::NO_FLAVOR ) begin
         taste <= jelly_bean_types::YUMMY;
      end
   end
endmodule: jelly_bean_taster

标签：Abstraction,Register,jelly,Candy,bean,command,flavor,reg,register
来源： https://blog.csdn.net/zt5169/article/details/110421076