In reply to saravanantvs:
One of the key features is the separation of test from the testbench. In the test you are constructing the testbench which is customized to the needs of this test. And you are selecting the sequence which contains the functionality for this test. Of course you are doing somthing else like passing the virtual interface and configuration data to testbench components.
Typically I’m using a test base class which is doing all the things relevant for all tests and a specific test class which extends the test base class. See an example below:
//-----------------------------------------------------------------------------
class example_top_base_test extends uvm_test;
//-----------------------------------------------------------------------------
`uvm_component_utils(example_top_base_test)
apb_config apb_cfg;
spi_config spi_cfg;
example_top_config cfg;
example_top_env env;
extern function new(string name = “example_top_base_test”, uvm_component parent = null);
extern function void build_phase(uvm_phase phase);
endclass : example_top_base_test
//---------------------------------------------------------------------------
// Implementation
//---------------------------------------------------------------------------
function example_top_base_test::new(string name = “example_top_base_test”, uvm_component parent = null);
super.new(name, parent);
endfunction : new
function void example_top_base_test::build_phase(uvm_phase phase);
super.build_phase(phase);
// Create top config
cfg = example_top_config::type_id::create(“cfg”);
// Create sub config
apb_cfg = apb_config::type_id::create(“apb_cfg”);
spi_cfg = spi_config::type_id::create(“spi_cfg”);
if(!uvm_config_db #(virtual apb_if)::get(this, “”, “apb_if_i”, apb_cfg.vif))
`uvm_error(get_type_name(), “no virtual interface found”)
if(!uvm_config_db #(virtual spi_if)::get(this, “”, “spi_if_i”, spi_cfg.vif))
`uvm_error(get_type_name(), “no virtual interface found”)
cfg.apb_cfg = apb_cfg;
cfg.spi_cfg = spi_cfg;
uvm_config_db #(example_top_config)::set(this, “env”, “example_top_config”, cfg);
// Create env
env = example_top_env::type_id::create(“env”, this);
endfunction : build_phase
And her ea specific test:
//-----------------------------------------------------------------------------
class example_top_test1 extends example_top_base_test;
//-----------------------------------------------------------------------------
`uvm_component_utils(example_top_test1)
extern function new(string name = “example_top_test1”, uvm_component parent = null);
extern virtual function void build_phase(uvm_phase phase);
extern task run_phase(uvm_phase phase);
//---------------------------------------------------------------------------
// constraints
//---------------------------------------------------------------------------
endclass : example_top_test1
//---------------------------------------------------------------------------
function example_top_test1::new(string name = “example_top_test1”, uvm_component parent = null);
super.new(name,parent);
endfunction : new
function void example_top_test1::build_phase(uvm_phase phase);
uvm_config_db#(int)::set(this, “env.apb_env_i.agent”, “is_active”, UVM_ACTIVE);
uvm_config_db#(int)::set(this, “env.spi_env_i.agent”, “is_active”, UVM_ACTIVE);
super.build_phase(phase);
endfunction : build_phase
task example_top_test1::run_phase(uvm_phase phase);
example_top_default_seq vseq = example_top_default_seq::type_id::create(“vseq”);
phase.raise_objection(this, “Starting virtual sequence”);
uvm_info(get_type_name(), "Objection raised", UVM_MEDIUM) vseq.start(null); phase.drop_objection(this, "Finished virtual sequence"); uvm_info(get_type_name(), “Objection dropped”, UVM_MEDIUM)
endtask : run_phase
The virtual sequence looks like this:
class example_top_default_seq extends example_top_base_seq;
`uvm_object_utils(example_top_default_seq)
// UVC sequences
apb_default_seq apb_seq;
spi_default_seq spi_seq;
extern function new(string name = “example_top_default_seq”);
extern task body();
endclass : example_top_default_seq
Here iis the body task implementation:
task example_top_default_seq::body();
super.body();
apb_seq = apb_default_seq::type_id::create(“apb_seq”);
spi_seq = spi_default_seq::type_id::create(“spi_seq”);
`uvm_info(get_type_name(),“default sequence starting”, UVM_MEDIUM)
repeat(10) begin
`uvm_info(get_type_name(),“apb sequence starting”, UVM_MEDIUM)
void’(apb_seq.randomize());
apb_seq.start(apb_sequencer_i);
`uvm_info(get_type_name(),“spi sequence starting”, UVM_MEDIUM)
void’(spi_seq.randomize());
spi_seq.start(spi_sequencer_i);
end
`uvm_info(get_type_name(),“default sequence completed”,UVM_MEDIUM)
endtask : body
Hope this helps to answer your question.