在sequence中可以使用starting_phase来控制验证平台的关闭。
有两种方式为starting_phase赋值。
第一种:手工启动sequence时为starting_phase赋值。
例如:seq.start(env.i_agt.sqr);
class my_case0 extends base_test;
function new(string name = "my_case0", uvm_component parent = null);
super.new(name,parent);
endfunction
`uvm_component_utils(my_case0)
extern virtual task main_phase(uvm_phase phase);
endclass
task my_case0::main_phase(uvm_phase phase);
sequence0 seq0;
sequence1 seq1;
seq0 = new("seq0");
seq0.starting_phase = phase;
seq1 = new("seq1");
seq1.starting_phase = phase;
fork
seq0.start(env.i_agt.sqr);
seq1.start(env.i_agt.sqr);
join
endtask
第二种:将此sequence作为sequencer的某动态运行phase的default_phase时,starting_phase不为null。
function void my_case0::build_phase(uvm_phase phase);
super.build_phase(phase);
uvm_config_db#(uvm_object_wrapper)::set(this, //
"env.i_agt.sqr.main_phase", //
"default_sequence", //
case0_sequence::type_id::get());//
endfunction
但是如果将某sequence作为uvm_do宏的参数,那么此sequence中的starting_phase为null。
class drv0_seq extends uvm_sequence #(my_transaction);
my_transaction m_trans;
`uvm_object_utils(drv0_seq)
function new(string name= "drv0_seq");
super.new(name);
endfunction
virtual task body();
if(starting_phase != null) begin //
starting_phase.raise_objection(this); //
`uvm_info("drv0_seq", "raise_objection", UVM_MEDIUM)
end else begin
`uvm_info("drv0_seq", "starting_phase is null", UVM_MEDIUM)
end
if(starting_phase != null)
starting_phase.drop_objection(this);
endtask
endclass
class case0_vseq extends uvm_sequence;
`uvm_object_utils(case0_vseq)
`uvm_declare_p_sequencer(my_vsqr)
function new(string name = "case0_vseq");
super.new(name);
endfunction
virtual task body();
my_transaction tr;
drv0_seq seq0;
if(starting_phase != null) //
starting_phase.raise_objection(this); //
`uvm_do_on(seq0, p_sequencer.p_sqr0); //
#100;
if(starting_phase != null) //
starting_phase.drop_objection(this); //
endtask
endclass
运行上述代码,会发现drv0_seq中的starting_phase为null,从而不会对objection进行操作。