Uvm_reg_data_t constraint randomization

UVM
1

When setting constraint for uvm_reg_field.value, should I specify the part select? since its type uvm_reg_data_t is a 64 bits unsigned variable.

For example, if the bit width of a field is only 3 bits, and I want to constraint it to be larger than 0.
Should I use field.value > 0 or field.value[2:0] > 0?

Will the former yield a random value like 64’h1234567812345670 which the 3 lsb are 0 which I don’t want?

2

constraint_without_part_select - EDA Playground
I tested and the answer is yes, you need to add part select.

3

Actually don’t need, there is a constraint in uvm_reg_field that don’t need us to do part select…

   constraint uvm_reg_field_valid {
      if (`UVM_REG_DATA_WIDTH > m_size) {
         value < (`UVM_REG_DATA_WIDTH'h1 << m_size);
      }
   }