uvm_config_db note

uvm_config_db_note.md

Why using

• Avoid dependent between object.
• Avoid OOP restriction when use factory override.
  • For example: if we assign object directly top_env.module_a_agent.m_obj = m_obj; However, the m_obj only exist in the overriden type of module a agent --> issue.
• In sequence to get data, comp handle.

Why not using

• From uvm cookbook, intensive use of uvm_config_db slows simulation
  • Only use with class type, not primitive type variable.
  • Do not polling for change from uvm_config_db.
  • Use specific path/inst, do not use "*".