Dear All,
could someone give me a hint on a correct 'methodology'? Having a testbench to test single entity I'd like to use its parts in a testbench which tests one-hierarchy-level above entity. Example:

have entity TLV5637 which uses 1us clock enable. The entity instantiates 'clock_divider', which provides me with this signal. In the testbench I have a process which verifies whether the 1us clock enable is really 1us.

have upper entity DAC_TREATMENT, which instantiates TLV5637. The testbench for DAC treatment should test the 1us clock enable length as well.

Is there any way how to re-use part of the testbench which was already created for TLV5637? Shall I put the part of the code into package and then use the package?

What is the correct approach to make generic tests like those?