[prim] Latch Enable signal for Sparse FSM macro

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[prim] Latch Enable signal for Sparse FSM macro #14631

Open eunchan opened 2 years ago

eunchan commented 2 years ago

prim_flop_macros.sv defines PRIM_FLOP_SPARSE_FSM() macro. It makes the sparse fsm FFs simple. However, the prim_sparse_fsm_flop module does not have a latch enable signal, which is useful in certain cases.

This issue is to track the enhancement:

Add latch_en port in prim_sparse_fsm_flop module
Revise PRIM_FLOP_SPARSE_FSM() macro to have optional __en argument, (default tied to 1'b1).

tjaychen commented 2 years ago

sounds good to me. Is there an example of where the __en might be useful?

eunchan commented 2 years ago

sounds good to me. Is there an example of where the __en might be useful?

About to create a PR :) Let me link here.

eunchan commented 2 years ago

PR #14633 has been created.

msfschaffner commented 2 years ago

Sounds good, although it we should probably check with the DV folks whether this affects any of the common DV infrastructure testing sparse FSMs.