[libre-riscv-dev] Queue (FIFOControl) is awesome

[Luke Kenneth Casson Leighton]

i just created, to see what would happen, a 3-stage pipeline demo with
each set to fwft=True (first word write through).

with nmigen's SyncFIFO, the data fails to get through as a
combinatorial (same-cycle) write, even when fwft=True, if there is a
double-chain of SyncFIFOs.

with Queue, it *succeeds*.

in other words: a chain of Queue objects (with processing in between)
*may* act as a Combinatorial Block... or they each may switch over to
"store-and-forward" mode (independently, if each processing block has
the capability to stall) automatically.

it's really cool.

l.