How does the pathfinder algorithm work in FPGA routing? I have an oral exam on this topic next week... so can anyone explain the two iterations clearly with an example may be.
Here's what I understood after reading multiple research papers.
Algorithm runs in iterations
first iteration:
route every connection with minimum delay, even if there is
congestion
Second iteration
iterate as long as congestion exists
rip-up and re-route every net in the circuit
the cost of using a congested routing resource is increased from iteration to iteration
at the end of an iteration, we have a complete routing (but maybe with congestion); determine the delays and slacks of all connections