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Identifying clock domain crossing paths counted during report_clock_transfer?

Altera_Forum
Honored Contributor II
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I have a design with 4 clock domains (SerialClock, pll_clock40, pll_clock80, and SerialTxClock). 

 

The report_clock_transfer command in the TimeQuest GUI finishes in about 1-2 seconds. 

 

It reports that I have 1529 paths crossing from SerialClock to pll_clock40.  

 

I can get a list of all those paths, to identify the start point and end point, with the command: 

 

report_timing -setup -from_clock SerialClock -to_clock pll_clock40 -detail summary -npaths 1529 

 

It can report that to a panel or to a file in 1-2 seconds. No problem so far. 

 

 

report_clock_transfer also indicates I have 1,329,471 paths from pll_clock40 to pll_clock80 

 

The command  

 

report_timing -from_clock { pll_clock40 } -to_clock { pll_clock80 } -setup -npaths 1329471 -detail summary -file outfile.rpt -append 

 

has not finished after 48 hours. 

 

This is roughly 1000x more paths than in the first set of reports, but there is no output yet after nearly 200,000x the runtime. 

 

My CPU is not overloaded and my PC is not out of memory. (This is a small Cyclone III design.) 

 

 

I don't even need a full timing report or summary of timing, just a list of all the startpoints and endpoints so we can confirm the transfers are handled properly. (It's a design I inherited, not my own design.) 

 

 

Since report_clock_transfers completes the entire analysis in 1-2 seconds, there must be a faster way to get the path information than by running the report_timing command. 

 

Does anyone know how to do this? 

 

 

 

FWIW, the design was built in and must be finished with Quartus II v9.1.sp1 

 

But if newer versions of Quartus have commands that generate this info directly, or can just finish my reports quickly, I can use them for collecting the path info. 

 

 

Thanks very much!
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