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Yosys Open SYnthesis Suite
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Should -nomx8 be the default for the GateMate? #4355

Open spth opened 2 months ago

spth commented 2 months ago

Version

Yosys 0.40 (git sha1 a1bb0255d65, g++ 13.2.0-13 -fPIC -Os)

On which OS did this happen?

Linux

Reproduction Steps

Synthesize a non-trivial design for the GateMate FPGA using default options.

Expected Behavior

yosys will synthesize something that can be used by the GateMate P&R tool.

This expected behaviour can actually be achieved by using -nomx8. So maybe that should be the default? AFAIK there is currently no P&R tool that can handle the MX8 cells (and I don't know if nextpnr will be able to do so, when it gets GateMate support).

Actual Behavior

yosys will likely use MX8 cells (I tested both yosys 0.38 and yosys 0.40). MX8 cells haven't been supported in the GateMate P&R tool for many months, so P&R will fail.