[Libre-soc-dev] FPGAs progress

[lkcl]

i've been working on getting libresoc and microwatt running on FPGA boards, and slowly putting together an SoC fabric using lambdasoc.

 here is the status so far:

* VERSA ECP5 45K runs microwatt and libresoc at 55 mhz
* ULX3S ECP5 85K runs microwatt at 40 mhz but libresoc ar only 12.5 mhz
* Arty A7 100t using symbiflow runs microwatt at 25 mhz but cannot run libresoc at all
* Arty a7 100t using symbiflow will however run blinky lights demos

apparently, larger FPGAs have routing problems, it is "just one of those things" which means it may be necessary to put in additional DFFs to break things up.

also i am experimenting with nextpnr-xilinx on the arty a7 100t, and have successfully got blinky lights working but not anything else yet: this is with nmigen.

also on order are two orangecrab boards, going to tobias who is in germany, one then comes to me.

i want to get everyone who is interested in contributing more an FPGA board, ramping up from the smaller ones (85k LUT4s) to something monstrous (500k LUT4s) because we will need it.

l.