I cannot find the U54 or U74 arty bitstreams. AFAICT there are no bitstreams included in the respective SDKs currently. I have checked multiple versions and also I cross-checked the E76 SDK, which does include the bitstream exactly as documented but none of the U* versions does.
I would be also fine to synthesize it myself if there were an easy way to do so (e.g., a makefile).
Our free platforms, basically rocket chip plus some peripherals, can be found at
This includes U500 support for the vc707 fpga board.
I’m not a hardware guy, so I can’t comment on the rest of this.
Thank you for pointing out this issue. While u74 is too large to fit on an arty FPGA, the lack of u54 tarballs with arty bitstream was an oversight, since support for them is a new feature. The u54 tarballs on the website have been updated to include this feature, if you download it, you should see it is named as “19.08p0p1”