tang_nano_9k.py toolchain_program() writes to RAM not Flash

[DaveBerkeley]

The default toolchain_program() for https://github.com/amaranth-lang/amaranth-boards/blob/main/amaranth_boards/tang_nano_9k.py uses openFPGALoader.

It lacks the "-f" option that writes to flash, so only programs the RAM. If you want persistent FPGA programming you need the "-f" option.

Not sure how this should be handled. Is there a way of adding programmer options, eg via the environment?

[whitequark]

No, or at least, this particular board doesn't implement it: the function you see there is all there is to it. Since it is only 2 lines, I think copying it into your own code and modifying as you'd like (you can inherit from the platform too) would work fine.

I'm not sure if we've had a similar problem elsewhere and solved it there; if we did, I'm happy to merge a copy of that code to this board.

[DaveBerkeley]

Okay, thanks. I wonder if there should be a -flash option at a higher level? Similar to the do_program option on platform.build() that ends up at toolchain_program(). Anything using openFPGALoader could have the same fix.

I can't see a fix for this elsewhere in the repo. Maybe people don't have an issue with it. I've mostly been using Lattice FPGAs and the default there is to write to flash using iceprog. With openFPGALoader is would need the extra flag.