support loading device from json

[mia8973]

Co-Authored-By: Claude Opus 4.6 noreply@anthropic.com

[yrabbit]

Hmm... pnr[‘modules’][‘top’][‘settings’][‘packer.partno’] was supposed to be used to select a device, but then it turned out that Gowin's most detailed PARTNO is not a unique identifier: GW1N-9C and GW1N-9 are completely different chips, but you can't tell that from the PARTNO.

The same story with GW2A-18 and GW2A-18C.

You can easily see this if you try to compile blinky-clkdiv-tangnano9k.fs in the examples directory without specifying a device for gowin_pack.

[mia8973]

it looks like it was meant to be supported by the parsing of the part number out of the device isn't complete enough i think that you dcan just use the partdb field insteaed i tried it and it workd

[yrabbit]

packer.chipdb

This will naturally work because it is effectively the name of the chip base 😄

[yrabbit]

Usually, the set of Python libraries used remains unchanged. This is because Apicula is often included as part of a large package, and the feasibility of including/replacing third-party packages must be proven with blood, sweat, and tears.

You can use anything locally (after all, it's just a Python file), but you need to have very good reasons for changing the distribution set.