Make EFC firmware build from JSON, instead of CLI arguments

[thomasfire]

ARTIQ Pull Request

Description of Changes

Make EFC firmware build from JSON, instead of CLI arguments.

Related Issue

Closes #2405

Type of Changes

	Type
✓	:sparkles: New feature

Steps

Tested by building with python -m artiq.gateware.targets.efc efct.json. The efct.json file:

{
    "target": "efc",
    "min_artiq_version": "7.0",
    "variant": "shuttler_test",
    "hw_rev": "v1.1",
    "peripherals": []
}

All Pull Requests

• [x] Use correct spelling and grammar.
• [ ] Update RELEASE_NOTES.rst if there are noteworthy changes, especially if there are changes to existing APIs.
• [ ] Close/update issues.
• [x] Check the copyright situation of your changes and sign off your patches (git commit --signoff, see copyright).

Licensing

See copyright & licensing for more info. ARTIQ files that do not contain a license header are copyrighted by M-Labs Limited and are licensed under LGPLv3+.

[sbourdeauducq]

How does this fit into AFWS? Obviously the purpose of doing this is to support our customers with EFC/Shuttler firmware builds for their systems.

[thomasfire]

How does this fit into AFWS? Obviously the purpose of doing this is to support our customers with EFC/Shuttler firmware builds for their systems.

python -m artiq.gateware.targets.efc efct.json?

[sbourdeauducq]

The entries for shuttler are already in the JSON with another format, which just currently lacks the hardware revision and/or its handling. Whether they need to be handled in ARTIQ or AFWS is a question that should be explored. The current EFC build system does not really need JSON, command line arguments are enough.

[sbourdeauducq]

python -m artiq.gateware.targets.efc efct.json

AFWS is not currently capable of running this anyway.