The /boards directory contains the physical hardware platforms that Tock supports.

Tock divides boards into three approximate 'tiers' of support. These tiers are newly defined and are a bit informal as a result, but the approximate definitions:

• Tier 1: The most feature-complete and thoroughly tested boards. These are boards used most regularly by core team members or other highly engaged contributors. They are used as examples in the Tock Book.

• Tier 2: Platforms seeing reasonably regular use. These generally have broader, but still incomplete, peripheral support. They may also be 'relatives' of Tier 1 boards (e.g. a less-used variant in the nrf52 family) – likely in good shape, but not heavily tested. Some Tier 2 boards may have known issues, which are documented in release notes during release testing.

• Tier 3: New or highly experimental. These should support the minimum platform requirements laid out in the Porting documentation, but make no promises beyond that.

• Other: See each board for specific details.

RISC-V?

Tock has solid support for the RISC-V architecture, but no tier 1 or 2 support for any single RISC-V board. If you are interested in running Tock on RISC-V there are a few options:

1. If you would like a cheap RISC-V development board you can use the ESP32-C3-DevKitM-1. This board is under active development to move to Tier 2 support.
2. For a fully virtual platform on QEMU you can use the QEMU RISC-V 32 bit virt platform board. This can be quickly started and run on a host computer.
3. For a simulation environment you can use Verilator with OpenTitan Earlgrey on CW310 or Verilated LiteX Simulation.
4. For an FPGA setup you can use OpenTitan Earlgrey on CW310 or LiteX on Digilent Arty A-7.

An FPGA and Verilator implementation that is well supported and is regularly tested as part of CI.

Virtual hardware platforms that are regularly tested as part of the CI.

Some projects that use Tock maintain their own board definitions outside the Tock repository.