Hyperdebug Firmware

This repository provides the build and release process for the hyperdebug firmware used by the OpenTitan project. Hyperdebug is a standard NUCLEO-L552ZE-Q board that provide debug and I/O connectivity with the OpenTitan FPGA development board.

The hyperdebug firmware is a variant of the Chromium EC firmware.

Updating

This repository does not contain the Chromium EC source code. Instead, we reference Chromium's git repository at the commit that contains the features we need for hyperdebug (this allows the hyperdebug firmware release to be independent from EC releases).

To change the version of EC firmware used as hyperdebug firmware, update the git_repository rule in //third_party/chromium/repos.bzl.

git_repository(
    name = "ec_src",
    remote = "https://chromium.googlesource.com/chromiumos/platform/ec",
    commit = "17c8bc295fb6c2a258efadb4a52f04a0f494ec0d",
    build_file = "//third_party/chromium:BUILD.ec_src.bazel",
)

After updating the rule, build and release the new firmware.

Building

To build the hyperdebug firmware, issue the following command:

bazel build :hyperdebug-firmware

This will emit a hyperdebug-firmware.tar.gz archive containing the firmware binary and support files.

Releasing

To perform a release of the firmware, use the Create Release flow in the Actions tab. It is suggested that you use a release_tag patterned after the build date: YYYYMMDD_RR, where:

• YYYY is the year.
• MM is the month.
• DD is the day.
• RR is the number of the release on that date, starting at 01.

To perform a manual release of the firmware, issue the following command:

RELEASE_TAG="YYYYMMDD_RR"
bazel run :release -- ${RELEASE_TAG}

This will build the firmware archive, create a git tag and publish the release artifacts to github.