Device firmware
Caution: This page may contain information that is specific to the legacy version of the driver framework (DFv1).
Device firmware are binary blobs containing code that are executed by device hardware. The binary blob is available in the driver's namespace for loading.
Device firmware are stored in CIPD (Chrome Infrastructure Package Deployment) and mirrored in Google Storage.
Create a Firmware Package
To create a firmware package, create a directory containing the following files:
- One or more firmware files
- A license file
- README.fuchsia
README.fuchsia must contain at least the following directives:
NameVersionUpstream GitLicenseLicense File
If this is the first time you uploaded to CIPD from the host system, authenticate with CIPD:
Upload and tag the package in CIPD using the following command:
fx cipd create -in <package-directory> -install-mode copy \
-name <package-name> \
-tag git_repository:<source-git-repositry> \
-tag git_revision:<source-git-revision>
package-name has the format fuchsia/firmware/<name>.
<name> should be a string that identifies the firmware. It may contain
any non-whitespace character. It is helpful to identify the driver that will
use the firmware in the name.
After this step, the package is uploaded to CIPD. Check the
CIPD browser here
for packages under fuchsia/firmware.
Adding the Firmware Package to the Build
Add the following entry in prebuilt/zircon.ensure:
Where <name>, <package-name> and <source-git-revision> matches the
values passed to cipd create above. The package will be downloaded to
the path specified by @Subdir under prebuilt, i.e.
prebuilt/firmware/<name>.
Next, update prebuilt/zircon.versions with the following command:
Upload this change to Gerrit and send it to the CQ. The firmware package will
be downloaded by scripts/download-prebuilt along with the toolchain and QEMU.
Using the Firmware Package in the Driver
Add the following line to the driver's rules.mk:
This will install the firmware to bootfs under
/boot/lib/firmware/$(basename $(MODULE_FIRMWARE)).
The load_firmware() API, defined in driver.h
loads the firmware pointed to by the path in a VMO.