Qualcomm DSP binaries

While linux-firmware contains firmware for the DSPs present on the devices using Qualcomm SoCs, using the FastRPC interfaces, compressed audio support or getting the sensors data on those devices requires additional set of binaries to be executed on the DSP side.

These binaries include fastrpc_shell_N (where N is 0, 1, 2, 3), fastrpc_shell_unsigned_N (N = 3, special version of shell for CDSP only), libraries implementing necessary hooks, etc.

This repo provides a central repository for handling these files.

Design decisions

These binary files are tied to the particular SoC and DSP firmware revision. As such it is impossible to provide a single set of binaries that works for all the targets. Moreover, different versions of linux-firmware require corresponding set of binaries.

For this reason this repo includes all binaries at the same time. The exact set to be installed is selected via the config.txt file present in the repo. This provides flexibility to users, while still allowing trunk revision to track the top of the tree of the linux-firmware repo.

Data origin

WHENCE file documents orignal locations for the tarballs with the library files.

Maintainer workflow

Adding new binaries

1. Place the new binary directory under the appropriate SoC path (e.g. qcs6490/Thundercomm/RubikPi3/<version>/).
2. Add a corresponding Dir: block to WHENCE, including Licence: and Status: fields.
3. Add an Install: line to config.txt referencing the new path.
4. Run make check to validate the new entries.

Validating against an installed linux-firmware tree

To verify that the version strings declared in config.txt match those embedded in the actual binaries:

./scripts/checkfw.py <path-to-linux-firmware>

Cutting a release

./scripts/release.sh <tag>

This will run make check, create a signed git tag, produce a tarball under dist/, and sign it with GPG.