| # Firmware Development |
| |
| The firmware SDK provides definitions and reference code used to develop |
| firmware for Fuchsia devices. |
| |
| The eventual goal is to make this SDK contain everything needed for booting |
| into Fuchsia, so that all the firmware requirements can be met by porting the |
| SDK code to the device. At the moment though some libraries are not yet |
| included in the SDK so must be found elsewhere. |
| |
| ## Building the Firmware SDK |
| |
| The firmware SDK build rules live in `sdk/BUILD.gn`. The SDK is not built |
| in the normal flow, but can be built manually as follows: |
| |
| 1. Add `build_sdk_archives=true` to your gn args, typically either by one of: |
| |
| 1. `fx set ... --args=build_sdk_archives=true` |
| 2. `fx args` and add `build_sdk_archives = true` to the args file |
| |
| 1. Run `fx build sdk:firmware` |
| |
| 1. Find the resulting SDK archive at `<build_dir>/sdk/archive/firmware.tar.gz` |
| |
| ## Porting |
| |
| Firmware development is usually pretty device-specific so it's not expected |
| that this code will be usable directly; some porting work will be necessary. |
| Because of this, there's no API stability requirement - if a device uprevs to |
| a new firmware SDK, we expect to have to port again including adapting to any |
| API changes. |
| |
| However, to ease the porting burden, we do require that everything in the |
| firmare SDK has a pure C implementation available, as firmware toolchains are |
| commonly C-only. |
