Hi Simon, > So I wonder how best to move this forward so that we can build things > using binman and everything works?
It's still not ready yet, but I'm working on porting U-Boot SPL to some Amlogic SoCs [1]. I'm currently working on Amlogic S905 boards, but eventually I'll work on Amlogic S905X devices too. And speaking of signing, Jonas Karlman wrote amlimage, and integrated it into mkimage, and I applied his patch to my tree. There's a few things to be aware of about Amlogic signing and binaries in general, however. amlimage was intended for use with U-Boot SPL, which obviously has no support for Amlogic's FIP format and as such amlimage will only do as little as possible to get the bootROM to load U-Boot SPL. Most of the packaging format is handled by BL2. The fact that the signing process is completly different across SoC generations makes it difficult to implement them all into one single tool (and by which I mean all of it, not just signing BL2 for the bootROM to run it, that's mostly the same across SoCs). amlimage has been confirmed to work on GXBB (ODROID-C2 and the KII Pro set-top box), GXL (librecomputer lepotato), and SM1 (ODROID-C4). My U-Boot SPL port is still rather incomplete. As of today, it still can't boot anything from any storage device. The goal eventually is to be able to load upstream TF-A BL31 and U-Boot+linux. While Amlogic distributes proprietary BL31 binaries upstream Trusted Firmware-A has a port for some Amlogic SoCs [2], but as far as I know SM1 (which is the SoC generation your ODROID-C4 is using) is still unsupported. GXBB, GXL, AXG, and G12A are all supported however, but the overall port still lacks some features the proprietary implementation has. As for the SCP firmware (aka. BL30) I'm not aware of any reverse-engineering efforts for that. Honestly, in my opinion, including proprietary and poorly-written Amlogic utilities lacking a proper license, into U-Boot looks like a bad idea. [1]: https://git.vitali64.duckdns.org/misc/u-boot-kii-pro.git/log/?h=wip/spl [2]: https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git/tree/plat/amlogic Cheers.