Posted by wallaby13 on Feb 29, 2016; 6:29am
URL: https://itus.accessinnov.com/Shield-custom-build-environment-tp72p214.html

@Hans
like you say it looks like there is an SDK coming soon it looks like the SDK is for performance improovement which will be great but for now lets at least start by trying to mimic what we have got then move to making it better.

As for setting up a build environment i started with a ubuntu server base with lxdm (for the prittyness) and followed the build environment setup guide on the openwrt website(OpenWrt build system – Installation). The environment  allows me to select Octeon as the target operating system though as noted above not all Cavium Octeon processors will work with this target and we currently don't know if our processor is. This is going to be the bricking point.  I didn't delve into this target option too much last night as it was getting on midnight by the time i had everything running as i wanted but maybe we will have a direct CN7020 sub-target to get things compiled just right (i suspect we might have to work with the lgeneric Octeon though).

I note the cpu is at least partly based on a MIPS64 instruction set so tonight i plan to set up a vm environment using Qemu as it appears to be the only virtual i can get my hands on that will do MIPS64. By running the compiled image through x86 then MIPS64 i hope to be able to work out the majority of issues before we endanger any blue boxes. I suspect we might be able to port some of the scripts and code to some routers as well although they won't have a cpu designed for inspecting packets as well inside i guess. This is of course a little ways down the track.

I plan to attempt to run the current image in Qemu before trying a custom compile too.

@Roadrunnere42
Do you remember how you got your device working again. This could help figure out how to un-brick a device should we run into problems.

@everyone
This is going to be a slow and challenging task it is bigger than any of the kernel modding i have done before. I have no idea if we will even be successful but i hope it will be and want to make this work or something similar (like porting to another router).

Oh and i want dnscrypt too. I did a glance over the build system package inclusions while installing but didn't see it off the bat. It is probably still there but hidden away in a sub directory somewhere.