What you’ll actually see documented through the series itself is amd64-specific, but that’s only due to time constraints. All the same principles apply for other architectures: I’ve tested this series for the arm64 DragonBoard 410c, and have included it as reference information. Thank you for speaking up-- I’ll make sure I do the same for the rpi2/3.
Please follow along with the rest of the series, and if at the end you don’t quite understand what you need to do to apply it to ARM targets, I’d be happy to add a 6th part to the series devoted to discussing other architectures.