Yea, this was the horrible world of embedded programming and working with SoCs before the iPhone SDK finally raised the bar. BSPs composed of barely-working cobbled-together gcc toolchains, jurassic-aged kernels, opaque blobs for flashing the devices, incomplete or nonworking boot loaders, entirely different glue scripts for every tiny chip rev, incomplete documentation. And if you wanted to build your own toolchain? LOL, good luck because every gnu tool needed to be patched in order to work. It was a total mess. You could tell these companies just made chips and reference systems, and only grudgingly provided a way to develop on them. iPhone and Xcode was such breath of fresh air. It pulled me out of embedded and I never went back.
Modern ARM microcontrollers apparently use standard GNU toolchains shipped by my Linux distribution. Developing software for a Cortex M0+ was a really good experience. Lack of a complete device emulator made it hard to debug at times but I dealt with it.
Stop! You're giving me flashbacks of developing for Hypercom point of sale devices! Never again will I work with alpha software so buggy it only worked from bundled samples! One had to remove their widgets from a sample, one at a time, testing at each step, then adding your own one at a time. Otherwise it would break something and you'd have to start over.