Cool point I've only tried it with basic fetches where it worked (using this BFAR reg) - but not with actual code execution. I hope to soon have time to look more into it and then I will definitely try such instructions and write back. However, the datasheet does suggest it should be possible... but their wording is "This may be used to transparently decrypt data on-demand from external flash" (my emph)... so perhaps they really only meant this for data, not for instruction execution! That or they were thinking of a different trapping mechanism that is more restartable? Or perhaps bus faults are somehow always restartable in this context (the prefetch errors appear as bus faults at the right time, the pipelined effects are rolled back etc.).
Statistics: Posted by martinxx — Wed Oct 15, 2025 7:46 pm