AMD ICE/Debug-mode code?

[VirtualLarry]

Does anyone recall the 32-bit hex code that got leaked some time ago, that enabled their super-secret debug / ICE - In-Circuit Emulator functionality?

It was basically like a "God-mode" code for their CPUs. I'm not even sure what all was possible with it, but it was meant for debugging the actual CPU I believe, so it enabled a lot of functionality.

 

[CTho9305]

You're looking for undocumented AMD MSRs? Did anyone ever come up with a use for them?

 

[TerryMathews]

It's over my head but http://hardware.slashdot.org/story/10/11/12/047243/hidden-debug-mode-found-in-amd-processors