Re:Ryzen Community Update #2
by RandomOpinion on Thursday March 30, 2017 @03:22PM
(#13998137)
Digging into the history briefly, patchable microcode seems to have existed in commercially released computers as far back as the 1960s.
"...CCROS [microcode] cards on the [IBM System/360] Model 30 could be replaced in the field. This made design modifications easier to accomplish, as well as providing for field diagnosis. ...
The later System/360 Model 25 and models of the later System/370 series were configured with at least one portion of the control store being read-write for loading microcode patches and microdiagnostics."
"...CCROS [microcode] cards on the [IBM System/360] Model 30 could be replaced in the field. This made design modifications easier to accomplish, as well as providing for field diagnosis. ...
The later System/360 Model 25 and models of the later System/370 series were configured with at least one portion of the control store being read-write for loading microcode patches and microdiagnostics."
https://people.cs.clemson.edu/~mark/uprog.html