I'm reversing the BIOS of my laptop, for fun and for learning something new.
Inside it, I just stepped into this piece of code:
mov ecx, 13Ah
and eax, 1
Looking on the Intel datasheet "Intel 64 and IA-32 Architectures Software Developer’s Manual", I couldn't find any clue about it, but seems like that in this BIOS release, its value is essential the determine if a key feature such as 'cache as RAM' have to be initialized using an approach or another.
I checked also on the AMD equivalent datasheet, even though I'm sure the MotherBoard is only for Intel CPUs.
Does anyone indicate me an alternative source(s) where to search what this 0x13a register does?