alt Hacker NewsHonestly feels like a misdesign in ARM. Where does it ever make sense for Device memory to not be data prefetchable, but allow instruction prefetch? It should IMHO disable all prefetch…
Honestly feels like a misdesign in ARM. Where does it ever make sense for Device memory to not be data prefetchable, but allow instruction prefetch? It should IMHO disable all prefetch…
(Total guess) this feels like an attempt at restricting what parts of the hardware pipeline need to know what; if prefetches need to key off of both the device bit and the nx bit, then both of those need to be piped into the frontend, whereas if device is only relevant for data prefetches then only the nx bit needs to be available there (while device would be piped into the backend where the data prefetcher lives).