On Thu, Jun 23, 2005 at 12:01:57PM +0100, Maciej W. Rozycki wrote: > Well, the flag is not really to specify whether the common code is to be > used or not. It's about whether the TLB is like that of the R4k. > Actually it's always been a mystery for me why the common code cannot be > used for the SB1, but perhaps there is something specific that I could > only discover in that "SB-1 Core User Manual" that I yet have to see, > sigh... > > Of course if your TLB is indeed different from that of the R4k, then you > shouldn't be setting cp0.config.mt to 1 in the first place... The reason was primarily the tiny bit of extra performance because the SB1 doesn't need the hazard handling overhead. Also tlb-sb1 has a few changes that are needed to initialize a TLB in undefined state after powerup. That was needed to run Linux on firmware-less SB1 cores. Ralf
