On Sat, 25 Jun 2005, Thomas Bogendoerfer wrote:
> > > Subject: [patch] blast_scache nop for sc cpus without scache
> > Interesting. Which system needs this patch?
> RM400; looks like the secondary cache on the cpu module isn't normally
> attached, but like the board caches on den Indy. CONF_SC isn't set
> in cp0 config, but the cpu is an R4400SC -> crash in r4k_scache_blast*.
Are you sure CONF_SC isn't set? That would be weird, it's one of the
boot-mode settings so it would be hard to get it wrong. What's printed
upon bootstrap about caches?
Anyway these days we apparently ignore the result of the S-cache probe
and the sc_present variable. The only values that determine whether an
S-cache is present or not are: cpu_has_dc_aliases, cpu_has_ic_fills_f_dc
and cpu_has_subset_pcaches which you need to get right for your
configuration -- I guess cpu_has_dc_aliases == 0, cpu_has_ic_fills_f_dc ==
1 and cpu_has_subset_pcaches == 0 should be right to fulfil your needs
(but it may break elsewhere). Have I heard: "serious brain damage" from
you? Well, I couldn't agree more...