[U-Boot] [PATCH] nds32: split common cache access from cpu into lib

[Marek Vasut]

Dear Mike Frysinger,

> On Thursday 19 July 2012 05:02:21 Marek Vasut wrote:
> > Dear Mike Frysinger,
> > 
> > > On Sunday 15 July 2012 04:12:45 Marek Vasut wrote:
> > > > Dear Macpaul Lin,
> > > > 
> > > > > +void flush_cache(unsigned long addr, unsigned long size)
> > > > > +{
> > > > > +	flush_dcache_range(addr, addr + size);
> > > > > +	invalidate_icache_range(addr, addr + size);
> > > > 
> > > > You probably want to flush dcache in here and that's it.
> > > 
> > > i don't think so ... i think that's what flush_dcache_range() is for.
> > > and our common/cmd_*.c files assume that flush_cache() will invalidate
> > > icache (see the bootm/load funcs that write executable content into
> > > memory and then flush the regions).
> > 
> > Than it's borked on arm926ejs too ... ?
> 
> if it doesn't flush icache in the flush_cache() function, then i would say
> so
> 
> sounds like we should rip all this cache stuff out of common.h and into
> like cache.h so we can document the API expectations.  i think Wolfgang
> was against this before, but maybe that was just creating a header for one
> specific cache macro and not all cache stuff ?

Certainly this sounds good. We'd also be able to add some nice instrumentation 
while at that, to detect problematic cases with DEBUG enabled or so. The cache 
stuff is starting to get really crazy.

Best regards,
Marek Vasut