745x coherency fix for 2.4?

[Mikael Pettersson]

Benjamin Herrenschmidt writes:
 > >  
 > > -#ifdef CONFIG_SMP
 > > -	if ((flags & _PAGE_NO_CACHE) == 0)
 > > +	if (((flags & _PAGE_NO_CACHE) == 0) &&
 > > +	    (cur_cpu_spec[0]->cpu_features & CPU_FTR_NEED_COHERENT))
 > >  		flags |= _PAGE_COHERENT;
 > > -#endif
 > 
 > Wouldn't your patch result in _not_ setting _PAGE_COHERENT on non-broken
 > CPUs when CONFIG_SMP is set ?

The cputable.c change adds CPU_FTR_NEED_COHERENT to all CPUs when
CONFIG_SMP is set. That's why the changes from #ifdef CONFIG_SMP
to checking this feature flag work for both SMP and 745x.

The logic is straight from the 2.6 kernel; I only adapted it where
the 2.4 kernel was different, like some of the cputable entries
were missing in 2.4.

/Mikael