At Fri, 22 Aug 2008 16:36:22 +0200, Thomas Bogendoerfer wrote: > > On Fri, Aug 22, 2008 at 12:23:48PM +0200, Takashi Iwai wrote: > > unsigned long prot = pgprot_val(_prot) & ~_CACHE_MASK; > > #ifdef CONFIG_SGI_IP32 > > #ifdef CONFIG_CPU_R10000 > > prot = prot | _CACHE_UNCACHED_ACCELERATED; > > #else > > prot = prot | _CACHE_CACHABLE_NO_WA; > > #endif > > #else > > prot = prot | _CACHE_UNCACHED; > > #endif > > return __pgprot(prot); > > this won't work for recording channels on IP32, because the write trough > mapping will hide updates done via DMA. Hmm, not so easy... > I'd start with just > > prot |= _CACHE_UNCACHED > > and if some MIPS system needs more specific treatment, we just add > that later. OK, then it's essentially pgprog_noncached() as in my second patch. Thanks! Takashi