On Wednesday, March 16, 2005 10:35 am, Keir Fraser wrote: > On 16 Mar 2005, at 18:10, Christoph Hellwig wrote: > > On Wed, Mar 16, 2005 at 10:01:07AM -0500, Rik van Riel wrote: > >> In the case of AGP, the AGPGART effectively _is_ the > >> IOMMU. Calculating the addresses right for programming > >> the AGPGART is probably worth fixing. > > > > Well, it's a half-assed one. And some systems have a real one. > > > > But the real problem is that virt_to_bus doesn't exist at all > > on architectures like ppc64, and this patch touches files like > > generic.c and backend.c that aren't PC-specific. So you > > effectively break agp support for them. > > The AGP driver is only configurable for ppc32, alpha, x86, x86_64 and > ia64, all of which have virt_to_bus.
Yeah, but that doesn't mean it makes sense on all those platforms. The biggest problem with virt_to_bus (well, depending on who you talk to) is that it can't handle systems where the address translation must be done differently depending on *which* bus we're getting a bus address for. Not sure what makes sense in this case though... is the DMA mapping interface appropriate? Jesse - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
