Alan Cox writes: > On Iau, 2005-03-17 at 09:34, Paul Mackerras wrote: > > This code needs real physical addresses, which are not the same things > > as bus addresses. > > Not always. The code needs platform specific goodies. We've only never > been burned so far because there isn't a box with an IOMMU and AGPGART > where one maps through the other.
That sounds like a good way to make AGP accesses slower. :) Seriously, given that AGP is a technology that is being superseded by PCI Express, I think it's reasonable to look at the range of current implementations to see what we have to cope with. So I don't think it's worth worrying too much about the possibility of GARTs that go through the IOMMU. However, the idea of having phys_to_agp/agp_to_phys (or virt_to_agp/agp_to_virt) sounds like it wouldn't be too much effort, if it would help Xen. Paul. - 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/
