On Mon, 2008-01-28 at 10:23 -0600, Olof Johansson wrote: > Ok, makes sense. > > I was going to protest the hack for >32GB configs, with the motivation > that just using the htab-backed window is way too small for such a > config. However, with 32GB memory and 4K pages, that window is 512MB, so > we should be fine.
Might be a problem with 64K pages tho... Or do we use the same calculation ? In addition, on those blades, really the only device that is limited to 32 bits (and thus is forced to use the iommu remapped region) is USB. > Having that described in the patch (or at least in the patch description) > to make it more clear could be good. That, and the fact that the mapping > is offset on <32GB memory machines, and thus not really a 1:1 mapping. Should be called a "linear" mapping. > Does the cell I/O bridge reflect out accesses to 2-4GB on the bus > again? If not, that could be another place to stick the dynamic range > for large config machines. On the PCI bus itself, 2-4GB is where MMIO sits. Ben. _______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@ozlabs.org https://ozlabs.org/mailman/listinfo/linuxppc-dev
