Heater, Daniel (GE Infrastructure) wrote: >>I don't know about x86 bus organization, but maybe it limits >>the address >>range for available addresses too strongly (on a single bus, >>where the >>Universe is on). Comparing how much window space you can map with the >>old version and the new one on x86 could prove useful. >> >> > >Your dead on right. I cannot allocate as much space. In fact, >on a VMIVME-7750 I'm only able to allocate 768KB now vs. the >~2MB I could access before. > > Since we only request the current bus the Universe is on, there could be a fix: We could iterate the PCI bus tree to the top (there is some parent bus field, IIRC), and then start complete iteration until a suitable resource is found. This may produce larger resource regions with reasonable effort.
Are you sure you mean 768 _KB_ and 2 _MB_, not 768 _MB_ and 2 _GB_? My SLSI window is already 64 MB big, and with the PCI layout on my MVME2100 it is imaginable that I could map 84000000 - BEFFFFFF = 944MB (from end of SLSI window to start of the Universe I/O memory)? With kind regards, Oliver Korpilla ** Sent via the linuxppc-embedded mail list. See http://lists.linuxppc.org/
