Hollis Blanchard wrote: > On Tue, 2007-12-04 at 12:39 +0800, Zhang, Xiantao wrote: >> Hollis Blanchard wrote: >>> Actually, (now that I try to build with it :) this doesn't work for >>> PowerPC, which defines (or rather, doesn't not define) >>> CONFIG_HAS_IOPORT. >> >> You mean ppc has ioport , but you don't use current kvm io >> infrastructure to handle it ? > > It's a matter of perspective. :) > > The PowerPC architecture has no "IO" instructions; therefore all IO > accesses are MMIO. > However, you can place devices with IO ports in a PowerPC system. In > this case, the bridges are configured to translate MMIO accesses > coming from the processor into IO port accesses on the bus. It is > quite common to find standard x86 ISA devices, such as a SuperIO
Thank you for your elaboration. So, bridge emulation in qemu will take over the responsibility of the translation for ppc? > In Linux, CONFIG_HAS_IOPORT doesn't really mean "does the architecture > use IO ports," which is what I thought it meant. Instead, it means > "should we track IO resources as well as MMIO resources," and that's > true on PowerPC because we need manage the ISA bus as mentioned above. > (The only current user of the symbol is lib/devres.c.) > > In summary, it's an inappropriate ifdef for this situation. Agree. ------------------------------------------------------------------------- SF.Net email is sponsored by: The Future of Linux Business White Paper from Novell. From the desktop to the data center, Linux is going mainstream. Let it simplify your IT future. http://altfarm.mediaplex.com/ad/ck/8857-50307-18918-4 _______________________________________________ kvm-devel mailing list kvm-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/kvm-devel
