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 chip, in PowerPC systems. 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. -- Hollis Blanchard IBM Linux Technology Center ------------------------------------------------------------------------- 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
