Re: [Qemu-devel] questions about pci

[陳韋任 <chenwj@iis.sinica.edu.tw>]

> I read pci code in qemu about i440fx, pci.c and so on. I think if guest
> os whose mainboard is based on x86, it will use IO instructions to
> access PCI configuration space.If not use passthrough, qemu should
> emulate these operations.I find a function called kvm_handle_io who will
                                                    ^^^^^^^^^^^^^

  Looks suspicious. Prefix kvm mean passthrough, I guess.

> emulate ioport write/read, I have traced this function, but I haven't found it has
> any relationship with pci read/write configuration space functions like
> i440fx_write_config and piix3_write_config.So how does it emulate pci
> configuration space access when not use passthrough?

  `grep -r i440fx_write_config *` show you that you should take a look on
hw/piix_pci.c. Besides, setting breakpoint at i440fx_write_config also show you
how it get called.

HTH,
chenwj

-- 
Wei-Ren Chen (陳韋任)
Computer Systems Lab, Institute of Information Science,
Academia Sinica, Taiwan (R.O.C.)
Tel:886-2-2788-3799 #1667
Homepage: http://people.cs.nctu.edu.tw/~chenwj