On Tue, Apr 5, 2011 at 10:39 AM, Avi Kivity <a...@redhat.com> wrote: > On 04/04/2011 08:02 PM, Blue Swirl wrote: >> >> On Mon, Apr 4, 2011 at 7:35 PM, Avi Kivity<a...@redhat.com> wrote: >> > On 04/04/2011 07:22 PM, Anthony Liguori wrote: >> >> >> >> On 04/04/2011 10:59 AM, Michael S. Tsirkin wrote: >> >>> >> >>> On Mon, Apr 04, 2011 at 06:27:57PM +0300, Avi Kivity wrote: >> >>>> >> >>>> Many PCI BARs that use the memory address space map a single MMIO >> >>>> region >> >>>> into >> >>>> the entire BAR range. Introduce an API pci_register_bar_simple() >> >>>> for >> >>>> that use >> >>>> case, and convert all users where this can be done trivially. >> >>>> >> >>>> This will reduce the work required to introduce a PCI memory API; >> >>>> it's >> >>>> also >> >>>> a nice code reduction in its own right. >> >>> >> >>> This will save some code, so >> >>> Acked-by: Michael S. Tsirkin<m...@redhat.com> >> >>> >> >>> I really hope the rest of devices will follow. >> >> >> >> How complete is this? >> > >> > I converted all devices which were easy to convert. There may be one >> > or two >> > more that can be converted with additional work (and perhaps with an >> > additional pic_bar_get_current_address() API, and a >> > pci_bar_set_coalescing() >> > API). The rest likely need to stick with the callback-based API. >> >> In my version which I sent earlier but didn't commit, also other BARs >> besides the first one and also tricky devices like VGA were handled. >> >> But I didn't commit it because I felt it was not going to right >> direction. I think the BARs should be specified in PCIDeviceInfo >> instead of adding more function calls. The same applies to this patch >> set. > > The more complicated BARs cannot be described declaratively (at least > without a lot of complicated infrastructure). They can switch from RAM to > MMIO mappings at runtime, and have different sub-regions.
Subregions should be possible, but I agree run time switch will not. Those should be pretty rare, though.
