On Thu, Aug 30, 2018 at 7:55 PM Sunil Kovvuri <sunil.kovv...@gmail.com> wrote: > On Thu, Aug 30, 2018 at 7:37 PM Arnd Bergmann <a...@arndb.de> wrote: > > On Tue, Aug 28, 2018 at 3:10 PM Sunil Kovvuri <sunil.kovv...@gmail.com> > > wrote: > > Ok, I think I understand the PF/VF distinction now. One (to me) > > surprising aspect here is that you not just have one physical function > > that you can use to assign resources to multiple virtual functions, > > but also a second level of virtualization that is used to assign > > resources to "physical functions" that are less physical than the > > name suggests. > > Yes, PF is just for name sake, on-boot there is no difference between > PFs/VFs as such. > PF0 has privilege access to assign resources to all PFs and their VFs. > This admin function driver loads for PF0.
ok > > The part that I have not grasped yet is what the split between > > the CGX and the AF is for, how they relate to one another, and > > what the software abstraction for the two is going to be. > > In HW, CGX is a separate PCI device which handles the serdes and > physical ethernet interface. > Ethernet driver in drivers/net/ethernet can only communicate to > admin function driver since they share a mailbox memory. > So we had to bind both CGX and admin function drivers to almost work as one, > inorder to provide relavent info to ethernet drivers. That's why we > have many functions > from CGX driver which AF uses. > > eg: Firmware gets to know about a physical interface status change, > which CGX driver gets > to know and it uses AF's mailbox communication to inform ethernet > driver about the event. Would it make sense then to combine the CGX driver and the AF driver into a single module? It sounds like you can never really use one without the other anyway, and that would make it easier to have a sensible abstraction to user space. Arnd