RE: [virtio-comment] [PATCH v9 0/4] admin: Access legacy registers using admin commands

[Parav Pandit <parav@nvidia.com>]

> From: Cornelia Huck <cohuck@redhat.com>
> Sent: Wednesday, July 5, 2023 9:43 AM

> 
> >> From: Michael S. Tsirkin <mst@redhat.com>
> >> Sent: Wednesday, July 5, 2023 7:09 AM
> >>
> >> OK I sent a bunch of comments. Pls try to address, unfortunately I
> >> didn't go in depth over the last patch, but I feel it should be
> >> squashed into the generic legacy command sections avoiding need for
> >> indirection, so rewriting it now wouldn't be efficient.
> >
> > I relooked at well yday.
> > Transport has very small section.
> > This aligns to how the existing spec is written, for example vq notify data is
> explained in generic way and defined in pci way in PCI chapter.
> > The indirection is fine and also self-contained similarly here.
> 
> Would it make sense to do this the other way around (i.e. use something that is
> PCI-only from the start?)
> 
> IIUC, the "legacy" problem as it stands is something specific to PCI, with MMIO
> using two distinct approaches for pre-1.0 and 1.0+, and CCW simply using
> different commands (and no need for any kind of cross
> access.) Not 100% sure about MMIO, but I don't think we need a version of this
> for CCW.
V4 or v5 was having everything in PCI and Michael asked to write as generic as possible.
so I moved large part as generic.
And kept pci part in pci.