Re: [Xen-devel] [ARM] SMMU and PCI passthrough Was: Re: Xen 4.5-rc1 update (RC1 is out 2014-Oct-24th)

[Julien Grall <julien.grall@xxxxxxxxxx>]

On 03/11/2014 05:08, manish jaggi wrote:
> On 2 November 2014 15:47, Julien Grall <julien.grall@xxxxxxxxxx> wrote:
> > (Renaming the subject of the thread).
> >
> > On 02/11/2014 06:03, manish jaggi wrote:
> > > On 1 November 2014 23:13, Julien Grall <julien.grall@xxxxxxxxxx> wrote:
> > > > Hi Konrad,
> > > >
> > > >
> > > > On 31/10/2014 21:01, Konrad Rzeszutek Wilk wrote:
> > > > > On Fri, Oct 31, 2014 at 02:31:41PM +0000, Julien Grall wrote:
> > > > > > On 10/31/2014 02:24 PM, Konrad Rzeszutek Wilk wrote:
> > > > > > > > > *  PVH - PCI passthrough for DomU.
> > > > > > > >
> > > > > > > > I am working on Cavium Thunder (ARM64) on this feature.
> > > > > > > > [Xen SMMU driver changes + PCI passthrough changes in Xen and Linux]
> > > > > >
> > > > > >
> > > > > > FYI, I'm currently reworking the SMMU drivers to resync with Linux.
> > > > > > With
> > > > > > thoses changes, you should not need to modify the SMMU code.
> > > > >
> > > > >
> > > > > Thank you for the update. Put your name behind that for 4.6.
> > > > > > > Ok, replaced Julien's name with yours. Please make sure
> > > > > > > that for the Linux patches you CC xen-devel and the
> > > > > > > maintainers (David, Stefano, Boris and me).
> > > > > >
> > > > > >
> > > > > > There is 2 distinct passthrough: platform (i.e non-PCI) and PCI one.
> > > > > >
> > > > > > While Manish is working on PCI passthrough, I'm still working the
> > > > > > non-PCI one. Please don't drop my name.
> > > > >
> > > > >
> > > > > I thought that Arianna's patches had taken care of that (the MMIO
> > > > > part?). Or does each platform need a different implementation of
> > > > > that?
> > > >
> > > >
> > > > To passthrough a platform device you need to be able to assign the device
> > > > to
> > > > the guest via the IOMMU and map MMIOs (done by Arianna's series) and
> > > > interrupts.
> > > For a PCI passthrough SMMU ops are to be added. The way the smmu for a
> > > pci device is found needs to be updated in the smmu.c, so there are
> > > some substantial changes to smmu.c for pci passthrough.
> >
> > The SMMU drivers in Linux already supports PCI. As I'm currently resync our
> > driver with this version PCI assignment in the SMMU should come freely.
> >
> > I expect the only plumbing for the Xen callback and few bugs fixes will be
> > necessary.
> we can discuss more on design level. There are changes
What kind of changes? Do you have a tree with them?

> > > Also MMIO mapping code the same pci device to be added.
> >
> > Hmmm? What do you mean? MMIO mapping code is definitely not part of the SMMU
> > drivers.
> >
> > IIRC, this should be done by either the toolstack or PCI back in Linux.
> >
> > > So in short there changes, and as they are in the same files and
> > > features are also similar,  is it possible that we work together may
> > > be julien can provide a design document (simple txt file would do).
> >
> > There is no need of design document for the SMMU drivers. Everything for DT
> > passthrough is already there.
> It would be helpful if you can provide a basic flow.
http://lists.xen.org/archives/html/xen-devel/2014-07/msg04090.html

--
Julien Grall

_______________________________________________
Xen-devel mailing list
Xen-devel@xxxxxxxxxxxxx
http://lists.xen.org/xen-devel