Re: Design doc of adding ACPI support for arm64 on Xen - version 2

[Ian Campbell <ian.campbell@citrix.com>]

On Tue, 2015-08-11 at 15:19 +0100, Ian Campbell wrote:
> On Fri, 2015-08-07 at 10:11 +0800, Shannon Zhao wrote:
> > This document is going to explain the design details of Xen booting 
> > with
> > ACPI on ARM. Maybe parts of it may not be appropriate. Any comments are
> > welcome.
> 
> Some small subsets of this seem like they might overlap with what will be
> required for PVH on x86 (a new x86 guest mode not dissimilar to the sole
> ARM guest mode). If so then it would be preferable IMHO if PVH x86 could
> use the same interfaces.
> 
> I've trimmed the quotes to just those bits and CCd some of the PVH people
> (Boris and Roger[0]) in case they have any thoughts.
> 
> Actually, having done the trimming there is only one such bit:
> 
> [...]
> > 4. Map MMIO regions
> > -------------------
> > Register a bus_notifier for platform and amba bus in Linux.

Previously PCI was included in this scheme, which is why I thought of PVH,
having missed that PCI wasn't mentioned here now.

Is it handled some other way now or is that just an accidental omission?

> >  Add a new
> > XENMAPSPACE "XENMAPSPACE_dev_mmio". Within the register, check if the
> > device is newly added, then call hypercall XENMEM_add_to_physmap to map
> > the mmio regions.
> 
> Ian.
> 
> [0] Roger is away for a week or so, but I'm expect feedback to be of the
> "we could use one extra field" type rather than "this needs to be done 
> some
> totally different way for x86/PVH" (in which case we wouldn't want to 
> share
> the interface anyway I suppose) so need to block on awaiting that 
> feedback.