Re: [PATCH v6 2/7] xen/arm: add pci-domain for disabled devices

[Julien Grall <julien@xxxxxxx>]

Hi Oleksandr,

On 23/11/2021 06:31, Oleksandr Andrushchenko wrote:
> On 22.11.21 19:17, Julien Grall wrote:
> > Hi,
> >
> > On 22/11/2021 16:23, Oleksandr Andrushchenko wrote:
> > > On 22.11.21 17:29, Julien Grall wrote:
> > > > I would prefer to go with my way. This can be refined in the future if we find 
> > > > Device-Tree that matches what you wrote.
> > > Ok, so just to make it clear:
> > >    >a PCI device would always be described as a child of the hostbridges. So I would rework the 'if' to also check 
> > > if the parent type is not "pci"
> > That's correct. Thank you!
> Ok, so how about
>       if ( is_pci_passthrough_enabled() && dt_device_type_is_equal(node, "pci") 
> )
>       {
>           bool skip = false;
>
>           /*
>            * If the parent is also a "pci" device, then "linux,pci-domain"
>            * should already be there, so nothing to do then.
>            */
This comment is a bit confusing. I think what matter if the parent is a 
"pci" device, then the current node must not be a hostbridge. So we can 
skip it. However...
>           if ( node->parent && dt_device_type_is_equal(node->parent, "pci") )
>               skip = true;
>
>           if ( !skip && !dt_find_property(node, "linux,pci-domain", NULL) )
>           {
> I played with a single if and it looks scary...
... how about introducing an helper that will return true if this node 
is likely an hostbridge?
Cheers,

--
Julien Grall