[PATCH 2/2] docs: Improve zPCI section in pci-addresses.rst

[Cornelia Huck]

On Fri, 17 Apr 2020 13:29:43 +0200
Boris Fiuczynski <fiuczy at linux.ibm.com> wrote:

> On 4/17/20 11:02 AM, Cornelia Huck wrote:
> > On Fri, 17 Apr 2020 10:50:02 +0200
> > Boris Fiuczynski <fiuczy at linux.ibm.com> wrote:
> >   
> >> On 4/16/20 6:14 PM, Cornelia Huck wrote:  
> >>> On Thu, 16 Apr 2020 17:56:18 +0200
> >>> Boris Fiuczynski <fiuczy at linux.ibm.com> wrote:
> >>>      
> >>>> Improving the zPCI example by choosing more distinct values and
> >>>> adding explanation for fid.
> >>>>
> >>>> Signed-off-by: Boris Fiuczynski <fiuczy at linux.ibm.com>
> >>>> ---
> >>>>    docs/pci-addresses.rst | 15 ++++++++-------
> >>>>    1 file changed, 8 insertions(+), 7 deletions(-)
> >>>>
> >>>> diff --git a/docs/pci-addresses.rst b/docs/pci-addresses.rst
> >>>> index 7c8e9edd73..4492389da5 100644
> >>>> --- a/docs/pci-addresses.rst
> >>>> +++ b/docs/pci-addresses.rst
> >>>> @@ -176,14 +176,14 @@ In the simplest case, the following XML snippet
> >>>>        <model name='pci-bridge'/>
> >>>>        <target chassisNr='1'/>
> >>>>        <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x0'>
> >>>> -      <zpci uid='0x0002' fid='0x00000001'/>
> >>>> +      <zpci uid='0x0001' fid='0x00000000'/>  
> >>>
> >>> Why this change? The pci-bridge does not show up in the guest anyway.  
> >> My assumption was that uid and fid for this would be autogenerated.
> >> Since uid 0x0001 and fid 0x00000000 have been freed up due to the change
> >> below this would be the autogenerated set.  
> > 
> > If that makes the XML look saner, no objection.
> >   
> >>  
> >>>      
> >>>>        </address>
> >>>>      </controller>
> >>>>      <interface type='bridge'>
> >>>>        <source bridge='virbr0'/>
> >>>>        <model type='virtio'/>
> >>>>        <address type='pci' domain='0x0000' bus='0x01' slot='0x01' function='0x0'>
> >>>> -      <zpci uid='0x0001' fid='0x00000000'/>
> >>>> +      <zpci uid='0x0007' fid='0x00000003'/>
> >>>>        </address>
> >>>>      </interface>
> >>>>    
> >>>> @@ -191,21 +191,22 @@ will result in the following in a Linux guest:
> >>>>    
> >>>>    ::
> >>>>    
> >>>> -  0001:00:00.0 Ethernet controller: Red Hat, Inc. Virtio network device
> >>>> +  0007:00:00.0 Ethernet controller: Red Hat, Inc. Virtio network device
> >>>>    
> >>>>    Note that the PCI bridge is not visible in the guest; s390x always has a flat
> >>>> -topology.
> >>>> +topology. Also ``fid`` does not define slot or function of the PCI address.  
> >>>
> >>> I find the sentence regarding 'fid' confusing. Maybe instead move up
> >>> the explanation from below regarding uid and fid?
> >>>
> >>> "The PCI address in the guest is generated from..."
> >>>      
> >> Lets join your proposal with Andreas and move his rewrite up to here.
> >> Like:
> >> ...topology.
> >> The PCI address in the guest is generated from the information provided
> >> via the ``zpci`` element: more specifically, ``uid`` is used as the PCI
> >> domain.``fid`` doesn't appear in the PCI address itself, but it will be
> >> used in sysfs (``/sys/bus/pci/slots/$fid/...``).  
> > 
> > Sounds good.
> > 
> > (Also the rest of the changes.)
> >   
> Before I break the r-b chain as well... Is that your r-b? :)
> 
> 

I'll add my R-b to a final patch :)