Re: [Qemu-devel] [qemu-s390x] [PATCH v2 10/10] s390x/cpumodel: wire up 8561 and 8562 as gen15 machines

[Cornelia Huck <cohuck@redhat.com>]

On Mon, 29 Apr 2019 09:51:39 +0200
Christian Borntraeger <borntraeger@de.ibm.com> wrote:

> On 26.04.19 14:55, Cornelia Huck wrote:
> > On Fri, 26 Apr 2019 14:05:30 +0200
> > David Hildenbrand <david@redhat.com> wrote:
> >   
> >> On 26.04.19 14:01, Christian Borntraeger wrote:  
> >>>
> >>>
> >>> On 26.04.19 13:52, David Hildenbrand wrote:    
> >>>> On 26.04.19 13:36, Christian Borntraeger wrote:    
> >>>>>
> >>>>>
> >>>>> On 26.04.19 13:32, David Hildenbrand wrote:    
> >>>>>> On 26.04.19 13:10, Christian Borntraeger wrote:    
> >>>>>>> 8561 and 8562 will be gen15 machines. There is no name yet, lets us use
> >>>>>>> the cpu id as base name. Later on we can provide aliases with the proper
> >>>>>>> name.
> >>>>>>>
> >>>>>>> Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
> >>>>>>> ---
> >>>>>>>  target/s390x/cpu_models.c | 2 ++
> >>>>>>>  1 file changed, 2 insertions(+)
> >>>>>>>
> >>>>>>> diff --git a/target/s390x/cpu_models.c b/target/s390x/cpu_models.c
> >>>>>>> index d683635eb5..dd6415103f 100644
> >>>>>>> --- a/target/s390x/cpu_models.c
> >>>>>>> +++ b/target/s390x/cpu_models.c
> >>>>>>> @@ -83,6 +83,8 @@ static S390CPUDef s390_cpu_defs[] = {
> >>>>>>>      CPUDEF_INIT(0x3906, 14, 1, 47, 0x08000000U, "z14", "IBM z14 GA1"),
> >>>>>>>      CPUDEF_INIT(0x3906, 14, 2, 47, 0x08000000U, "z14.2", "IBM z14 GA2"),
> >>>>>>>      CPUDEF_INIT(0x3907, 14, 1, 47, 0x08000000U, "z14ZR1", "IBM z14 Model ZR1 GA1"),
> >>>>>>> +    CPUDEF_INIT(0x8561, 15, 1, 47, 0x08000000U, "8561", "IBM 8561 GA1"),
> >>>>>>> +    CPUDEF_INIT(0x8562, 15, 1, 47, 0x08000000U, "8562", "IBM 8562 GA1"),
> >>>>>>>  };    
> >>>>>>
> >>>>>> Thinking out loud, I know that official names are not published yet.
> >>>>>> Looking at the recent history (z13, z14), my educated guess would be
> >>>>>> z15. I guess pretty much everybody would guess that.    
> >>>>>
> >>>>> Not sure about trademark aspects - especially if this really becomes z15. The smaller
> >>>>> machine has no real history (ZR1 vs. s vs BC). So I think I would rather have a correct
> >>>>> number than a partially correct name.    
> >>>>
> >>>> We could also use "gen15a" and "gen15b", still better to get than magic
> >>>> numbers. (yeah well, they are not magic)
> >>>>
> >>>> If you want to stick with numbers, be aware that cpu numbers are not
> >>>> injective, so at some point we will need e.g. "8561.2", just so you're
> >>>> aware of the implications.    
> >>>
> >>> I think whatever we have here is only used internally for expansion (host-model)
> >>> and the user will use later the real name when available. (custom). So probably this
> >>> does not matter for a long time. But I might be wrong.
> >>> I tend to prefer gen15 over z15 but 856x has also its charm.  
> > 
> > FWIW, I'd prefer gen15 over 856x, but...  
> 
> I actually think that the cpu id would be a nice name for expansion because it is
> guarenteed to stay and it is unique and it allows to have a different content (if
> that would be necessary) for 2 gen15 machines.
> >   
> >>>     
> >>
> >> Another question would be, can we rename before the next QEMU release,
> >> so it will never be officially part of QEMU? Then we don't need aliases
> >> after all. Of course, distros have to take care of that as well, but
> >> that shouldn't be upstream QEMUs business.  
> > 
> > ...if we could do that, I'd like that even better.  
> 
> I dont think that I know the name in time before the next release.
> So lets go with gen15a/gen15b or 8561/8562?

I always have trouble remembering number combinations, so I'd vote for
gen15a/gen15b if the official names are not an option.