Re: [Qemu-devel] [PATCH 4/4] hw/isa/i82378.c: use 1900 as a base year

[Artyom Tarasenko]

On Sun, Apr 14, 2019 at 7:01 PM Hervé Poussineau <address@hidden> wrote:
>
> Le 12/04/2019 à 23:06, Artyom Tarasenko a écrit :
> > AIX 5.1 expects the base year to be 1900. Adjust accordingly.
> >
> > Signed-off-by: Artyom Tarasenko <address@hidden>
> > ---
> >   hw/isa/i82378.c | 4 +++-
> >   1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/hw/isa/i82378.c b/hw/isa/i82378.c
> > index a5d67bc..546c928 100644
> > --- a/hw/isa/i82378.c
> > +++ b/hw/isa/i82378.c
> > @@ -107,7 +107,9 @@ static void i82378_realize(PCIDevice *pci, Error **errp)
> >       isa = isa_create_simple(isabus, "i82374");
> >
> >       /* timer */
> > -    isa_create_simple(isabus, TYPE_MC146818_RTC);
> > +    isa = isa_create(isabus, TYPE_MC146818_RTC);
> > +    qdev_prop_set_int32(DEVICE(isa), "base_year", 1900);
> > +    qdev_init_nofail(DEVICE(isa));
>
> I am not sure the base_year should be hardcoded in i82378. I can assume other 
> machines with a i82378 can have another base_year.

I doubt it to be honest. How would it work in the hardware? Is there a
pin which would switch a year?
I do believe the different i823xx may have the different base years though.

> Maybe you can you add a base_year property to i82378, and forward it to 
> mc146818 with object_property_add_alias?
> Then, change 40p machine to set it to 1900, without changing it for prep 
> machine.

Were you not going to drop the -M prep ? Because I sort of dropped the
support for it in OFW.
I had a branch were I added some registers to -M prep  enough that it
would be able to turn itself out as a PowerStack II Utah,
but then again I couldn't find any advantage of having two PReP machines.
AFAIK, the only OS which can run on Powerstack, but not on 40p is Motorola AIX.
But since we can have IBM AIX, I don't see why would we want to keep -M prep.

On the other hand, if you plan to revive it, I'll think about adding
the support for it to OFW.
PowerStack had a Cirrus VGA which we already have.

> >   }
> >
> >   static void i82378_init(Object *obj)
> >
>
> Hervé



-- 
Regards,
Artyom Tarasenko

SPARC and PPC PReP under qemu blog: http://tyom.blogspot.com/search/label/qemu