On Wed, Jun 27, 2018 at 11:38:17AM +1000, Benjamin Herrenschmidt wrote:
> On Wed, 2018-06-27 at 03:35 +0300, Michael S. Tsirkin wrote:
> >
> > > +
> > > +/* Extract field fname from val */
> > > +#define GETFIELD(fname, val) \
> > > + (((val) & fname##_MASK) >> fname##_LSH)
> > > +
> > > +/* Set field fname of oval to fval
> > > + * NOTE: oval isn't modified, the combined result is returned
> > > + */
> > > +#define SETFIELD(fname, oval, fval) \
> > > + (((oval) & ~fname##_MASK) | \
> > > + ((((typeof(oval))(fval)) << fname##_LSH) & fname##_MASK))
> > > +
> >
> > Pls don't make up macros like these. We can't have each device do it.
>
> So what ? We move the macros in a generic place ? These are MUCH better
> than open-coding the masks & shifts and much less error prone.
include/qemu/bitops.h has a ton of handy macros.
> > > @@ -1031,6 +1110,7 @@ static Property pnv_chip_properties[] = {
> > > DEFINE_PROP_UINT64("ram-size", PnvChip, ram_size, 0),
> > > DEFINE_PROP_UINT32("nr-cores", PnvChip, nr_cores, 1),
> > > DEFINE_PROP_UINT64("cores-mask", PnvChip, cores_mask, 0x0),
> > > + DEFINE_PROP_UINT32("num-phbs", PnvChip, num_phbs, 1),
> > > DEFINE_PROP_END_OF_LIST(),
> > > };
> >
> > How about instanciating each extra phb using -device?
> > Seems better than teaching everyone about platform-specific
> > options.
>
> It's about which PHBs are enabled, not which are instanciated, if I
> understand Cedric changes ...
>
> This aims are implementing the POWER8 chip correctly, it has a fixed
> number of PHBs per-chip at very specific XSCOM addresses, that the
> firwmare knows about.
>
> Cheers,
> Ben.
