[Skiboot] [PATCH v2] phb4: Initialization sequence updates

[Russell Currey]

On Wed, 2017-07-19 at 16:00 +1000, Michael Neuling wrote:
> > +	if (p->rev == PHB4_REV_NIMBUS_DD10) /* XXX CAPI has diff. value */
> > +		out_be64(p->regs + 0x0db0,	0xfbffd703fe7fbf8full);
> > +	else
> > +		out_be64(p->regs + 0x0db0,	0x3bffd703fe7fbf8full);
> 
> So we are still debating if this is correct? right?

It's right according to spec, but it's a bad idea that prevents us from booting.
 Essentially this makes two errors fatal because without them there could be
MMIO data integrity issues,  but these errors trigger when reading things that
aren't there, and it turns out you need to do a lot of that when probing.

I'll do some more testing and send a v3 without this hunk.  The consequences are
that MMIOs on DD1 are sometimes sketchy, with no workaround.

- Russell

> 
> mikey