[Skiboot] [PATCH v4] platform: add Raptor Blackbird support

[Oliver O'Halloran]

On Thu, Apr 9, 2020 at 5:48 PM Stewart Smith <stewart at flamingspork.com> wrote:
>
> On Thu, Apr 9, 2020, at 12:19 AM, Dan Horák wrote:
> > On Wed,  8 Apr 2020 23:12:50 -0700
> > Stewart Smith <stewart at flamingspork.com> wrote:
> >
> > > Based off the Raptor patch:
> > > https://git.raptorcs.com/git/blackbird-skiboot/commit/?id=c81f9d66592dc2a7cf7f6c59c3def5cee0638c1f
> > >
> > > Notable changes:
> > > - slot names matching what's silkscreened on the board
> > > - Expose IPL Observer over op-panel OPAL calls
> > >
> > >   This means you can "printf '\xfe\xfe\xfe' > /dev/op_panel" to
> > >   make the IPL Observer on the Raptor BMC builds to realise it
> > >   can turn on fan control.
> > >
> > > Signed-off-by: Stewart Smith <stewart at flamingspork.com>
> >
> > I like it. Is there any drawback when you write to all 3 addresses
> > (0x80..0x82) as opposed to the original observer that uses only 0x81,
> > 0x82?
>
> the 0x80 is the "standard" (as in, since the original IBM PC) one. The 81,82 came from the "more than 8 bits of status is useful" discussion we (at least Tim and myself, plus others, I can't remember, it's late) had... oh I can't remember now... but a while ago. Our bigger concern was if writing to 81,82 was going to be okay if nothing was listening.

IIRC you'll get one of those "LPC No Sync" errors, but other than that
it doesn't seem to cause any issues.