[Skiboot] [PATCH v2] System reset IPI facility and Mambo implementation

[Oliver O'Halloran]

On Wed, 2017-02-08 at 17:42 +0530, ppaidipe wrote:
> On 2017-02-08 14:04, Nicholas Piggin wrote:
> > Add an opal call OPAL_SIGNAL_SYSTEM_RESET which allows system reset
> > exceptions to be raised on other CPUs and act as an NMI IPI. There
> > is an initial simple Mambo implementation, but allowances are made
> > for a more complex hardware implementation.
> > 
> > This API is based on the POWER8 implementation from Alistair
> > Popple.
> > 
> > Signed-off-by: Nicholas Piggin <npiggin at gmail.com>
> > ---
> > Changes since v1:
> > 
> > - Moved to .rst.
> > 
> > - Mambo broadcast change to signal our CPU last, to ensure all CPUs
> >   get system reset interrupts independently.
> > 
> > - OPAL_PARTIAL error can be kept for platform specific restrictions
> >   without putting any restrictions on implmentations. We may or may
> >   not used it for the POWER8 implementation.
> > 
> >  doc/opal-api/opal-signal-system-reset-145.rst | 43 
> > ++++++++++++++++++++++
> >  include/opal-api.h                            |  3 +-
> >  platforms/mambo/mambo.c                       | 52 
> > +++++++++++++++++++++++++++
> >  3 files changed, 97 insertions(+), 1 deletion(-)
> >  create mode 100644 doc/opal-api/opal-signal-system-reset-145.rst
> > 
> > diff --git a/doc/opal-api/opal-signal-system-reset-145.rst
> > b/doc/opal-api/opal-signal-system-reset-145.rst
> > new file mode 100644
> > index 00000000..e5b7177c
> > --- /dev/null
> > +++ b/doc/opal-api/opal-signal-system-reset-145.rst
> > @@ -0,0 +1,42 @@
> > +OPAL_SIGNAL_SYSTEM_RESET
> > +========================
> > +::
> > +   int64_t signal_system_reset(int32_t cpu_nr);
> 
> I think it should be like below, as it implements only for mambo 
> platform.
> int64_t mambo_signal_system_reset(int32_t cpu_nr);
> 
> Thanks
> Pridhiviraj

This interface is intended to be a general purpose mechanism that
supported across all platforms. Actually implementing this on real
hardware is quite involved (See Alistair's earlier patches), but the
Mambo version is fairly simple so Nick is using that as a prototyping
platform.

Oliver