Re: [PATCH] - Add IOAPIC NMI support on x86_64

John Keller
2007-06-19T13:34:23Z

>
> John Keller <jpk@sgi.com> writes:
>
> > Add support for IOAPIC NMI interrupts on x86_64.
> >
> > Changes include the following:
> >
> > - Obtain the NMI IOAPIC info via an ACPI NMI SRC structure that is
> > part of the MADT, and program the IOAPIC redirection register.
> > The NMI SRC struct will contain the GSI of the NMI interrupt.
> >
> > - Setup irq_desc[] and irq_2_pin[] entries for the NMI interrupt irq,
> > which will be used by the generic mask/unmask routines. This will
> > allow a driver to enable/disable the NMI interrupt via
> > enable/disable_irq().
>
> What's the motivation for this patch?

In our specific case, a loadable driver will register to process
the NMI generated by a timer device on the IOAPIC pin. The driver
will need to unmask/mask the NMI interrupt at init/exit time.

The timer NMI interrupt will be used to synchronize cluster nodes.

John

>
> -Andi
>