Re: [PATCH v3] ACPI: AGDI: Add interrupt signaling mode support

[Hanjun Guo]

On 2025/9/29 15:32, Kazuhiro Abe (Fujitsu) wrote:
> Hi Hanjun,
>
> > > Hi Hanjun & Sudeep
> > >
> > > > Hi Ilkka
> > > >
> > > > > Hi Kazuhiro,
> > > > >
> > > > > On Fri, 5 Sep 2025, Kazuhiro Abe wrote:
> > > > > > AGDI has two types of signaling modes: SDEI and interrupt.
> > > > > > Currently, the AGDI driver only supports SDEI.
> > > > > > Therefore, add support for interrupt signaling mode The interrupt
> > > > > > vector is retrieved from the AGDI table, and call panic function
> > > > > > when an interrupt occurs.
> > > > > >
> > > > > > Signed-off-by: Kazuhiro Abe<fj1078ii@xxxxxxxxxxxxxxxxx>
> > > > >
> > > > > Looks good to me.
> > > > >
> > > > > Reviewed-by: Ilkka Koskinen<ilkka@xxxxxxxxxxxxxxxxxxxxxx>
> > > > Thanks for your review.
> > > >
> > > > Best Regards,
> > > > Kazuhiro Abe
> > > >
> > > > > Hanjun & Sudeep, what's your thought on enabling the use of regular
> > > > > interrupts here? I do agree the spec talks about non-maskable ones
> > > > > and to my understanding that's what the idea was indeed.
> > > Do you have any thoughts on this matter?
> > For the real use case, if the system is in failure state, for example, the system is
> > panic, the CPU will not handle regular interrupts, so what's the use case do you
> > have to use regular interrupt?
> This driver is designed to operate with NMI enabled.
>
> However, on current ARM64 platforms, NMI functionality may not be active unless
> "pseudo NMI" is explicitly specified via a kernel command-line parameter.
> In such scenarios, we've included regular interrupt handling as a last resort,
> anticipating rare cases where some cores might still be able to receive regular
> interrupts even if other cores are unresponsive.
>
> To reiterate, the underlying assumption is that NMI(now pseudo NMI) is enabled for use.

OK. Please send a new version, I will ack it
if you address my comments.

Thanks
Hanjun