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

[Hanjun Guo <guohanjun@huawei.com>]

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@aa.jp.fujitsu.com>
>>>>>
>>>>> Looks good to me.
>>>>>
>>>>> Reviewed-by: Ilkka Koskinen<ilkka@os.amperecomputing.com>
>>>>>
>>>> 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