Re: [PATCH v4] cdx: add MSI support for CDX bus

Gupta, Nipun
2023-10-05T16:13:26Z

Hi Greg,

On 10/5/2023 7:30 PM, Greg KH wrote:
> On Thu, Oct 05, 2023 at 03:46:34PM +0200, Thomas Gleixner wrote:
>> On Thu, Oct 05 2023 at 12:24, Greg KH wrote:
>>>> diff --git a/drivers/cdx/Kconfig b/drivers/cdx/Kconfig
>>>> index a08958485e31..86df7ccb76bb 100644
>>>> --- a/drivers/cdx/Kconfig
>>>> +++ b/drivers/cdx/Kconfig
>>>> @@ -8,6 +8,7 @@
>>>> config CDX_BUS
>>>> bool "CDX Bus driver"
>>>> depends on OF && ARM64
>>>> + select GENERIC_MSI_IRQ_DOMAIN
>>>
>>> This config option isn't in my tree anywhere, where did it come from?
>>> What is it supposed to do?
>>
>> 13e7accb81d6 ("genirq: Get rid of GENERIC_MSI_IRQ_DOMAIN") :)
>
> Ok, so this hasn't been tested since the 6.2 release? Wow, I think
> someone from AMD needs to take a deep look at this and verify that it
> actually is doing what it is supposed to be doing...

The patch Thomas mentioned renames "GENERIC_MSI_IRQ_DOMAIN" to
"GENERIC_MSI_IRQ"; and in our testing "GENERIC_MSI_IRQ" is also selected
as 'ARM64' is enabled which enables 'ARM_GIC_V3_ITS' which in-turn
selects 'GENERIC_MSI_IRQ'.

The patch is tested for MSI functionality on 6.6-rc1. We will re-look
into the config dependencies to avoid such issues, but please be assured
that the patch has been validated.

Thanks,
Nipun

>
> thanks,
>
> greg k-h