Re: [PATCH 4/5] PCI: iproc: Add iProc PCIe MSI support

Ray Jui
2015-11-19T23:06:31Z

Hi Arnd,

On 11/19/2015 12:31 AM, Arnd Bergmann wrote:
> On Wednesday 18 November 2015 17:37:16 Ray Jui wrote:

>> I haven't spent too much time investigating, and am hoping to eventually
>> enable affinity support with an incremental patch in the future when I
>> have more time to investigate.
>
> Is it possible that you have a set of MSIs per GIC interrupt (as Marc
> suggested earlier) and that the way it is intended to be used is by
> having each one of them target a different CPU? That way you can do
> affinity by switching to a different MSI in .set_affinity(), I think
> that is how the old style MSI all used to work when each CPU had its
> own MSI register.
>
> Arnd
>

Okay, I see that Xgene MSI has a very similar implementation to support
MSI IRQ affinity. I plan to take a closer look and try it out in the
future. But it likely won't be included in the current round of patch set.

Thanks,

Ray