Re: Question on MSI support in PCI and PCI-E devices

[Andrey Utkin]

On Mon, Mar 2, 2015 at 4:02 PM, McKay, Luke <Luke.McKay@xxxxxxxxxxxx> wrote:
> It doesn't appear that your device supports MSI.  If it did lspci -v should list the MSI capability and whether or not it is enabled.
>
> i.e. Something like...
> Capabilities: [68] MSI: Enable+ Count=1/1 Maskable- 64bit+
>
> Without a listing that shows the capability is present, there is nothing to enable.
>
> Have you tried polling instead of using interrupts?  Definitely not ideal, but it might help you to determine whether hardware is dropping/missing an interrupt or whether the hardware is being completely hung up.
>
> Do you know if this missing interrupt is occurring in other systems as well?  How about whether it happens with different boards in the same system?  Answers to these questions would help to determine whether you might have a defective board, or some sort of incompatibility with the system.

We have just three setups reproducing this. We have no boards for
replacement experiments, unfortunately.
Polling instead of using interrupts sounds interesting. Is there an
example of such usage in any other PCI device driver?

-- 
Bluecherry developer.
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