Add MSI/MSI-X interrupts support to VISA

[Anton.S]

Hi!

PCI Express bus became more and more popular.
PCIe has a new type of interrupts - MSI/MSI-X.
Today VISA driver is able to work only with old style interrupts (Legacy).

Let me explain the main difference:

Legacy interrupt mask intA/B/C/D signals (these signals was in PCI bus, but not exist in PCIe bus).
These signals (for PCIe actually packets with Message setA/B/C/D) are shared between all PCIe devices.
So VISA driver spend a lot of time when it looks who produced this interrupt.

MSI interrupt is actually a Memory Write packet to preallocated address.
In this case VISA should already know which device produced this interrupt.
Also MSI interrupt can contain different interrupt vectors inside of Memory Write packet. So it would be very helpful to get access to vector value too.

Requesting MSI/MSI-X interrupts support to VISA driver.

Thanks a lot!

[ABV]

Is is steal right, that NI VISA officially doesn't support MSI interruptions?

So, we well try to make our new Informtest Visa for PXIe support MSI and MSI-X interruptions!

That will be a challenge!

[Anton.S]

Hi!
I think the answer is still "yes".
Keep in touch, it is impressive task!

[Milwaukee_Ethan]

Hi All!

Please let me know if you are already solved this issue?

I need to develop a PCIe driver through VISA recently, but seems NI VISA still doesn't support MSI interrupt after serching manuals and send email to NI support.

Thanks a lot!