topic Re: Re:Which Xeon Processor support PCIe AtomicOps host-to-device transactions? in Intel® Xeon® Processor and Server Products

Which Xeon Processor support PCIe AtomicOps host-to-device transactions?

cary6 — Thu, 31 Jul 2025 07:01:25 GMT

PCIe spec defined 3 types of AtomicOps transactions:

"AtomicOps are architected for device-to-host, device-to-device, and host-to-device transactions."

To verify the system support host-to-device AtomicOps, we write a GPU BAR address to 0, FetchAdd then read back and check whether the data is expected.

On desktop platform Intel Core Ultra 9 285K + RTX5080, that test is OK.

But on Xeon Silver 4410Y + RTX5060, it fails.

RTX50xx GPU supports 32-bit and 64-bit AtomicOp Completer.

Both Ultra9 and 4410Y Root port support Atomic Routing (EgressBlck-).

So why FetchAdd works on Ultra9 but not on Xeon Silver 4410Y?

Which Xeon processor support PCIe AtomicOps host-to-device transactions?

Thanks.

Re:Which Xeon Processor support PCIe AtomicOps host-to-device transactions?

Poojitha — Thu, 31 Jul 2025 17:14:51 GMT

Hi cary6,

Greetings for the day!

Thank you for reaching out to Intel Support. We kindly request some time to review the details and provide you with an update.

We appreciate your understanding!

Best regards,

Poojitha N

Intel Customer Support Technician

Re:Which Xeon Processor support PCIe AtomicOps host-to-device transactions?

IntelSupport — Fri, 01 Aug 2025 07:02:20 GMT

Hi cary6,

Greetings for the day!

I would like to share with you the list of processor families that support AtomicOps:

1. E7 V2

2. E5 2600 v2

3. E7 8800/4800 V3

And please Scalable Family does not.

Regards

Jerome

Intel Customer Support Technician

Re: Re:Which Xeon Processor support PCIe AtomicOps host-to-device transactions?

cary6 — Fri, 01 Aug 2025 09:01:24 GMT

Thank Jerome for your quick response and support.

These processors mentioned above are quite old, we might want to try on Core family processor.

Then the question is: which Core processor support PCIe AtomicOps host-to-device transactions?

Re:Which Xeon Processor support PCIe AtomicOps host-to-device transactions?

Poojitha — Fri, 01 Aug 2025 11:18:26 GMT

Hi cary6,

Greetings for the day!

Thank you for your response. We would like to inform you that Intel® Core™ Ultra Processors for the H-series and U-series support AtomicOps. Please find the complete information in the link below:

https://edc.intel.com/content/www/us/en/design/publications/14th-generation-core-processors-ioe-p-registers/

We appreciate your understanding!

Best regards,

Poojitha N

Intel Customer Support Technician

Re:Which Xeon Processor support PCIe AtomicOps host-to-device transactions?

Poojitha — Mon, 04 Aug 2025 07:47:13 GMT

Hi cary6,

Greetings for the day!

We are following up to check if you were able to find the information we shared. Kindly confirm at your earliest convenience, so that we can continue assisting you in resolving this matter.

We appreciate your understanding!

Regards,

Poojitha

Intel Customer Support Technician

Re: Which Xeon Processor support PCIe AtomicOps host-to-device transactions?

cary6 — Mon, 04 Aug 2025 10:32:31 GMT

Hi Poojitha,

Thank you for your support and time.

We shall try this test on Core and Core Ultra Processors soon. But the final user case is Xeon family processor.

So we shall try Xeon 5 Scalable Family too even if you said it does not support.

Thanks again. This topic is closed.

Re:Which Xeon Processor support PCIe AtomicOps host-to-device transactions?

Poojitha — Tue, 05 Aug 2025 08:03:44 GMT

Hi cary6,

Greetings for the day!

Thank you for your response and for confirming the case closure. We will go ahead and close the case.

And also, kindly note that the product has been discontinued, and Intel Customer Service no longer supports inquiries for it. However, fellow community members may have the knowledge to assist you.

You may also find the Discontinued Products website (https://www.intel.com/content/www/us/en/support/discontinued-products.html ) helpful to address your request.

If you have any questions or concerns in the future, please feel free to reach out to us. We are happy to assist you!

We appreciate your understanding!

Best regards,

Poojitha N

Intel Customer Support Technician