Why does BIOS 14 on a S2600WFT cause NVMe PCIe drives on CPU0 to not show up?

[Jared_W_Intel]

Issue: Starting from production BIOS SE5C620.86B.00.01.0014.070920180847, when VROC Wolfpass x16 4-port retimer is connected to Riser 1, PCIe slot 1 (CPU0), the NVMe drives don't show up in BIOS (UEFI Option ROM Control), Windows or Linux OS.

Reproducibility: 100%

Board: Silver WolfPass system S2600WFT

BIOS settings: Default settings

Processors: verified on both Xeon Gold and Xeon Platinum Purley Skylake processors

Steps to reproduce:

1. Connect VROC Wolfpass x16 4-port retimer to Riser 1, PCIe slot 1 (CPU0).

2. Connect Oculink to Oculink cables from retimer to Oculink connections on backplane.

3. Insert any Intel NVMe SSDs with U.2 form factor to drive slots where Oculink cables are connected to.

4. Notice with BIOS SE5C620.86B.00.01.0013.030920180427, the drives show up in UEFI Option ROM Control in BIOS.

5. Download production BIOS SE5C620.86B.00.01.0014.070920180847 from https://downloadcenter.intel.com/download/28001/?product=89015

6. Insert USB that contains above BMC/BIOS/ME/FD/FRU/SDR

7. Boot to BIOS and press F9 to load the defaults, then save and reboot

8. Boot to EFI Shell

9. Update BMC

10. Reboot and boot back into BIOS and notice NVMe drives still show up in UEFI Option ROM Control in BIOS.

11. Boot to EFI Shell

12. Update BIOS

13. Reboot and boot back into BIOS and notice NVMe drives no longer show up in UEFI Option ROM Control in BIOS.

Workarounds:

1. Downgrade to BIOS SE5C620.86B.00.01.0013.030920180427 and keep retimer connected to Riser 1, PCIe slot 1

or

2. Keep BIOS SE5C620.86B.00.01.0014.070920180847, but move retimer from Riser 1, PCIe slot 1 to Riser 2, PCIe slot 1 (CPU1)

[idata]

Hello Jared Walton,

Thanks for joining the community.You did a great job gathering all the details for this issue even for recreation purposes. So far there are no issues reported about this latest BIOS version but this could be the very first one. Just a couple questions more1. How possible is to take the SSD backplane out of the equation and connect NVMe drivers directly to retimer card? Do you have cables to allow you do this?2. As a suggestion have you tried to do a CMOS clear using the jumper in the board right after updating the BIOS?Will look forward for you updatesJose A.

[idata]

Hello Jared Walton,

Do you have any updates, questions or comments in regards to this issue?Please do not hesitate to contact us back.If you consider the issue to be completed please let us know so we can proceed to mark this thread as resolved.RegardsJose A.

[idata]

Hello Jared Walton,

We will proceed to mark this thread as resolved. If you have further issues or questions just go ahead and create a new topic.Jose A.