Is it able to use DDIO for sumsung NVMe SSD on Intel(R) Xeon(R) CPU E5-2670 v3?

[HenryHP]

Hi there,

As I know E5 family processors support DDIO and it can be enabled/disabled via perfctrlsts_0 register. 

I tried to change 8th bit(Use_Allocating_Flow_Wr) of the perfctrlsts_0 register to change DDIO configuration for a specific device.

However, some devices do not allow to change the bit which means that the bit is not changed even if I set the bit while some devices allow it.  

I want to use DDIO for Samsung NVMe SSD PM 981. But, it is not able to set Use_Allocating_Flow_Wr bit. I tried to change bit(using pic_write_xxx()), but the value is not changed.

Can you please let me know I can use DDIO for all PCIe devices or only some devices can utilize DDIO?

Thanks,

Henry

[Paul_R_Intel]

Hello HenryHP, 

Thank you for joining the community, please allow us to investigate this inquiry and we will get back to you as soon as possible.

Regards 

Paul R. 

Intel Customer Support Technician 

For firmware updates and troubleshooting tips, visit: 

https://intel.com/support/serverbios 

[HenryHP]

Hi Paul,

Thanks for your reply.

I tested out intel devices, NVMe SSD(INTEL SSDPE2MW400G4 ) and NIC(Intel Corporation 82574L Gigabit Network Connection).

But the perfctrlsts_0 register values of these devices are not changed too.

Here is the enable/disable sample code that I used:

---------------enable------------------

val=pci_read_long(dev, PERFCTRLSTS_0/*0x180*/);

pci_write_long(dev, PERFCTRLSTS_0, val |  use_allocating_flow_wr_MASK/*0x80*/);
---------------disable------------------

val=pci_read_long(dev, PERFCTRLSTS_0/*0x180*/);

pci_write_long(dev, PERFCTRLSTS_0, val&(~use_allocating_flow_wr_MASK/*0x80*/));

------------------------------------------

This code works well for "Host bridge: Intel Corporation Xeon E7 v3/Xeon E5 v3/Core i7 DMI2 ", "RAID bus controller: LSI Logic / Symbios Logic MegaRAID SAS-3 3108 ", or some others.

I mean the Use_Allocating_Flow_Wr bit of perfctrlsts_0 is changed properly.

Thanks for your help!

Henry

[Paul_R_Intel]

Hello HenryHP, 

I hope you are doing great, thank you for the update. DDIO is already disabled by default on Haswell processors, so we would like to know a few things in order to better assist you:

• Do you see that DDIO is disabled by default?
• Can you please share how you confirmed that DDIO is disabled?

Please also run the following script and share the outcome:

lspci -s 00:1.0 -xxxx | awk -v pat=180 -v v=128 -v m=0x80 '$0 ~ pat {print ((and(strtonum("0x"$2), strtonum(m)) == v) ?"on":"off")}'

lspci -s 00:2.0 -xxxx | awk -v pat=180 -v v=128 -v m=0x80 '$0 ~ pat {print ((and(strtonum("0x"$2), strtonum(m)) == v) ?"on":"off")}'

lspci -s 00:3.0 -xxxx | awk -v pat=180 -v v=128 -v m=0x80 '$0 ~ pat {print ((and(strtonum("0x"$2), strtonum(m)) == v) ?"on":"off")}'

We will be waiting for your response

Regards 

Paul R. 

Intel Customer Support Technician 

For firmware updates and troubleshooting tips, visit: 

https://intel.com/support/serverbios 

[Paul_R_Intel]

Hello HenryHP, 

I hope you are doing great, we would like to know if you were able to check the last post and recommendations.

Regards 

Paul R. 

Intel Customer Support Technician 

For firmware updates and troubleshooting tips, visit: 

https://intel.com/support/serverbios 

[Paul_R_Intel]

Hello HenryHP, 

I hope you are doing great, we would like to know if you were able to check the last post and recommendations and the outcome, if we do not hear from you we will follow up a last time on 02/03rd.

Regards 

Paul R. 

Intel Customer Support Technician 

For firmware updates and troubleshooting tips, visit: 

https://intel.com/support/serverbios 

[Paul_R_Intel]

Hello HenryHP, 

I hope you are doing great, as we have not heard back from you we will mark the thread as close. You may reopen it by replying back.

Thank you for choosing Intel.

Regards 

Paul R. 

Intel Customer Support Technician 

For firmware updates and troubleshooting tips, visit: 

https://intel.com/support/serverbios