where is the RDH register in i40e

[jimmy_tusim]

Hi,

     I am working on monitoring the ring buffer usage in the NIC, and I need to have access to the head pointers of each ring buffer, after I check i40e_register.h, I did not find the RDH register. May I know where it is. ( The head pointer I am referring to is the same as the RDH in e1000e, which can be found in regs.h:

#define E1000_RDH(_n) ((_n) < 4 ? (0x02810 + ((_n) * 0x100)) : \

(0x0C010 + ((_n) * 0x40)))

)Thank you.

Best,

Jimmy

[AlfredoS_Intel]

Hi Jimmy_tusim,

Thank you for posting in Intel Ethernet Communities.

Please answer the following question which will help us get more context on your issue.

1. It looks like you are building a custom design system. Are you incorporating the chip to an Intel Field Programmable Array (FPGA), System on Chip (SOC), Complex programmable logic device (CPLD)?

We look forward to your reply. Should we not get your reply, we will follow up after three business days.

Best Regards,

Alfred S

Intel® Customer Support 

[jimmy_tusim]

Hi,

    I am working on a X722 NIC (Intel Corporation Ethernet Connection X722 for 10GBASE-T).  It is using i40e-2.12.6 driver downloaded from intel webpage. 

Jimmy

[AlfredoS_Intel]

Hi Jimmy_tusim,

Thank you for your response.

What software are you using to create the code? Is it an Intel software or development kit?

We look forward to your reply. Should we not get your reply, we will follow up after three business days.

Best Regards,

Alfred S

Intel® Customer Support

[jimmy_tusim]

Hi

   It is intel software, downloaded from https://downloadcenter.intel.com/downloads/eula/24411/Intel-Network-Adapter-Driver-for-PCIe-40-Gigabit-Ethernet-Network-Connections-under-Linux-?httpDown=https%3A%2F%2Fdownloadmirror.intel.com%2F24411%2Feng%2Fi40e-2.12.6.tar.gz

  I just want to modify the code so it can print some variable via debugfs. 

Best,

Jimmy

[AlfredoS_Intel]

Hi Jimmy_tusim,

Thank you providing those information.

Please allow us some time to check on this. 

We will get back to you no later than 3 business days from now.

Best Regards,

Alfred S

Intel® Customer Support 

[AlfredoS_Intel]

Hi Jimmy_tusim,

Thank you for waiting for our update.

While we were closely checking your concern, we find the need to get a more extensive look on your system configuration.

Please download and run our Intel® System Support Utility from this page, https://downloadcenter.intel.com/download/26735/Intel-System-Support-Utility-for-the-Linux-Operating-System#:~:text=Intel%20SSU%20for%20the%20Linux,and%20shared%20by%20the%20user. After running it, you will be given an option to save the logs to a text file, please do so and attach the file on your reply.

Since you are running Linux, kindly provide us the output of this command as well, : ethtool -i ethx where ethx is the Ethernet port.

We look forward to your reply. Should we not get your reply, we will follow up after three business days.

Best Regards,

Alfred S

Intel® Customer Support

[jimmy_tusim]

Hi,

 ethtool -i LAN:

driver: i40e
version: 2.12.6
firmware-version: 3.25 0x800009d3 1.1638.0
expansion-rom-version:
bus-info: 0000:1a:00.1
supports-statistics: yes
supports-test: yes
supports-eeprom-access: yes
supports-register-dump: yes
supports-priv-flags: yes

ssu.sh gives:

- "Intel Corporation Ethernet Connection X722 for 10GBASE-T (rev 09)"
Supports auto-negotiation:"Yes"
Advertised auto-negotiation:"Yes"
Auto-negotiation:"on"
Availability:"UP BROADCAST RUNNING MULTICAST MTU:9000 Metric:1"
Capabilities:"[40] Power Management version 3"
Capabilities:"[50] MSI: Enable- Count=1/1 Maskable+ 64bit+"
Capabilities:"[70] MSI-X: Enable+ Count=129 Masked-"
Capabilities:"[a0] Express Endpoint, MSI 00"
Capabilities:"[e0] Vital Product Data"
Capabilities:"[100] Advanced Error Reporting"
Capabilities:"[140] Device Serial Number 0c-31-53-ff-ff-ad-00-c4"
Capabilities:"[150] Alternative Routing-ID Interpretation (ARI)"
Capabilities:"[160] Single Root I/O Virtualization (SR-IOV)"
Capabilities:"[1a0] Transaction Processing Hints"
Capabilities:"[1b0] Access Control Services"
Caption:"Not Available"
Default IP Gateway:"Not Available"
DHCP Enabled:"Yes"
DHCP Lease Expires:"Not Available"
DHCP Lease Obtained:"Not Available"
DHCP Server:"Not Available"
Driver:"i40e"
Driver Path:"/lib/modules/4.19.57-041957-generic/kernel/drivers/net/ethernet/intel/i40e/i40e.ko"
Driver Provider:"Intel Corporation, <e1000-devel@lists.sourceforge.net>"
Driver Version:""
Duplex:"Full"
Firmware Version:"3.25 0x800009d3 1.1638.0"
Interface:"LAN"
I/O Ports:"Not Available"
IP Address:"192.168.100.3"
IP Subnet:"255.255.255.0"
MAC Address:"c4:00:ad:53:31:0d"
Location:"1a:00.1"
Manufacturer:"Intel Corporation"
Net Connection ID:"Ethernet"
Port:"Twisted Pair"
Power Management:"Supports Wake-on: g"
Power Management:"Wake-on: g"
Speed:"10000Mb/s"
Supported link modes:"1000baseT/Full, 10000baseT/Full, Supported pause frame use: Symmetric"
Advertised link modes:"1000baseT/Full, 10000baseT/Full, Advertised pause frame use: No"
Partner advertised link modes:"Not Available"

Maybe there is some misunderstanding, I just want to know which register in i40e/registers.h refers to the RDH register as in e1000e driver. Because there were not enough comments for me to identify it in the header file. And I think it does not matter which kind of cpu or RAM I am using. 

Best,

Jimmy 

[AlfredoS_Intel]

Hi Jimmy_tusim,

Thank you for providing that information.

We will continue checking this and the information that provided is invaluable to us.

Please allow us some time to check on this. We hope for your understanding regarding this

We will get back to you no later than 3 business days from now.

Best Regards,

Alfred S

Intel® Customer Support 

[jimmy_tusim]

Hi, is there any updates? 

[AlfredoS_Intel]

Hi Jimmy_tusim,

Thank you for your patience in waiting for an update.

Due to the complexity of the issue, please allow us more time to check on your concern.

We will try to get back to you with an answer no later than 3 business days from now; although, we will reach out to you in case we need more information or if we already have developments regarding your concern.

Best Regards,

Alfred S

Intel® Customer Support

[AlfredoS_Intel]

Hi Jimmy_tusim,

Thank you for waiting for our update.

Here is our current update for you:

According to our engineering team, they have checked both documentations and codes but they don’t see a register containing RX queue head in the driver. There are only QTX_HEAD, QTX_TAIL and QRX_TAIL registers mapped in the driver, and they are still researching for it.

We will get back to you no later than 3 business days from now.

Best Regards,

Alfred S

Intel® Customer Support

[AlfredoS_Intel · Accepted solution]

Hi Jimmy_tusim,

Thank you for waiting for our update.

After further validation with our engineers, we regret to inform you that the QRX_HEAD register is not used in the driver, and the FW does not handle this register as it is directly mapped to the HW. Unfortunately, there is no further way to extract and read the information.

We hope for your understanding regarding this.

We would like to hear your thoughts or if you have further questions please feel free to reply.

We look forward to your reply. Should we not get your reply, we will follow up after three business days.

Best Regards,

Alfred S

Intel® Customer Support

[jimmy_tusim]

 Got it. Thank you for your help.

[AlfredoS_Intel]

Hi Jimmy_tusim,

Good day! We hope that you are having a fantastic one.

We are posting this message to inform you that we need to close this ticket since you have marked our thread as “closed”.

If you still need assistance with your ticket, please just contact us again or submit another ticket online and we will be more than glad to help you.

Thank you for contacting Intel® and have a great day!

Best Regards,

Alfred S

Intel® Customer Support