Stratix 10 L-Tile Native PHY Reset Controller

[BeB]

Hello,

I am using a Stratix 10 SX280LN3. To reset the PHY transmitter, the L-Tile Native PHY user guide recommends to "deassert tx_analogreset after the device enters user mode for a minimum duration of 2 ms", and later to "deassert tx_digitalreset after the pll_locked stays asserted for a minimum duration of t_tx_digitaltreset". I have looked throughout the document but could not find a reference to what t_tx_digitaltreset is supposed to be. What is the recommended value for this parameter? I also find it curious that the default value for t_tx_analog reset is 0 in the Reset Controller IP block, if the recommended value is 2ms.

Also, what are the recommended values for the rx reset? There is again a recommend value for t_rx_digitalreset of 5us, which doesn't match the default value in the Reset Controller IP block, but I could not find a recommended value for t_rx_analogreset.

Finally, how does one know that the device is in user mode? Does the Reset Controller IP take care of this?

Thank you for your help,

BeB

[CheePin_C_Intel]

Hi,

As I understand it, you have some inquiries related to the reset sequence of the transceiver. For your information, it is recommended for you to use the XCVR reset controller IP to control the reset sequence of the transceiver. After the device enter user mode, you can trigger a reset to the reset controller.

Regarding the user mode, it is referring to the device programming/initialization completion which is generally indicated by INIT_DONE low-to-high transition.

Please let me know if there is any concern. Thank you.

[BeB]

Hello,

Thank you for your reply, however the questions of appropriate setting remains:

- the default reset controller IP settings do not match the recommended settings mentioned in the native PHY user guide (2ms for tx_analogreset, 5us for rx_digitalreset). Therefore, I have no reason to believe that any of the default settings in the IP block are appropriate.

- what should the reset controller IP settings be for the other timers: tx_digitalreset and rx_analogreset?

Thank you,

BeB

[CheePin_C_Intel]

Hi,

Thanks for your update. For your information, based on my experience, generally users will use the reset controller with the Native PHY to ensure the XCVR can function correctly. The steps mentioned in the user guide seems to be for manual reset if user would like to code their own reset controller. 

The following are my response to your inquiries based on my understanding:

1. 2ms for tx_analogreset

[CP] I believe the reset controller will take care of this waiting period after device enter user mode. The tx_analogreset duration in the IP should be additional delay on top of this 2ms.

2. 5us for rx_digitalreset

[CP] For your information, as I look at the S10 XCVR reset controller, it seems like by default the rx_digitalreset duration = 5000ns. Just would like to check with you which Quartus version that you are using? Mind share with me the default setting screenshot from your Quartus version?

3. what should the reset controller IP settings be for the other timers: tx_digitalreset and rx_analogreset?

[CP] Please use the default settings in the reset controller.

Please let me know if there is any concern. Thank you.

[BeB]

Hello,

Thank you for your reply.

The user guide provides a power up reset sequence (i.e. when the device enters user mode), and a run-time reset sequence.

To address your points:

1] If I look at the verilog code, it doesn't look like the reset controller takes care of the 2ms. Whatever setting is entered for tx_analogreset duration is what is applied via a counter that starts with the reset signal.

2] I am using Quartus 19.1. My apologies, the rx_digitalreset duration is indeed 5000ns by default. I am attaching a screenshot of the default settings.

3] OK, thank you. The default values are 20ns and 40ns respectively FYI.

Thanks again, please see the attached screenshot.

BeB

[CheePin_C_Intel · Accepted solution]

Hi,

Thanks for your update. For your information, I do not have further insight into how internally the hardware handle the 2ms. Sorry for the inconvenience. However, based on my experience, generally users will use the reset controller to ensure correct functionality of the transceiver. Therefore, it is recommended for you to use the reset controller.

Please let me know if there is any concern. Thank you.

[CheePin_C_Intel]

Hi,

I believe the initial inquiry has been addressed. This thread will be transitioned to community support. If you have a new question, feel free to open a new thread to get the support from Intel experts. Otherwise, the community users will continue to help you on this thread. Thank you.