PIPE Direct Reset Release Sequence

Hi Jayden ,

Question 1,
I am recommended to release lnX_pipe_direct_pld_pcs_rst_n_i (Step 4) in the domain of ln0_pipe_direct_pld_tx_clk_out_o, or at least synchronously to it. This ensures the reset release and subsequent logic initialization are properly aligned with the TX clock domain, avoiding metastability and timing issues. While you can use another clock with CDC (clock domain crossing) synchronizers, doing so adds complexity and risk. If you must use a different clock, you must guarantee that the de-assertion is properly synchronized into the TX clock domain, typically with a multi-flop synchronizer.

Question 2,
Increase your SignalTap pre-trigger buffer to capture events before and after your trigger, so you can see the full sequence.

Question 3,
I have work with few other customer before, and they are able to bring up the phystatus and cdrlock2data.
IF this happen, I would suggest you to check back your logic carefully. few of the common mistake will be make sure lnX_pipe_direct_powerdown_i follows the correct state transitions (P1 → P0 as per PIPE). Double-check reset release timing: Ensure lnX_pipe_direct_pld_pcs_rst_n_i is released after lnX_pipe_direct_tx_transfer_en_o and the TX clock is valid. It is quite hard to narrow down in one single reply, But I hope I am able to provide the best tips for you to narrow the issue quicky.

This guide is helpful for your logic designing, perhaps you can refer
https://www.intel.com/content/www/us/en/io/pci-express/phy-interface-pci-express-sata-usb30-architectures-3-1.html

However, for PIPE Direct mode, there are no example design available, so at the moment I do not have a way to validate this behavior with RTL simulation.

If anyone has experience debugging Figure 50 on real hardware, I would appreciate guidance.
>> We do have technical Partner that is fully validate this in real HW design.
>> IF you need a turnkey solution do consult your local Altera Distributor/sales to get the partner name.
>> or else, me and the community contributor will continue to ensure your success via this forum platform.

Regards,
Wincent