04-23-2018 01:35 AM
It looks to me that using multiple GTs in a quad for UHD-SDI on Kintex Ultrascale+ is not working.
I started from example design for KCU116, generated from the UHD-SDI RX SS, using Vivado 2018.1. I'm therefore using GTYs.
I then made the few modifications necessary for me (namely using another quad because I'm using SDI SFPs instead of an FMC module).
I could compile the project and check that SDI video was working as expected (I didn't check audio part).
I then added more than 1 GT in the quad by customizing the UHD-SDI GT IP. I then realized that while GT1 is connected, the 3 other GTs are unconnected. The compilation fails because constraints about 3 of the GT connections are not correct (since they are unconnected). That is not obvious but the following post-implementation schematic screenshot shows that 3 GT TX are not connected to GT (because of use of OBUF and because Vivado picks "random" FPGA pins for them). For RX, I know from reports and other attempts that 3 GT are unconnected:
And here is how I connected the UHD-SDI GT IP. I simply connected ports / logic from example design to 4th GT and chained IN/OUT for the 3 others:
Any idea on how to make use of more than 1 GT in the quad for UHD-SDI GT IP?
Thanks in advance.
04-24-2018 02:05 AM
04-23-2018 02:07 AM
When you say you added on more GT, go you mean you increased the number of links in the UHD-SDI GT core?
If this is the case, there is a known issue. Development is working on it.
Could you try by using 2 different UHD-SDI GT with only one with the GT common (using Figure C-4 from pg2902 as reference)?
04-23-2018 02:20 AM
I moved from 1 to 4 links in the UHD-SDI GT core indeed.
Do you know how long will it take for development to solve this? Is it more about 2 weeks or 3 months?
I will try what you suggest (PG290, figure C-4).
04-23-2018 02:49 AM
I hope the issue to be fixed in few weeks. But I cannot garanty anything.
04-23-2018 11:45 PM
I sent you the patch which should become public in the next few days.
04-24-2018 02:05 AM