FPGA Developer

Imagine for a minute that you wake up one day and you realize that you have a superpower — like the ability to fly. Well, that’s a bit like how I felt when I started using Claude Code about a month ago. Since then, when I talk and write about my experiences with this amazing new tool, I find myself trying to hold back my excitement, trying not to look like a crazy person. It’s like I feel the ground shaking beneath my feet while I see other people around me going about their lives as usual. I would tell people that this is huge, that it has flipped the tables on my work and the whole tech industry — but I’d see that they were not as shocked as I was. Claude Code was blowing my mind. The truth is that it has completely changed the way I work, at least when it comes to one big part of my work, and I struggle to imagine ever going back.

U.2 NVMe SSDs are the types of drives that are commonly used in enterprise servers and data centers. Compared to M.2 NVMe SSDs, which are more commonly found in consumer devices, U.2 drives are physically bigger, using the same form factor as the 2.5 inch SATA SSDs. The bigger form factor allows U.2 drives to consume more power and thus deliver higher sustained performance than their equivalent M.2 versions. This performance advantage is the reason why U.2 SSDs are becoming more popular in FPGA applications.

Hands down, the best solution for non-volatile storage on Versal designs, is NVMe solid-state drives. One of the main reasons why they are such a good fit is because they interface with the host device over PCI Express. Versal Prime, AI Core and AI Edge devices all have integrated PCIe blocks, and most of them are PCIe Gen5 compliant. This means that there are no extra IP costs to connect an NVMe SSD to the Versal devices because everything you need is already built into the device.

Ten years ago, almost to the day, I launched the Opsero Ethernet FMC. To my delight and surprise, many of our customers are still buying them today. Gigabit Ethernet still finds many uses in FPGA designs today, because it is simple to setup, the cabling is easy to buy and install, the throughput is ample for many applications and it is extremely versatile.

This year, I felt that it was time to upgrade our Ethernet FMC offering, so we’ve launched two new products: Quad SFP28 FMC which I have introduced to you in earlier posts (here and here), and Ethernet FMC Max, which I would like to introduce to you in this post.

In this post we’re going to build and run our new multi-port 25G Ethernet reference design for Versal boards and the Opsero Quad SFP28 FMC. The design is based on the AMD Xilinx 10G/25G Ethernet Subsystem IP. Specifically, we’re going to boot PetaLinux on the VEK280 and establish a 25G Ethernet connection between it and a 25G network adapter that is installed in a Ubuntu PC. We’re doing this on Versal board VEK280 which is one of the few AMD FPGA-containing devices that can support 25G Ethernet at the time of writing. The instructions can also be applied to Versal boards VCK190, VMK180 and VPK120; there is a reference design for all of these boards in the Github repo.

In the next few days I will kick off the launch of another new Opsero FMC product: the Quad SFP28 FMC. This FMC card has 4x SFP28 slots that are compatible with SFP, SFP+ and SFP28 modules. The FMC and the reference designs that we are currently developing will enable 4x 10G/25G Ethernet links on a multitude of FPGA/MPSoC/RFSoC development boards including the newer Versal ACAP boards. We’ve already pushed working 10G/25G designs to the Github repo for the ZCU104, ZCU102, ZCU106, ZCU111 and ZCU208 with more coming soon.

Here we go again. In this post I’m going to go through the steps of installing Vitis and PetaLinux 2024.1. Unfortunately I have to go through this process on a regular basis. Installing dev tools like this from the biggest FPGA vendor in the world should be easy but for some reason there are always problems - hence the need to keep notes.

The image that I used for this post was generated by ChatGPT.

The FPGA Mezzanine Card standard (VITA 57.1) has significantly enhanced the FPGA ecosystem by decoupling the FPGA board from the input/output components. Years ago, if you wanted to process samples from an ADC, you would buy an FPGA board with an on-board ADC. If you wanted to add a DAC, or upgrade the ADC, you would replace the entire board! The FMC innovation provided developers with choice, so that they could select the right FPGA for their specific I/O requirements. They could also swap-out their I/O cards as their needs changed or as upgrades or improvements became available.

Important

This workaround is applicable to the VCK190, VMK180 and VPK120 because they all use the same circuitry for generating the VADJ voltage: an IR38164 buck regulator with the same I2C address (0x1E), connecting to the same port of the same I2C switch (address 0x74, port 0) and connecting to the same I2C pins of the Versal device (PMC MIO46/47).

Note that this workaround is NOT applicable to the VEK280 because that board applies a fixed VADJ voltage of 1.5VDC.

High-capacity non-volatile storage is pretty handy in the intensive computing applications that the Versal ACAP adaptive SoCs get employed in. NVMe SSDs are a perfect way to provide that storage because they can directly interface with the Versal’s integrated blocks for PCIe. Those integrated blocks are Gen4 compliant which makes for an extremely high bandwidth connection between the FPGA fabric and the storage medium.

Over the past couple of weeks, my team and I have been bringing up an NVMe SSD on the Versal AI Core VCK190 Evaluation kit using the FPGA Drive FMC Gen4 adapter. We’ve built a new reference design from our work and shared it on Github. In this post we’ll look at how you can build and run the example design, and then we’ll partition and write a file to one of the SSDs. For those who are trying to do this from scratch using the QDMA Subsystem for PCIe IP, Vivado and PetaLinux, the last half of this post will be about the things that we found to be important in getting everything working correctly.