Electronics > FPGA

Lattice Certus-NX PCIe, or alternative

(1/4) > >>

davorin:
Good afternoon

On the search for an FPGA with built-in PCIe block I stumbled upon the Lattice Certus-NX product and the corresponding PCIe eval board...
But when I do a simple design with the PCIe x1 core enabled, synthesize is okay but mapping fails...

So is this again another product from LAttice where they require you to buy an expensive 1-year license to use what's already built-in?

Is there another, preferrably low-cost, FPGA alternative which doesn't require you to buy a license and can be used with a free synthesize tool?


thanks in advance
richard

PS: At least their Radiant software is easier to install compared to the alien rpm fiddling on a Debian system requiring you to install obsolete libraries (o;

mon2:
Do you require native PCIe support? Gen1 or is it faster ?

A practical approach is to consider a PCIe to PCI bridge and then apply the Gowin PCI FPGA with their free toolchain. Much more cost effective. The lack of proper support with Lattice is disturbing. It is obvious that they do not wish to entertain the smaller developers.

For the PCIe to PCI transparent bridge, recommend the Diodes (aka Pericom) line. We have very high volumes of designs using this approach using ASSP PCI bus devices. The use of Gowin FPGA for PCI bus is on our pending project list.

davorin:
Interesting approach...know Pericom from 20 years ago with their logic level shifters....
Also interesting you use Gowin....evaluating them for another project.

Native would be nice...also for the learning factor....dunno if Xilinx offers a license free implementation..
project is a simple pcie x1 io board to put on github...

Haven't checked Trion devices what they offer...

But sure I'll have a look at Pericom...

mon2:
Can you share more details on your requirements for the GPIO interface? Would like to at least offer component details where we can.

The Diodes PI7C9X113SL is a transparent PCIe to PCI bus bridge for Gen1 speed. It will be backwards compatible with all PCIe slots (x1 -> x16). We use them in many of our designs. The current market price is insane. The drop in replacement is the PI7C9X118SL. Same device, different p/n. Don't ask...

There is some stock of this device available from Mouser. We can help to review your schematic if needed but is very simple to deploy. The bridge features an EEPROM to correct / program any of the default registers but to date, have shipped product with the eeprom blank. No compatibility issues to date using a 4L PCB with impedance controlled traces for the PCIe bus layout (Gen1 speed).

Fairly sure the PCIe to PCI bridge offers GPIO pins onboard. However, can certainly see the value to use a FPGA to bit bang out some state machine, etc. so the idea of a native PCIe or PCI device inside a FPGA is desirable.

Efinix is a good company to watch but had to side track for the past few months to Gowin as Efinix does not offer MPI DSI support where as Gowin does. Gowin is very cost effective for their devices (work with Edge Electronics in the USA for the best pricing if you can). We are sourcing through them but having the parts drop shipped to us from HK to save on the USA applied tariffs as we are in Canada.

The support from Gowin is top notch - the best we have seen from the assorted FPGA firms we have dealt with to date. Most of the FPGA vendors / factories do not reply back to us and others report - 'just read the docs and work it out' comments. After weeks and weeks of troubleshooting, we convinced the factory, every time, that they made mistakes.

What is our time worth ? To where do we send my invoice ? Tired of correcting other's mistakes in the semiconductor business and all this so we can buy their silicon?? We are far from being verilog and FPGA pros but getting very comfortable with Gowin tools. Just need to study their GAO. Have an excellent support contact in the USA if you need help.

Consider a Gowin FPGA with a hard CM3 CPU with enough LUTS to allow you to embed the PCI bus interface. Then the FPGA fabric and handle the GPIO or you can use the CM3 (will be slower).

One key concern is that what about the device driver to support this widget. You are ok to write code for Windows / Linux drivers ?

Also, a good website in case you have not seen it...

https://www.fpga4fun.com/PCI-Express.html

Jean has excellent articles on this website. We have learned a great deal about FPGA from here.

asmi:
Xilinx offers free IP for PCI Express endpoint or root port. Just this week I've built a Linux system on Zynq 015 with PCI Express 2.0 x2 root port using that IP and got few PCIE cards I had around to work (among them 2.5G ethernet card and some usb 3.0/1G ethernet combo card I bought on Amazon some time ago). Chip supports x4, but the board I use only routed 2 lanes. I'm working on a new PCB which would have several PCIE ports - x1 and x4 via switch for further experiments. I also have a few Zynq030 chips laying around that I've managed to snag for cheap, they will be next once I make that board, as they theoretically allow PCIE 3.0x4 (though I will have to implement it myself as Xilinx only provides IP for 2.0).

One thing is that PCIE switches currently are super expensive and hard to find in stock anywhere. So I will probably have to resort to some shady places to get some, but for a prototype that shouldn't be a big deal.

Navigation

[0] Message Index

[#] Next page

There was an error while thanking
Thanking...
Go to full version