Intel FPGA’s Stratix 10: My impressions and notes

Introduction These are a few random things I wrote down as I worked with the Stratix 10 Development Kit, with focus on its PCIe interface. Quite obviously, it’s mostly about things I found noteworthy about this specific FPGA and its board, compared with previous hardware I’ve encountered. Generally speaking, Stratix 10 is not for the [...]

Intel Stratix 10 PCIe IP: Building it only appears to be stuck

These are a few notes when implementing an FPGA design for Stratix 10 with a Makefile flow (i.e. command-line utilities) with Quartus 19.2. So I wanted was to implement a design including the PCIe 16x block for Stratix 10. I added a line going set_global_assignment -name IP_FILE pcie_s10_16x.ip in the relevant QSF file. And by [...]

Intel / Altera: Proper access of the Configuration Space Registers (tl_cfg_ctl)

Introduction The PCIe blocks on Intel (formerly Altera) FPGAs have a somewhat peculiar, yet useful interface for exposing some of the interface’s configuration information, called “Transaction Layer Configuration”. For the purposes of this post, it consists of two output signals, tl_cfg_add[3:0] and tl_cfg_ctl[31:0]. Both are driven by the PCIe block, and clocked by the same [...]

Quartus: The importance of derive_pll_clocks in the SDC file

Introduction Whenever a PLL is used in a design to generate one clock from another, it’s quite common to expect the timing tools to figure out the frequencies and timing relations between the different clocks. With Intel’s Quartus tools, this isn’t the case by default. A derive_pll_clocks command is required in the SDC constraints file [...]

PCIe on Cyclone 10 GX: Data loss on DMA writes by FPGA

TL;DR DMA writes from a Cyclone 10 GX PCIe interface may be lost, probably due to a path that isn’t timed properly by the fitter. This has been observed with Quartus Prime Version 17.1.0 Build 240 SJ Pro Edition, and the official Cyclone 10 GX development board. A wider impact is likely, possibly on Arria [...]

Quartus / Linux: Programming the FPGA with command-line

Command-line? Yes, it much more convenient than the GUI programmer. Programming an FPGA is a repeated task, always the same file to the same FPGA on the same board connected to the computer. And somehow the GUI programming tools turn it into a daunting ceremony (and sometimes even a quiz, when it can’t tell exactly [...]

Quartus / sdc: Constraining I/O ports clocked by an internal clock

Introduction This post is an expansion for another post of mine, which deals with register I/O packing. It’s recommended reading that one first. Timing constraining of I/O ports is typically intended to ensure timing relations between an external clock and the timing of signals that are clocked by this clock (or derived from this clock, [...]

Cyclone V and some transceiver CDR/PLL parameters

Introduction Connecting an Intel FPGA (Altera) Cyclone V’s Native Transceiver IP to a USB 3.0 channel (which involves a -5000 ppm Spread Spectrum modulation), I got a significant bit error rate and what appeared to be occasional losses of lock. Suspecting that the CDR didn’t catch up with the frequency modulation, I wanted to try [...]

Quartus, timing closure: Obtaining a concise multi-corner timing path report

Introduction The natural thing to do when an FPGA design fails timing is to take a detailed look at the critical paths, based upon a timing report showing the logic elements and their delays of this path. If you’re not a heavy user of Intel’s FPGAs (a.k.a. Altera), it may not be so trivial to [...]

Making any IP in the IP Catalog availabe in QSys

Introduction I needed the Cyclone V Transceiver Native PHY IP Core inside QSys. Why? Actually, part of a failed attempt to find solve a compilation error. The IP is available in Quartus 15.1′s IP Catalog, but inside the same toolkit’s QSys it doesn’t appear in the list of IPs. As discussed in this forum thread, [...]