Measuring and Improving Software Energy Consumption

Measuring and Improving Software Energy Consumption

Introduction In a world where data centers consume nearly 1% of global electricity, optimizing the energy consumption of computer systems has become a critical priority. In 2022, the electricity consumption of data centers reached 460 TWh and could exceed 620 TWh by 2026 (source). A low hanging fruit is software improvement: can we reduce the carbon footprint of our code? This article will guide you through various methods of measuring energy consumption of your code, enabling you to better understand…

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Program the DE1-SoC’s FPGA from Linux using Device Tree overlay

When using a SoC-FPGA (SoC coupled with an FPGA for programmable logic) such as the DE1-SoC from Terasic, programming the FPGA can be performed in many different ways: Directly from an FPGA software (Quartus for example) From U-boot before launching the OS From the OS Using this last option allows the FPGA to be reconfigured without having to reboot the OS and with the adequate support, even allows the OS to reconfigure itself to use the newly programmed features of…

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Automated C/C++ Build through GitHub Actions

Have you been wondering how some projects add a small badge to their README that shows the project build status ? Well we will show how to set this up on GitHub. First this is documented in the official GitHub documentation : and here However, the documentation may seem a bit daunting at first, so let’s make an easy to follow tutorial. Setting up a build workflow For this I will show how to build a very simple…

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Tux by Iwan Gabovitch (gg3po) Licensed under GPLv2

Linux kernel hacking on ZynqUltraScale+ with Petalinux

The ZynqUltraScale+ is a powerful SoC platform combining multi-core ARM64 CPUs and FPGA technology. There are plenty of projects that can take advantage of running a Linux kernel on the ARM64 processor and sometimes they require some degree of kernel hacking. In this post we will setup a build environment to modify the Linux kernel, compile it, and run it rapidly on a ZCU106 development board. For this we want the following : Be able to modify and compile the…

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An ARM single board computer as PCIe card !?! (part 2) a Linux based NVMe drive !

In the previous post we prepared a setup with a FriendlyElec NanoPC-T4 single board computer (SBC) we connected it through PCIe to a host computer. This time we will setup a Pine64 Rockpro64 board which comes with a more convenient PCIe 4x female edge connector instead of an M.2 slot. Both boards are based on the same Hexa-Core Rockchip RK3399 chip. In this post we will explore how to build a custom Linux kernel and load a PCIe endpoint function…

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An ARM single board computer as PCIe card !?! (part 1)

In this blog post series I will show how we can use an ARM single board computer (SBC) as a PCIe card (PCIe endpoint). At REDS when developing PCIe based devices we usually rely on FPGAs, for example to develop FPGA PCIe accelerators. These are often based on existing PCIe cards from AMD (Xilinx) and Intel (Altera). For example the Xilinx Alveo series or Zynq based development boards. To develop accelerators such cards are fine and the development boards allow…

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Tux by Iwan Gabovitch

How to apply patches from the Linux Kernel Mailing List

The Linux Kernel is under constant development and improvement. Everyday patches are submitted to the Linux Kernel Mailing List (LKML). Some of these patches get accepted and merged into the mainline Linux kernel and become available to the user, other patches never do. Sometimes it is useful to get patches from the LKML, for example if you are developing in the kernel or simply because you want to stay at the bleeding edge. Another reason could be that you need…

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FreeRTOS + POSIX on Zynq

FreeRTOS is a popular free and open-source real-time operating system (RTOS) for embedded platforms. It has its own scheduler, tasks, and synchronisation primitives. Writing concurrent applications for FreeRTOS requires to learn the environment and make use of the provided tools. In some cases, a developper might want to port an existing concurrent application written with POSIX interfaces (such as pthreads, semaphores, message queues, etc.). Usually there are two approaches here : Convert everything to FreeRTOS primitives. Write an OS abstraction…

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NVMe emulation in QEMU – Adding custom admin and IO commands

QEMU is a wonderful system emulator capable of running full x86 systems with PCIe and NVMe amongst many other platforms. QEMU is not only versatile, very fast, but also open-source ! At REDS we use QEMU to facilitate development of hardware through emulation, for example emulating FPGA platforms in software before going to real hardware, e.g., Full System Simulation (FSS), Zynq Software-Hardware CoSimulation. The full visibility over the system through emulation make development and debugging very effective. With a QEMU…

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eclipse for nRF5 SDK installation guide

Introduction nRF5 SDK allows the development of software for the nRF51 and nRF52 SoCs. Nordic Semiconductor promotes the use of the nRF Connect SDK, but I found it complex to use because it doesn’t allow bare metal (it works with the RTOS Zephyr Project) and force you to use new tools like DeviceTree and CMake that I’m not proficient with. Nordic Semiconductor offers a free license to SEGGER Embedded Studio for development with nRF chips, but if you are like…

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About This Site

Technical articles related to the development work performed at the REDS institute, HEIG-VD (Switzerland).

The REDS institute is part of the High School of Engineering, Vaud. Its core skills involve board conception, firmware development and FPGA programming.

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