The Linux kernel feature known as ‘kexec‘ allows you to boot from the currently running kernel into a new kernel – effectively turning a Linux distribution into a feature-rich bootloader. This shouldn’t be confused with virtualisation technologies that allow you to run Linux as a guest. This capability has been around since 2005 (2.6.13) and …
Year: 2020
A Global Variable in U-Boot that caused a Hang
The best type of software bug is one where you get to learn something along the way. Like any good disaster, the bug we’re going to explore is one that arose from a chain of unexpected events and bad assumptions. This bug relates to uninitialised data and gives a good insight into the inner workings …
Multiple UVC cameras on Linux: an unexpected challenge
Earlier this year one of our customers presented us with an unexpected problem: they weren’t able to stream video from multiple USB UVC web cameras – instead they got a “No space left on device” error. In our quest to provide a solution we learnt a little about USB and so we thought we’d share …
Xmas Charity Fundraiser 2020
This Xmas the Good Penguin is raising money for Sparkle, a charity in our local community that supports children, young people, and their families, with disabilities and/or developmental difficulties. Verity Cadwallader, a corporate fundraiser at Sparkle tells us, “We support over 300 families per week through delivering activities and clubs such as independent living skills, …
Build and Boot U-Boot and Linux on a Raspberry Pi 3 Model B+
With more than 30 million units in existence, the Raspberry Pi provides for an accessible and low-cost way to play with an ARMv8 embedded device using the latest and greatest upstream sources. In this post we’ll walk through the steps required to build U-Boot, the Linux kernel and a filesystem, as well as the steps …
i.MX6 UL Bus Encryption Engine (BEE) in the Linux Kernel
The ubiquitous i.MX6 Ultra Lite is high performance processor that offers a wide range of hardware security features such as ARM TrustZone, High Assurance Boot (HAB) and a Cryptographic Acceleration and Assurance Module (CAAM). The exact features and details depend on the specific part and are documented in detail in the Security Reference Manual (locked …