ChromeOS now runs on top of Linux and Zephyr • The Register

Column You most likely knew Google’s ChromeOS is a Linux distribution. However, now, it is working on greater than Linux beneath the hood. I did not, and I have been overlaying Chrome OS like paint because the day it arrived. At this time, your newer Chromebook additionally is determined by the open-source Zephyr Project Real-Time Operating System (RTOS). This is Chrome OS’s historical past and the place Zephyr is available in. 

Initially, ChromeOS’s beginnings have been shrouded in thriller. Jeff Nelson, a former Google engineer, claimed that he created “Google OS,” an ancestor to Chrome OS, which used Firefox as its browser, though it’s a matter of dispute whether or not this venture is linked to the working system we all know in the present day.

Antoine Labour, “one of many three authentic engineers on the venture,” stated Nelson’s venture and the eventual Chrome OS have been completely different endeavors. 

Labour has stated that the “Chrome OS venture itself, the one which ended up rising and truly shipped merchandise, didn’t exist in 2006.”

There’s clearer proof that ChromeOS sprang from Ubuntu Linux in November 2009, with Canonical, Ubuntu’s mum or dad firm, serving to to construct the now ubiquitous OS.

As Chris Kenyon, then Canonical’s VP of OEM Companies, wrote, “Canonical is contributing engineering to Google under contract. In our discussions, Sundar Pichai [Google’s senior vice president of Chrome] and Linus Upson [Google’s VP of engineering for Chrome] made it clear that they need, wherever possible, to construct on present parts and instruments from the open-source neighborhood with out pointless re-invention.”

However, ChromeOS would not keep based mostly on Ubuntu. In February 2010, Chrome OS switched from Ubuntu to Gentoo Linux. Sure, that is proper, the Linux nerd’s hardcore distribution for a few years underlaid the simplest Linux distro. Who knew? (Nicely, in addition to Gentoo customers, ChromeOS builders, and me.)

This was accomplished, as recorded in a Chromium OS developer e-mail record dialogue, as a result of  “the need to support board-specific builds and improve our tools has become more urgent. To be able to get there extra rapidly, we have been investigating a number of completely different construct instruments. We discovered that the Portage construct instruments to swimsuit our wants properly, and we will likely be transitioning one hundred pc inside the subsequent week.” Portage, for these of you who aren’t Gentoo customers, compiles packages immediately from supply code. 

However, ChromeOS would not keep on Gentoo both. Whereas Portage continued for use for bundle administration, newer ChromeOS variations are based mostly on a Google-customized Linux kernel. At this time it is also working on Zephyr. 

This occurred in July of 2021 when Chromebooks switched from the unique Google Chrome Embedded Controller (EC) to at least one based mostly on Zephyr. Your newer Chromebook is not working, nevertheless, on vanilla Zephyr. It is working on a ChromeOS Zephyr fork. 

Why? First, Google desires Chromebooks to be as safe as doable. As Puneet Kumar, then Google’s Chrome OS Director of Engineering, stated in 2020, “Google believes in building secure products for all of our customers, and we’re excited to hitch forces with Zephyr to develop a safe real-time working system.”

Since then, Zephyr has been in charge of the embedded controller (EC). That is an always-on ultra-low-power microcontroller. It handles every thing you desire a Chromebook to do when the applying processor is off or sleeping. Particularly, the EC is important for extending the Chromebook’s battery life.

One motive you most likely did not hear about this swap is that ChromeOS builders do not have to fret about it. The EC’s utility programming interfaces (API) remained unchanged. So no matter whether or not a Chromebook makes use of the unique EC code or the newer Zephyr-based EC code, ChromeOS functions run the identical as ever. 

In addition to being an RTOS, Zephyr can be a small, scalable working system that is excellent to be used on resource-constrained programs over a number of architectures. That makes it simpler and sooner for Google and its Chromebook companions to maneuver to new architectures and assist new tools drivers. 

Who is aware of? Possibly we’ll see a RISC-V-powered Chromebook: the CPU assist’s in there. ®