Posts

Showing posts from 2010

Prolonging the battery life on your laptop/netbook running Ubuntu

mdz pointed me to Idea 24782 over at Ubuntu Brainstorm that urges the Ubuntu community to increase focus on making Ubuntu run longer on devices with batteries. I support the idea wholeheartedly. Since the advent of laptops and netbooks, users have wanted to stretch the battery to last that extra 15 minutes it'll require for them to finish up their email or their documents. In fact, the most popular idea ever on Brainstorm is about fixing suspend and hibernate. Unfortunately, it ended up becoming a whirlpool of several different ideas, albeit with a common theme - making the battery last longer . There are several things that can be done to make the battery on a mobile device last longer - some under user control, others under OS/firmware control and some others dependent on HW capabilities. I am going to attempt to summarize the various use profiles and what Ubuntu does (or can do) to prolong battery life in those profiles. Power management, when done right, should not requi

cross-compilation re-redux

Sigh! I don't think I'm going to get the cross-compilation article right, ever! The repository has now moved to a Launchpad PPA . So, for Maverick, you can do the following: sudo apt-add-repository ppa:hrw/arm-cross-compiler sudo apt-get update sudo apt-get install gcc-arm-linux-gnueabi g++-arm-linux-gnueabigcc Eventually, the idea is to replace this PPA as well, because the cross-compiler will be available in Ubuntu.

cross-compilation redux

It has been a while since my last blog post about developing for ARM platforms. We last looked at how to cross-compile the kernel. It is time to revisit that recipe. Linaro I've been working with Linaro for the last few months to improve the toolchain, kernel and other components of Linux plumbing on ARM. There is also work to refactor the partner BSPs so that they can co-exist peacefully i.e. single kernel source tree, single u-boot tree, etc. We're just getting started but you can see the status for the first Linaro release in November. Cross-compile toolchains One of the first things that an embedded project has had to do is roll their own toolchain. This is obviously wasted time and effort. Linaro is attempting to fix this problem by pushing fixes into gcc upstream and by providing a standard toolchain for ARM development. This toolchain will take advantages of features of the ARMv7 architecture (NEON acceleration, various performance optimisations, SMP support, etc.).