Expo is U-Boot’s forms and UI subsystem. It supports text, images and menus and a large expo can contain quite a bit of information. How do you debug and understand that? Tracing through large, linked data structures is not fun. U-Boot Concept now has an expo_dump() function, designed to be called from your code when…
Testing boot scenarios in very important but there are quite a lot of them! Concept currently has about 13 images containing various partitions and files used by the bootstd tests. These are listed in test.dts, for example: All images are built by test_ut_dm_init_bootstd(), but most of these are disabled by default, to avoid making sandbox…
U-Boot’s ‘expo’ toolkit is used for creating user interfaces, such as the configuration editor (cedit) and graphical boot menus (bootflow menu). Previously, user interaction with expo scenes was limited to the keyboard. A recent 23-patch series introduces support for mouse and touchpad interaction. New Input Handling For devices where a mouse or touchpad is available,…
The U-Boot EFI application is a powerful tool, allowing U-Boot to run on top of existing UEFI firmware. This is increasingly important as we see new platforms, especially in the ARM64 world, shipping with complex, ACPI-based firmware. A prime example is the recent wave of laptops powered by the Qualcomm X-Elite, which rely on this…
If you are interested in watching the development of U-Boot Concept, consider joining the mailing list. You can do this in your web browser here, or send an email with ‘subscribe’ in the subject to concept-join@u-boot.org. If you are able to review patches or contribute your own, please do! Also the patchwork server is up and…
We’ve just merged a fix in Concept for a particularly tricky memory corruption bug in the U-Boot sandbox environment. This bug was difficult to track down, so we wanted to share the story of the investigation and the solution. The Symptom: Mysterious Heap Corruption The problem first appeared as random and hard-to-reproduce memory corruption in…
Continuous Integration (CI) is the backbone of a large project like U-Boot, ensuring that every change is tested against a huge matrix of boards and configurations. While this comprehensive testing is vital for quality, it can also be time-consuming. When you’re focused on a specific feature, waiting for a full “world build” to complete can…
As U-Boot’s support for hardware grows, so does the complexity of managing build configurations. A single board might require several build variations—for example, one with network support and one without, or a standard build versus one tailored for Android booting. Historically, managing these variations often meant duplicating large defconfig files, a maintenance headache waiting to…
Since 2018 U-Boot has had a good selection of features for running on top of QEMU, including: Most of this was written by Bin Meng. It uses driver model and is nicely implemented. What’s new? More recently a few more features have been added: The `virtio list` command can be useful for seeing what paravirtualised…
What is virtio-fs? For those unfamiliar, virtio-fs is a modern shared filesystem designed specifically for virtualised environments. It allows a virtual machine (the “guest”) to access a directory on the host system, but it does so with a focus on performance and providing local filesystem semantics. Unlike traditional methods like network filesystems (e.g., NFS, Samba)…
