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% Binary Blob Reduction Policy % Leah Rowe % 4 January 2022 (updated 15 November 2022)

Introduction

This article describes the principles that govern the Libreboot project. For information about how those principles are applied in practise, please read this article instead: Software and hardware freedom status for each mainboard supported by Libreboot

Libreboot's policy is to provide as much software freedom as possible to each user, on each and every bit of hardware supported, and to support as much hardware from coreboot as is feasible; what this means is that you should have the potential to study, modify and share all source code, documentation or other such resources that make Libreboot what it is. Put simply, you should have control of your own computing.

The goal of Libreboot is to do exactly this, and help as many people as possible by automating the configuration, compilation and installation of coreboot for non-technical users, easing it further for the average user by providing user-friendly instructions for everything. Essentially, Libreboot is a coreboot distribution, in much the same way Alpine Linux is a Linux distribution!

The purpose of this document it to outline how that is brought about, and how the project operates along this basis. This document is largely about the ideology and it is therefore (mostly) non-technical; for technical information, you can refer to the Libreboot build system documentation.

Current project scope

The libreboot project is concerned with what goes in the main boot flash IC, but there are other pieces of firmware to take into consideration, as covered in the libreboot FAQ.

Most critical of these are:

Embedded controller firmware
HDD/SSD firmware
Intel Management Engine / AMD PSP firmware

What is a binary blob?

A binary blob, in this context, is any executable for which no source code exists, that you cannot study and modify in a reasonable manner. By definition, all such blobs are proprietary in nature, and should be avoided if possible.

For information about Intel Management Engine and AMD PSP, refer to the FAQ.

Blob reduction policy

Default configurations

Coreboot, upon which Libreboot is based, is mostly libre software but does require certain vendor code on some platforms. A most common example might be raminit (memory controller initialisation) or video framebuffer initialisation. The coreboot firmware uses certain vendor code for some of these tasks, on some mainboards, but some mainboards from coreboot can be initialised with 100% libre source code, which you can inspect, and compile for your use.

Libreboot deals with this situation in a strict and principled way. The nature of this is what you're about to read.

The libreboot project has the following policy:

If free software can be used, it should be used. For example, if VGA ROM initialization otherwise does a better job but coreboot has libre init code for a given graphics device, that code should be used in libreboot, when building a ROM image. Similarly, if memory controller initialization is possible with vendor code or libre code in coreboot, the libre code should be used in ROMs built by the Libreboot build system, and the vendor raminit code should not be used; however, if no libre init code is available for said raminit, it is permitted and Libreboot build system will use the vendor code.
Some nuance is to be observed: on some laptop or desktop configurations, it's common that there will be two graphics devices (for example, an nvidia and an intel chip, using nvidia optimus technology, on a laptop). It may be that one of them has libre init code in coreboot, but the other one does not. It's perfectly acceptable, and desirable, for libreboot to support both devices, and accomodate the required vendor code on the one that lacks native initialization.
An exception is made for CPU microcode updates: they are permitted, and in fact required as per libreboot policy. These updates fix CPU bugs, including security bugs, and since the CPU already has non-libre microcode burned into ROM anyway, the only choice is either x86 or broken x86. Thus, libreboot will only allow coreboot mainboard configurations where microcode updates are enabled, if available for the CPU on that mainboard. Releases after 20230423 will provide separate ROM images with microcode excluded, alongside the default ones that include microcode.
Intel Management Engine: in the libreboot documentation, words must be written to tell people how to neuter the ME, if possible on a given board. The me_cleaner program is very useful, and provides a much more secure ME configuration.
Vendor blobs should never be deleted, even if they are unused. In the coreboot project, a set of 3rdparty submodules are available, with vendor code for init tasks on many boards. These must all be included in libreboot releases, even if unused. That way, even if the Libreboot build system does not yet integrate support for a given board, someone who downloads libreboot can still make changes to their local version of the build system, if they wish, to provide a configuration for their hardware.

Generally speaking, common sense is applied. For example, an exception to the minimalization might be if vendor raminit and libre raminit are available, but the libre one is so broken so as to be unusable. In that situation, the vendor one should be used instead, because otherwise the user might switch back to an otherwise fully proprietary system, instead of using coreboot (via libreboot). Some freedom is better than none.

Libreboot's pragmatic policies will inevitably result in more people becoming coreboot developers in the future, by acting as that crucial bridge between it and non-technical people who just need a bit of help to get started.

Configuration

The principles above should apply to default configurations. However, libreboot is to be configurable, allowing the user to do whatever they like.

It's natural that the user may want to create a setup that is less libre than the default one in libreboot. This is perfectly acceptable; freedom is superior, and should be encouraged, but the user's freedom to choose should also be respected, and accomodated.

In other words, do not lecture the user. Just try to help them with their problem! The goal of the libreboot project is simply to make coreboot more accessible for otherwise non-technical users.

FREEDOM CATALOG

A freedom status page should also be made available, educating people about the software freedom status on each machine supported by the Libreboot build system. Please read: Software and hardware freedom status for each mainboard supported by Libreboot.

It is desirable to see a world where all hardware and software is libre, under the same ideology as the Libreboot project. Hardware!?

Yes, hardware. RISC-V is a great example of a modern attempt at libre hardware, often called Open Source Hardware. It is a an ISA for the manufacture of a microprocessor. Many real-world implementations of it already exist, that can be used, and there will only be more.

Such hardware is still in its infancy. We should start a project that will catalog the status of various efforts, including at the hardware level (even the silicon level). Movements like OSHW and Right To Repair are extremely important, including to our own movement which otherwise will typically think less about hardware freedoms (even though it really, really should!)

One day, we will live in a world where anyone can get their own chips made, including CPUs but also every other type of IC. Efforts to make homemade chip fabrication a reality are now in their infancy, but such efforts do exist, for example, the work done by Sam Zeloof and the Libre Silicon project:

(Sam literally makes CPUs in his garage)

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