Libreboot 20230625 has been released. The libreboot project offers a free BIOS/UEFI firmware replacement that boots specific Intel/AMD x86 and ARM targets.

Libreboot 20230625 released!

Libreboot provides boot firmware for supported x86/ARM machines, starting a bootloader that then loads your operating system. It replaces proprietary BIOS/UEFI firmware on x86 machines, and provides an improved configuration on ARM-based chromebooks supported (U-Boot bootloader, instead of Google’s depthcharge bootloader). On x86 machines, the GRUB and SeaBIOS coreboot payloads are officially supported, provided in varying configurations per machine. You can find the list of supported hardware in the Libreboot documentation.

Work done since last release

New mainboards now supported:

These boards were added to Libreboot:

• Laptop: HP EliteBook 2570p (courtesy Riku Viitanen)
• Desktop: HP 8300 USDT (courtesy Riku Viitanen, who also ported this to coreboot)
• Desktop: Gigabyte GA-G41M-ES2L was re-added, having been previously deleted from Libreboot.

The focus has been on stability, auditing the build system and fixing bugs, thus hardware support is not greatly improved since the last release. Moving forward, the next Libreboot release will be a testing release and will focus on hardware support in addition to payloads (linux boot, UEFI etc).

No-microcode ROMs available

Since Libreboot 20221214 and up, CPU microcode is included by default on all applicable x86 mainboards. However, Libreboot provided (and still provides) documentation for how to manually remove it.

Such removal is still possible, but this release now provides two sets of ROM images for each x86 mainboard: one set of ROMs will contain CPU microcode, and another set excludes them. For more context, see  Binary Blob Reduction Policy and  Freedom Status.

An earlier article was written about this,  here

Massive build system audit

The full change log below will list all build system changes, but may not provide the overall picture, so to be clear: the Libreboot build system has undergone an intense audit since the last release. Over half of it has been re-written, or heavily re-factored. The logic is much cleaner now (better coding style, based on the OpenBSD coding style) and many bugs are fixed.

An earlier article was written about this,  here

Full list of build system changes

Certain build system changes will not be listed here in detail, if they pertain to general code style cleanup/re-factoring, as already alluded to in the section above. However, specific bug fixes will be listed here, some of which are also referenced in the article linked above.

Newest changes first, oldest changes last:

• Coreboot utilities: build them and place them under cbutils/ from the main lbmk directory. Use these binaries during build (ROM images, for example). this makes handling of coreboot more robust, where we can now run make distclean without worrying about utilities. This also fixes the bug where utilities were being needlessly re-compiled, slowing down the build of multiple ROM images.
• Boot logo size reduced to ~3KB, down from ~12KB. Courtesy Riku Viitanen. This was done, without loss of image quality.
• cros: Disable coreboot-related BL31 features. This fixes poweroff on gru chromebooks. Patch courtesy of Alper Nebi Yasak.
• u-boot: Increase EFI variable buffer size. This fixes an error where Debian’s signed shim allocates too many EFI variables to fit in the space provided, breaking the boot process in Debian. Patch courtesy Alper Nebi Yasak
• Re-added Gigabyte GA-G41M-ES2L mainboard. It actually does boot, but we have always known that raminit is quite experimental on this board. You just have to cycle through RAM until you find modules that work.
• nyan chromebooks: Removed for now (not yet stable) - this release only contains gru chromebooks, where ARM-based chromebooks are concerned.
• blobutil/download: Exit with zero status (success) immediately, when no board configs exist for a specified target. This fixes the ./build boot roms all command, when the relevant script encounters certain targets defined under resources/coreboot, where previously the command would fail due to implicit references to such files.
• Main lbmk script: Exit non-zero if a called script fails, explicitly. The script previously relied on -e which isn’t always completely reliable. The new handling also explicitly prints lbmk error on stdout, to let the operator know that an error did in fact occur.
• Board target t440p_12mb renamed to t440plibremrc_12mb
• build/boot/roms: No-microcode ROM images provided, alongside the default ROMs that include microcode by default. This change is also alluded to in the sections above.
• blobutil/download: Cache downloads based on checksum, to avoid needlessly re-downloading files per mainboard. This is useful when compiling multiple ROM images, for multiple mainboards. Patch courtesy Riku Viitanen.
• Dell Latitude E6400 (board): Fix SD cards (SD cards now work fine). Patch courtesy Nicholas Chin.
• util/nvmutil: Vastly more efficient code (part of the audit, referenced in above).
• util/nvmutil:  unveil now used, in addition to pledge when compiled on OpenBSD.
• util/nvmutil: Hardened pledge calls, when compiled on OpenBSD.
• utils: Properly detect OpenBSD, to test whether pledge should be used.
• board hp8200sff: Add 4MB ROM configs, for internal flashing, patch courtesy of Riku Viitanen.
• Unified all scripts in the main directory of lbmk (build system). All core logic is now a single script, removing needless code repetition.
• download/coreboot fix: Do not needlessly re-download a given coreboot tree, if it was already downloaded.
• Removed help text in certain scripts (unnecessary, can just read docs)
• build/release/roms: Fix error handling inside subshells.
• build/release/src: Fix error handling, previously not handled inside subshells.
• build/ich9utils: Fix error handling (subshells)
• build/descriptors: Fixed error handling (certain errors weren’t handled)
• build/grub: Actually handle errors. Logic was handled in subshells, where greater care is required for error handling. Exit with non-zero status upon any error.
• gitclone: Only delete the old project directory if the new download has succeeded, to avoid, for example, complete purging of files when your internet is down. In such cases, it’s better that the script simply fails and no action is taken. This fix implements such caution.
• blobutil fix: Actually exit with non-zero status (fail) when a called script fails. This previously wasn’t done at all.
• .gitcheck (script): Another bug fix, actually do clean coreboot git credentials, when temporary ones were set, per coreboot tree. This previously was not handled at all. (this script removes the need to manually set git name/email, by setting a temporary one which makes the coreboot build system happy when building ROM images)
• .gitcheck (script): Actually run gitcheck-clean. It wasn’t being executed at all, which screwed up the user’s git credentials in some cases (after running lbmk, you would sometimes commit a patch and find that your name is now lbmkplaceholder).
• util/spkmodem_recv: Also: DEBUG define no longer used. It is now an argument namely -d, which can be passed to the program. The code for debug is now present in any build. Usage: spkmodem-recv -d
• New util: util/spkmodem_recv - imported from coreboot, which in turn forked it originally from GNU GRUB. This is a receiving client for spkmodem, a type of serial console provided via pulses over PC speaker. Libreboot’s version greatly improves the error handling, and it has been re-factored for OpenBSD coding style, to replace the (very horrible) GNU coding style. It is also  pledged in Libreboot’s version. For reference,  here is the GNU version, and  here is coreboot’s version of it. And now to blow your mind,  here is the Libreboot version present in release 20230625. A very much GNU program, but you wouldn’t know it by looking! This fork was mostly done for fun, very much a because we can affair. BONUS: BSD-style error handling (err.h)
• download/coreboot: Run extra.sh directly from the directory for the given coreboot tree, if the script exists. No board in Libreboot has ever included an extra.sh script, but it can be used to extend the default functionality of lbmk where lots of custom logic is needed for a given board. For example, if you needed to apply lots of patches from gerrit in a specific order, in a way that could not be generalised for other mainboards where it’s really only applicable to that mainboard, you might use extra.sh. This was briefly used in the erstwhile osboot project, on a few boards.
• download/coreboot: Use the gitclone script for actually cloning coreboot, while still using the main script for handling trees/revisions and such. (this is one of the scripts that got re-written during the audit, mentioned in the previous section above)
• build/payload/seabios: Much stricter error handling, exit with non-zero status (fail) on more error conditions, should they occur.
• download/mrc (script): Much stricter error handling, exit with non-zero status (fail) on more error conditions, should they occur.
• gitclone (script): Check whether a given patch exists before applying. Works around a quirk in most shells where * will error out if no files exist.
• download/grub (script): If downloading gnulib fails, scrap the grub download aswell, and exit with non-zero status (fail). This is done because gnulib is a dependency of GRUB.
• blobutil/inject (script): When inserting gbe.bin, check that the file actually exists, and exit with non-zero status (fail) otherwise.
• blobutil/inject (script): When inserting me.bin, check that the given path is defined and exit with non-zero status (fail) otherwise.
• blobutil/inject (script): Use x86 top-aligned MRC offset, when inserting mrc.bin on Haswell ROM images (ThinkPad T440p/W541). Previously, lbmk would insert them based on the offset as per ROM image file size, but it is possible (and more reliable) to have cbfstool calculate that position within the file based on where the ROM image would be loaded into memory. The result is identical in practise (same checksum for the file), but this is more robust for a future scenario where, for example, Libreboot might provide different sized images. For example, if the flash were upgraded to 16MB rather than 12MB on a T440p (Libreboot still only provides 12MB images for T440p).
• Coreboot build system: patch it to no longer warn about lack of payload when building (patch courtesy of Nicholas Chin). Libreboot’s build system is designed to build ROM images without a payload, and then compile/add payloads itself, as opposed to using the coreboot build system for payloads.
• Don’t patch the build system for python2 anymore. Prefer python3, and use it exclusively. No more python2 code was needed anymore, in lbmk’s dependencies.
• build/boot/roms (script): Fix faulty variable expansion for list of keymaps. This fixes keymap handling when generating GRUB payloads for each keymap.
• The entire build system: massive code cleanup as alluded to above.
• Coreboot: Patched the coreboot device tree on Dell Latitude E6400, so that the Nvidia GPU can be initialised properly (patch courtesy Nicholas Chin) - only Intel GPU variants of E6400 are officially supported in this release.
• SeaBIOS payload: Provide normal config for setups where no VGA ROM init from CBFS is provided, either in SeaBIOS or GRUB(via coreboot). This would be used, for example, on desktops that lack onboard graphics, where it is expected that a graphics card would be used.
• Fixed the Makefile to match current commands available in lbmk (use of the Makefile is still optional, and direct use of lbmk is still recommended)
• Patched util bios_extract to work nicely with Dell E6400 update files, patch courtesy of Nicholas Chin.
• New util: bios_extract (used to VGA ROM from Dell updates, for Nvidia GPU model of Dell Latitude E6400, though this release only officially supports the Intel GPU variant)
• Fixed unifont package info in Fedora 38 dependencies script
• util/e6400-flash-unlock: Minor code cleanup
• Don’t force console mode in GRUB (reverses experimental change made in the 20230423 release)

Libreboot – Libreboot 20230625 released!