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title: BSD operating systems x-toc-enable: true ...
This section is largely x86-centric, pertaining to use of BSD operating systems. Although not as popular, BSD systems are also (in most cases) Free Software, but they are non-copyleft.
Libreboot is capable of booting many BSD systems. This section mostly documents the peculiarities of Libreboot as it pertains to BSD; you can otherwise refer to the official documentation for whatever BSD system you would like to use.
Video modes
For BSD systems, it is desirable that you boot in text mode. ROM images
with txtmode in the file name, on x86 systems, boot up with int10h text mode
in use. This is the most "compatible" option, and BSD operating systems have
excellent support for text-mode startup. Many of them also support kernel mode
setting (KMS) nowadays, which you need if you want a graphical desktop on
the X window system. The reason is that Libreboot does not currently implement
int10h VGA modes on x86 systems. However, basic video initialization is
provided on all platforms (int10h text mode, or coreboot framebuffer).
Combined with the use of SeaBIOS payload, BSD systems (and any other OS that can boot in text mode) will just work. If your BSD system supports kernel mode setting, it can set up a framebuffer without making use of int10h VGA modes. In this case, the driver (e.g. Intel video driver) will set modes directly, and implement its own framebuffer.
Booting with a coreboot framebuffer will also work well on most BSD systems.
These ROM images have corebootfb in the filename, on recent Libreboot releases.
In this setup, you should make sure that your BSD system has a corebootfb
driver (to make use of the coreboot framebuffer), but when switching to X, your
video driver (e.g. Intel video driver) may already support kernel mode setting
which means that the coreboot framebuffer will no longer be used at that point.
Booting BSD
On x86 platforms, Libreboot currently provides the choice of GNU GRUB and/or SeaBIOS payload. You can use either payload, to boot BSD operating systems.
SeaBIOS payload
It is highly recommended that you use the SeaBIOS payload. ROM images are available in the latest Libreboot release, which start with the SeaBIOS payload.
The ROM images with GNU GRUB also have SeaBIOS available in the boot menu.
GNU GRUB, when compiled as a coreboot payload, runs on bare metal and it can
boot any other coreboot payload if you use the chainloader command.
The way to use SeaBIOS is fairly self-explanatory. SeaBIOS functions the way you would expect on a typical computer. Libreboot currently lacks any sort of documentation for SeaBIOS, but you can refer to their website: https://seabios.org/SeaBIOS
SeaBIOS is especially recommended if you're doing an encrypted installation.
The benefit to using SeaBIOS is that it's basically more reliable. For example, ZFS support is less reliable in GRUB, but a FreeBSD system booted in SeaBIOS would work just fine because you'd be using FreeBSD's own bootloader in that instance.
GNU GRUB payload
GRUB can directly boot many BSD kernels, but support for this is quite unreliable compared to its support for booting Linux kernels. However, you can use GRUB.
When you use GNU GRUB directly, in this way, the various BSD bootloaders are bypassed entirely.
We have separate pages for each BSD system: