limine/CONFIG.md

3.8 KiB

Limine configuration file

The Limine configuration file is comprised of assignments and entries.

Entries describe boot entries which the user can select in the boot menu.

An entry is simply a line starting with : followed by a newline-terminated string. Any locally assignable key that comes after it, and before another entry, or the end of the file, will be tied to the entry.

Assignments are simple KEY=VALUE style assignments. VALUE can have spaces and = symbols, without requiring quotations. New lines are delimiters.

Some assignments are part of an entry (local), some other assignments are global. Global assignments can appear anywhere in the file and are not part of an entry, although usually one would put them at the beginning of the config. Some local assignments are shared between entries using any protocol, while other local assignments are specific to a given protocol.

Some keys take URIs as values; these are described in the next section.

Globally assignable keys are:

  • TIMEOUT - Specifies the timeout in seconds before the first entry is automatically booted.
  • DEFAULT_ENTRY - 0-based entry index of the entry which will be automatically selected at startup. If unspecified, it is 0.
  • GRAPHICS - If set to yes, do use graphical VESA framebuffer for the boot menu, else use text mode.
  • THEME_COLOURS - Specifies the colour palette used by the terminal (AARRGGBB). It is a ; separated array of 8 colours: black, red, green, brown, blue, magenta, cyan, and gray, respectively. Ignored if GRAPHICS is not yes.
  • THEME_COLORS - Alias of THEME_COLOURS.
  • THEME_MARGIN - Set the amount of margin around the terminal. Ignored if GRAPHICS is not yes.
  • THEME_MARGIN_GRADIENT - Set the thickness in pixel for the gradient around the terminal. Ignored if GRAPHICS is not yes.
  • BACKGROUND_PATH - URI where to find the background .BMP file. Ignored if GRAPHICS is not yes.

Locally assignable (non protocol specific) keys are:

  • PROTOCOL - The boot protocol that will be used to boot the kernel. Valid protocols are: linux, stivale, stivale2, chainload.
  • CMDLINE - The command line string to be passed to the kernel. Can be omitted.
  • KERNEL_CMDLINE - Alias of CMDLINE.

Locally assignable (protocol specific) keys are:

  • Linux protocol:

    • KERNEL_PATH - The URI path of the kernel.
    • MODULE_PATH - The URI path to a module (such as initramfs).

    Note that one can define this last variable multiple times to specify multiple modules.

  • stivale and stivale2 protocols:

    • KERNEL_PATH - The URI path of the kernel.
    • MODULE_PATH - The URI path to a module.
    • MODULE_STRING - A string to be passed to a module.

    Note that one can define these 2 last variable multiple times to specify multiple modules. The entries will be matched in order. E.g.: the 1st module path entry will be matched to the 1st module string entry that appear, and so on.

  • Chainload protocol:

    • DRIVE - The 1-based BIOS drive to chainload.
    • PARTITION - The 1-based BIOS partition to chainload, if omitted, chainload drive.

URIs

A URI is a path that Limine uses to locate resources in the whole system. It is comprised of a resource, a root, and a path. It takes the form of:

resource://root/path

The format for root changes depending on the resource used.

A resource can be one of the following:

  • bios - The root takes the form of drive:partition; for example: bios://3:1/... would use BIOS drive 3, partition 1. Partitions and BIOS drives are both 1-based. Omitting the drive is possible; for example: bios://:2/.... Omitting the drive makes Limine use the boot drive.
  • guid - The root takes the form of a GUID/UUID, such as guid://736b5698-5ae1-4dff-be2c-ef8f44a61c52/.... It is a filesystem GUID and not a partition GUID.