Boot configuration

The UniXNU boot manager reads \EFI\UniXNU\unixnu.toml from the volume it was started from, then from every other volume. A kit directory contains Kit.toml with the same match and injection sections.

unixnu.toml

version = 1

[boot]
timeout = 5
rotate = 0
fallback_timeout = 10
connect_all = true
default = "xnu"

[ui]
title = "UniXNU"
scale = 0
logo = true
console = "auto"

[boot]

Key	Default	Meaning
timeout	5	Seconds. Negative waits for input
rotate	0	Idle highlight rotation in seconds. 0 disables it
fallback_timeout	10	Timeout when no input device exists
connect_all	true	Calls ConnectController on every handle
default	first entry	Entry id or index

[ui]

Key	Default	Meaning
title	UniXNU	Menu title
scale	0	Glyph scale. 0 selects automatically
logo	true	Draws the logo
console	auto	auto, graphics, text or none

[[driver]]

[[driver]]
path = "Drivers/MyDriver.efi"
args = "board=1"
connect = true
enabled = true

Key	Default	Meaning
path	required	File path or fv:<GUID>
args		Load options
connect	true	Connects controllers after the driver starts
enabled	true	false skips the entry

A kit driver uses file instead of path.

[[dt_patch]]

[[dt_patch]]
op = "set"
node = "/chosen"
prop = "bootargs"
value = "console=ttyAMA0"
type = "string"

Key	Meaning
op	set, delete-prop, add-node, delete-node or overlay
node	Absolute node path
prop	Property name for set and delete-prop
value	Value for set
type	string, stringlist, u32, u64, bytes or empty
file	Overlay file for overlay

Patches apply to EFI and Linux entries. The Darwin path uses the .adt sidecar.

[[block_slice]]

[[block_slice]]
partition = "<GPT name>"
name = "<slice name>"
offset = 0
length = 0
writable = false
enabled = true

Key	Meaning
partition	GPT partition name
name	Label in the device path
offset	Byte offset from the partition start
length	Byte length. 0 means to the end
writable	Publishes a writable block device
enabled	false skips the slice

The slice appears as a whole disk with its own device path. A child partition scheme or file system driver can bind to it.

ACPI

[acpi]
add = ["Tables/DSDT.aml", "Tables/SSDT.aml"]

Each table is installed through EFI_ACPI_TABLE_PROTOCOL. The header length must match the file size.

Kits

[[kit]]
path = "Kits/MyKit.kit"
enabled = true

[kits]
autoload = true
directory = "Kits"

Explicit kits load first. With autoload, every *.kit directory under directory loads in name order.

[[entry]]

[[entry]]
id = "xnu"
title = "UniXNU"
type = "xnu"
path = "Payloads/kernel.macho"
args = "-v serial=3"
initrd = "Payloads/scratch-data.img"
enabled = true

Key	Meaning
id	Entry identifier
title	Menu title
type	efi, linux, action or xnu
path	EFI image, Linux image or kernel path
args	Load options or kernel command line
dtb	firmware, a file path, or absent
initrd	Initrd path
action	reset, shutdown or exit for action entries
enabled	false skips the entry

The built-in configuration has exit, reset and shutdown entries. When no file is found, removable loaders are added in front of them.

[entry.chosen]

[entry.chosen]
bootargs = "console=ttyAMA0"

Every key becomes a /chosen property. These patches apply after the entry patches.

[[entry.kext]]

[[entry.kext]]
bundle = "Kexts/MyDriver.kext"
plist = "Contents/Info.plist"
executable = "Contents/MacOS/MyDriver"
enabled = true

Entry kexts apply only to the entry that declares them.

[[entry.variable]]

[[entry.variable]]
guid = "00000000-0000-0000-0000-000000000000"
name = "MyVariable"
value = "hello"
type = "ascii"
volatile = true

Key	Meaning
guid	Variable GUID
name	Variable name
value	Value
type	ascii, ucs2, u8, u16, u32, u64 or bytes
volatile	false adds EFI_VARIABLE_NON_VOLATILE

The variables are set before the entry starts.

[[entry.dt_patch]]

The entry accepts its own [[dt_patch]] array. Entry patches apply after global patches.

Kit.toml

schema = 1

[kit]
name = "MyKit"
version = "1.0.0"
description = "Board support"

[match]
arch = "AARCH64"
fdt_compatible = ["vendor,board"]
firmware_vendor = ["Vendor"]
requires_protocol = ["00000000-0000-0000-0000-000000000000"]

[[driver]]
file = "MyDriver.efi"
args = "from-kit"

[[overlay]]
file = "board.dtbo"

[[dt_patch]]
op = "set"
node = "/chosen"
prop = "from-kit"
value = "1"
type = "u32"

[[acpi]]
file = "DSDT.aml"

[[kext]]
bundle = "MyDriver.kext"
entry = "xnu"

Section	Meaning
[kit]	Name, version and description
[match]	All present keys must match
[[driver]]	Driver file relative to the kit
[[overlay]]	Device tree overlay relative to the kit
[[dt_patch]]	Device tree patch
[[acpi]]	ACPI table relative to the kit
[[kext]]	Kext bundle scoped to an entry id

Match keys:

Key	Meaning
arch	AARCH64
fdt_compatible	Strings in the firmware root compatible list
firmware_vendor	Substring of gST->FirmwareVendor
requires_protocol	GUIDs that must be installed

Within a key, any listed value matches. Across keys, every key must match.

Menu behavior

Condition	Result
Input device present	Countdown runs to the timeout
No input device	fallback_timeout applies
Negative timeout with input	Waits for a key
Negative timeout without input	fallback_timeout applies
Failed boot	Returns to the menu without a countdown

The menu shows the configuration source, the entry list, the injection summary and the first error.

Next steps

• Payload
• Kext bundles
• Device configuration