150 lines
4.0 KiB
Groff
150 lines
4.0 KiB
Groff
.\" Copyright (c) 2014 The FreeBSD Foundation
|
|
.\" All rights reserved.
|
|
.\"
|
|
.\" Redistribution and use in source and binary forms, with or without
|
|
.\" modification, are permitted provided that the following conditions
|
|
.\" are met:
|
|
.\" 1. Redistributions of source code must retain the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, this list of conditions and the following disclaimer in the
|
|
.\" documentation and/or other materials provided with the distribution.
|
|
.\"
|
|
.\" THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
|
|
.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
|
|
.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
|
.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
|
.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
|
.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
|
.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
|
.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
.\" SUCH DAMAGE.
|
|
.\"
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd February 22, 2021
|
|
.Dt UEFI 8
|
|
.Os
|
|
.Sh NAME
|
|
.Nm UEFI
|
|
.Nd Unified Extensible Firmware Interface bootstrapping procedures
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Nm
|
|
Unified Extensible Firmware Interface provides boot- and run-time services
|
|
to operating systems.
|
|
.Nm
|
|
is a replacement for the legacy BIOS on the i386 and amd64 CPU architectures,
|
|
and is also used on arm, arm64 and ia64.
|
|
.Pp
|
|
The UEFI specification is the successor to the Extensible Firmware Interface
|
|
(EFI) specification.
|
|
The terms are often used interchangeably.
|
|
.Pp
|
|
The
|
|
.Nm
|
|
boot process loads system bootstrap code located in an EFI System Partition
|
|
(ESP).
|
|
The ESP is a GPT or MBR partition with a specific identifier that contains an
|
|
.Xr msdosfs 5
|
|
FAT file system with a specified file hierarchy.
|
|
.Bl -column -offset indent ".Sy Partition Scheme" ".Sy ESP Identifier"
|
|
.It Sy "Partition Scheme" Ta Sy "ESP Identifier"
|
|
.It GPT Ta C12A7328-F81F-11D2-BA4B-00A0C93EC93B
|
|
.It MBR Ta 0xEF
|
|
.El
|
|
.Pp
|
|
The
|
|
.Nm
|
|
boot process proceeds as follows:
|
|
.Bl -enum -offset indent -compact
|
|
.It
|
|
.Nm
|
|
firmware runs at power up and searches for an OS loader in the EFI system
|
|
partition.
|
|
The path to the loader may be set by an EFI environment variable.
|
|
If not set, an architecture-specific default is used.
|
|
.Bl -column -offset indent "Architecture" "Default Path"
|
|
.It Sy Architecture Ta Sy Default Path
|
|
.It amd64 Ta Pa /EFI/BOOT/BOOTX64.EFI
|
|
.It arm Ta Pa /EFI/BOOT/BOOTARM.EFI
|
|
.It arm64 Ta Pa /EFI/BOOT/BOOTAA64.EFI
|
|
.El
|
|
.Pp
|
|
The default
|
|
.Nm
|
|
boot configuration for
|
|
.Fx
|
|
installs
|
|
.Pa loader.efi
|
|
in the default path.
|
|
.It
|
|
.Pa loader.efi
|
|
reads boot configuration from
|
|
.Pa /boot.config
|
|
or
|
|
.Pa /boot/config .
|
|
.It
|
|
.Pa loader.efi
|
|
searches partitions of type
|
|
.Li freebsd-ufs
|
|
and
|
|
.Li freebsd-zfs
|
|
for
|
|
.Pa loader.efi .
|
|
The search begins with partitions on the device from which
|
|
.Pa loader.efi
|
|
was loaded, and continues with other available partitions.
|
|
If both
|
|
.Li freebsd-ufs
|
|
and
|
|
.Li freebsd-zfs
|
|
partitions exist on the same device the
|
|
.Li freebsd-zfs
|
|
partition is preferred.
|
|
.It
|
|
.Pa loader.efi
|
|
loads and boots the kernel, as described in
|
|
.Xr loader 8 .
|
|
.El
|
|
.Pp
|
|
The
|
|
.Xr vt 4
|
|
system console is automatically selected when booting via
|
|
.Nm .
|
|
.Sh FILES
|
|
.Bl -tag -width /boot/loader -compact
|
|
.Nm
|
|
bootstrap
|
|
.It Pa /boot/loader.efi
|
|
Final stage bootstrap
|
|
.It Pa /boot/kernel/kernel
|
|
default kernel
|
|
.It Pa /boot/kernel.old/kernel
|
|
typical non-default kernel (optional)
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr vt 4 ,
|
|
.Xr boot.config 5 ,
|
|
.Xr msdosfs 5 ,
|
|
.Xr boot 8 ,
|
|
.Xr efibootmgr 8 ,
|
|
.Xr efidp 8 ,
|
|
.Xr efivar 8 ,
|
|
.Xr gpart 8 ,
|
|
.Xr uefisign 8
|
|
.Sh HISTORY
|
|
EFI boot support for the ia64 architecture first appeared in
|
|
.Fx 5.0 .
|
|
.Nm
|
|
boot support for amd64 first appeared in
|
|
.Fx 10.1 ;
|
|
for arm64 in
|
|
.Fx 11.0 ;
|
|
for armv6 and armv7 in
|
|
.Fx 12.0 ;
|
|
and for riscv in
|
|
.Fx 13.0 .
|