NAME
efi — Extensible Firmware Interface description
DESCRIPTION
The
EFI
(Extensible Firmware Interface)
is an interface between
HP-UX
and the Itanium-based platform firmware. The
file system supported by the Extensible Firmware Interface is based
on the FAT file system.
EFI
encompasses the use of FAT-32 for a system
partition, and FAT-12 or FAT-16 for removable media. The system
partition is required on a bootable disk for the Itanium-based platform.
For a hard disk, the system partition is a contiguous grouping of sectors
on the disk, where the starting sector and size are defined by the
EFI
partition table, which resides on the second logical block of the
hard disk, and/or by the Master Boot Record (MBR), which resides on
the first sector of the hard disk. For a floppy disk, a partition is
defined to be the entire disk.
The System Partition can contain directories, data files, and
EFI
Images.
The
EFI
system firmware may search the
\EFI
directory of the
EFI
system partition,
EFI
volume, to find possible
EFI
Images that
can be loaded. The
HP-UX
bootloader is one example of an
EFI
Image.
HP-UX
contains a set of
EFI
utilities:
The
EFI
utilities are the only utilities in
HP-UX
where the internal structure of an
EFI
volume is known.
To the rest of
HP-UX,
an
EFI
system partition is simply a partition containing unspecified data.
The
EFI
volume cannot be mounted to
HP-UX
currently.
An
EFI
volume can be created on any
HP-UX
file (either regular disk file or device special file)
that supports random access via
lseek(2).
Within an
EFI
volume, individual files and directories are identified by
1- to 255-character file names.
File names can consist of any alphanumeric characters
(A through Z, a through z, and 0 through 9)
and the certain set of special characters (. $ % ' - _ @ ~ `
! ( ) + , : ; = # & ? ^ [ ] { } space).
The first character of an
EFI
file name can be any valid
EFI
characters, except the space.
When comparing two
EFI
names, differences in the case of alphabetic
characters are not significant. For example,
the following file names are considered the same:
If one exists, the user
will not be able to create the other.
The directory may be made up of multiple components,
separated by slashes(/). The last directory component must be
followed by a slash to separate it from the file name. There
are two special directory components, (.) and (..). They
represent the current directory and the parent directory as in other
file systems.