Difference between revisions of "UEFI"

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(Created page with "{{welcome}} ==Introduction== UEFI -- Unified Extensible Firmware Interface bootstrapping procedures ==DESCRIPTION== The UEFI Unified Extensible Firmware Interface provides...")
 
 
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{{welcome}}
 
{{welcome}}
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{{Navbar GhostBSD Boot Process}}
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==Introduction==
 
==Introduction==
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UEFI -- Unified Extensible Firmware Interface bootstrapping procedures
 
UEFI -- Unified Extensible Firmware Interface bootstrapping procedures
  
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==DESCRIPTION==
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==Description==
  
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The UEFI Unified Extensible Firmware Interface provides boot- and runtime services to operating systems.  UEFI is a replacement for the legacy  BIOS on the i386 and amd64 CPU architectures, and is also used on arm,    arm64 and ia64.
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The [https://www.freebsd.org/cgi/man.cgi?query=uefi&sektion=8&apropos=0&manpath=FreeBSD+12.1-RELEASE+and+Ports UEFI] Unified Extensible Firmware Interface provides boot- and runtime services to operating systems.  UEFI is a replacement for the legacy  BIOS on the i386 and amd64 CPU architectures, and is also used on arm,    arm64 and ia64.
  
 
The UEFI specification is the successor to the Extensible Firmware Interface (EFI) specification. The terms are often used interchangeably.
 
The UEFI specification is the successor to the Extensible Firmware Interface (EFI) specification. The terms are often used interchangeably.
  
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The UEFI 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 msdosfs(5) FAT file system with a specified  file hierarchy.
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The UEFI 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 [https://www.freebsd.org/cgi/man.cgi?query=msdosfs&sektion=5&apropos=0&manpath=FreeBSD+12.1-RELEASE+and+Ports msdosfs(5)] FAT file system with a specified  file hierarchy.
  
 
{|class="wikitable" style="width:96.5%;background:#FFFFFF; border:2px solid #008000;text-align:left;padding: 10px"  
 
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The UEFI boot process proceeds as follows
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The UEFI boot process proceeds as follows<br/>
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1. UEFI firmware runs at power up and searches for an OS loader in the EFI system partition.  The path to the loader may beset by an EFI environment variable.  If not set, an architecture-specific default is used.
 
1. UEFI firmware runs at power up and searches for an OS loader in the EFI system partition.  The path to the loader may beset by an EFI environment variable.  If not set, an architecture-specific default is used.
  
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The default UEFI boot configuration for FreeBSD installs boot1.efi in the default path.
 
The default UEFI boot configuration for FreeBSD installs boot1.efi in the default path.
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2.  boot1.efi reads boot configuration from /boot.config or /boot/config.  Unlike other first-stage boot loaders,
 
2.  boot1.efi reads boot configuration from /boot.config or /boot/config.  Unlike other first-stage boot loaders,
 
boot1.efi passes the configuration to the next stage boot loader and does not itself act on the contents of the file.
 
boot1.efi passes the configuration to the next stage boot loader and does not itself act on the contents of the file.
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3.  boot1.efi searches partitions of type freebsd-ufs and freebsd-zfs for loader.efi.  The search begins with partitions
 
3.  boot1.efi searches partitions of type freebsd-ufs and freebsd-zfs for loader.efi.  The search begins with partitions
 
on the device from which boot1.efi was loaded, and continues with other available partitions.  If both freebsd-ufs and
 
on the device from which boot1.efi was loaded, and continues with other available partitions.  If both freebsd-ufs and
 
freebsd-zfs partitions exist on the same device the freebsd-zfs partition is preferred.  boot1.efi then loads and
 
freebsd-zfs partitions exist on the same device the freebsd-zfs partition is preferred.  boot1.efi then loads and
 
executes loader.efi.
 
executes loader.efi.
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4. loader.efi loads and boots the kernel, as described in loader(8).
 
  
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The vt(4) system console is automatically selected when booting via UEFI.
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4. loader.efi loads and boots the kernel, as described in [https://www.freebsd.org/cgi/man.cgi?query=loader&sektion=8&apropos=0&manpath=FreeBSD+12.1-RELEASE+and+Ports loader(8)].
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The [https://www.freebsd.org/cgi/man.cgi?query=vt&sektion=4&apropos=0&manpath=FreeBSD+12.1-RELEASE+and+Ports vt(4)] system console is automatically selected when booting via UEFI.
  
 
FILES
 
FILES
 
{|class="wikitable" style="width:96.5%;background:#FFFFFF; border:2px solid #008000;text-align:left;padding: 10px"  
 
{|class="wikitable" style="width:96.5%;background:#FFFFFF; border:2px solid #008000;text-align:left;padding: 10px"  
 
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|-
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! scope="col" style="width: 100px;"|'''Architecture'''
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! scope="col" style="width: 100px;"|'''File'''
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! scope="col" style="width: 350px;"|'''Default Path'''
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! scope="col" style="width: 350px;"|'''Description'''
 
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|/boot/boot1.efi|| First stage UEFI bootstrap
 
|/boot/boot1.efi|| First stage UEFI bootstrap
 
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|-
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|/boot/boot1.efifat||msdosfs(5) FAT file system image containing boot1.efi for  use by bsdinstall(8) and the bootcode argument to gpart(8).
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|/boot/boot1.efifat||[https://www.freebsd.org/cgi/man.cgi?query=msdosfs&sektion=5&apropos=0&manpath=FreeBSD+12.1-RELEASE+and+Ports msdosfs(5)] FAT file system image containing boot1.efi for  use by [https://www.freebsd.org/cgi/man.cgi?query=bsdinstall&sektion=8&apropos=0&manpath=FreeBSD+12.1-RELEASE+and+Ports bsdinstall(8)] and the bootcode argument to [https://www.freebsd.org/cgi/man.cgi?query=gpart&sektion=8&apropos=0&manpath=FreeBSD+12.1-RELEASE+and+Ports gpart(8)].
 
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|/boot/loader.efi||Final stage bootstrap
 
|/boot/loader.efi||Final stage bootstrap
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The next steps are described as [[GhostBSD Boot Process#Bootstrap Process|Bootstrap Process]].
  
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==Additional information about UEFI==
  
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[https://wiki.freebsd.org/UEFI?highlight=%28%5CbCategoryProject%5Cb%29 FreeBSD about UEFI]
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Latest revision as of 06:52, 5 October 2020

Welcome to Icon Disti GhostBSD.png UEFI.
GhostBSD Boot Process
MBR and GPT UEFI OpenRC /boot/
Back to the Icon Disti GhostBSD.pngSystem


Introduction[edit]

UEFI -- Unified Extensible Firmware Interface bootstrapping procedures

Description[edit]

The UEFI Unified Extensible Firmware Interface provides boot- and runtime services to operating systems. UEFI is a replacement for the legacy BIOS on the i386 and amd64 CPU architectures, and is also used on arm, arm64 and ia64.

The UEFI specification is the successor to the Extensible Firmware Interface (EFI) specification. The terms are often used interchangeably.

The UEFI 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 msdosfs(5) FAT file system with a specified file hierarchy.

Partition Scheme ESP Identifier
GPT C12A7328-F81F-11D2-BA4B-00A0C93EC93B
MBR 0xEF

The UEFI boot process proceeds as follows

1. UEFI firmware runs at power up and searches for an OS loader in the EFI system partition. The path to the loader may beset by an EFI environment variable. If not set, an architecture-specific default is used.

Architecture Default Path
amd64 /EFI/BOOT/BOOTX64.EFI
arm64 /EFI/BOOT/BOOTAA64.EFI

The default UEFI boot configuration for FreeBSD installs boot1.efi in the default path.

2. boot1.efi reads boot configuration from /boot.config or /boot/config. Unlike other first-stage boot loaders, boot1.efi passes the configuration to the next stage boot loader and does not itself act on the contents of the file.

3. boot1.efi searches partitions of type freebsd-ufs and freebsd-zfs for loader.efi. The search begins with partitions on the device from which boot1.efi was loaded, and continues with other available partitions. If both freebsd-ufs and freebsd-zfs partitions exist on the same device the freebsd-zfs partition is preferred. boot1.efi then loads and executes loader.efi.

4. loader.efi loads and boots the kernel, as described in loader(8).

The vt(4) system console is automatically selected when booting via UEFI.

FILES

File Description
/boot/boot1.efi First stage UEFI bootstrap
/boot/boot1.efifat msdosfs(5) FAT file system image containing boot1.efi for use by bsdinstall(8) and the bootcode argument to gpart(8).
/boot/loader.efi Final stage bootstrap
/boot/kernel/kernel default kernel
/boot/kernel.old/kernel typical non-default kernel (optional)


The next steps are described as Bootstrap Process.

Additional information about UEFI[edit]

FreeBSD about UEFI

Retrieved from "http://wiki.ghostbsd.org/index.php?title=UEFI&oldid=6885"