brain-hackers_pepepper-mirror/u-boot-brain
1
0
Fork 0
mirror of https://github.com/brain-hackers/u-boot-brain synced 2024-06-09 23:36:03 +09:00
Code Issues Projects Releases Wiki Activity

doc: Update uefi documentation for initrd loading options

Browse Source 
Document the command line options for efidebug and initrd loading

Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
Rewiewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
This commit is contained in:
Ilias Apalodimas 2021-03-17 21:55:02 +02:00 committed by Heinrich Schuchardt
parent a1e95e3805
commit cd64031c16
1 changed files with 21 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
doc/develop/uefi/uefi.rst
View File

@ -180,6 +180,12 @@ Set up boot parameters on your board::
efidebug boot add -b 1 HELLO mmc 0:1 /helloworld.efi.signed "" efidebug boot add -b 1 HELLO mmc 0:1 /helloworld.efi.signed ""
Since kernel 5.7 there's an alternative way of loading an initrd using
LoadFile2 protocol if CONFIG_EFI_LOAD_FILE2_INITRD is enabled.
The initrd path can be specified with::
efidebug boot add -b ABE0 'kernel' mmc 0:1 Image -i mmc 0:1 initrd
Now your board can run the signed image via the boot manager (see below). Now your board can run the signed image via the boot manager (see below).
You can also try this sequence by running Pytest, test_efi_secboot, You can also try this sequence by running Pytest, test_efi_secboot,
on the sandbox on the sandbox
@ -484,7 +490,21 @@ The load file 2 protocol can be used by the Linux kernel to load the initial
RAM disk. U-Boot can be configured to provide an implementation with:: RAM disk. U-Boot can be configured to provide an implementation with::
EFI_LOAD_FILE2_INITRD=y EFI_LOAD_FILE2_INITRD=y
EFI_INITRD_FILESPEC=interface dev:part path_to_initrd
When the option is enabled the user can add the initrd path with the efidebug
command.
Load options Boot#### have a FilePathList[] member. The first element of
the array (FilePathList[0]) is the EFI binary to execute. When an initrd
is specified the Device Path for the initrd is denoted by a VenMedia node
with the EFI_INITRD_MEDIA_GUID. Each entry of the array is terminated by the
'end of entire device path' subtype (0xff). If a user wants to define multiple
initrds, those must by separated by the 'end of this instance' identifier of
the end node (0x01).
So our final format of the FilePathList[] is::
Loaded image - end node (0xff) - VenMedia - initrd_1 - [end node (0x01) - initrd_n ...] - end node (0xff)
Links Links
----- -----