Re: [PATCH] wic: bootimg-efi-isar: Add support for loading device tree files

[Jan Kiszka <jan.kiszka@siemens.com>]

On 11.07.22 15:12, Henning Schild wrote:
> Am Sun, 10 Jul 2022 22:51:44 +0200
> schrieb Jan Kiszka <jan.kiszka@siemens.com>:
> 
>> From: Jan Kiszka <jan.kiszka@siemens.com>
>>
>> For device tree using systems, add support to set a custom devices
>> tree during UEFI boot. This requires to copy the DTB file to the boot
>> partition and to add the respective loader entries to the
>> configuration files.
>>
>> Both grub and systemd-boot support only loading a specific device
>> tree. Therefore refuse to work if DTB_FILES contains more than one
>> entry.
>>
>> This has been tested with grub from bullseye and systemd from
>> bullseye-backport. The latter is needed as only systemd 250 gained the
>> required feature.
>>
>> Out of scope are overlays (only supported by systemd-boot) as well as
>> unified kernel images (practically broken on non-x86 with current
>> toolchains).
>>
>> Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
>> ---
>>  meta/classes/imagetypes_wic.bbclass           |  2 +-
>>  .../wic/plugins/source/bootimg-efi-isar.py    | 39
>> +++++++++++++------ 2 files changed, 29 insertions(+), 12 deletions(-)
>>
>> diff --git a/meta/classes/imagetypes_wic.bbclass
>> b/meta/classes/imagetypes_wic.bbclass index 61a74d4a..3a577f71 100644
>> --- a/meta/classes/imagetypes_wic.bbclass
>> +++ b/meta/classes/imagetypes_wic.bbclass
>> @@ -106,7 +106,7 @@ WICVARS += "\
>>             ROOTFS_SIZE STAGING_DATADIR STAGING_DIR STAGING_LIBDIR
>> TARGET_SYS TRANSLATED_TARGET_ARCH" 
>>  # Isar specific vars used in our plugins
>> -WICVARS += "DISTRO DISTRO_ARCH"
>> +WICVARS += "DISTRO DISTRO_ARCH DTB_FILES"
>>  
>>  python do_rootfs_wicenv () {
>>      wicvars = d.getVar('WICVARS', True)
>> diff --git a/meta/scripts/lib/wic/plugins/source/bootimg-efi-isar.py
>> b/meta/scripts/lib/wic/plugins/source/bootimg-efi-isar.py index
>> a24e04f3..aff51e81 100644 ---
>> a/meta/scripts/lib/wic/plugins/source/bootimg-efi-isar.py +++
>> b/meta/scripts/lib/wic/plugins/source/bootimg-efi-isar.py 
> 
> This file is a fork from OE with very minimal non-functional changes to
> make it into Isar. I am afraid that feature will have to make it via OE.
> 

Right, from

 bootimg-efi-isar.py |   65 +++++++++++++++++++++++++++++++++++++++++++++++-----
 1 file changed, 59 insertions(+), 6 deletions(-)

to

 bootimg-efi-isar.py |  104 +++++++++++++++++++++++++++++++++++++++++++---------
 1 file changed, 87 insertions(+), 17 deletions(-)

The problem is that OE core has no DTB_FILES, and seems like not even a 
concept of injecting DTBs via the bootloader, thus passing them to wic.

Jan

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