[PATCH 0/3] Add initrd support to bootm EFI payloads

[Ilias Apalodimas]

On Wed, 19 Mar 2025 at 14:12, Adriano Córdova <adrianox at gmail.com> wrote:
>
>
>
> El mié, 19 mar 2025 a las 5:48, Ilias Apalodimas (<ilias.apalodimas at linaro.org>) escribió:
>>
>> Hi Adriano,
>>
>> On Tue, 18 Mar 2025 at 15:23, Adriano Cordova <adrianox at gmail.com> wrote:
>> >
>> > Next boot stages can acces an initrd via a handle with a specific device
>> > path and an EFI_LOAD_FILE2_PROTOCOL installed on it. In U-Boot, this functionality
>> > is currently only implemented when booting with the EFI boot manager. This series
>> > implements this functionality also for the bootm command when the os is of EFI type,
>> > e.g. when booting FIT images with an EFI kernel.
>>
>> I'll have a look at the patches shortly. I have a question about the
>> entire series though.
>>
>> The initrd was plugged into the efi boot manager because it's easy to
>> configure entries of
>> kernel-initrd-dtb. The initrd can also be loaded by passing a kernel
>> command line parameter.
>>
>> That parameter can either be initrd=<file> with the limitation that
>> the initrd needs to be on the same filesystem as the kernel image.
>> On newer kernels you can also pass initrd=<device path>. I am not sure
>> what's the best option when loading the initrd for a FIT image.
>>
>> Thanks
>> /Ilias
>
>
> Currently the initrd in FIT images with EFI os is completely ignored. It can't be passed as initrd=<file>
> because it is not a file, it is just memory mapped, and I am not sure if it can be passed as initrd=<device path>
> as I am not sure if the kernel expects a file system device path or if a memory device path would be picked
> up.
> In this series the functionality is added following what bootmgr already does, which also works for passing
> the initrd to a boot stage that understands EFI but not command line, but investigating the other way is also an option.

Yea, I don't know if loading it from a memory-backed device path is an
option either. I am fine with the current idea, I was just wondering
if we specifically want EFI LOAD2 or just find a way to load it.

Thanks
/Ilias
>
> Thanks,
> Adriano
>>
>>
>>
>> >
>> > Adriano Cordova (3):
>> >   efi_loader: efi_load_initrd: provide a memory mapped initrd
>> >   efi_loader: binary_run: register an initrd
>> >   bootm: add support for initrd in do_bootm_efi
>> >
>> >  boot/bootm_os.c                  |  4 +-
>> >  cmd/bootefi.c                    |  2 +-
>> >  include/efi_loader.h             |  4 +-
>> >  lib/efi_loader/efi_bootbin.c     | 20 +++++++--
>> >  lib/efi_loader/efi_bootmgr.c     |  2 +-
>> >  lib/efi_loader/efi_load_initrd.c | 71 +++++++++++++++++++++++++++-----
>> >  6 files changed, 84 insertions(+), 19 deletions(-)
>> >
>> > --
>> > 2.48.1
>> >