[PATCH v3 0/9] efi_loader: improve device-tree loading

[Simon Glass]

Hi Heinrich,

On Mon, 10 Jun 2024 at 08:00, Heinrich Schuchardt
<heinrich.schuchardt at canonical.com> wrote:
>
> On 10.06.24 15:53, Simon Glass wrote:
> > Hi Heinrich,
> >
> > On Mon, 10 Jun 2024 at 03:11, Heinrich Schuchardt
> > <heinrich.schuchardt at canonical.com> wrote:
> >>
> >> In U-Boot EFI boot options can already specify both an EFI binary and
> >> an initrd. With this series we can additionally define the matching
> >> device-tree to be loaded in the boot option.
> >>
> >> With the last patch the boot manager will fall back the device-tree
> >> specified by $fdtfile in directories '/dtb/', '/', or '/dtb/current/'
> >> on the boot device if no device-tree is specified in the boot
> >> option or via a bootefi command parameter.
> >>
> >> v3:
> >>          Add missing '@' in EFI_LP_DP_PART_FDT description.
> >>          Use calloc() instead of malloc() in load_fdt_from_load_option().
> >>          Add missing '@' in load_fdt_from_load_option function description
> >>          Rename struct efi_initrd_dp to efi_lo_dp_prefix.
> >>
> >> v2:
> >>          Update efi_dp_concat() instead of new function efi_dp_merge().
> >>          Carve out a function efi_load_option_dp_join() which we can
> >>          use both for the eficonfig and the efidebug command.
> >>          Rename variables id_dp, final_dp_size.
> >>          Rename create_initrd_dp() to create_lo_dp_part().
> >>          Use enum as parameter for create_lo_dp_part().
> >>          Put all related changes into one patch.
> >>
> >> Heinrich Schuchardt (8):
> >>    efi_loader: allow concatenation with contained end node
> >>    cmd: eficonfig: add support for setting fdt
> >>    cmd: efidebug: add support for setting fdt
> >>    efi_loader: load device-tree specified in boot option
> >>    efi_loader: move distro_efi_get_fdt_name()
> >>    efi_loader: return binary from efi_dp_from_lo()
> >>    efi_loader: export efi_load_image_from_path
> >>    efi_loader: load distro dtb in bootmgr
> >>
> >>   boot/bootmeth_efi.c                        |  60 +---------
> >>   cmd/eficonfig.c                            |  83 +++++++++----
> >>   cmd/efidebug.c                             | 130 +++++++++++++++------
> >>   include/efi_loader.h                       |  24 +++-
> >>   lib/efi_loader/Makefile                    |   1 +
> >>   lib/efi_loader/efi_bootbin.c               |   2 +-
> >>   lib/efi_loader/efi_bootmgr.c               |  75 +++++++++++-
> >>   lib/efi_loader/efi_boottime.c              |   3 +-
> >>   lib/efi_loader/efi_device_path.c           |  40 ++++---
> >>   lib/efi_loader/efi_device_path_utilities.c |   2 +-
> >>   lib/efi_loader/efi_fdt.c                   | 117 +++++++++++++++++++
> >>   lib/efi_loader/efi_helper.c                |  44 +++++++
> >>   12 files changed, 445 insertions(+), 136 deletions(-)
> >>   create mode 100644 lib/efi_loader/efi_fdt.c
> >>
> >
> > Somewhat related, what work has been done to support FIT, or to locate
> > a DT using the compatible string?
>
> CONFIG_BOOTM_EFI allows booting a FIT image containing an EFI binary and
> optionally a device-tree. You can manually select a configuration when
> invoking the bootm command. I am not aware of any automation for this
> selection.

Thanks for the info.

Can we perhaps require FIT_BEST_MATCH and then provide a way? All this
filename stuff is missing the point, really. It isn't going to get any
easier, either.

Regards,
Simon