[RESEND PATCH v1 0/5] Add support for embedding public key in platform's dtb

[Sughosh Ganu <sughosh.ganu@linaro.org>]

Resending the same set of patches. For some reason, the first
paragraph of the cover letter got deleted in the original
set. Hopefully this will go through fine.

These patches add support for embedding the public key efi signature
list(esl) file into the platform's device tree. The current solution
for the Qemu arm64 platform has the public key as part of an overlay,
and stored on the Efi System Partition(ESP). Having the provision to
embed the public key into the platform's dtb which is then
concatenated with the u-boot binary is a better approach, recommended
by Heinrich[1].

Patch 1 fixes an issue of selection of IMAGE_SIGN_INFO config option
when capsule authentication is enabled.

Patch 2 add two config symbols, EFI_PKEY_DTB_EMBED and EFI_PKEY_FILE
which are used for enabling embedding of the public key in the dtb,
and specifying the esl file name.

Patch 3 moves efi_capsule_auth_enabled as a weak function, which can
be used as a default mechanism for checking if capsule authentication
has been enabled.

Patch 4 adds a default weak function for retrieving the public key
from the platform's dtb.

Patch 5 adds the functionality to embed the esl file into the
platform's dtb during the platform build.

I have tested this functionality on the STM32MP157C DK2 board, and it
works as expected.

[1] - https://lists.denx.de/pipermail/u-boot/2021-March/442867.html 

Sughosh Ganu (5):
  efi_loader: Kconfig: Select IMAGE_SIGN_INFO when capsule
    authentication is enabled
  efi_loader: Kconfig: Add symbols for embedding the public key into the
    platform's dtb
  efi_capsule: Add a weak function to check whether capsule
    authentication is enabled
  efi_capsule: Add a weak function to get the public key needed for
    capsule authentication
  Makefile: Add provision for embedding public key in platform's dtb

 Makefile                              | 10 ++++++
 board/emulation/common/qemu_capsule.c |  6 ----
 lib/efi_loader/Kconfig                | 16 ++++++++++
 lib/efi_loader/efi_capsule.c          | 44 ++++++++++++++++++++++++---
 4 files changed, 66 insertions(+), 10 deletions(-)

-- 
2.17.1