[PATCH v2 0/4] Add support for booting EFI FIT images

[Cristian Ciocaltea <cristian.ciocaltea@gmail.com>]

Currently the only way to run an EFI binary like GRUB2 is via the
'bootefi' command, which cannot be used in a verified boot scenario.

The obvious solution to this limitation is to add support for
booting FIT images containing those EFI binaries.

The implementation relies on a new image type - IH_OS_EFI - which
can be created by using 'os = "efi"' inside an ITS file:

/ {
    #address-cells = <1>;

    images {
        efi-grub {
            description = "GRUB EFI";
            data = /incbin/("EFI/BOOT/bootarm.efi");
            type = "kernel_noload";
            arch = "arm";
            os = "efi";
            compression = "none";
            load = <0x0>;
            entry = <0x0>;
            hash-1 {
                algo = "sha256";
            };
        };
    };

    configurations {
        default = "config-grub";
        config-grub {
            kernel = "efi-grub";
            signature-1 {
                algo = "sha256,rsa2048";
                sign-images = "kernel";
            };
        };
    };
};

The bootm command has been extended to handle the IH_OS_EFI images.
To enable this feature, a new configuration option has been added:
BOOTM_EFI

I tested the solution using the 'qemu_arm' board:

=> load scsi 0:1 ${kernel_addr_r} efi-image.fit
=> bootm ${kernel_addr_r}#config-grub

Changes since v1:
 * Rebase patches on Heinrich Schuchardt's patch series:
   efi_loader: prepare for FIT images
   https://lists.denx.de/pipermail/u-boot/2019-December/393192.html
 * Add sample configuration: doc/uImage.FIT/uefi.its
 * Update uefi documentation: doc/uefi/uefi.rst

Cristian Ciocaltea (4):
  image: Add IH_OS_EFI for EFI chain-load boot
  bootm: Add a bootm command for type IH_OS_EFI
  doc: Add sample uefi.its image description file
  doc: uefi.rst: Document launching UEFI binaries from FIT images

 cmd/Kconfig             |  7 +++++
 common/bootm_os.c       | 61 +++++++++++++++++++++++++++++++++++++
 common/image-fit.c      |  3 +-
 common/image.c          |  1 +
 doc/uImage.FIT/uefi.its | 67 +++++++++++++++++++++++++++++++++++++++++
 doc/uefi/uefi.rst       | 34 +++++++++++++++++++++
 include/image.h         |  1 +
 7 files changed, 173 insertions(+), 1 deletion(-)
 create mode 100644 doc/uImage.FIT/uefi.its

-- 
2.17.1