tools: mkimage: Add Allwinner TOC0 support

Most Allwinner sunxi SoCs have separate boot ROMs in non-secure and
secure mode. The "non-secure" or "normal" boot ROM (NBROM) uses the
existing sunxi_egon image type. The secure boot ROM (SBROM) uses a
completely different image type, known as TOC0.

A TOC0 image is composed of a header and two or more items. One item
is the firmware binary. The others form a chain linking the firmware
signature to the root-of-trust public key (ROTPK), which has its hash
burned in the SoC's eFuses. Signatures are made using RSA-2048 + SHA256.

The pseudo-ASN.1 structure is manually assembled; this is done to work
around bugs/quirks in the boot ROM, which vary between SoCs. This TOC0
implementation has been verified to work with the A50, A64, H5, H6,
and H616 SBROMs, and it may work with other SoCs.

Signed-off-by: Samuel Holland <samuel@sholland.org>
Acked-by: Andre Przywara <andre.przywara@arm.com>
Signed-off-by: Andre Przywara <andre.przywara@arm.com>

tools: mkimage: Add Allwinner eGON support

So far we used the separate mksunxiboot tool for generating a bootable
image for Allwinner SPLs, probably just for historical reasons.

Use the mkimage framework to generate a so called eGON image the
Allwinner BROM expects.
The new image type is called "sunxi_egon", to differentiate it
from the (still to be implemented) secure boot TOC0 image.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@siol.net>
Reviewed-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Simon Glass <sjg@chromium.org>

sunxi: Factor out eGON BROM header description

To be able to easily share the Allwinner eGON BROM header structure
between the tools and the SPL code, move the struct definition into a
separate header file.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@siol.net>
Reviewed-by: Samuel Holland <samuel@sholland.org>

tools: mkimage: Add Allwinner eGON support

So far we used the separate mksunxiboot tool for generating a bootable
image for Allwinner SPLs, probably just for historical reasons.

Use the mkimage framework to generate a so called eGON image the
Allwinner BROM expects.
The new image type is called "sunxi_egon", to differentiate it
from the (still to be implemented) secure boot TOC0 image.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@siol.net>
Reviewed-by: Samuel Holland <samuel@sholland.org>
Reviewed-by: Simon Glass <sjg@chromium.org>

sunxi: Factor out eGON BROM header description

To be able to easily share the Allwinner eGON BROM header structure
between the tools and the SPL code, move the struct definition into a
separate header file.

Signed-off-by: Andre Przywara <andre.przywara@arm.com>
Reviewed-by: Jernej Skrabec <jernej.skrabec@siol.net>
Reviewed-by: Samuel Holland <samuel@sholland.org>