[U-Boot] [PATCH 3/3] doc: SPL: Add README for secure boot support

[Simon Glass]

Hi,

On 14 July 2016 at 10:27, Sumit Garg <sumit.garg at nxp.com> wrote:
> Adds information regarding SPL handling validation process of main u-boot
> image on power/mpc85xx and arm/layerscape platforms.
>
> Signed-off-by: Sumit Garg <sumit.garg at nxp.com>
> ---
>
> Changes PATCH v5->PATCH v6:
> Added README for SECURE BOOT support in SPL framework.
>
>  doc/SPL/README.spl-secure-boot | 18 ++++++++++++++++++
>  1 file changed, 18 insertions(+)
>  create mode 100644 doc/SPL/README.spl-secure-boot

Reviewed-by: Simon Glass <sjg at chromium.org>

>
> diff --git a/doc/SPL/README.spl-secure-boot b/doc/SPL/README.spl-secure-boot
> new file mode 100644
> index 0000000..f2f8d78
> --- /dev/null
> +++ b/doc/SPL/README.spl-secure-boot
> @@ -0,0 +1,18 @@
> +Overview of SPL verified boot on powerpc/mpc85xx & arm/layerscape platforms
> +===========================================================================
> +
> +Introduction
> +------------
> +
> +This document provides an overview of how SPL verified boot works on powerpc/
> +mpc85xx & arm/layerscape platforms.
> +
> +Methodology
> +-----------
> +
> +The SPL image is responsible for loading the next stage boot loader, which is
> +the main u-boot image. For secure boot process on these platforms ROM verifies
> +SPL image, so to continue chain of trust SPL image verifies U-boot image using
> +spl_validate_uboot(). This function uses QorIQ Trust Architecture header
> +(appended to U-boot image) to validate the U-boot binary just before passing
> +control to it.

Please use "U-Boot"

This seems a bit brief. Are there instructions on how to actually set it up?

Regards,
Simon