On 15.12.23 13:11, Stefan Kerkmann wrote:
> This documents an alternate method for chainloading Barebox from U-Boot
> by packing the Barebox image and matching device tree into an FIT image.
S-o-b missing.
With that fixed:
Acked-by: Ahmad Fatoum <a.fatoum@xxxxxxxxxxxxxx>
> ---
> Documentation/user/barebox.rst | 26 ++++++++++++++++++++++++++
> 1 file changed, 26 insertions(+)
>
> diff --git a/Documentation/user/barebox.rst b/Documentation/user/barebox.rst
> index f4e600bde0..ea4db28d08 100644
> --- a/Documentation/user/barebox.rst
> +++ b/Documentation/user/barebox.rst
> @@ -215,6 +215,32 @@ like a Linux kernel that is passed an external device tree. For example:
> U-Boot: bootz $kernel_addr - $fdt_addr # On 32-bit ARM
> U-Boot: booti $kernel_addr - $fdt_addr # for other platforms
>
> +Another option is to generate a FIT image containing the generic DT image and a
> +matching device tree with ``mkimage``:
> +
> +.. code-block:: console
> + sh: mkimage --architecture arm \
> + --os linux \
> + --type kernel \
> + --fit auto \
> + --load-address $kernel_addr_r \
> + --compression none \
> + --image images/barebox-dt-2nd.img \
> + --device-tree arch/${ARCH}/dts/my-board.dtb \
> + barebox-dt-2nd.fit
> +
> +This FIT image can then be loaded by U-Boot and executed just like a regular
> +Linux kernel:
> +
> +.. code-block:: console
> + U-Boot: tftp $fit_addr barebox-dt-2nd.fit
> + U-Boot: bootm $fit_addr
> +
> +Make sure that the address in ``$fit_addr`` is different from the
> +``$kernel_addr_r`` passed to ``mkimage`` as the load address of the Kernel
> +image. Otherwise U-Boot may attempt to overwrite the FIT image with the barebox
> +image contained within.
> +
> For non-DT enabled-bootloaders or other architectures, often the normal barebox
> binaries can also be used as they are designed to be startable second stage
> from another bootloader, where possible. For example, if you have U-Boot running
>
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