Re: [PATCH RFC 9/9] doc: board: amlogic: add u-boot-spl documentation

On 07/09/2025 16:36, Ferass El Hafidi wrote:
> Add building and usage instructions for SPL.
> 
> Signed-off-by: Ferass El Hafidi <[email protected]>
> ---
>   doc/board/amlogic/index.rst             |  1 +
>   doc/board/amlogic/pre-generated-fip.rst |  9 ++++
>   doc/board/amlogic/spl.rst               | 77 +++++++++++++++++++++++++++++++++
>   3 files changed, 87 insertions(+)
> 
> diff --git a/doc/board/amlogic/index.rst b/doc/board/amlogic/index.rst
> index dcd935224ac0280a77455e3475a610fd81cfb80d..23380ac33f2b06efff7d4741ce2967d75671ca13 100644
> --- a/doc/board/amlogic/index.rst
> +++ b/doc/board/amlogic/index.rst
> @@ -78,6 +78,7 @@ Boot Documentation
>   
>      boot-flow
>      pre-generated-fip
> +   spl
>   
>   Board Documentation
>   -------------------
> diff --git a/doc/board/amlogic/pre-generated-fip.rst b/doc/board/amlogic/pre-generated-fip.rst
> index 6a43d776d43f35cbffc7ba9e72bf05dd719f6387..d820bd09115952d4fca2b9e7d7b5a9e30bd11430 100644
> --- a/doc/board/amlogic/pre-generated-fip.rst
> +++ b/doc/board/amlogic/pre-generated-fip.rst
> @@ -98,6 +98,13 @@ The repo also provides the following files used with GXBB boards:
>   The repo also supports the open-source 'gxlimg' signing tool that can be used to sign
>   U-Boot binaries for GXL/GXM/G12A/G12B/SM1 boards: https://github.com/repk/gxlimg
>   
> +The following binaries can be replaced with open-source implementations:
> +
> +- bl2.bin (GXBB and GXL only)
> +- bl31.img (GXBB, GXL, AXG and G12A only)
> +
> +Refer to `Experimental U-Boot SPL Support`_ if you wish to replace them.
> +
>   Licensing
>   ---------
>   
> @@ -129,3 +136,5 @@ clarified. The current Amlogic distribution licence is below:
>       // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
>       // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
>       // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> +
> +.. _`Experimental U-Boot SPL Support`: spl.rst
> diff --git a/doc/board/amlogic/spl.rst b/doc/board/amlogic/spl.rst
> new file mode 100644
> index 0000000000000000000000000000000000000000..39d50e3da87d71f62cec1903c441c334bf7020e8
> --- /dev/null
> +++ b/doc/board/amlogic/spl.rst
> @@ -0,0 +1,77 @@
> +.. SPDX-License-Identifier: GPL-2.0+
> +
> +Experimental U-Boot SPL Support
> +===============================
> +
> +There's some experimental support for some Amlogic SoCs, in U-Boot SPL.  It
> +replaces the proprietary bl2.bin blob used for DRAM init.  Currently Meson GX
> +SoCs (GXBB, GXL) are supported.
> +
> +A subset of Amlogic boards have SPL enabled.  These boards have been tested and
> +known to work to an extent.
> +
> +
> +Building Arm Trusted Firmware (TF-A)
> +------------------------------------
> +
> +This U-Boot SPL port requires the BL31 stage of mainline Arm Trusted
> +Firmware-A firmware. It provides an open source implementation of secure
> +software for Armv8-A. Build it with:
> +
> +.. code-block:: bash
> +
> +    $ git clone https://git.trustedfirmware.org/TF-A/trusted-firmware-a.git
> +    $ cd trusted-firmware-a
> +    $ make CROSS_COMPILE=aarch64-linux-gnu- PLAT=your_soc DEBUG=1
> +
> +Replace ``your_soc`` with the SoC target you wish to build for. For GXBB it's
> +``gxbb`` and for GXL it's ``gxl``.
> +
> +
> +Building a bl30_new.bin binary
> +------------------------------
> +
> +``bl30_new.bin`` has both ``bl30.bin`` and ``bl301.bin`` binary blobs
> +bundled. The former is the proper system control processor firmware and the
> +latter is a "plug-in" for board-specific DVFS/suspend-resume parameters. For
> +more info you may wish to read this page: `Pre-Generated FIP File Repo`_.
> +
> +To build using the FIP file repo, simply issue the following commands:
> +
> +.. code-block:: bash
> +
> +    $ cd amlogic-boot-fip/your_board
> +    $ make bl30_new.bin
> +
> +
> +.. _`Pre-Generated FIP File Repo`: pre-generated-fip.rst
> +
> +
> +U-Boot compilation
> +------------------
> +
> +U-Boot SPL is not enabled by default, instead there are config fragments that
> +can be used to enable it, with per-board configuration:
> +
> +- ``spl-libretech-cc-1gb.config``: 1 GB LePotato board
> +- ``spl-libretech-cc-2gb.config``: 2 GB LePotato board
> +- ``spl-odroid-c2.config``: ODROID-C2
> +- ``spl-videostrong-kii-pro.config``: Videostrong KII Pro
> +
> +Pick one of them then:
> +
> +.. code-block:: bash
> +
> +    $ export CROSS_COMPILE=aarch64-linux-gnu-
> +    $ export BL31=path/to/tf-a/bl31.bin                 # Upstream TF-A BL31 binary
> +    $ export SCP=path/to/bl30_new.bin                   # bl30_new.bin binary
> +    $ make <yourboardname>_defconfig spl-<yourboardname>.config
> +    $ make
> +
> +Write to SD:
> +
> +.. code-block:: bash
> +
> +    $ DEV=/dev/boot_device
> +    $ dd if=u-boot-meson-with-spl.bin of=$DEV conv=fsync,notrunc bs=512 seek=1
> +
> 

It's very nice :-)

Reviewed-by: Neil Armstrong <[email protected]>