[PATCH v4 3/3] doc: sophgo: milkv_duo: document Milk-V Duo board

[Heinrich Schuchardt]

On 1/28/24 08:05, Kongyang Liu wrote:
> Add document for Milk-V Duo board which based on Sophgo's CV1800B SoC.
>
> Signed-off-by: Kongyang Liu <seashell11234455 at gmail.com>
>
> ---
>
> (no changes since v3)
>
> Changes in v3:
> - Add brief description of the procedure to run u-boot-dtb.bin
>
>   doc/board/index.rst            |  1 +
>   doc/board/sophgo/index.rst     |  8 +++++
>   doc/board/sophgo/milkv_duo.rst | 64 ++++++++++++++++++++++++++++++++++
>   3 files changed, 73 insertions(+)
>   create mode 100644 doc/board/sophgo/index.rst
>   create mode 100644 doc/board/sophgo/milkv_duo.rst
>
> diff --git a/doc/board/index.rst b/doc/board/index.rst
> index c96e5fda28..d0f9f355d2 100644
> --- a/doc/board/index.rst
> +++ b/doc/board/index.rst
> @@ -46,6 +46,7 @@ Board-specific doc
>      sifive/index
>      sipeed/index
>      socionext/index
> +   sophgo/index
>      st/index
>      starfive/index
>      ste/index
> diff --git a/doc/board/sophgo/index.rst b/doc/board/sophgo/index.rst
> new file mode 100644
> index 0000000000..e097afdac6
> --- /dev/null
> +++ b/doc/board/sophgo/index.rst
> @@ -0,0 +1,8 @@
> +.. SPDX-License-Identifier: GPL-2.0+
> +
> +Sophgo
> +======
> +.. toctree::
> +   :maxdepth: 1
> +
> +   milkv_duo
> diff --git a/doc/board/sophgo/milkv_duo.rst b/doc/board/sophgo/milkv_duo.rst
> new file mode 100644
> index 0000000000..cb2ed1ad98
> --- /dev/null
> +++ b/doc/board/sophgo/milkv_duo.rst
> @@ -0,0 +1,64 @@
> +.. SPDX-License-Identifier: GPL-2.0+
> +
> +Milk-V Duo
> +==========
> +
> +CV1800B RISC-V SoC
> +------------------
> +The CV1800B is a high-performance, low-power 1+1 64-bit RISC-V SoC from Sophgo.
> +
> +Mainline support
> +----------------
> +The support for following drivers are already enabled:
> +1. ns16550 UART Driver.
> +
> +Building
> +~~~~~~~~
> +1. Add the RISC-V toolchain to your PATH.
> +2. Setup ARCH & cross compilation environment variable:
> +
> +.. code-block:: console
> +
> +   export CROSS_COMPILE=<riscv64 toolchain prefix>
> +   cd <U-Boot-dir>
> +   make milkv_duo_defconfig
> +   make
> +
> +This will generate u-boot-dtb.bin
> +
> +Booting
> +~~~~~~~
> +Currently, we rely on vendor FSBL(First Stage Boot Loader) to initialize the
> +clock and load the u-boot image, then bootup from it.
> +
> +Alternatively, to run u-boot-dtb.bin on top of FSBL, follow these steps:
> +
> +1. Use the vendor-provided tool to create a unified fip.bin file containing
> +   FSBL, OpenSBI, and U-Boot.

Hello Kongyang,

thank you for providing a documentation for the board.

Concerning the usage of fip.bin it would be helpful to add more detail:

* From where can the vendor code be downloaded?
* Which are the commands to execute?

Best regards

Heinrich

> +
> +2. Place the generated fip.bin file into the FAT partition of the SD card.
> +
> +3. Insert the SD card into the board and power it on.
> +
> +The board will automatically execute the FSBL from the fip.bin file.
> +Subsequently, it will transition to OpenSBI, and finally, OpenSBI will invoke
> +U-Boot.
> +
> +
> +Sample boot log from Milk-V Duo board
> +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> +.. code-block:: none
> +
> +   U-Boot 2024.01-rc5-00010-g51965baa36 (Dec 28 2023 - 13:15:53 +0800)milkv_duo
> +
> +   DRAM:  63.3 MiB
> +   Core:  10 devices, 8 uclasses, devicetree: separate
> +   Loading Environment from nowhere... OK
> +   In:    serial at 4140000
> +   Out:   serial at 4140000
> +   Err:   serial at 4140000
> +   Net:   No ethernet found.
> +   milkv_duo# cpu detail
> +     0: cpu at 0      rv64imafdc
> +      ID = 0, freq = 0 Hz: L1 cache, MMU
> +   milkv_duo#