Re: [PATCH 2/2] board: sophgo: add support for Milk-V Duo 256M

[Yao Zi <me@ziyao.cc>]

On Fri, Jul 10, 2026 at 01:33:56PM -0300, Hiago De Franco wrote:
> Add U-Boot support for Milk-V Duo 256M.
> 
> This board has a different SoC compared to the Milk-V Duo 64M, it uses
> the Sophgo SG2002 instead of the Sophgo CV1800B. Both SoCs share many
> common IP blocks, so this board reuses the existing cv1800b CPU support.
> 
> Link: https://milkv.io/docs/duo/getting-started/duo256m
> Signed-off-by: Hiago De Franco <hfranco@baylibre.com>
> ---
>  arch/riscv/Kconfig                             |  4 ++
>  arch/riscv/dts/Makefile                        |  1 +
>  arch/riscv/dts/sg2002-milkv-duo256m.dts        | 46 +++++++++++++++
>  board/sophgo/milkv_duo_256m/Kconfig            | 30 ++++++++++
>  board/sophgo/milkv_duo_256m/MAINTAINERS        |  5 ++
>  board/sophgo/milkv_duo_256m/Makefile           |  6 ++
>  board/sophgo/milkv_duo_256m/board.c            | 19 ++++++
>  board/sophgo/milkv_duo_256m/milkv_duo_256m.env |  8 +++
>  configs/milkv_duo_256m_defconfig               | 42 +++++++++++++
>  doc/board/sophgo/index.rst                     |  1 +
>  doc/board/sophgo/milkv_duo_256m.rst            | 82 ++++++++++++++++++++++++++
>  include/configs/milkv_duo_256m.h               | 12 ++++
>  12 files changed, 256 insertions(+)

...

> diff --git a/board/sophgo/milkv_duo_256m/board.c b/board/sophgo/milkv_duo_256m/board.c
> new file mode 100644
> index 00000000000..b8454e0a1e9
> --- /dev/null
> +++ b/board/sophgo/milkv_duo_256m/board.c
> @@ -0,0 +1,19 @@
> +// SPDX-License-Identifier: GPL-2.0+
> +/*
> + * Copyright (c) 2026, Hiago De Franco <hfranco@baylibre.com>
> + */
> +
> +#include <dm/lists.h>
> +
> +#include "../common/ethernet.h"
> +
> +int board_init(void)
> +{
> +	if (IS_ENABLED(CONFIG_SYSRESET_CV1800B))
> +		device_bind_driver(gd->dm_root, "cv1800b_sysreset", "sysreset", NULL);
> +
> +	if (IS_ENABLED(CONFIG_NET_LEGACY))
> +		cv1800b_ephy_init();
> +
> +	return 0;
> +}

This looks identical to milkv_duo/board.c, could we re-use it instead of
introducing a copy at least for now?

...

> diff --git a/doc/board/sophgo/milkv_duo_256m.rst b/doc/board/sophgo/milkv_duo_256m.rst
> new file mode 100644
> index 00000000000..671f3a0b964
> --- /dev/null
> +++ b/doc/board/sophgo/milkv_duo_256m.rst
> @@ -0,0 +1,82 @@
> +.. SPDX-License-Identifier: GPL-2.0+
> +
> +Milk-V Duo 256M
> +===============
> +
> +SG2002 RISC-V SoC
> +------------------
> +The SG2002 is a high-performance, low-power 64-bit RISC-V/ARM SoC from Sophgo.
> +
> +Mainline support
> +----------------
> +The support for following drivers are already enabled:
> +1. ns16550 UART Driver.
> +2. Synopsys Designware MSHC Driver

At least this part is not accurate, according to the log below,

...

> +Sample boot log from Milk-V 256M Duo board
> +~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> +.. code-block:: none
> +
> +  U-Boot 2026.07-00002-g0b690770386f-dirty (Jul 07 2026 - 13:33:36 -0300)milkv_duo_256m
> +
> +  DRAM:  256 MiB
> +  Core:  20 devices, 13 uclasses, devicetree: separate
> +  MMC:   mmc@4310000: 0
> +  Loading Environment from nowhere... OK
> +  In:    serial@4140000
> +  Out:   serial@4140000
> +  Err:   serial@4140000
> +  Net:
> +  Warning: ethernet@4070000 (eth0) using random MAC address - 0a:f3:23:40:7e:55

Ethernet is enabled, too. Please update the documentation to reflect the
support status.

Best regards,
Yao Zi