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Date:   Thu, 16 Mar 2023 15:17:07 +0100
From:   "Arnd Bergmann" <arnd@arndb.de>
To:     "Jacky Huang" <ychuang570808@gmail.com>,
        "Rob Herring" <robh+dt@kernel.org>,
        krzysztof.kozlowski+dt@linaro.org, "Lee Jones" <lee@kernel.org>,
        "Michael Turquette" <mturquette@baylibre.com>,
        "Stephen Boyd" <sboyd@kernel.org>,
        "Philipp Zabel" <p.zabel@pengutronix.de>,
        "Greg Kroah-Hartman" <gregkh@linuxfoundation.org>,
        "Jiri Slaby" <jirislaby@kernel.org>
Cc:     devicetree@vger.kernel.org, linux-clk@vger.kernel.org,
        linux-kernel@vger.kernel.org, linux-serial@vger.kernel.org,
        schung@nuvoton.com, "Jacky Huang" <ychuang3@nuvoton.com>
Subject: Re: [PATCH 11/15] arm64: dts: nuvoton: Add initial ma35d1 device tree
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On Wed, Mar 15, 2023, at 08:28, Jacky Huang wrote:
> +	mem: memory@80000000 {
> +		device_type = "memory";
> +		reg = <0x00000000 0x80000000 0 0x20000000>; /* 512M DRAM */
> +	};
> +};

In most machines, the memory size is detected by the boot loader
and filled in the dtb in memory before starting the kernel, so
you should not need two separate files here for the two common
memory configurations.

Since the machine is called 'som', I would assume that this is a
module that is integrated on another board, so more commonly one
would have a dtsi file for the som in addition to the one for the
soc, and have all the components of the module listed in this
file, while the dts file that includes the som.dtsi lists the
devices on the carrier board and enables the on-chip devices
that are connected to the outside.

       Arnd