Re: [PATCH v2 7/8] arm64: dts: marvell: Add Armada 98DX2530 SoC and RD-AC5X board

From: Andrew Lunn <andrew@lunn.ch>
To: Chris Packham <Chris.Packham@alliedtelesis.co.nz>
Cc: "robh+dt@kernel.org" <robh+dt@kernel.org>,
	"gregory.clement@bootlin.com" <gregory.clement@bootlin.com>,
	"sebastian.hesselbarth@gmail.com"
	<sebastian.hesselbarth@gmail.com>,
	"devicetree@vger.kernel.org" <devicetree@vger.kernel.org>,
	"linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
	"linux-arm-kernel@lists.infradead.org" 
	<linux-arm-kernel@lists.infradead.org>
Subject: Re: [PATCH v2 7/8] arm64: dts: marvell: Add Armada 98DX2530 SoC and RD-AC5X board
Date: Tue, 15 Mar 2022 15:28:50 +0100	[thread overview]
Message-ID: <YjCiot+PSv3ZRS4J@lunn.ch> (raw)
In-Reply-To: <7b78853e-71ec-7c57-4cac-5cd6303f3b13@alliedtelesis.co.nz>

On Tue, Mar 15, 2022 at 02:11:56AM +0000, Chris Packham wrote:
> 
> On 15/03/22 13:24, Andrew Lunn wrote:
> >> diff --git a/arch/arm64/boot/dts/marvell/armada-98dx2530.dtsi b/arch/arm64/boot/dts/marvell/armada-98dx2530.dtsi
> >> new file mode 100644
> >> index 000000000000..ebe464b9ebd2
> >> --- /dev/null
> >> +++ b/arch/arm64/boot/dts/marvell/armada-98dx2530.dtsi
> >> @@ -0,0 +1,343 @@
> >> +// SPDX-License-Identifier: (GPL-2.0+ OR MIT)
> >> +/*
> >> + * Device Tree For AC5.
> >> + *
> >> + * Copyright (C) 2021 Marvell
> >> + *
> >> + */
> >> +
> >> +/dts-v1/;
> >> +	memory@0 {
> >> +		device_type = "memory";
> >> +		reg = <0x2 0x00000000 0x0 0x40000000>;
> >> +		// linux,usable-memory = <0x2 0x00000000 0x0 0x80000000>;
> >> +	};
> > Is the memory part of the SoC, or is it on the board? Normally it is
> > on the board, so should be in the .dts file. But Apple M1 etc...

> I also wasn't sure about linux,usable-memory. It's commented out so it's 
> obviously doing nothing but should it? No other in-tree dts files have it.

Hi Chris

I've no idea what it means. Maybe search the SDK and see if they have
some code and what it does. But i would drop it.

     Andrew