From mboxrd@z Thu Jan  1 00:00:00 1970
From: gregory.clement@bootlin.com (Gregory CLEMENT)
Date: Thu, 05 Jul 2018 16:37:52 +0200
Subject: [PATCH] arm64: dts: marvell: a3700: reserve ATF memory
In-Reply-To: <1530801041-6909-1-git-send-email-arnaud.ferraris.external@sigfox.com>
 (Arnaud Ferraris's message of "Thu, 5 Jul 2018 16:30:41 +0200")
References: <1530801041-6909-1-git-send-email-arnaud.ferraris.external@sigfox.com>
Message-ID: <87bmbl21fj.fsf@bootlin.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

Hi Arnaud,
 
 On jeu., juil. 05 2018, Arnaud Ferraris <arnaud.ferraris.external@sigfox.com> wrote:

> On Marvell Armada 3700, the ARM Trusted Firmware is loaded in RAM at address
> 0x04000000, and can use up to 16MiB (0x01000000).
>
> As the ATF is responsible for handling PSCI calls (including, but not limited
> to, system reset management), its memory area should never be overwritten
> during runtime.
>
> Declaring a range of reserved memory solves this problem.

A similar patch[1] was applied last week in mvebu/dt64 and should be in
linux-next.

But keep in mind that U-Boot is supposed to update the reg value to
match your configuration.

http://lists.infradead.org/pipermail/linux-arm-kernel/2018-June/587408.html

Thanks,

Gregory

>
> Signed-off-by: Arnaud Ferraris <arnaud.ferraris.external@sigfox.com>
> ---
>  arch/arm64/boot/dts/marvell/armada-37xx.dtsi | 11 +++++++++++
>  1 file changed, 11 insertions(+)
>
> diff --git a/arch/arm64/boot/dts/marvell/armada-37xx.dtsi b/arch/arm64/boot/dts/marvell/armada-37xx.dtsi
> index 3353252..2110e7d 100644
> --- a/arch/arm64/boot/dts/marvell/armada-37xx.dtsi
> +++ b/arch/arm64/boot/dts/marvell/armada-37xx.dtsi
> @@ -34,6 +34,17 @@
>  		};
>  	};
>  
> +	reserved-memory {
> +		#address-cells = <2>;
> +		#size-cells = <2>;
> +		ranges;
> +
> +		arm-trusted-firmware at 4000000 {
> +			no-map;
> +			reg = <0x0 0x04000000 0x0 0x01000000>;
> +		};
> +	};
> +
>  	psci {
>  		compatible = "arm,psci-0.2";
>  		method = "smc";
> -- 
> 2.7.4
>

-- 
Gregory Clement, Bootlin (formerly Free Electrons)
Embedded Linux and Kernel engineering
http://bootlin.com