Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.38 as permitted sender) client-ip=23.128.96.38;
Date:   Mon, 16 Oct 2023 09:37:31 +0200
From:   Stephan Gerhold <stephan@gerhold.net>
To:     Luca Weiss <luca@z3ntu.xyz>
Cc:     ~postmarketos/upstreaming@lists.sr.ht, phone-devel@vger.kernel.org,
        Andy Gross <agross@kernel.org>,
        Bjorn Andersson <andersson@kernel.org>,
        Konrad Dybcio <konrad.dybcio@linaro.org>,
        Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>,
        Conor Dooley <conor+dt@kernel.org>,
        linux-arm-msm@vger.kernel.org, devicetree@vger.kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH 1/2] arm64: dts: qcom: msm8953: Set initial address for
 memory
Message-ID: <ZSzoO9QhwVmL8jLk@gerhold.net>
References: <20231015-msm8953-misc-fixes-v1-0-b800deca9e46@z3ntu.xyz>
 <20231015-msm8953-misc-fixes-v1-1-b800deca9e46@z3ntu.xyz>
MIME-Version: 1.0
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
In-Reply-To: <20231015-msm8953-misc-fixes-v1-1-b800deca9e46@z3ntu.xyz>
Content-Transfer-Encoding: 7bit
Precedence: bulk

On Sun, Oct 15, 2023 at 10:26:01PM +0200, Luca Weiss wrote:
> The dtbs_check really doesn't like having memory without reg set.
> Address this by setting it to 0x10000000 which seems to be the value
> filled in by the bootloader.
> 

Looks like MSM8953 has the same RAM setup as MSM8916, where the base
address depends on the amount of RAM you have:

  <= 2.00 GiB RAM: 0x80000000
   = 3.00 GiB RAM: 0x40000000
   = 3.75 GiB RAM: 0x10000000
 (more does not fit into the 32-bit physical address space)

So, 0x10000000 will only end up being used on devices with 3.75 GiB RAM.

Can you add a note about this in the commit message maybe? We don't know
in advance which base address a device will use, so I think it's fine to
hardcode one of the choices by default. msm8916.dtsi does the same.

Thanks,
Stephan

> Signed-off-by: Luca Weiss <luca@z3ntu.xyz>
> ---
>  arch/arm64/boot/dts/qcom/msm8953.dtsi | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/arch/arm64/boot/dts/qcom/msm8953.dtsi b/arch/arm64/boot/dts/qcom/msm8953.dtsi
> index e7de7632669a..a3ba24ca599b 100644
> --- a/arch/arm64/boot/dts/qcom/msm8953.dtsi
> +++ b/arch/arm64/boot/dts/qcom/msm8953.dtsi
> @@ -174,10 +174,10 @@ scm: scm {
>  		};
>  	};
>  
> -	memory {
> +	memory@10000000 {
>  		device_type = "memory";
>  		/* We expect the bootloader to fill in the reg */
> -		reg = <0 0 0 0>;
> +		reg = <0 0x10000000 0 0>;
>  	};
>  
>  	pmu {
> 
> -- 
> 2.42.0
>