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Date:   Sat, 12 Jun 2021 15:53:47 +0800
From:   Shawn Guo <shawnguo@kernel.org>
To:     Vladimir Oltean <olteanv@gmail.com>
Cc:     devicetree@vger.kernel.org, Li Yang <leoyang.li@nxp.com>,
        Rob Herring <robh+dt@kernel.org>,
        linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org,
        Vladimir Oltean <vladimir.oltean@nxp.com>
Subject: Re: [PATCH] arm64: dts: fix node name for the sysclk
Message-ID: <20210612075346.GZ29138@dragon>
References: <20210608112658.4087235-1-olteanv@gmail.com>
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On Tue, Jun 08, 2021 at 02:26:58PM +0300, Vladimir Oltean wrote:
> From: Vladimir Oltean <vladimir.oltean@nxp.com>
> 
> U-Boot attempts to fix up the "clock-frequency" property of the "/sysclk" node:
> https://elixir.bootlin.com/u-boot/v2021.04/source/arch/arm/cpu/armv8/fsl-layerscape/fdt.c#L512
> 
> but fails to do so:
> 
>   ## Booting kernel from Legacy Image at a1000000 ...
>      Image Name:
>      Created:      2021-06-08  10:31:38 UTC
>      Image Type:   AArch64 Linux Kernel Image (gzip compressed)
>      Data Size:    15431370 Bytes = 14.7 MiB
>      Load Address: 80080000
>      Entry Point:  80080000
>      Verifying Checksum ... OK
>   ## Flattened Device Tree blob at a0000000
>      Booting using the fdt blob at 0xa0000000
>      Uncompressing Kernel Image
>      Loading Device Tree to 00000000fbb19000, end 00000000fbb22717 ... OK
>   Unable to update property /sysclk:clock-frequency, err=FDT_ERR_NOTFOUND
> 
>   Starting kernel ...
> 
> All Layerscape SoCs except LS1028A use "sysclk" as the node name, and
> not "clock-sysclk". So change the node name of LS1028A accordingly.

Wouldn't it more flexible to use alias/label for finding the node?
Using node name/path looks fragile. 

Shawn

> 
> Fixes: 8897f3255c9c ("arm64: dts: Add support for NXP LS1028A SoC")
> Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
> ---
>  arch/arm64/boot/dts/freescale/fsl-ls1028a.dtsi | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/arch/arm64/boot/dts/freescale/fsl-ls1028a.dtsi b/arch/arm64/boot/dts/freescale/fsl-ls1028a.dtsi
> index d0dddf19578a..03e1ca7fea9a 100644
> --- a/arch/arm64/boot/dts/freescale/fsl-ls1028a.dtsi
> +++ b/arch/arm64/boot/dts/freescale/fsl-ls1028a.dtsi
> @@ -66,7 +66,7 @@ CPU_PW20: cpu-pw20 {
>  		};
>  	};
>  
> -	sysclk: clock-sysclk {
> +	sysclk: sysclk {
>  		compatible = "fixed-clock";
>  		#clock-cells = <0>;
>  		clock-frequency = <100000000>;
> -- 
> 2.25.1
>