Re: [PATCH v7 06/11] arm64: dts: imx93-11x11-evk: reserved mem-ranges

[Krzysztof Kozlowski]

On 30/10/2023 10:58, Pankaj Gupta wrote:
> EdgeLock Enclave are has a hardware limitation of restricted access
> to the DDR memory range:
> - 0x80000000  0x9FFFFFFF
> 
> ELE-MU driver requireis 1MB of memory. In this patch, reserving
> 1MB of ddr memory region from the lower 32-bit range.
> 
> Signed-off-by: Dong Aisheng <aisheng.dong@xxxxxxx>
> Signed-off-by: Pankaj Gupta <pankaj.gupta@xxxxxxx>
> ---
>  arch/arm64/boot/dts/freescale/imx93-11x11-evk.dts | 15 +++++++++++++++
>  1 file changed, 15 insertions(+)
> 
> diff --git a/arch/arm64/boot/dts/freescale/imx93-11x11-evk.dts b/arch/arm64/boot/dts/freescale/imx93-11x11-evk.dts
> index cafd39130eb8..bcb4ae931c64 100644
> --- a/arch/arm64/boot/dts/freescale/imx93-11x11-evk.dts
> +++ b/arch/arm64/boot/dts/freescale/imx93-11x11-evk.dts
> @@ -7,6 +7,10 @@
>  
>  #include "imx93.dtsi"
>  
> +&ele_fw2 {

OK, this explains the label in imx93.dtsi, but then node in the
imx93.dtsi is incomplete and should be disabled. Everything which is
incomplete should be disabled in DTSI by default. At v7 of your patchset
I really would expect some internal review happening.

> +	memory-region = <&ele_reserved>;
> +};
> +
>  / {
>  	model = "NXP i.MX93 11X11 EVK board";
>  	compatible = "fsl,imx93-11x11-evk", "fsl,imx93";
> @@ -68,6 +72,17 @@ reg_vref_1v8: regulator-adc-vref {
>  		regulator-max-microvolt = <1800000>;
>  	};
>  
> +	reserved-memory {
> +		#address-cells = <2>;
> +		#size-cells = <2>;
> +		ranges;
> +		ele_reserved: ele-reserved@a4120000 {

Names in reserved memory should match the purpose, so "reserved" is here
redundant. Just "ele".

> +			compatible = "shared-dma-pool";
> +			reg = <0 0xa4120000 0 0x100000>;
> +			no-map;
> +		};
> +	};
> +
>  	reg_usdhc2_vmmc: regulator-usdhc2 {
>  		compatible = "regulator-fixed";
>  		pinctrl-names = "default";

Best regards,
Krzysztof