Re: [PATCH v2 2/2] ARM: dts: Add nvmem node for BCM2711 bootloader public key

[Stefan Wahren]

Hi Ivan,

Am 13.04.23 um 10:52 schrieb Ivan T. Ivanov:
> From: Tim Gover <tim.gover@xxxxxxxxxxxxxxx>
>
> Make a copy of the bootloader secure-boot public key available to the OS
> via an nvmem node. The placement information is populated by the
> Raspberry Pi firmware if a public key is present in the BCM2711
> bootloader EEPROM.

It would be nice to have a helpful link like:
https://www.raspberrypi.com/documentation/computers/configuration.html#nvmem-nodes

> Signed-off-by: Tim Gover <tim.gover@xxxxxxxxxxxxxxx>
> Signed-off-by: Ivan T. Ivanov <iivanov@xxxxxxx>
> ---
>   arch/arm/boot/dts/bcm2711-rpi.dtsi | 14 ++++++++++++++
>   1 file changed, 14 insertions(+)
>
> diff --git a/arch/arm/boot/dts/bcm2711-rpi.dtsi b/arch/arm/boot/dts/bcm2711-rpi.dtsi
> index 98817a6675b9..e30fbe84f9c3 100644
> --- a/arch/arm/boot/dts/bcm2711-rpi.dtsi
> +++ b/arch/arm/boot/dts/bcm2711-rpi.dtsi
> @@ -15,6 +15,7 @@ aliases {
>   		ethernet0 = &genet;
>   		pcie0 = &pcie0;
>   		blconfig = &blconfig;
> +		blpubkey = &blpubkey;
>   	};
>   };
>   
> @@ -67,6 +68,19 @@ blconfig: nvram@0 {
>   		no-map;
>   		status = "disabled";
>   	};
> +
> +	/*
> +	 * RPi4 will copy the binary public key blob (if present) from the bootloader
> +	 * into memory for use by the OS.
> +	 */
> +	blpubkey: nvram@1 {
> +		compatible = "raspberrypi,bootloader-public-key", "nvmem-rmem";

Yes this looks better, but this introduce a new dtbs_check issue. The 
new compatible must be documented in 
Documentation/devicetree/bindings/nvmem/rmem.yaml in a separate patch 
and reviewed by the DT guys.

Btw better use linux-arm-kernel list instead of lkml

Best regards

> +		#address-cells = <1>;
> +		#size-cells = <1>;
> +		reg = <0x0 0x0 0x0>;
> +		no-map;
> +		status = "disabled";
> +	};
>   };
>   
>   &v3d {