Re: [PATCH v2] soc: qcom: ice: Add HWKM v1 support for wrapped keys

[Konrad Dybcio]

On 10/28/25 6:56 PM, Neeraj Soni wrote:
> HWKM v1 and v2 differ slightly in wrapped key size and the bit fields for
> certain status registers and operating mode (legacy or standard).
> 
> Add support to select HWKM version based on the major and minor revisions.
> Use this HWKM version to select wrapped key size and to configure the bit
> fields in registers for operating modes and hardware status.
> 
> Support for SCM calls for wrapped keys is being added in the TrustZone for
> few SoCs with HWKM v1. Existing check of qcom_scm_has_wrapped_key_support()
> API ensures that HWKM is used only if these SCM calls are supported in
> TrustZone for that SoC.
> 
> Signed-off-by: Neeraj Soni <neeraj.soni@xxxxxxxxxxxxxxxx>
> ---

[...]

> +	/* HWKM version v2 is present from ICE 3.2.1 onwards while version v1
> +	 * is present only in ICE 3.2.0. Earlier ICE version don't have HWKM.
> +	 */
> +	if (major > 3 ||
> +	   (major == 3 && (minor >= 3 || (minor == 2 && step >= 1))))
> +		ice->hwkm_version = QCOM_ICE_HWKM_V2;
> +	else if ((major == 3) && (minor == 2))
> +		ice->hwkm_version = QCOM_ICE_HWKM_V1;
> +	else
> +		ice->hwkm_version = 0;
> +
>  	dev_info(dev, "Found QC Inline Crypto Engine (ICE) v%d.%d.%d\n",
>  		 major, minor, step);
>  
> +	if (!ice->hwkm_version)
> +		dev_info(dev, "QC Hardware Key Manager (HWKM) not supported\n");

This isn't an error condition (ICE vers 3.0.0..<3.2.0 simply don't have it),
so I think it's fair not to print this possibly somewhat concerning message

[...]

>  static unsigned int translate_hwkm_slot(struct qcom_ice *ice, unsigned int slot)
>  {
> -	return slot * 2;
> +	/* The slot offset depends upon HWKM version */

This comment doesn't provide any additional context (e.g. what is the
underlying reason for V2 requiring a wider stride) - please provide
some or remove it, as otherwise it reiterates the single LoC below

Looks good otherwise

Konrad