[Intel-gfx] [PATCH] drm/i915: terminate reauth at stream management failure

[Anshuman Gupta]

On 2020-02-10 at 22:19:50 +0530, Ramalingam C wrote:
> As per the HDCP2.2 compliance test 1B-10 expectation, when stream
> management for a repeater fails, HDCP2.2 reauthentication stops at
> kernel.
Shall i drop my patch now and continue with reviewing this patch.
one comment below.
> 
> Signed-off-by: Ramalingam C <ramalingam.c at intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_hdcp.c | 55 ++++++++++++++---------
>  1 file changed, 34 insertions(+), 21 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c
> index 4d1a33d13105..5ab35484da93 100644
> --- a/drivers/gpu/drm/i915/display/intel_hdcp.c
> +++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
> @@ -1380,7 +1380,7 @@ static int hdcp2_session_key_exchange(struct intel_connector *connector)
>  }
>  
>  static
> -int hdcp2_propagate_stream_management_info(struct intel_connector *connector)
> +int _hdcp2_propagate_stream_management_info(struct intel_connector *connector)
>  {
>  	struct intel_digital_port *intel_dig_port = intel_attached_dig_port(connector);
>  	struct intel_hdcp *hdcp = &connector->hdcp;
> @@ -1492,17 +1492,6 @@ int hdcp2_authenticate_repeater_topology(struct intel_connector *connector)
>  	return 0;
>  }
>  
> -static int hdcp2_authenticate_repeater(struct intel_connector *connector)
> -{
> -	int ret;
> -
> -	ret = hdcp2_authenticate_repeater_topology(connector);
> -	if (ret < 0)
> -		return ret;
> -
> -	return hdcp2_propagate_stream_management_info(connector);
> -}
> -
>  static int hdcp2_authenticate_sink(struct intel_connector *connector)
>  {
>  	struct intel_digital_port *intel_dig_port = intel_attached_dig_port(connector);
> @@ -1537,18 +1526,13 @@ static int hdcp2_authenticate_sink(struct intel_connector *connector)
>  	}
>  
>  	if (hdcp->is_repeater) {
> -		ret = hdcp2_authenticate_repeater(connector);
> +		ret = hdcp2_authenticate_repeater_topology(connector);
>  		if (ret < 0) {
>  			DRM_DEBUG_KMS("Repeater Auth Failed. Err: %d\n", ret);
>  			return ret;
>  		}
>  	}
>  
> -	hdcp->port_data.streams[0].stream_type = hdcp->content_type;
> -	ret = hdcp2_authenticate_port(connector);
> -	if (ret < 0)
> -		return ret;
> -
>  	return ret;
>  }
>  
> @@ -1626,14 +1610,43 @@ static int hdcp2_disable_encryption(struct intel_connector *connector)
>  	return ret;
>  }
>  
> +static int
> +hdcp2_propagate_stream_management_info(struct intel_connector *connector)
> +{
> +	int i, tries = 3, ret;
> +
> +	if (!connector->hdcp.is_repeater)
> +		return 0;
> +
> +	for (i = 0; i < tries; i++) {
> +		ret = _hdcp2_propagate_stream_management_info(connector);
> +		if (!ret)
> +			break;
> +	}
> +
> +	return ret;
> +}
> +
>  static int hdcp2_authenticate_and_encrypt(struct intel_connector *connector)
>  {
> +	struct intel_hdcp *hdcp = &connector->hdcp;
>  	int ret, i, tries = 3;
>  
>  	for (i = 0; i < tries; i++) {
>  		ret = hdcp2_authenticate_sink(connector);
> -		if (!ret)
> -			break;
> +		if (!ret) {
> +			ret = hdcp2_propagate_stream_management_info(connector);
			we need to increment seq_num_m fo every retry of stream management.
Thanks,
Anshuman Gupta.
> +			if (!ret) {
> +				hdcp->port_data.streams[0].stream_type =
> +							hdcp->content_type;
> +				ret = hdcp2_authenticate_port(connector);
> +				if (!ret)
> +					break;
> +			} else {
> +				DRM_DEBUG_KMS("HDCP2 stream management failed\n");
> +				break;
> +			}
> +		}
>  
>  		/* Clearing the mei hdcp session */
>  		DRM_DEBUG_KMS("HDCP2.2 Auth %d of %d Failed.(%d)\n",
> @@ -1642,7 +1655,7 @@ static int hdcp2_authenticate_and_encrypt(struct intel_connector *connector)
>  			DRM_DEBUG_KMS("Port deauth failed.\n");
>  	}
>  
> -	if (i != tries) {
> +	if (!ret) {
>  		/*
>  		 * Ensuring the required 200mSec min time interval between
>  		 * Session Key Exchange and encryption.
> -- 
> 2.20.1
>