diff mbox series

[v3,07/16] drm/i915/hdcp: Enable Gen12 HDCP 1.4 DP MST support

Message ID 20201023122112.15265-8-anshuman.gupta@intel.com
State New, archived
Headers show
Series [v3,01/16] drm/i915/hdcp: Update CP property in update_pipe | expand

Commit Message

Anshuman Gupta Oct. 23, 2020, 12:21 p.m. UTC
Enable HDCP 1.4 over DP MST for Gen12.
This also enable the stream encryption support for
older generations, which was missing earlier.

v2:
- Added debug print for stream encryption.
- Disable the hdcp on port after disabling last stream
  encryption.

Cc: Ramalingam C <ramalingam.c@intel.com>
Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
---
 drivers/gpu/drm/i915/display/intel_dp_mst.c | 10 ++---
 drivers/gpu/drm/i915/display/intel_hdcp.c   | 46 ++++++++++++++-------
 2 files changed, 35 insertions(+), 21 deletions(-)

Comments

Uma Shankar Oct. 27, 2020, 6:29 a.m. UTC | #1
> -----Original Message-----
> From: Anshuman Gupta <anshuman.gupta@intel.com>
> Sent: Friday, October 23, 2020 5:51 PM
> To: intel-gfx@lists.freedesktop.org; dri-devel@lists.freedesktop.org
> Cc: seanpaul@chromium.org; Nikula, Jani <jani.nikula@intel.com>; C,
> Ramalingam <ramalingam.c@intel.com>; Li, Juston <juston.li@intel.com>;
> Shankar, Uma <uma.shankar@intel.com>; Gupta, Anshuman
> <anshuman.gupta@intel.com>
> Subject: [PATCH v3 07/16] drm/i915/hdcp: Enable Gen12 HDCP 1.4 DP MST
> support
> 
> Enable HDCP 1.4 over DP MST for Gen12.
> This also enable the stream encryption support for older generations, which was
> missing earlier.
> 
> v2:
> - Added debug print for stream encryption.
> - Disable the hdcp on port after disabling last stream
>   encryption.

Don't see port disable here, Am I missing something.

> 
> Cc: Ramalingam C <ramalingam.c@intel.com>
> Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
> ---
>  drivers/gpu/drm/i915/display/intel_dp_mst.c | 10 ++---
>  drivers/gpu/drm/i915/display/intel_hdcp.c   | 46 ++++++++++++++-------
>  2 files changed, 35 insertions(+), 21 deletions(-)
> 
> diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> index 16865b200062..f00e12fc83e8 100644
> --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> @@ -826,13 +826,9 @@ static struct drm_connector
> *intel_dp_add_mst_connector(struct drm_dp_mst_topolo
>  	intel_attach_force_audio_property(connector);
>  	intel_attach_broadcast_rgb_property(connector);
> 
> -
> -	/* TODO: Figure out how to make HDCP work on GEN12+ */
> -	if (INTEL_GEN(dev_priv) < 12) {
> -		ret = intel_dp_init_hdcp(dig_port, intel_connector);
> -		if (ret)
> -			DRM_DEBUG_KMS("HDCP init failed, skipping.\n");
> -	}
> +	ret = intel_dp_init_hdcp(dig_port, intel_connector);
> +	if (ret)
> +		drm_dbg_kms(&dev_priv->drm, "HDCP init failed, skipping.\n");
> 
>  	/*
>  	 * Reuse the prop from the SST connector because we're diff --git
> a/drivers/gpu/drm/i915/display/intel_hdcp.c
> b/drivers/gpu/drm/i915/display/intel_hdcp.c
> index 61252d4be3dd..46c9bd588db1 100644
> --- a/drivers/gpu/drm/i915/display/intel_hdcp.c
> +++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
> @@ -612,7 +612,12 @@ int intel_hdcp_auth_downstream(struct intel_connector
> *connector)
>  	return ret;
>  }
> 
> -/* Implements Part 1 of the HDCP authorization procedure */
> +/*
> + * Implements Part 1 of the HDCP authorization procedure.
> + * Authentication Part 1 steps for Multi-stream DisplayPort.
> + * Step 1. Auth Part 1 sequence on the driving MST Trasport Link.
> + * Step 2. Enable encryption for each stream that requires encryption.
> + */
>  static int intel_hdcp_auth(struct intel_connector *connector)  {
>  	struct intel_digital_port *dig_port = intel_attached_dig_port(connector);
> @@ -766,10 +771,16 @@ static int intel_hdcp_auth(struct intel_connector
> *connector)
>  		return -ETIMEDOUT;
>  	}
> 
> -	/*
> -	 * XXX: If we have MST-connected devices, we need to enable encryption
> -	 * on those as well.
> -	 */
> +	/* DP MST Auth Part 1 Step 2.a and Step 2.b */
> +	if (shim->stream_encryption) {
> +		ret = shim->stream_encryption(dig_port, true);
> +		if (ret) {
> +			drm_err(&dev_priv->drm, "Failed to enable HDCP 1.4
> stream enc\n");
> +			return ret;
> +		}
> +		drm_dbg_kms(&dev_priv->drm, "HDCP 1.4 tras %s stream
> encrypted\n",
> +			    transcoder_name(hdcp->stream_transcoder));
> +	}
> 
>  	if (repeater_present)
>  		return intel_hdcp_auth_downstream(connector);
> @@ -790,19 +801,26 @@ static int _intel_hdcp_disable(struct intel_connector
> *connector)
> 
>  	drm_dbg_kms(&dev_priv->drm, "[%s:%d] HDCP is being disabled...\n",
>  		    connector->base.name, connector->base.base.id);
> +	/*
> +	 * Step 1: Deselect HDCP Multiplestream Bit.
> +	 * Step 2: poll for stream encryption status to be disable.
> +	 */

The above comment should be inside the callback, doesn't add value here.

> +	if (hdcp->shim->stream_encryption) {
> +		ret = hdcp->shim->stream_encryption(dig_port, false);
> +		if (ret) {
> +			drm_err(&dev_priv->drm, "Failed to disable HDCP 1.4
> stream enc\n");
> +			return ret;
> +		}
> +		drm_dbg_kms(&dev_priv->drm, "HDCP 1.4 trans %s stream
> encryption disabled\n",
> +			    transcoder_name(hdcp->stream_transcoder));
> +	}
> 
>  	/*
> -	 * If there are other connectors on this port using HDCP, don't disable
> -	 * it. Instead, toggle the HDCP signalling off on that particular
> -	 * connector/pipe and exit.
> +	 * If there are other connectors on this port using HDCP, don't disable it.
> +	 * Repeat steps 1-2 for each stream that no longer requires encryption.
>  	 */
> -	if (dig_port->num_hdcp_streams > 0) {
> -		ret = hdcp->shim->toggle_signalling(dig_port,
> -						    cpu_transcoder, false);
> -		if (ret)
> -			DRM_ERROR("Failed to disable HDCP signalling\n");
> +	if (dig_port->num_hdcp_streams > 0)
>  		return ret;
> -	}
> 
>  	hdcp->hdcp_encrypted = false;
>  	intel_de_write(dev_priv, HDCP_CONF(dev_priv, cpu_transcoder, port), 0);
> --
> 2.26.2
Anshuman Gupta Oct. 27, 2020, 7:57 a.m. UTC | #2
On 2020-10-27 at 11:59:14 +0530, Shankar, Uma wrote:
> 
> 
> > -----Original Message-----
> > From: Anshuman Gupta <anshuman.gupta@intel.com>
> > Sent: Friday, October 23, 2020 5:51 PM
> > To: intel-gfx@lists.freedesktop.org; dri-devel@lists.freedesktop.org
> > Cc: seanpaul@chromium.org; Nikula, Jani <jani.nikula@intel.com>; C,
> > Ramalingam <ramalingam.c@intel.com>; Li, Juston <juston.li@intel.com>;
> > Shankar, Uma <uma.shankar@intel.com>; Gupta, Anshuman
> > <anshuman.gupta@intel.com>
> > Subject: [PATCH v3 07/16] drm/i915/hdcp: Enable Gen12 HDCP 1.4 DP MST
> > support
> > 
> > Enable HDCP 1.4 over DP MST for Gen12.
> > This also enable the stream encryption support for older generations, which was
> > missing earlier.
> > 
> > v2:
> > - Added debug print for stream encryption.
> > - Disable the hdcp on port after disabling last stream
> >   encryption.
> 
> Don't see port disable here, Am I missing something.
Do u mean disbaling HDCP for a port ?
That is being done when dig_port->num_hdcp_streams are zero,
then it disbale the HDCP for entire port.
My earlier version of this patch was missing below hunk
if (dig_port->num_hdcp_streams > 0)
	return ret;
I will fix the other cosmetics comment on this patch.
Thanks,
Anshuman Gupta.
> 
> > 
> > Cc: Ramalingam C <ramalingam.c@intel.com>
> > Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_dp_mst.c | 10 ++---
> >  drivers/gpu/drm/i915/display/intel_hdcp.c   | 46 ++++++++++++++-------
> >  2 files changed, 35 insertions(+), 21 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> > b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> > index 16865b200062..f00e12fc83e8 100644
> > --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> > +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> > @@ -826,13 +826,9 @@ static struct drm_connector
> > *intel_dp_add_mst_connector(struct drm_dp_mst_topolo
> >  	intel_attach_force_audio_property(connector);
> >  	intel_attach_broadcast_rgb_property(connector);
> > 
> > -
> > -	/* TODO: Figure out how to make HDCP work on GEN12+ */
> > -	if (INTEL_GEN(dev_priv) < 12) {
> > -		ret = intel_dp_init_hdcp(dig_port, intel_connector);
> > -		if (ret)
> > -			DRM_DEBUG_KMS("HDCP init failed, skipping.\n");
> > -	}
> > +	ret = intel_dp_init_hdcp(dig_port, intel_connector);
> > +	if (ret)
> > +		drm_dbg_kms(&dev_priv->drm, "HDCP init failed, skipping.\n");
> > 
> >  	/*
> >  	 * Reuse the prop from the SST connector because we're diff --git
> > a/drivers/gpu/drm/i915/display/intel_hdcp.c
> > b/drivers/gpu/drm/i915/display/intel_hdcp.c
> > index 61252d4be3dd..46c9bd588db1 100644
> > --- a/drivers/gpu/drm/i915/display/intel_hdcp.c
> > +++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
> > @@ -612,7 +612,12 @@ int intel_hdcp_auth_downstream(struct intel_connector
> > *connector)
> >  	return ret;
> >  }
> > 
> > -/* Implements Part 1 of the HDCP authorization procedure */
> > +/*
> > + * Implements Part 1 of the HDCP authorization procedure.
> > + * Authentication Part 1 steps for Multi-stream DisplayPort.
> > + * Step 1. Auth Part 1 sequence on the driving MST Trasport Link.
> > + * Step 2. Enable encryption for each stream that requires encryption.
> > + */
> >  static int intel_hdcp_auth(struct intel_connector *connector)  {
> >  	struct intel_digital_port *dig_port = intel_attached_dig_port(connector);
> > @@ -766,10 +771,16 @@ static int intel_hdcp_auth(struct intel_connector
> > *connector)
> >  		return -ETIMEDOUT;
> >  	}
> > 
> > -	/*
> > -	 * XXX: If we have MST-connected devices, we need to enable encryption
> > -	 * on those as well.
> > -	 */
> > +	/* DP MST Auth Part 1 Step 2.a and Step 2.b */
> > +	if (shim->stream_encryption) {
> > +		ret = shim->stream_encryption(dig_port, true);
> > +		if (ret) {
> > +			drm_err(&dev_priv->drm, "Failed to enable HDCP 1.4
> > stream enc\n");
> > +			return ret;
> > +		}
> > +		drm_dbg_kms(&dev_priv->drm, "HDCP 1.4 tras %s stream
> > encrypted\n",
> > +			    transcoder_name(hdcp->stream_transcoder));
> > +	}
> > 
> >  	if (repeater_present)
> >  		return intel_hdcp_auth_downstream(connector);
> > @@ -790,19 +801,26 @@ static int _intel_hdcp_disable(struct intel_connector
> > *connector)
> > 
> >  	drm_dbg_kms(&dev_priv->drm, "[%s:%d] HDCP is being disabled...\n",
> >  		    connector->base.name, connector->base.base.id);
> > +	/*
> > +	 * Step 1: Deselect HDCP Multiplestream Bit.
> > +	 * Step 2: poll for stream encryption status to be disable.
> > +	 */
> 
> The above comment should be inside the callback, doesn't add value here.
> 
> > +	if (hdcp->shim->stream_encryption) {
> > +		ret = hdcp->shim->stream_encryption(dig_port, false);
> > +		if (ret) {
> > +			drm_err(&dev_priv->drm, "Failed to disable HDCP 1.4
> > stream enc\n");
> > +			return ret;
> > +		}
> > +		drm_dbg_kms(&dev_priv->drm, "HDCP 1.4 trans %s stream
> > encryption disabled\n",
> > +			    transcoder_name(hdcp->stream_transcoder));
> > +	}
> > 
> >  	/*
> > -	 * If there are other connectors on this port using HDCP, don't disable
> > -	 * it. Instead, toggle the HDCP signalling off on that particular
> > -	 * connector/pipe and exit.
> > +	 * If there are other connectors on this port using HDCP, don't disable it.
> > +	 * Repeat steps 1-2 for each stream that no longer requires encryption.
> >  	 */
> > -	if (dig_port->num_hdcp_streams > 0) {
> > -		ret = hdcp->shim->toggle_signalling(dig_port,
> > -						    cpu_transcoder, false);
> > -		if (ret)
> > -			DRM_ERROR("Failed to disable HDCP signalling\n");
> > +	if (dig_port->num_hdcp_streams > 0)
> >  		return ret;
> > -	}
> > 
> >  	hdcp->hdcp_encrypted = false;
> >  	intel_de_write(dev_priv, HDCP_CONF(dev_priv, cpu_transcoder, port), 0);
> > --
> > 2.26.2
>
Anshuman Gupta Oct. 27, 2020, 12:04 p.m. UTC | #3
On 2020-10-27 at 11:59:14 +0530, Shankar, Uma wrote:
> 
> 
> > -----Original Message-----
> > From: Anshuman Gupta <anshuman.gupta@intel.com>
> > Sent: Friday, October 23, 2020 5:51 PM
> > To: intel-gfx@lists.freedesktop.org; dri-devel@lists.freedesktop.org
> > Cc: seanpaul@chromium.org; Nikula, Jani <jani.nikula@intel.com>; C,
> > Ramalingam <ramalingam.c@intel.com>; Li, Juston <juston.li@intel.com>;
> > Shankar, Uma <uma.shankar@intel.com>; Gupta, Anshuman
> > <anshuman.gupta@intel.com>
> > Subject: [PATCH v3 07/16] drm/i915/hdcp: Enable Gen12 HDCP 1.4 DP MST
> > support
> > 
> > Enable HDCP 1.4 over DP MST for Gen12.
> > This also enable the stream encryption support for older generations, which was
> > missing earlier.
> > 
> > v2:
> > - Added debug print for stream encryption.
> > - Disable the hdcp on port after disabling last stream
> >   encryption.
> 
> Don't see port disable here, Am I missing something.
> 
> > 
> > Cc: Ramalingam C <ramalingam.c@intel.com>
> > Signed-off-by: Anshuman Gupta <anshuman.gupta@intel.com>
> > ---
> >  drivers/gpu/drm/i915/display/intel_dp_mst.c | 10 ++---
> >  drivers/gpu/drm/i915/display/intel_hdcp.c   | 46 ++++++++++++++-------
> >  2 files changed, 35 insertions(+), 21 deletions(-)
> > 
> > diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> > b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> > index 16865b200062..f00e12fc83e8 100644
> > --- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
> > +++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
> > @@ -826,13 +826,9 @@ static struct drm_connector
> > *intel_dp_add_mst_connector(struct drm_dp_mst_topolo
> >  	intel_attach_force_audio_property(connector);
> >  	intel_attach_broadcast_rgb_property(connector);
> > 
> > -
> > -	/* TODO: Figure out how to make HDCP work on GEN12+ */
> > -	if (INTEL_GEN(dev_priv) < 12) {
> > -		ret = intel_dp_init_hdcp(dig_port, intel_connector);
> > -		if (ret)
> > -			DRM_DEBUG_KMS("HDCP init failed, skipping.\n");
> > -	}
> > +	ret = intel_dp_init_hdcp(dig_port, intel_connector);
> > +	if (ret)
> > +		drm_dbg_kms(&dev_priv->drm, "HDCP init failed, skipping.\n");
> > 
> >  	/*
> >  	 * Reuse the prop from the SST connector because we're diff --git
> > a/drivers/gpu/drm/i915/display/intel_hdcp.c
> > b/drivers/gpu/drm/i915/display/intel_hdcp.c
> > index 61252d4be3dd..46c9bd588db1 100644
> > --- a/drivers/gpu/drm/i915/display/intel_hdcp.c
> > +++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
> > @@ -612,7 +612,12 @@ int intel_hdcp_auth_downstream(struct intel_connector
> > *connector)
> >  	return ret;
> >  }
> > 
> > -/* Implements Part 1 of the HDCP authorization procedure */
> > +/*
> > + * Implements Part 1 of the HDCP authorization procedure.
> > + * Authentication Part 1 steps for Multi-stream DisplayPort.
> > + * Step 1. Auth Part 1 sequence on the driving MST Trasport Link.
> > + * Step 2. Enable encryption for each stream that requires encryption.
> > + */
> >  static int intel_hdcp_auth(struct intel_connector *connector)  {
> >  	struct intel_digital_port *dig_port = intel_attached_dig_port(connector);
> > @@ -766,10 +771,16 @@ static int intel_hdcp_auth(struct intel_connector
> > *connector)
> >  		return -ETIMEDOUT;
> >  	}
> > 
> > -	/*
> > -	 * XXX: If we have MST-connected devices, we need to enable encryption
> > -	 * on those as well.
> > -	 */
> > +	/* DP MST Auth Part 1 Step 2.a and Step 2.b */
> > +	if (shim->stream_encryption) {
> > +		ret = shim->stream_encryption(dig_port, true);
> > +		if (ret) {
> > +			drm_err(&dev_priv->drm, "Failed to enable HDCP 1.4
> > stream enc\n");
> > +			return ret;
> > +		}
> > +		drm_dbg_kms(&dev_priv->drm, "HDCP 1.4 tras %s stream
> > encrypted\n",
> > +			    transcoder_name(hdcp->stream_transcoder));
> > +	}
> > 
> >  	if (repeater_present)
> >  		return intel_hdcp_auth_downstream(connector);
> > @@ -790,19 +801,26 @@ static int _intel_hdcp_disable(struct intel_connector
> > *connector)
> > 
> >  	drm_dbg_kms(&dev_priv->drm, "[%s:%d] HDCP is being disabled...\n",
> >  		    connector->base.name, connector->base.base.id);
> > +	/*
> > +	 * Step 1: Deselect HDCP Multiplestream Bit.
> > +	 * Step 2: poll for stream encryption status to be disable.
> > +	 */
> 
> The above comment should be inside the callback, doesn't add value here.
stream_encryption call back is common for enable/disable stream encryption.
probbaly it would be better to nuke the above comment in case not adds value here.
Thanks,
Anshuman.
> 
> > +	if (hdcp->shim->stream_encryption) {
> > +		ret = hdcp->shim->stream_encryption(dig_port, false);
> > +		if (ret) {
> > +			drm_err(&dev_priv->drm, "Failed to disable HDCP 1.4
> > stream enc\n");
> > +			return ret;
> > +		}
> > +		drm_dbg_kms(&dev_priv->drm, "HDCP 1.4 trans %s stream
> > encryption disabled\n",
> > +			    transcoder_name(hdcp->stream_transcoder));
> > +	}
> > 
> >  	/*
> > -	 * If there are other connectors on this port using HDCP, don't disable
> > -	 * it. Instead, toggle the HDCP signalling off on that particular
> > -	 * connector/pipe and exit.
> > +	 * If there are other connectors on this port using HDCP, don't disable it.
> > +	 * Repeat steps 1-2 for each stream that no longer requires encryption.
> >  	 */
> > -	if (dig_port->num_hdcp_streams > 0) {
> > -		ret = hdcp->shim->toggle_signalling(dig_port,
> > -						    cpu_transcoder, false);
> > -		if (ret)
> > -			DRM_ERROR("Failed to disable HDCP signalling\n");
> > +	if (dig_port->num_hdcp_streams > 0)
> >  		return ret;
> > -	}
> > 
> >  	hdcp->hdcp_encrypted = false;
> >  	intel_de_write(dev_priv, HDCP_CONF(dev_priv, cpu_transcoder, port), 0);
> > --
> > 2.26.2
>
diff mbox series

Patch

diff --git a/drivers/gpu/drm/i915/display/intel_dp_mst.c b/drivers/gpu/drm/i915/display/intel_dp_mst.c
index 16865b200062..f00e12fc83e8 100644
--- a/drivers/gpu/drm/i915/display/intel_dp_mst.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_mst.c
@@ -826,13 +826,9 @@  static struct drm_connector *intel_dp_add_mst_connector(struct drm_dp_mst_topolo
 	intel_attach_force_audio_property(connector);
 	intel_attach_broadcast_rgb_property(connector);
 
-
-	/* TODO: Figure out how to make HDCP work on GEN12+ */
-	if (INTEL_GEN(dev_priv) < 12) {
-		ret = intel_dp_init_hdcp(dig_port, intel_connector);
-		if (ret)
-			DRM_DEBUG_KMS("HDCP init failed, skipping.\n");
-	}
+	ret = intel_dp_init_hdcp(dig_port, intel_connector);
+	if (ret)
+		drm_dbg_kms(&dev_priv->drm, "HDCP init failed, skipping.\n");
 
 	/*
 	 * Reuse the prop from the SST connector because we're
diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c
index 61252d4be3dd..46c9bd588db1 100644
--- a/drivers/gpu/drm/i915/display/intel_hdcp.c
+++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
@@ -612,7 +612,12 @@  int intel_hdcp_auth_downstream(struct intel_connector *connector)
 	return ret;
 }
 
-/* Implements Part 1 of the HDCP authorization procedure */
+/*
+ * Implements Part 1 of the HDCP authorization procedure.
+ * Authentication Part 1 steps for Multi-stream DisplayPort.
+ * Step 1. Auth Part 1 sequence on the driving MST Trasport Link.
+ * Step 2. Enable encryption for each stream that requires encryption.
+ */
 static int intel_hdcp_auth(struct intel_connector *connector)
 {
 	struct intel_digital_port *dig_port = intel_attached_dig_port(connector);
@@ -766,10 +771,16 @@  static int intel_hdcp_auth(struct intel_connector *connector)
 		return -ETIMEDOUT;
 	}
 
-	/*
-	 * XXX: If we have MST-connected devices, we need to enable encryption
-	 * on those as well.
-	 */
+	/* DP MST Auth Part 1 Step 2.a and Step 2.b */
+	if (shim->stream_encryption) {
+		ret = shim->stream_encryption(dig_port, true);
+		if (ret) {
+			drm_err(&dev_priv->drm, "Failed to enable HDCP 1.4 stream enc\n");
+			return ret;
+		}
+		drm_dbg_kms(&dev_priv->drm, "HDCP 1.4 tras %s stream encrypted\n",
+			    transcoder_name(hdcp->stream_transcoder));
+	}
 
 	if (repeater_present)
 		return intel_hdcp_auth_downstream(connector);
@@ -790,19 +801,26 @@  static int _intel_hdcp_disable(struct intel_connector *connector)
 
 	drm_dbg_kms(&dev_priv->drm, "[%s:%d] HDCP is being disabled...\n",
 		    connector->base.name, connector->base.base.id);
+	/*
+	 * Step 1: Deselect HDCP Multiplestream Bit.
+	 * Step 2: poll for stream encryption status to be disable.
+	 */
+	if (hdcp->shim->stream_encryption) {
+		ret = hdcp->shim->stream_encryption(dig_port, false);
+		if (ret) {
+			drm_err(&dev_priv->drm, "Failed to disable HDCP 1.4 stream enc\n");
+			return ret;
+		}
+		drm_dbg_kms(&dev_priv->drm, "HDCP 1.4 trans %s stream encryption disabled\n",
+			    transcoder_name(hdcp->stream_transcoder));
+	}
 
 	/*
-	 * If there are other connectors on this port using HDCP, don't disable
-	 * it. Instead, toggle the HDCP signalling off on that particular
-	 * connector/pipe and exit.
+	 * If there are other connectors on this port using HDCP, don't disable it.
+	 * Repeat steps 1-2 for each stream that no longer requires encryption.
 	 */
-	if (dig_port->num_hdcp_streams > 0) {
-		ret = hdcp->shim->toggle_signalling(dig_port,
-						    cpu_transcoder, false);
-		if (ret)
-			DRM_ERROR("Failed to disable HDCP signalling\n");
+	if (dig_port->num_hdcp_streams > 0)
 		return ret;
-	}
 
 	hdcp->hdcp_encrypted = false;
 	intel_de_write(dev_priv, HDCP_CONF(dev_priv, cpu_transcoder, port), 0);