Commit 50e945cb authored by Anshuman Gupta's avatar Anshuman Gupta
Browse files

drm/i915/hdcp: mst streams type1 capability check 



It requires to check streams type1 capability in mst topology
by checking Rxinfo instead connector HDCP2.x capability in
order to enforce type0 stream encryption in a mix of
HDCP {1.x,2.x} mst topology.
Rxcaps always shows HDCP 2.x capability of immediate downstream
connector. Let's use Rxinfo HDCP1_DEVICE_DOWNSTREAM bit to
detect a HDCP {1.x,2.x} mix mst topology.

Cc: Sean Paul <seanpaul@chromium.org>
Cc: Ramalingam C <ramalingam.c@intel.com>
Signed-off-by: default avatarAnshuman Gupta <anshuman.gupta@intel.com>
Reviewed-by: default avatarAnkit Nautiyal <ankit.k.nautiyal@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210319091732.17547-1-anshuman.gupta@intel.com
parent 053ffdd1

drivers/gpu/drm/i915/display/intel_display_types.h

+4 −0
Original line number Diff line number Diff line
@@ -387,6 +387,10 @@ struct intel_hdcp_shim { 
	int (*hdcp_2_2_capable)(struct intel_digital_port *dig_port,

				bool *capable);



	/* Detects whether a HDCP 1.4 sink connected in MST topology */

	int (*streams_type1_capable)(struct intel_connector *connector,

				     bool *capable);



	/* Write HDCP2.2 messages */

	int (*write_2_2_msg)(struct intel_digital_port *dig_port,

			     void *buf, size_t size);

drivers/gpu/drm/i915/display/intel_dp_hdcp.c

+39 −0
Original line number Diff line number Diff line
@@ -478,6 +478,23 @@ int intel_dp_hdcp2_write_msg(struct intel_digital_port *dig_port, 
	return size;

}



static int

get_rxinfo_hdcp_1_dev_downstream(struct intel_digital_port *dig_port, bool *hdcp_1_x)

{

	u8 rx_info[HDCP_2_2_RXINFO_LEN];

	int ret;



	ret = drm_dp_dpcd_read(&dig_port->dp.aux,

			       DP_HDCP_2_2_REG_RXINFO_OFFSET,

			       (void *)rx_info, HDCP_2_2_RXINFO_LEN);



	if (ret != HDCP_2_2_RXINFO_LEN)

		return ret >= 0 ? -EIO : ret;



	*hdcp_1_x = HDCP_2_2_HDCP1_DEVICE_CONNECTED(rx_info[1]) ? true : false;

	return 0;

}



static

ssize_t get_receiver_id_list_size(struct intel_digital_port *dig_port)

{
@@ -626,6 +643,27 @@ int intel_dp_hdcp2_capable(struct intel_digital_port *dig_port, 
	return 0;

}



static

int intel_dp_mst_streams_type1_capable(struct intel_connector *connector,

				       bool *capable)

{

	struct intel_digital_port *dig_port = intel_attached_dig_port(connector);

	struct drm_i915_private *i915 = to_i915(dig_port->base.base.dev);

	int ret;

	bool hdcp_1_x;



	ret = get_rxinfo_hdcp_1_dev_downstream(dig_port, &hdcp_1_x);

	if (ret) {

		drm_dbg_kms(&i915->drm,

			    "[%s:%d] failed to read RxInfo ret=%d\n",

			    connector->base.name, connector->base.base.id, ret);

		return ret;

	}



	*capable = !hdcp_1_x;

	return 0;

}



static const struct intel_hdcp_shim intel_dp_hdcp_shim = {

	.write_an_aksv = intel_dp_hdcp_write_an_aksv,

	.read_bksv = intel_dp_hdcp_read_bksv,
@@ -774,6 +812,7 @@ static const struct intel_hdcp_shim intel_dp_mst_hdcp_shim = { 
	.stream_2_2_encryption = intel_dp_mst_hdcp2_stream_encryption,

	.check_2_2_link = intel_dp_mst_hdcp2_check_link,

	.hdcp_2_2_capable = intel_dp_hdcp2_capable,

	.streams_type1_capable = intel_dp_mst_streams_type1_capable,

	.protocol = HDCP_PROTOCOL_DP,

};

drivers/gpu/drm/i915/display/intel_hdcp.c

+16 −1
Original line number Diff line number Diff line
@@ -32,6 +32,21 @@ static int intel_conn_to_vcpi(struct intel_connector *connector) 
	return connector->port	? connector->port->vcpi.vcpi : 0;

}



static bool

intel_streams_type1_capable(struct intel_connector *connector)

{

	const struct intel_hdcp_shim *shim = connector->hdcp.shim;

	bool capable = false;



	if (!shim)

		return capable;



	if (shim->streams_type1_capable)

		shim->streams_type1_capable(connector, &capable);



	return capable;

}



/*

 * intel_hdcp_required_content_stream selects the most highest common possible HDCP

 * content_type for all streams in DP MST topology because security f/w doesn't
@@ -70,7 +85,7 @@ intel_hdcp_required_content_stream(struct intel_digital_port *dig_port) 
		if (conn_dig_port != dig_port)

			continue;



		if (!enforce_type0 && !intel_hdcp2_capable(connector))

		if (!enforce_type0 && !intel_streams_type1_capable(connector))

			enforce_type0 = true;



		data->streams[data->k].stream_id = intel_conn_to_vcpi(connector);