Commit d849178e authored by Ramalingam C's avatar Ramalingam C Committed by Daniel Vetter
Browse files

drm/i915: Implement HDCP2.2 repeater authentication 



Implements the HDCP2.2 repeaters authentication steps such as verifying
the downstream topology and sending stream management information.

v2: Rebased.
v3:
  -EINVAL is returned for topology error and rollover scenario.
  Endianness conversion func from drm_hdcp.h is used [Uma]
v4:
  Rebased as part of patches reordering.
  Defined the mei service functions [Daniel]
v5:
  Redefined the mei service functions as per comp redesign.
v6:
  %s/uintxx_t/uxx
  Check for comp_master is removed.
v7:
  Adjust to the new mei interface.
  style issue fixed.
v8:
  drm_hdcp.h change is moved into separate patch [Daniel]
v9:
  %s/__swab16/cpu_to_be16. [Tomas]
  Reviewed-by Uma.

Signed-off-by: default avatarRamalingam C <ramalingam.c@intel.com>
Reviewed-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
Reviewed-by: default avatarUma Shankar <uma.shankar@intel.com>
Signed-off-by: default avatarDaniel Vetter <daniel.vetter@ffwll.ch>
Link: https://patchwork.freedesktop.org/patch/msgid/1550338640-17470-9-git-send-email-ramalingam.c@intel.com
parent bd90d7c7

drivers/gpu/drm/i915/intel_hdcp.c

+123 −2
Original line number Diff line number Diff line
@@ -1041,7 +1041,7 @@ static int hdcp2_prepare_skey(struct intel_connector *connector, 
	return ret;

}



static __attribute__((unused)) int

static int

hdcp2_verify_rep_topology_prepare_ack(struct intel_connector *connector,

				      struct hdcp2_rep_send_receiverid_list

								*rep_topology,
@@ -1070,7 +1070,7 @@ hdcp2_verify_rep_topology_prepare_ack(struct intel_connector *connector, 
	return ret;

}



static __attribute__((unused)) int

static int

hdcp2_verify_mprime(struct intel_connector *connector,

		    struct hdcp2_rep_stream_ready *stream_ready)

{
@@ -1279,6 +1279,119 @@ static int hdcp2_session_key_exchange(struct intel_connector *connector) 
	return 0;

}



static

int hdcp2_propagate_stream_management_info(struct intel_connector *connector)

{

	struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);

	struct intel_hdcp *hdcp = &connector->hdcp;

	union {

		struct hdcp2_rep_stream_manage stream_manage;

		struct hdcp2_rep_stream_ready stream_ready;

	} msgs;

	const struct intel_hdcp_shim *shim = hdcp->shim;

	int ret;



	/* Prepare RepeaterAuth_Stream_Manage msg */

	msgs.stream_manage.msg_id = HDCP_2_2_REP_STREAM_MANAGE;

	drm_hdcp2_u32_to_seq_num(msgs.stream_manage.seq_num_m, hdcp->seq_num_m);



	/* K no of streams is fixed as 1. Stored as big-endian. */

	msgs.stream_manage.k = cpu_to_be16(1);



	/* For HDMI this is forced to be 0x0. For DP SST also this is 0x0. */

	msgs.stream_manage.streams[0].stream_id = 0;

	msgs.stream_manage.streams[0].stream_type = hdcp->content_type;



	/* Send it to Repeater */

	ret = shim->write_2_2_msg(intel_dig_port, &msgs.stream_manage,

				  sizeof(msgs.stream_manage));

	if (ret < 0)

		return ret;



	ret = shim->read_2_2_msg(intel_dig_port, HDCP_2_2_REP_STREAM_READY,

				 &msgs.stream_ready, sizeof(msgs.stream_ready));

	if (ret < 0)

		return ret;



	hdcp->port_data.seq_num_m = hdcp->seq_num_m;

	hdcp->port_data.streams[0].stream_type = hdcp->content_type;



	ret = hdcp2_verify_mprime(connector, &msgs.stream_ready);

	if (ret < 0)

		return ret;



	hdcp->seq_num_m++;



	if (hdcp->seq_num_m > HDCP_2_2_SEQ_NUM_MAX) {

		DRM_DEBUG_KMS("seq_num_m roll over.\n");

		return -1;

	}



	return 0;

}



static

int hdcp2_authenticate_repeater_topology(struct intel_connector *connector)

{

	struct intel_digital_port *intel_dig_port = conn_to_dig_port(connector);

	struct intel_hdcp *hdcp = &connector->hdcp;

	union {

		struct hdcp2_rep_send_receiverid_list recvid_list;

		struct hdcp2_rep_send_ack rep_ack;

	} msgs;

	const struct intel_hdcp_shim *shim = hdcp->shim;

	u8 *rx_info;

	u32 seq_num_v;

	int ret;



	ret = shim->read_2_2_msg(intel_dig_port, HDCP_2_2_REP_SEND_RECVID_LIST,

				 &msgs.recvid_list, sizeof(msgs.recvid_list));

	if (ret < 0)

		return ret;



	rx_info = msgs.recvid_list.rx_info;



	if (HDCP_2_2_MAX_CASCADE_EXCEEDED(rx_info[1]) ||

	    HDCP_2_2_MAX_DEVS_EXCEEDED(rx_info[1])) {

		DRM_DEBUG_KMS("Topology Max Size Exceeded\n");

		return -EINVAL;

	}



	/* Converting and Storing the seq_num_v to local variable as DWORD */

	seq_num_v = drm_hdcp2_seq_num_to_u32(msgs.recvid_list.seq_num_v);



	if (seq_num_v < hdcp->seq_num_v) {

		/* Roll over of the seq_num_v from repeater. Reauthenticate. */

		DRM_DEBUG_KMS("Seq_num_v roll over.\n");

		return -EINVAL;

	}



	ret = hdcp2_verify_rep_topology_prepare_ack(connector,

						    &msgs.recvid_list,

						    &msgs.rep_ack);

	if (ret < 0)

		return ret;



	hdcp->seq_num_v = seq_num_v;

	ret = shim->write_2_2_msg(intel_dig_port, &msgs.rep_ack,

				  sizeof(msgs.rep_ack));

	if (ret < 0)

		return ret;



	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 = conn_to_dig_port(connector);
@@ -1312,6 +1425,14 @@ static int hdcp2_authenticate_sink(struct intel_connector *connector) 
			return ret;

	}



	if (hdcp->is_repeater) {

		ret = hdcp2_authenticate_repeater(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)