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: Anshuman Gupta <anshuman.gupta@intel.com>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20210319091732.17547-1-anshuman.gupta@intel.com

diff --git a/drivers/gpu/drm/i915/display/intel_display_types.h b/drivers/gpu/drm/i915/display/intel_display_types.h
index 8d1bb9f..946e030 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_display_types.h
+++ b/drivers/gpu/drm/i915/display/intel_display_types.h
@@ -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);

diff --git a/drivers/gpu/drm/i915/display/intel_dp_hdcp.c b/drivers/gpu/drm/i915/display/intel_dp_hdcp.c
index 40c516e..d8b2960 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_dp_hdcp.c
+++ b/drivers/gpu/drm/i915/display/intel_dp_hdcp.c
@@ -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,
 };
 

diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c
index ae1371c..5b2e262 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_hdcp.c
+++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
@@ -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);