drm/i915: terminate reauth at stream management failure

As per the HDCP2.2 compliance test 1B-10 expectation, when stream
management for a repeater fails, we retry thrice and when it fails
in all retries, HDCP2.2 reauthentication aborted at kernel.

v2:
  seq_num_m++ is extended for steam management failures too.[Anshuman]
v3:
  use drm_dbg_kms instead of DRM_DEBUG_KMS [Anshuman]
v4:
  dev_priv is used as i915 [JaniN]
v5:
  Few improvisements are done [Sean]

Signed-off-by: Ramalingam C <ramalingam.c@intel.com>
Tested-by: Anshuman Gupta <anshuman.gupta@intel.com>
Reviewed-by: Anshuman Gupta <anshuman.gupta@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20200923132435.17039-2-anshuman.gupta@intel.com

diff --git a/drivers/gpu/drm/i915/display/intel_hdcp.c b/drivers/gpu/drm/i915/display/intel_hdcp.c
index 5492076d1ae0983b05376fc6a0f0ce690c0b0efc..d750bb57f25251afd4a02c09c99bfccfc6d50b47 100644 (file)
--- a/drivers/gpu/drm/i915/display/intel_hdcp.c
+++ b/drivers/gpu/drm/i915/display/intel_hdcp.c
@@ -1445,7 +1445,7 @@ 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 *dig_port = intel_attached_dig_port(connector);
        struct drm_i915_private *i915 = to_i915(connector->base.dev);
@@ -1472,28 +1472,25 @@ int hdcp2_propagate_stream_management_info(struct intel_connector *connector)
        ret = shim->write_2_2_msg(dig_port, &msgs.stream_manage,
                                  sizeof(msgs.stream_manage));
        if (ret < 0)
-               return ret;
+               goto out;
 
        ret = shim->read_2_2_msg(dig_port, HDCP_2_2_REP_STREAM_READY,
                                 &msgs.stream_ready, sizeof(msgs.stream_ready));
        if (ret < 0)
-               return ret;
+               goto out;
 
        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;
 
+out:
        hdcp->seq_num_m++;
-
        if (hdcp->seq_num_m > HDCP_2_2_SEQ_NUM_MAX) {
                drm_dbg_kms(&i915->drm, "seq_num_m roll over.\n");
-               return -1;
+               return -ERANGE;
        }
 
-       return 0;
+       return ret;
 }
 
 static
@@ -1564,17 +1561,6 @@ 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 *dig_port = intel_attached_dig_port(connector);
@@ -1611,7 +1597,7 @@ 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_dbg_kms(&i915->drm,
                                    "Repeater Auth Failed. Err: %d\n", ret);
@@ -1619,11 +1605,6 @@ static int hdcp2_authenticate_sink(struct intel_connector *connector)
                }
        }
 
-       hdcp->port_data.streams[0].stream_type = hdcp->content_type;
-       ret = hdcp2_authenticate_port(connector);
-       if (ret < 0)
-               return ret;
-
        return ret;
 }
 
@@ -1704,15 +1685,52 @@ static int hdcp2_disable_encryption(struct intel_connector *connector)
        return ret;
 }
 
+static int
+hdcp2_propagate_stream_management_info(struct intel_connector *connector)
+{
+       struct drm_i915_private *i915 = to_i915(connector->base.dev);
+       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;
+
+               drm_dbg_kms(&i915->drm,
+                           "HDCP2 stream management %d of %d Failed.(%d)\n",
+                           i + 1, tries, ret);
+       }
+
+       return ret;
+}
+
 static int hdcp2_authenticate_and_encrypt(struct intel_connector *connector)
 {
        struct drm_i915_private *i915 = to_i915(connector->base.dev);
+       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);
+                       if (ret) {
+                               drm_dbg_kms(&i915->drm,
+                                           "Stream management failed.(%d)\n",
+                                           ret);
+                               break;
+                       }
+                       hdcp->port_data.streams[0].stream_type =
+                                                       hdcp->content_type;
+                       ret = hdcp2_authenticate_port(connector);
+                       if (!ret)
+                               break;
+                       drm_dbg_kms(&i915->drm, "HDCP2 port auth failed.(%d)\n",
+                                   ret);
+               }
 
                /* Clearing the mei hdcp session */
                drm_dbg_kms(&i915->drm, "HDCP2.2 Auth %d of %d Failed.(%d)\n",
@@ -1721,7 +1739,7 @@ static int hdcp2_authenticate_and_encrypt(struct intel_connector *connector)
                        drm_dbg_kms(&i915->drm, "Port deauth failed.\n");
        }
 
-       if (i != tries) {
+       if (!ret) {
                /*
                 * Ensuring the required 200mSec min time interval between
                 * Session Key Exchange and encryption.